Noninvasive determination of respiratory ozone absorption: development of a fast-responding ozone analyzer.

PubMed

Ultman, J S; Ben-Jebria, A

1991-03-01

We developed a chemiluminescent ozone analyzer and constructed an ozone bolus generator with the eventual goal of using a bolus-response method to measure noninvasively the longitudinal distribution of ozone absorption in human lungs. Because the analyzer will be used to sample gases within a single breath, it must have a sufficiently rapid response to monitor changes in ozone concentration during a four-second breathing period, yet its sampling flow must be small enough that it does not interfere with quiet respiratory flows of 300 mL/sec. Our analyzer, which is based on the chemiluminescent reaction between 2-methyl-2-butene and ozone, has favorable performance characteristics: a 90 percent step-response time of 110 msec; a linear calibration from 0.03 to 10 parts per million (ppm)2 with a sensitivity of 2.3 nA/ppm; a signal-to-noise ratio of 30 evaluated at 0.5 ppm; and a minimum detection limit of 0.017 ppm. At an airflow corresponding to quiet breathing, the ozone generator is capable of producing single boluses with a peak ozone fraction as high as 4 ppm, but containing only 0.35 micrograms of ozone dispersed over a small volume of 19 mL. To test the combination of ozone analyzer and bolus generator, we performed bolus-response experiments at steady airflows of 50 to 200 mL/sec in excised pig and sheep tracheas. In spite of the small surface area available for radial diffusion, we found that 25 to 50 percent of the ozone introduced into the trachea was absorbed. By comparing the mathematical moments of the bolus input and the response curves to the predictions of a diffusion theory, we computed an absorption coefficient (K). The values of K increased with increasing airflow, implying that ozone absorption is limited by diffusion processes in the airway lumen as well as in the surrounding tissue.

Effect of an ozone injury-retardant chemical on isozyme profiles from alfalfa callus in vitro

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rier, J.P.; Sood, V.K.; Whitaker, A.

1983-01-01

Plant ozone injury retardant (EDU or ethylenediurea) at 1.0 ppm inhibited growth of callus of alfalfa cultivars Williamsburg (ozone-sensitive) and MSB-CW5An2(ozone-insensitive) germplasm of Medicago sative. The presence of EDU(0.1 ppm) in growth medium increased the number of protein and peroxidase isozyme bands in alfalfa cultivar stem callus and ozone modified their intensities. Protein profiles of MSB stem callus from media containing EDU or exposed to ozone were unchanged. Marked differences were observed between the peroxidase profiles of ozonated and control ozone-insensitive stem callus from media containing EDU. Protein profiles of ozonated ozone-insensitive leaf callus differed slightly from controls.

Ozone treatment of shell eggs to preserve functional quality and enhance shelf life during storage.

PubMed

Yüceer, Muhammed; Aday, Mehmet Seçkin; Caner, Cengiz

2016-06-01

Eggs have long been recognised as a source of high-quality proteins. Many methods exist to extend shelf life of food and one of them is ozone treatment, which is an emerging technology for disinfecting surfaces in the food industry. This study aimed to extend the shelf life of fresh eggs using gaseous ozone treatments at concentrations of 2, 4 and 6 ppm with exposure times of 2 and 5 min during storage for 6 weeks at 24 °C. The effect of the treatments on interior quality and functional properties of eggs is also reported. Ozone concentration and exposure time significantly affected the Haugh unit (HU), yolk index, albumen pH, relative whipping capacity (RWC), and albumen viscosity of eggs during the storage. Control eggs had the highest albumen pH and lowest albumen viscosity. Attributes such as albumen pH and RWC of eggs exposed to ozone treatments were better than the control samples. The measurement results showed that ozone concentration at 6 ppm and exposure time of 5 min can be applied to fresh eggs and extend shelf life up to 6 weeks at 24 °C storage period. Ozone treatments helped to maintain egg quality for a longer time. Ozone concentrations at 2 and 4 ppm showed promising results in maintaining internal quality and functional properties of fresh eggs during storage. Ozone at high concentration (6 ppm) caused a detrimental effect on eggshell quality. As a result, this study demonstrated that ozone treatments of 2, and especially 4 and 6 ppm concentration maintained eggshell quality during the storage. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Pulmonary responses of healthy young adults exposed to 0.06 and 0.08 ppm ozone

EPA Science Inventory

Background. Previous studies have shown small but significant decreases in spirometric lung function in healthy young adults exposed to 0.08 ppm ozone. It is unclear, however, if such effects may are seen at concentrations below 0.08 ppm. Methods. A group of 30 healthy young adul...

The effect of ozonated cooling water on the corrosion behavior of stainless steel, titanium and copper alloys. Ozone biocidal action on sessile and planktonic bacteria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Videla, H.A.; Guiamet, P.S.; Mele, M.F.L. de

1999-11-01

Two aspects of ozone utilization as sole chemical treatment for cooling water demand a better understanding: (a) the effect of dissolved ozone on the corrosion behavior of heat exchanger structural materials and (b) the biocidal action of ozone on bacterial biofilms. To assess the effect of ozone dissolved in synthetic cooling water on the corrosion behavior of different structural materials (stainless steel; 70:30 copper-nickel; aluminum brass and titanium), voltamperometric experiments and corrosion potential vs. time measurements were made at ozone concentrations between 0.1 and 1.2 ppm. Present results show that the passive behavior of stainless steel and titanium is notmore » affected by dissolved ozone whereas copper alloys are susceptible to corrosion in the presence of ozone. To study the biocidal action of various concentrations of dissolved ozone against planktonic and sessile bacteria, liquid cultures and biofilms of Pseudomonas fluorescense, formed on different structural materials, were used at different contact times. The results show that dissolved ozone is an effective biocide for controlling planktonic cells but its effectiveness decreases in the presence of sessile bacteria and the extracellular polymeric matrix of the biofilm. It is suggested that the penetration of ozone through the biofilm depends on the simultaneous diffusion and reaction of the biocide with the biofilm matrix which may exhibit local differences in biomass distribution and hydrodynamic conditions.« less

Lung Function and Inflammatory responses in healthy young adults exposed to 0.06 ppm Ozone for 6.6 hours

EPA Science Inventory

Rationale: Exposure to ozone causes a decrease in spirometric lung function and an increase in airway inflammation in healthy young adults at concentrations as low as 0.08 ppm close to the the National Ambient Air Quality Standard for ground level ozone. Objectives: To test wheth...

Simultaneous removal of 2,4,6-tribromophenol from water and bromate ion minimization by ozonation.

PubMed

Gounden, Asogan N; Singh, Sooboo; Jonnalagadda, Sreekantha B

2018-06-02

The study investigates the degradation of 2,4,6-tribromophenol (2,4,6-TBP) and the influence of solution pH, alkalinity, H 2 O 2 and O 3 dosage. Debromination efficiency of 2,4,6-TBP was the highest in basic water (pH = 10.61). The extent of TOC removal compared favourably with the amount of substrate converted, suggesting favourable mineralization of oxygenated by-products (OBPs). Ozonation in basic water favoured the formation of toxicBrO 3 - , while in acidic water (pH = 2.27) BrO 3 - yield was lowest. In acidic water the presence of CO 3 2- showed negligible effect on conversion, TOC and  BrO 3 - yield compared to ozonation alone. In basic water both 2,4,6-TBP conversion and TOC removal decreased with an increase in CO 3 2- , hence minimizing BrO 3 - formation. The O 3 /H 2 O 2 process showed an improvement in the debromination efficiency and TOC data revealed that total mineralization of OBP's was achieved. However, only 10% H 2 O 2 was able to effectively decrease BrO 3 - formation. Increasing the ozone concentration from 20 to 100 ppm enhanced the conversion of 2,4,6-TBP and TOC removal. At low ozone concentrations poor mineralization of OBP's occurred, while complete mineralization was achieved at higher ozone dose. The reaction pathways for ozone degradation of 2,4,6-TBP in acidic and basic waters is proposed. Copyright © 2018 Elsevier B.V. All rights reserved.

Using an extractive Fourier transform infrared spectrometer for improving cleanroom air quality in a semiconductor manufacturing plant.

PubMed

Li, Shou-Nan; Chang, Chin-Ta; Shih, Hui-Ya; Tang, Andy; Li, Alen; Chen, Yin-Yung

2003-01-01

A mobile extractive Fourier transform infrared (FTIR) spectrometer was successfully used to locate, identify, and quantify the "odor" sources inside the cleanroom of a semiconductor manufacturing plant. It was found that ozone (O(3)) gas with a peak concentration of 120 ppm was unexpectedly releasing from a headspace of a drain for transporting used ozonized water and that silicon tetrafluoride (SiF(4)) with a peak concentration of 3 ppm was off-gassed from silicon wafers after dry-etching processing. When the sources of the odors was pinpointed by the FTIR, engineering control measures were applied. For O(3) control, a water-sealed pipeline was added to prevent the O(3) gas (emitting from the ozonized water) from entering the mixing unit. A ventilation system also was applied to the mixing unit in case of O(3) release. For SiF(4) mitigation, before the wafer-out chamber was opened, N(2) gas with a flow rate of 150 L/min was used for 100 sec to purge the wafer-out chamber, and a vacuum system was simultaneously activated to pump away the purging N(2). The effectiveness of the control measures was assured by using the FTIR. In addition, the FTIR was used to monitor the potential hazardous gas emissions during preventative maintenance of the semiconductor manufacturing equipment.

A comparison of height growth and leaf parameters of hybrid poplar cuttings grown in ozone-fumigated atmospheres

Treesearch

Keith F. Jensen

1979-01-01

Hybrid poplar cuttings were fumigated with an ozone dosage of 15 ppm-hours. One treatment was a steady fumigation at 0.2 ppm while the second fumigation fluctuated between 0.1 and 0.3 ppm. No significant differences were found in cutting height, leaf area, leaf width, and leaf dry weight, but significant differences were found in chlorophyll content and carbohydrate...

Removing volatile organic compounds in cooking fume by nano-sized TiO2 photocatalytic reaction combined with ozone oxidation technique.

PubMed

Li, Yu-Hua; Cheng, Su-Wen; Yuan, Chung-Shin; Lai, Tzu-Fan; Hung, Chung-Hsuang

2018-06-05

Chinese cooking fume is one of the sources of volatile organic compounds (VOCs) in the air. An innovative control technology combining photocatalytic degradation and ozone oxidation (UV/TiO 2 +O 3 ) was developed to decompose VOCs in the cooking fume. Fiberglass filter (FGF) coated with TiO 2 was prepared by an impregnation procedure. A continuous-flow reaction system was self-designed by combining photocatalysis with advanced ozone oxidation technique. By passing the simulated cooking fume through the FGF, the VOC decomposition efficiency in the cooking fume could be increased by about 10%. The decomposition efficiency of VOCs in the cooking fume increased and then decreased with the inlet VOC concentration. A maximum VOC decomposition efficiency of 64% was obtained at 100 ppm. Similar trend was observed for reaction temperature with the VOC decomposition efficiencies ranging from 64 to 68%. Moreover, inlet ozone concentration had a positive effect on the decomposition of VOCs in the cooking fume for inlet ozone≤1000 ppm and leveled off for inlet ozone>1000 ppm. 34% of VOC decomposition efficiency was achieved solely by ozone oxidation with or without near-UV irradiation. A maximum of 75% and 94% VOC decomposition efficiency could be achieved by O 3 +UV/TiO 2 and UV/TiO 2 +O 3 techniques, respectively. The maximum decomposition efficiencies of VOCs decreased to 79% for using UV/TiO 2 +O 3 technique with adding water in the oil fume. Comparing the chromatographical species of VOCs in the oil fume before and after the decomposition of VOCs by using UV/TiO 2 +O 3 technique, we found that both TVOC and VOC species in the oil fume were effectively decomposed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Health-hazard evaluation report HETA 91-158-2161, Immaculate Heart of Mary Church, Cincinnati, Ohio

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cook, C.K.

1991-11-01

In response to a request from a representative of the Immaculate Heart of Mary Church (SIC-8661), an investigation was made of indoor air quality in the church office. Particular attention was directed toward laser printer and photocopier emissions. Employees had complained of headaches, dizziness, confusion, nausea, eye irritation, and dry nose and throat. Day shift employees performed general office duties, often using a photocopier and a laser printer. Real time ozone (10028156) concentrations ranged from below the limit of detection (LOD) to 0.05 parts per million (ppm) in the breathing zone, all below the NIOSH limit for short term exposuremore » of 0.10ppm. Ozone concentrations as high as 0.56ppm were detected at the laser printer exhaust. Carbon-dioxide (124389) concentrations ranged from 400 to 850ppm. Respirable dust concentrations ranged from below the LOD to 90 micrograms per cubic meter. Carbon-monoxide (630080) levels were not above the LOD of 5ppm. No volatile organic carbons were detected. Temperature and relative humidity levels were within the guidelines. Some of the symptoms were consistent with ozone exposure. The author concludes that efforts should be made to reduce ozone exposures. The author recommends relocating the laser printer, providing additional outside air to the building, and checking for possible overloading or inefficiency in the ozone filter in the printer.« less

Photolysis of RDX in Aqueous Solution, With and Without Ozone

DTIC Science & Technology

1979-02-09

and compared with a standard prepared from the same TNT solution and an accurately weighed RDX sample in acetone ( 40 ppm). The GC analysis of the...aqueous carbon-14 RDX agreed with the weight ( 40 ppm). A stock solution of carbon-12 RDX in tap water was prepared by stirring an excess of RDX in 2 liters...as volatiles 8.4% " i10 7, 77 Y 40 ’ NSWC/WOL TR 78-175 Chemical Analysis of Acidified Reaction Mixture Nitrate ion: 4.91 x 10- M Ammonia: 2.5 x 10 -4

Effect of an ozone injury retardant chemical on isozyme profiles from alfalfa callus in vitro

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rier, J.P. Jr.; Sood, V.K.; Whitaker, A.

1983-01-01

Plant ozone injury retardant N-(2-(2-oxo-1-imidazolidinyl)-ethyl)-N'-phenylurea (EDU or ethylenediurea) at 1.0 ppm inhibited growth of callus of alfalfa cultivars Williamsburg (ozone-sensitive) and MSB-CW5An2 (ozone-insensitive) germplasm of Medicago sativa. The presence of EDU (0.1 ppm)in the growth medium increased the number of protein and peroxidase isozyme bands in alfalfa cultivar Williamsburg stem callus and ozone modified their intensities. Protein profiles of MSB stem callus from media containing EDU or exposed to ozone were unchanged. Marked differences were observed between the peroxidase profiles of ozonated and control ozone-insensitive stem callus from media containing EDU. Protein profiles of ozonated ozone-sensitive leaf callus differed slightlymore » from controls. The peroxidase profile of ozonated ozone-sensitive leaf callus was not altered when its growth medium contained EDU, but when it was absent, changes were observed in these profiles.« less

Effect of pulsed corona discharge voltage and feed gas flow rate on dissolved ozone concentration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prasetyaningrum, A., E-mail: ajiprasetyaningrum@gmail.com; Ratnawati,; Jos, B.

Ozonization is one of the methods extensively used for water purification and degradation of organic materials. Ozone (O{sub 3}) is recognized as a powerful oxidizing agent. Due to its strong oxidability and better environmental friendless, ozone increasing being used in domestic and industrial applications. Current technology in ozone production utilizes several techniques (corona discharge, ultra violet radiation and electrolysis). This experiment aimed to evaluating effect of voltage and gas flow rate on ozone production with corona discharge. The system consists of two net-type stainless steel electrode placed in a dielectric barrier. Three pulsed voltage (20, 30, 40 KV) and flowmore » rate (5, 10, 15 L/min) were prepare for operation variable at high frequency (3.7 kHz) with AC pulsed power supply. The dissolved ozone concentration depends on the applied high-voltage level, gas flow rate and the discharge exposure duration. The ozone concentration increases with decreasing gas flow rate. Dissolved ozone concentrations greater than 200 ppm can be obtained with a minimum voltage 40 kV.« less

Effect of pulsed corona discharge voltage and feed gas flow rate on dissolved ozone concentration

NASA Astrophysics Data System (ADS)

Prasetyaningrum, A.; Ratnawati, Jos, B.

2015-12-01

Ozonization is one of the methods extensively used for water purification and degradation of organic materials. Ozone (O3) is recognized as a powerful oxidizing agent. Due to its strong oxidability and better environmental friendless, ozone increasing being used in domestic and industrial applications. Current technology in ozone production utilizes several techniques (corona discharge, ultra violet radiation and electrolysis). This experiment aimed to evaluating effect of voltage and gas flow rate on ozone production with corona discharge. The system consists of two net-type stainless steel electrode placed in a dielectric barrier. Three pulsed voltage (20, 30, 40 KV) and flow rate (5, 10, 15 L/min) were prepare for operation variable at high frequency (3.7 kHz) with AC pulsed power supply. The dissolved ozone concentration depends on the applied high-voltage level, gas flow rate and the discharge exposure duration. The ozone concentration increases with decreasing gas flow rate. Dissolved ozone concentrations greater than 200 ppm can be obtained with a minimum voltage 40 kV.

Fumigation characteristics of ozone in postharvest treatment of Kabkab dates (Phoenix dactylifera L.) against selected insect infestation.

PubMed

Niakousari, Mehrdad; Erjaee, Zahra; Javadian, Shahram

2010-04-01

Methyl bromide fumigation, the most accepted quarantine treatment for dates and many other dried commodities, will be phased out by 2015 worldwide. As a result, there is a critical need to develop durable alternatives for methyl bromide as postharvest treatments of agricultural commodities. This article presents a new method for postharvest treatment of Kabkab dates (Phoenix dactylifera L.) by application of gaseous ozone to reduce or eliminate all life stages (adults, larvae, and eggs) of Indian meal moth (Plodia interpunctella) and sawtooth grain beetle (Oryzaephilus surinamensis). The effect of the ozonation process on the sugar content of dates was also evaluated. Infested dates were exposed to ozone concentrations of 600, 1,200, 2,000, and 4,000 ppm for 1 and 2 h. As insect eggs are known to be most tolerant to many chemical or physical treatments, they were additionally exposed to an atmosphere of pure carbon dioxide prior to ozonation. Exposing samples to ozone concentrations of >2,000 ppm for 2 h resulted in complete mortality of larvae and adults. Exposure to 4,000 ppm of ozone for 2 h resulted in 80% mortality of eggs, and exposure to CO(2) prior to ozonation did not improve the effect of ozonation on eggs. Ozone did not have any influence on the sugar content of Kabkab dates.

Responses of subjects with chronic obstructive pulmonary disease after exposures to 0. 3 ppm ozone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kehrl, H.R.; Hazucha, M.J.; Solic, J.J.

1985-05-01

The authors previously reported that the respiratory mechanics of intermittently exercising persons with chronic obstructive pulmonary disease (COPD) were unaffected by a 2-h exposure to 0.2 ppm ozone. Employing a single-blind, cross-over design protocol, 13 white men with nonreversible COPD (9 current smokers; mean FEV1/FVC, 56%) were randomly exposed on 2 consecutive days for 2 h to air and 0.3 ppm ozone. During exposures, subjects exercised (minute ventilation, 26.4 +/- 3.0 L/min) for 7.5 min every 30 min; ventilation and gas exchange measured during exercise showed no difference between exposure days. Pulmonary function tests (spirometry, body plethysmography) obtained before andmore » after exposures were unchanged on the air day. On the ozone day the mean airway resistance and specific airway resistance showed the largest (25 and 22%) changes (p = 0.086 and 0.058, respectively). Arterial oxygen saturation (SaO/sub 2/) obtained in 8 subjects during the last exercise interval showed a mean decrement of 0.95% on the ozone exposure day; this change did not attain significance (p = 0.074). Nevertheless, arterial oxygen desaturation may be a true consequence of low-level ozone exposure in this compromised patient group. As normal subjects undergoing exposures to ozone with slightly higher exercise intensities show a threshold for changes in their respiratory mechanics at approximately 0.3 ppm, these data indicate that persons with COPD are not unduly sensitive to the effects of low-level ozone exposure.« less

Consideration of air quality standards for vegetation with respect to ozone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heggestad, H.E.

1969-06-01

Present evidence suggests that ozone is the most damaging of all air pollutants affecting vegetation. It is the principal oxidant in the photochemical smog complex. Concentrations of ozone have exceeded 0.5 part per million (ppm) in the Los Angeles area. One-tenth of this level for 8 hours is known to injure very sensitive tobacco varieties. Many plant species are visibly affected after a few hours exposure at concentrations much lower than 0.5 ppm. There is also some evidence that ozone reduces plant growth. Many factors must be taken into account when considering standards to protect vegetation from ozone damage. Thesemore » include ozone concentration and methods of measurement, time of exposure, possible additive effects of other pollutants, sensitivity of plant species, their economic value, and the extent of injury which can be tolerated. The response of a species to the pollutant is conditioned by genetic factors and environmental conditions. Lack of specific routine methods for measuring ozone in ambient air is a handicap. California and Colorado established standards for oxidants at 0.15 and 0.10 ppm, respectively, for 1 hour. How these standards relate to the ozone dosage causing acute and chronic injury to various plant species is discussed.« less

Uterine Artery Flow and Offspring Growth in Long-Evans Rats following Maternal Exposure to Ozone during Implantation

PubMed Central

Dye, Janice A.; Ledbetter, Allen D.; Schladweiler, Mette C.; Richards, Judy H.; Snow, Samantha J.; Wood, Charles E.; Henriquez, Andres R.; Thompson, Leslie C.; Farraj, Aimen K.; Hazari, Mehdi S.; Kodavanti, Urmila P.

2017-01-01

Background: Epidemiological studies suggest that increased ozone exposure during gestation may compromise fetal growth. In particular, the implantation stage of pregnancy is considered a key window of susceptibility for this outcome. Objectives: The main goals of this study were to investigate the effects of short-term ozone inhalation during implantation on fetal growth outcomes and to explore the potential for alterations in uterine arterial flow as a contributing mechanism. Methods: Pregnant Long-Evans rats were exposed to filtered air, 0.4 ppm ozone, or 0.8 ppm ozone for 4 h/d during implantation, on gestation days (GD) 5 and 6. Tail cuff blood pressure and uterine artery Doppler ultrasound were measured on GD 15, 19, and 21. To assess whether peri-implantation ozone exposure resulted in sustained pulmonary or systemic health effects, bronchoalveolar lavage fluid, serum metabolic and inflammatory end points, and kidney histopathology were evaluated in dams at GD 21. Growth parameters assessed in GD 21 offspring included fetal weight, length, and body composition. Results: Measures of maternal uterine arterial flow, including resistance index and mean velocity, indicated that resistance increased between GD 15 and GD 21 in 0.8 ppm dams but decreased in controls, although absolute values were similar in both groups on GD 21. Ozone-exposed dams also had lower serum glucose and higher free fatty acid concentrations than controls on GD 21. On GD 21, both male and female offspring had lower body weight than controls, and pooled subsets of 3 male and 3 female fetuses from litters exposed to 0.8 ppm ozone had lower lean mass and fat mass than pooled control offspring. Conclusions: Findings from our experimental model suggest that the offspring of dams exposed to ozone during implantation had reduced growth compared with controls, possibly as a consequence of ozone-induced vascular dysfunction. https://doi.org/10.1289/EHP2019 PMID:29269335

Balloon-borne observations of the development and vertical structure of the Antarctic ozone hole in 1986

NASA Technical Reports Server (NTRS)

Hofmann, D. J.; Harder, J. W.; Rolf, S. R.; Rosen, J. M.

1987-01-01

The vertical distribution of ozone measured at McMurdo Station, Antarctica using balloon-borne sensors on 33 occasions during November 6, 1986 - August 25, 1986 is described. These observations suggest a highly structured cavity confined to the 12-20 km altitude region. In the 17-19 km altitude range, the ozone volume mixing ratio declined from about 2 ppm at the end of August to about 0.5 ppm by mid-October. The average decay in this region can be described as exponential with a half life of about 25 days. While total ozone, as obtained from profile integration, declined only about 35 percent, the integrated ozone between 14 and 18 km declined more than 70 percent. Vertical ozone profiles in the vortex revealed unusual structure with major features from 1 to 5 km thick which had suffered ozone depletions as great as 90 percent.

Effect of an ozone-generating air-purifying device on reducing concentrations of formaldehyde in air

DOE Office of Scientific and Technical Information (OSTI.GOV)

Esswein, E.J.; Boeniger, M.F.

1994-02-01

Formaldehyde, an air contaminant found in many indoor air investigations, poses distinct occupational exposure hazards in certain job categories (e.g., mortuary science) but is also of concern when found or suspected in office buildings and homes. A variety of air-purifying devices (APDs) are currently available or marketed for application to reduce or remove concentrations of a variety of indoor air pollutants through the use of ozone as a chemical oxidant. An investigation was conducted to determine if concentrations of formaldehyde similar to those found in industrial hygiene evaluations of funeral homes could be reduced with the use of an ozone-generatingmore » APD. An ozone-generating APD was placed in an exposure chamber and formaldehyde-containing embalming solution was allowed to evaporate naturally, creating peak and mean chamber concentrations of 2.5 and 1.3 ppm, respectively. Continuous-reading instruments were used to sample for formaldehyde and ozone. Active sampling methods were also used to sample simultaneously for formaldehyde and a possible reactant product, formic acid. Triplicate measurements were made in each of three evaluations: formaldehyde alone, ozone alone, and formaldehyde and ozone combined. Concentrations of formaldehyde were virtually identical with and without 0.5 ppm ozone. No reduction in formaldehyde concentration was found during a 90-minute evaluation using ozone at this concentration with peak and average concentrations of approximately 2.5 and 1.3 ppm formaldehyde, respectively. The results of this investigation suggest that the use of ozone is ineffective in reducing concentrations of formaldehyde. Because ozone has demonstrated health hazards, and is a regulated air contaminant in both the occupational and ambient environment, the use of ozone as an air purification agent in indoor air does not seem warranted. 25 refs., 5 figs., 4 tabs.« less

Precooling and ozone treatments affects postharvest quality of black mulberry (Morus nigra) fruits.

PubMed

Han, Qiang; Gao, Haiyan; Chen, Hangjun; Fang, Xiangjun; Wu, Weijie

2017-04-15

Mulberry (Morus spp.) fruits are delicious and nutritious, but they are highly perishable and have a very short shelf-life for sale in the market. This study investigated the effect and mechanisms of 2ppm ozone and precooling treatments on the postharvest quality of mulberry fruit during refrigerated storage. The results revealed that mulberry fruit subjected to ozone and precooling treatment had higher levels of titratable acidity and total soluble solids content, better retention in firmness and color, and lower decay rate, respiratory intensity, and polyphenol oxidase activity compared to the control. From the analysis of cell ultrastructure and cell wall components of fruit, ozone and precooling treatments also induced shrinkage of the stomata in the epidermis, inhibited bacteria invasion, reduced water transpiration, and delayed the decomposition of the cell walls and the degradation of epidermal tissues. Copyright © 2016. Published by Elsevier Ltd.

Effects of tropospheric ozone on loblolly pine seedlings inoculated with root infecting ophiostomatoid fungi.

PubMed

Chieppa, Jeff; Chappelka, Art; Eckhardt, Lori

2015-12-01

Seedlings from four loblolly pine (Pinus taeda L.) families were exposed in open-top chambers to charcoal-filtered air (CF), non-filtered air (NF) or air amended with ozone to 2 times ambient (2×). Two of the families used were selected for their tolerance to fungi associated with Southern Pine Decline while two were selected for their susceptibility. Seedlings were treated with five inoculation treatments: no wound (NW), wound only (W), wound + media (WM), Grosmannia huntii (GH) and Leptographium terebrantis (LT). After 118 days of exposure (AOT40 = 31 ppm-hr(-1) for 2× ozone) seedling volume, dry matter, chlorophyll content, water potential and lesions were measured and analyzed using ANOVA procedures. Our results indicate that seedlings selected for their susceptibility to root infecting ophiostomatoid fungi were also more sensitive to ozone. Overall lesion length was greater on seedlings exposed to elevated ozone concentrations but was not specific to either root infecting ophiostomatoid fungi. Copyright © 2015 Elsevier Ltd. All rights reserved.

Confirmation of the sterilization effect using a high concentration of ozone gas for the bio-clean room.

PubMed

Iwamura, Takuji; Nagano, Katsunori; Nogami, Toshihiro; Matsuki, Noritomo; Kosaka, Noriyoshi; Shintani, Hideharu; Katoh, Miyoshi

2013-01-01

A high-level aseptic environment must be maintained in bio-cleanrooms used for the manufacture of sterile products. In the past, formaldehyde gas was most commonly used to sterilize bio-cleanrooms, but due to strict residual limitations there has been a need to develop a less toxic alternative choice. The authors have developed a revolutionary new sterilization system using a high concentration of ozone gas and used this system to sterilize an actual bio-cleanroom. This system integrates the ozone gas generator with the air conditioning system by proper control. The design specifications for the system included an ozone gas concentration of 200 ppm or more, relative humidity of 80% or more, and a sterilizing time of 120 min. Blow vents and suction ports were placed to ensure a uniform airflow which would extend through the entire room during ozone gas sterilization. Tests regarding long-term material exposure to ozone gas were conducted when the system was introduced to distinguish usable and unusable materials. In an actually constructed cleanroom, simulations were used to predict the evenness of the diffusion of ozone gas concentration and relative humidity during ozone gas sterilization, and measurements of the actual indoor ozone gas concentration, temperature and relative humidity during sterilization revealed that the ozone concentration and relative humidity needed for sterilization had been achieved generally throughout the entire environment. In addition, the CT value (mg/m(3) (=ppm) × min) , derived by multiplying the ozone gas concentration during ozone gas sterilization by the sterilization time, was equal to or greater than the target value of 24 × 10(3) (ppm·min) . When the results of sterilization in a cleanroom were confirmed using a biological indicator (BI) , negative results were obtained at all measurement points, demonstrating that sterilization was being performed effectively in the actual factory at which the ozone gas sterilization system had been introduced.

Response of the rat erythrocyte to ozone exposure

NASA Technical Reports Server (NTRS)

Larkin, E. C.; Kimzey, S. L.; Siler, K.

1978-01-01

Sprague-Dawley rats were exposed to high (6-8 ppm) and moderate (1.5 ppm) amounts of ozone (O3) for various time periods. Response of the rat erythrocyte to ozone was monitored with red blood cell potassium (rubidium) influx studies, with storage stress combined with ultrastructural studies and with levels of erythrocyte glutathione peroxidase and superoxide dismutase. Erythrocytes of rats exposed to O3 showed no significant changes either in their potassium influx or in their glutathione peroxidase and superoxide dismutase activities compared to controls. Erythrocyte differential counts on O3-exposed animals showed significant changes initially as well as following storage stress compared to controls. Rats exposed to 8 ppm O3 for 4 h showed a marked increase in echinocytes. These consistent transformations from discocytes to echinocytes following O3 exposure suggest latent erythrocyte damage has occurred.

76 FR 3840 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard for the Delaware...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-21

... 4th highest daily 8-hour monitored ozone value during the 2009 ozone season is 0.084 parts per million... Philadelphia Area's 4th highest daily 8-hour monitored value during the 2009 ozone season is 0.084 ppm or less...

Combination of ozonation and photocatalysis for pharmaceutical wastewater treatment

NASA Astrophysics Data System (ADS)

Ratnawati, Enjarlis, Slamet

2017-11-01

The chemical oxygen demand (COD) and phenol removal from pharmaceutical wastewater were investigated using configuration of two circulation batch reactors in a series with ozonation and photocatalytic processes. The ozonation is conducted with O3/granulated activated carbon (O3/GAC), whereas photocatalysis with TiO2 that immobilized on pumice stone (PS-TiO2). The effect of circulation flow rate (10; 12; 15 L/min) and the amount PS-TiO2 (200 g, 250 g, 300 g) were examined. Wastewater of 20 L was circulated pass through the pipe that injected with O3 by the ozone generator, and subsequently flow through two GAC columns, and finally, go through photoreactor that contains photocatalyst PS-TiO2 which equipped with mercury lamp as a photon source. At a time interval, COD and phenol concentration were measured to assess the performance of the process. FESEM imaging confirmed that TiO2 was successfully impregnated on PS, as corroborated by EDX spectra. Meanwhile, degradation process indicated that the combined ozonation and photocatalytic processes (O3/GAC-TiO2) is more efficient compared to the ozonation and photocatalysis alone. For combination process with the circulation flow rate of 10 L/min and 300 g of PS-TiO2,the influent COD of around 1000 ppm are effectively degraded to a final effluent COD of 290 ppm (71% removal) and initial phenol concentration of 4.75 ppm down to 0 ppm for 4 h which this condition fulfill the discharge standards quality. Therefore, this portable prototype reactor is effective that can be used in the pharmaceutical wastewater treatment. For the future, this process condition will be developed for orientation on the industrial applications (portable equipment) since pharmaceutical industries produce wastewater relatively in the small amount.

Products and mechanisms of the reaction of gas phase ozone with organic colorants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grosjean, D.; Druzik, J.R.; Sensharma, D.K.

1988-09-01

Studies carried out in this laboratory have shown that many artists organic colorants fade substantially when exposed to ozone in the dark. These studies typically involved pigment exposure for 12 weeks to purified air containing 0.3-0.4 ppm of ozone at ambient temperature and humidity. These laboratory conditions are equivalent to about six years of exposure inside a typical air-conditioned building in Los Angeles, and the observed fading is therefore directly relevant to possible damage to works of arts in museum settings. Organic colorants that were most ozone-fugitive included natural colorants, such as curcumin and indigo, as well as modern syntheticmore » colorants such as alizarin lakes and triphenylmethane dyes. Thus, these colorants were selected for further study with emphasis on the nature of the reaction products. Exposures were carried out on different substrates including watercolor paper, cellulose, silica gel, and Teflon. The experiments involved long-term exposure to low levels of ozone (e.g. {approximately} 0.3 ppm for 90 days) or shorter-term exposure to higher ozone concentrations (e.g. 10 ppm for 24 hours). Exposed and control samples, along with solvent and substrate blanks, were analyzed by mass spectrometry using a Kratos Scientific Instruments MS25 hexapole mass spectrometer operated in either methane chemical ionization (CI) or electron impact (EI) modes.« less

40 CFR 51.1103 - Application of classification and attainment date provisions in CAA section 181 of subpart 2 to...

Code of Federal Regulations, 2012 CFR

2012-07-01

... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). 51.1103 Section... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). (a) In... Ozone NAAQS (0.075 ppm) for Areas Subject to Section 51.1102(a) Area class 8-hour design value(ppm ozone...

40 CFR 51.1103 - Application of classification and attainment date provisions in CAA section 181 of subpart 2 to...

Code of Federal Regulations, 2014 CFR

2014-07-01

... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). 51.1103 Section... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). (a) In... Ozone NAAQS (0.075 ppm) for Areas Subject to Section 51.1102(a) Area class 8-hour design value(ppm ozone...

40 CFR 51.1103 - Application of classification and attainment date provisions in CAA section 181 of subpart 2 to...

Code of Federal Regulations, 2013 CFR

2013-07-01

... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). 51.1103 Section... attainment date provisions in CAA section 181 of subpart 2 to areas subject to § 51.1102(a). (a) In... Ozone NAAQS (0.075 ppm) for Areas Subject to Section 51.1102(a) Area class 8-hour design value(ppm ozone...

Ozone reactions with indoor materials during building disinfection

NASA Astrophysics Data System (ADS)

Poppendieck, D.; Hubbard, H.; Ward, M.; Weschler, C.; Corsi, R. L.

There is scant information related to heterogeneous indoor chemistry at ozone concentrations necessary for the effective disinfection of buildings, i.e., hundreds to thousands of ppm. In the present study, 24 materials were exposed for 16 h to ozone concentrations of 1000-1200 ppm in the inlet streams of test chambers. Initial ozone deposition velocities were similar to those reported in the published literature for much lower ozone concentrations, but decayed rapidly as reaction sites on material surfaces were consumed. For every material, deposition velocities converged to a relatively constant, and typically low, value after approximately 11 h. The four materials with the highest sustained deposition velocities were ceiling tile, office partition, medium density fiberboard and gypsum wallboard backing. Analysis of ozone reaction probabilities indicated that throughout each experiment, and particularly after several hours of disinfection, surface reaction resistance dominated the overall resistance to ozone deposition for nearly all materials. Total building disinfection by-products (all carbonyls) were quantified per unit area of each material for the experimental period. Paper, office partition, and medium density fiberboard each released greater than 38 mg m -2 of by-products.

Moderate drought did not affect the effectiveness of ethylenediurea (EDU) in protecting Populus cathayana from ambient ozone.

PubMed

Xin, Yue; Yuan, Xiangyang; Shang, Bo; Manning, William J; Yang, Aizhen; Wang, Younian; Feng, Zhaozhong

2016-11-01

A field study was conducted to evaluate the effects of ambient ozone (O3) on an O3-sensitive poplar (Populus cathayana) by using ethylenediurea (EDU) as a chemical protectant under two soil water treatments (well-watered (WW) and moderate drought (MD, 50-60% of WW in volumetric soil water content). EDU was applied as foliar spray at 0, 300, 450, and 600ppm. Photosynthetic parameters, pigment contents, leaf nitrogen, antioxidant capacity, growth, and biomass were measured. The 8h (9:00-17:00) average ambient O3 concentration was 71.7ppb, and AOT40 was 29.2ppmh during the experimental period (9 June to 21 September), which was high enough to cause plant injury. MD had significantly negative effects on P. cathayana, as indicated by reduced photosynthesis, growth, and biomass, and higher MDA contents. On the other hand, EDU significantly increased photosynthesis rate, chlorophyll a fluorescence, Vcmax and Jmax, photosynthetic pigments, total antioxidant capacity, tree growth and biomass accumulation, and reduced lipid peroxidation, but there was no significant interaction between EDU and drought for most parameters, indicating that EDU can efficiently protect Populus cathayana against ambient O3 and the protection was not affected by soil water contents when soil water reached moderate drought level. Among all doses, EDU at 450ppm provided maximum protection. Comparison of EDU-treated and non-treated P. cathayana could be used as a biomarker system in risk assessment of the effects of ambient O3 on forest health. Copyright © 2016. Published by Elsevier B.V.

Occupational health concerns in the welding industry.

PubMed

Korczynski, R E

2000-12-01

The Workplace Safety and Health Branch initiated a proactive study in the welding industry in Manitoba. Eight welding companies participated in this study. Health concerns raised by welders were welders' flash, sore/red/teary eyes, headaches, nosebleeds, and a black mucous discharge from their nasal membrane. Most welders expressed concern regarding excessive smoke levels in the workplace and inadequate ventilation. Types of welding identified were MIG mild steel, MIG stainless steel, and TIG aluminum. Monitoring involved an assessment of noise levels, fume composition, and carbon monoxide and ozone concentrations. Metal analyses were according to National Institute for Occupational Safety and Health (NIOSH) Method 7300. Noise dosimeters used were the Quest model 100 and Micro 14 & 15. Carbon monoxide was monitored using the Gastech Model 4700 and ozone using the AID Portable Ozone Meter Model 560. In Manitoba, a hearing conservation program is required when the equivalent sound exposure level (normalized Lex 8-hr) exceeds 80 dBA-weighted. The American Conference of Governmental Industrial Hygienists' threshold limit value-time weighted average (ACGIH TLV-TWA) for iron is 5.0 mg/m3, manganese is 0.2 mg/m3, carbon monoxide is 25 ppm, and ozone is 0.05 ppm (heavy work), 0.08 ppm (moderate work), and 0.1 ppm (light work). Welders' personal exposures to manganese ranged from 0.01-4.93 mg/m3 (N = 42; AM = 0.5; GM = 0.2; SD +/- 0.9; GSD +/- 3.2) and to iron ranged from 0.04-16.29 mg/m3 (N = 42; AM = 3.0; GM = 1.4; SD +/- 3.5; GSD +/- 2.5). Noise exposures ranged from 79-98 dBA (N = 44; AM = 88.9; GM = 88.8; SD +/- 4.2; GSD +/- 1.0). Carbon monoxide levels were less than 5.0 ppm (at source) and ozone levels varied from 0.4-0.6 ppm (at source). Ventilation upgrades in the workplace were required in most welding shops. Only 7 percent of the welders wore respiratory protection. A hearing conservation program and hearing protection were required at all monitored workplaces.

Synergistic action of tropospheric ozone and carbon dioxide on yield and nutritional quality of Indian mustard (Brassica juncea (L.) Czern.).

PubMed

Singh, Satyavan; Bhatia, Arti; Tomer, Ritu; Kumar, Vinod; Singh, B; Singh, S D

2013-08-01

Field experiments were conducted in open top chamber during rabi seasons of 2009-10 and 2010-11 at the research farm of the Indian Agricultural Research Institute, New Delhi to study the effect of tropospheric ozone (O3) and carbon dioxide (CO2) interaction on yield and nutritional quality of Indian mustard (Brassica juncea (L.) Czern.). Mustard plants were grown from emergence to maturity under different treatments: charcoal-filtered air (CF, 80-85 % less O3 than ambient O3 and ambient CO2), nonfiltered air (NF, 5-10 % less O3 than ambient O3 and ambient CO2 ), nonfiltered air with elevated carbon dioxide (NF + CO2, NF air and 550 ± 50 ppm CO2), elevated ozone (EO, NF air and 25-35 ppb elevated O3), elevated ozone along with elevated carbon dioxide (EO + CO2, NF air, 25-35 ppb O3 and 550 ± 50 ppm CO2), and ambient chamber less control (AC, ambient O3 and CO2). Elevated O3 exposure led to reduced photosynthesis and leaf area index resulting in decreased seed yield of mustard. Elevated ozone significantly decreased the oil and micronutrient content in mustard. Thirteen to 17 ppm hour O3 exposure (accumulated over threshold of 40 ppm, AOT 40) reduced the oil content by 18-20 %. Elevated CO2 (500 ± 50 ppm) along with EO was able to counter the decline in oil content in the seed, and it increased by 11 to 13 % over EO alone. Elevated CO2, however, decreased protein, calcium, zinc, iron, magnesium, and sulfur content in seed as compared to the nonfiltered control, whereas removal of O3 from air in the charcoal-filtered treatment resulted in a significant increase in the same.

Application of Ozone to Control Dried Fig Pests-Oryzaephilus surinamensis (Coleoptera: Silvanidae) and Ephestia kuehniella (Lepidoptera: Pyralidae)-and Its Organoleptic Properties.

PubMed

Sadeghi, Reza; Mirabi Moghaddam, Rahil; Taghizadeh, Masoud

2017-10-01

Ozone is a powerful oxidant which can be used for killing insects and microorganisms. In this study, ozone was applied in the gaseous form to control two species of pests in stored dried figs. The samples of figs (50 g each) were infested with adults of Oryzaephilus surinamensis L. and larvae of Ephestia kuehniella Zeller and were subjected to different combinations of ozone concentrations (2, 3, and 5 ppm) and exposure times (15, 30, 45, 60, and 90 min). Changes in organoleptic properties (color, sweetness, firmness, aroma, and overall acceptability) during ozonation were studied. The results showed that the mortality rate increased with an increase in ozone concentration and exposure time. The total mortality of both pests was achieved at an ozone concentration of 5 ppm and exposure time of 90 min. Sensory evaluation showed that ozone only had a negligible effect on aroma. Therefore, the usage of ozone is recommended during the postharvest process instead of other chemical fumigants, such as methyl bromide and phosphine. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Inactivation of Human Norovirus and Its Surrogates on Alfalfa Seeds by Aqueous Ozone.

PubMed

Wang, Qing; Markland, Sarah; Kniel, Kalmia E

2015-08-01

Alfalfa sprouts have been associated with numerous foodborne outbreaks. Previous studies investigated the effectiveness of aqueous ozone on bacterially contaminated seeds, yet little is known about the response of human norovirus (huNoV). This study assessed aqueous ozone for the disinfection of alfalfa seeds contaminated with huNoV and its surrogates. The inactivation of viruses without a food matrix was also investigated. Alfalfa seeds were inoculated with huNoV genogroup II, Tulane virus (TV), and murine norovirus (MNV); viruses alone or inoculated on seeds were treated in deionized water containing 6.25 ppm of aqueous ozone with agitation at 22°C for 0.5, 1, 5, 15, or 30 min. The data showed that aqueous ozone resulted in reductions of MNV and TV infectivity from 1.66 ± 1.11 to 5.60 ± 1.11 log PFU/g seeds; for all treatment times, significantly higher reductions were observed for MNV (P < 0.05). Viral genomes were relatively resistant, with a reduction of 1.50 ± 0.14 to 3.00 ± 0.14 log genomic copies/g seeds; the reduction of TV inoculated in water was similar to that of huNoV, whereas MNV had significantly greater reductions in genomic copies (P < 0.05). Similar trends were observed in ozone-treated viruses alone, with significantly higher levels of inactivation (P < 0.05), especially with reduced levels of infectivity for MNV and TV. The significant inactivation by aqueous ozone indicates that ozone may be a plausible substitute for chlorine as an alternative treatment for seeds. The behavior of TV was similar to that of huNoV, which makes it a promising surrogate for these types of scenarios.

Pulmonary Function Response to Exposure to Low Concentration Ozone in Young Adults: Inter-comparison among Studies and Meta-Analysis

EPA Science Inventory

Rationale: It is well established that moderate ozone exposures induce decrements in spirometry volume and respiratory symptoms in healthy young adults. However, studies for low concentration ozone near the current NAAQS standard (0.070 ppm) are limited to only a few and their co...

Low level ozone exposure induces airways inflammation and modifies cell surface phenotypes in healthy humans

EPA Science Inventory

Background: The effects of low level ozone exposure (0.08 ppm) on pulmonary function in healthy young adults are well known, however much less is known about the inflammatory and immuno-modulatory effects oflow level ozone in the airways. Techniques such as induced sputum and flo...

Effects of environmental ozone on the lung function of senior citizens

NASA Astrophysics Data System (ADS)

Höppe, Peter; Lindner, Jutta; Praml, Georg; Brönner, Norman

1995-09-01

Measurements with a body plethysmograph of lung function parameters and reports of unusual complaints or irritations were taken from 41 senior citizens in the situations where they usually spend their daytime hours. The subjects belonged to a group commonly assumed to be at risk from ozone. Each subject was examined on 8 days both in the morning and in the afternoon. The object was to obtain for every subject an equal distribution of measuring days between those with elevated ozone concentrations (maximum 0.5 h mean values between 1.00 and 4.00 p.m. of at least 0.050 ppm) and those with low ozone concentrations (maximum 0.5 h mean values between 1.00 and 4.00 p.m. of at most 0.040 ppm). The results showed no relevant ozone related effects on the lung function parameters or the subjective reports of irritations. Thus there was no indication that senior citizens represent a group at particular risk with respect to moderately elevated concentrations of environmental ozone, as occur in central Europe.

Efficacy and fumigation characteristics of ozone in stored maize.

PubMed

Kells, S A.; Mason, L J.; Maier, D E.; Woloshuk, C P.

2001-10-01

This study evaluated the efficacy of ozone as a fumigant to disinfest stored maize. Treatment of 8.9tonnes (350bu) of maize with 50ppm ozone for 3d resulted in 92-100% mortality of adult red flour beetle, Tribolium castaneum (Herbst), adult maize weevil, Sitophilus zeamais (Motsch.), and larval Indian meal moth, Plodia interpunctella (Hübner) and reduced by 63% the contamination level of the fungus Aspergillus parasiticus Speare on the kernel surface. Ozone fumigation of maize had two distinct phases. Phase 1 was characterized by rapid degradation of the ozone and slow movement through the grain. In Phase 2, the ozone flowed freely through the grain with little degradation and occurred once the molecular sites responsible for ozone degradation became saturated. The rate of saturation depended on the velocity of the ozone/air stream. The optimum apparent velocity for deep penetration of ozone into the grain mass was 0.03m/s, a velocity that is achievable in typical storage structures with current fans and motors. At this velocity 85% of the ozone penetrated 2.7m into the column of grain in 0.8d during Phase 1 and within 5d a stable degradation rate of 1ppm/0.3m was achieved. Optimum velocity for Phase 2 was 0.02m/s. At this velocity, 90% of the ozone dose penetrated 2.7m in less than 0.5d. These data demonstrate the potential usefulness of using ozone in managing stored maize and possibly other grains.

Acute effects of 0. 2 ppm ozone in patients with chronic obstructive pulmonary disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Solic, J.J.; Hazucha, M.J.; Bromberg, P.A.

1982-06-01

Epidemiologic data suggest that patients with chronic obstructive pulmonary disease (COPD) might be more sensitive than normal persons to the respiratory effects of oxidant pollutant exposure. Our study was designed to determine the response of patients with COPD to ozone. Thirteen white men with nonreversible airways obstruction (mean FEV1/FVC, 58%), of whom 8 were current smokers, were randomly exposed for 2 h to air and to 0.2 ppm ozone on 2 consecutive days using a single-blind crossover design. During either exposure, subjects exercised for 7.5 min every 30 min. Measures of respiratory mechanics obtained pre-exposure and postexposure were not significantlymore » affected by either exposure. Similarly, ventilation and gas exchange measured during exercise showed no difference either between exercise periods or exposure days. However, arterial O/sub 2/ saturation (SaO/sub 2/), measured by ear oximetry during the final exercise period each day was lower (94.8%) at the end of O/sub 2/ exposure, than SaO/sub 2/ obtained at the end of air exposure (95.3%), the difference (0.48%) being significant (p . 0.008). Because normal subjects undergoing comparable exposures show a threshold for respiratory mechanical effects at about 0.3 ppm ozone, our data suggest that mild to moderate COPD is not associated with increased sensitivity to low ozone concentrations. However, our data do not rule out the possibility that the response of such subjects might be exaggerated at higher ozone concentrations. The consistent (in 11 of 13 subjects), though small, decrease in SaO/sub 2/ may indicate that indexes of ventilation/perfusion distribution might be more sensitive measures of ozone effect in this compromised patient group than are conventional respiratory mechanics measures.« less

Ozone killing action against bacterial and fungal species; microbiological testing of a domestic ozone generator.

PubMed

Dyas, A; Boughton, B J; Das, B C

1983-10-01

The action of ozone generated from a small domestic device was examined with a view to using it in clinical isolation units accommodating immunosuppressed patients. Over a six-hour period in an average size room the device did not generate sufficient ozone to suppress bacterial and fungal growth. A useful bactericidal action, against a variety of human pathogens was achieved with ozone concentrations between 0.3 to 0.9 ppm. Bactericidal ozone concentrations are close to the limit permitted for human exposure however and further experiments are indicated.

75 FR 958 - Approval and Promulgation of Air Quality Implementation Plans; Maryland; 2002 Base Year Emission...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-07

... standard would be more protective of human health, especially children and adults who are active outdoors... 1997, EPA revised the health-based NAAQS for ozone, setting it at 0.08 parts per million (ppm) averaged... that ozone causes adverse health effects at lower ozone concentrations and over longer periods of time...

75 FR 2091 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-14

... computed 3-year average ozone concentration of 0.085 ppm is the smallest value that is greater than 0.08..., April 30, 1992; 3. ``Contingency Measures for Ozone and Carbon Monoxide (CO) Redesignations... includes contingency measures to remedy future violations of the 1997 8-hour ozone NAAQS. The maintenance...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bolton, D.C.; Zee, Y.C.; Osebold, J.W.

In an effort to establish the biological relevance of the reactions of ozone with soluble proteins and lipid bilayer membrane systems, representative viruses from five major virus groups were exposed to moderate concentrations of ozone. The virus suspensions were exposed at 37/sup 0/C to 0.00, 0.16, and 0.64 ppm ozone in the gas phase. The ozone reacted with the virus suspensions as a thin film of fluid on the surface of a rotating culture bottle as the gas was drawn through the bottle at a flow rate of 2 liters/min. The three enveloped viruses tested exhibited different susceptibilities to ozonemore » inactivation which correlated with their thermolability in the absence of ozone. The order of susceptibility to ozone inactivation of the enveloped viruses was vesicular stomatitis virus (VSV) (Rhabdoviridae) > influenza A virus (WSN strain) (Orthomyxoviridae) > infectious bovine rhinotracheitis virus (IBRV) (Herpesviridae). The inactivation reactions of the enveloped viruses with ozone showed pseudo-first-order kinetics. A simple reaction model was used to derive a reaction rate expression from which rate constrants and reaction stoichiometry were estimated. In contrast to the enveloped viruses, the two nonenveloped viruses examined were relatively resistant to ozone inactivation. Polio virus type I (Picornaviridae) was found to be completely resistant to ozone inactivation after 60 hr exposure to either ozone concentration, while infectious canine hepatitis virus (Adenoviridae) showed only slight inactivation after exposure to 0.64 ppm ozone for 66 hr. The significance of these results with regard to the reactions of ozone with cell membranes and other components is discussed.« less

EFFECT OF RAPID SHALLOW BREATHING ON THE DISTRIBUTION OF 18-O-LABELED OZONE REACTION PRODUCT IN THE RESPIRATORY TRACT OF THE RAT

EPA Science Inventory

We examined the effect of breathing pattern on ozone reaction product content within the respiratory tract. Thirty-four anesthetized, maleWistar rats were exposed to oxygen-18 (18O)-labeled ozone at 1.0 ppm for 2 h using a dual-chamber, negative-pressure ventilation system. Fre...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Romieu, I.; Lugo, M.C.; Velasco, S.R.

To determine the acute effects of ozone exposure, the authors conducted a short follow-up study of respiratory illness in a population of 111 preschool children frequently exposed to ozone levels that regularly exceed 0.120 parts per million (ppm). The children attended a private kindergarten in the southwestern part of Mexico City. Parents completed a questionnaire on demographic data, medical history, and potential sources of indoor air pollution. To determine the relation of ozone and respiratory-related school absenteeism, the authors used a logistic regression model for longitudinal data. During the 3-month follow-up, 50% of the children had at least one respiratory-relatedmore » absenteeism period, and 11.7% had two or more. Children exposed for 2 consecutive days to high ozone levels (> or = 0.13 ppm) had a 20% increment in the risk of respiratory illness. For children exposed for 2 consecutive days to a high ozone level and the previous day to low temperature (< or = 5.1 degrees C), the risk reached 40% (odds ratio = 1.44, 95% confidence interval 1.37-1.52). This study suggests that ozone exposure might be positively associated with the risk of respiratory illness in children and that it may have an interactive effect with low temperature exposure.« less

Relation of pulmonary responses induced by 6.6-h exposures to 0.08 ppm ozone and 2-h exposures to 0.30 ppm ozone via chamber and face-mask inhalation.

PubMed

Adams, William C

2003-07-01

While direct comparison of pulmonary responses to 6.6-h exposures to 0.08 to 0.12 ppm ozone O3 have demonstrated that chamber and face-mask inhalation methods yield closely similar results, no comparative study of responses to 2-h intermittent exercise (IE) exposures to higher O3 concentrations have been reported. The present study was designed to achieve three primary objectives: (1) to compare pulmonary function and symptoms effects of a 2-h IE exposure to 0.30 ppm O3 via chamber and via face mask; (2) to compare the pulmonary effects of 6.6-h chamber exposure to 0.08 ppm O3 to those observed in 2-h IE 0.30 ppm O3 exposures via chamber and via face mask; and (3) to examine filtered air (FA) recovery pulmonary and symptoms responses following chamber exposures of 6.6 h to 0.08 ppm O3 and 2 h to 0.30 ppm O3. A simple regression of postexposure percent change in FEV(1.0) for the 2-h IE, 0.30-ppm O3 chamber exposure as a function of postexposure percent change in FEV(1.0) for the 2-h IE, 0.30-ppm O3 exposure with face mask yielded an R(2) of 0.83. Further, a regression of the postexposure FEV(1.0) response to the chamber 6.6-h, 0.08-ppm O3 exposure as a function of postexposure FEV(1.0) response to the face mask 2-h IE, 0.30-ppm O3 exposure (R(2) of 0.34) was similar to the 0.40 value obtained for the two chamber exposures FEV(1.0) response comparison. Results of the 1.4-h FA recovery following the two chamber O3 exposures showed different rates of FEV(1.0) and symptoms rectification that appeared related to the total O3 dose (product of O3 concentration, ventilation rate, and duration). More data are needed to clarify short-term recovery of O3-induced pulmonary effects and how they may be related to the more abundant data available on the delayed recovery of pulmonary function seen over longer time periods, such as 24 h.

Field responses of Prunus serotina and Asclepias syriaca to ozone around southern Lake Michigan

USGS Publications Warehouse

Bennett, J.P.; Jepsen, E.A.; Roth, J.A.

2006-01-01

Higher ozone concentrations east of southern Lake Michigan compared to west of the lake were used to test hypotheses about injury and growth effects on two plant species. We measured approximately 1000 black cherry trees and over 3000 milkweed stems from 1999 to 2001 for this purpose. Black cherry branch elongation and milkweed growth and pod formation were significantly higher west of Lake Michigan while ozone injury was greater east of Lake Michigan. Using classification and regression tree (CART) analyses we determined that departures from normal precipitation, soil nitrogen and ozone exposure/peak hourly concentrations were the most important variables affecting cherry branch elongation, and milkweed stem height and pod formation. The effects of ozone were not consistently comparable with the effects of soil nutrients, weather, insect or disease injury, and depended on species. Ozone SUM06 exposures greater than 13 ppm-h decreased cherry branch elongation 18%; peak 1-h exposures greater than 93 ppb reduced milkweed stem height 13%; and peak 1-h concentrations greater than 98 ppb reduced pod formation 11% in milkweed. Decreased cherry branch elongation, milkweed stem height and pod production, and foliar injury on both species occurred at sites around southern Lake Michigan at ozone exposures of 13 SUM06 ppm-h and 93a??98 ppb peak hourly.

Interleukin(IL)-1 Regulates Ozone-enhanced Tracheal Smooth Muscle Responsiveness by Increasing Substance P (SP) Production in Intrinsic Airway Neurons of Ferret

PubMed Central

Wu, Z.-X.; Barker, J. S.; Batchelor, T. P.; Dey, R.D.

2008-01-01

Exposure to ozone induces airway hyperresponsiveness (AHR) mediated partly by SP released from nerve terminals of intrinsic airway neurons. Our recent studies showed that IL-1, an important multifunctional proinflammatory cytokine, increases synthesis and release of SP from intrinsic airway neurons. The purpose of this study is to investigate the possible involvement of endogenous IL-1 in modulating neural responses associated with ozone-enhanced airway responsiveness. Ferrets were exposed to 2 ppm ozone or filtered air for 3 hrs. IL-1 in the bronchoalveolar lavage (BAL) fluid was significantly increased in ozone-exposed animals and responses of tracheal smooth muscle to methacholine (MCh) and electrical field stimulation (EFS) were elevated significantly. Both the SP nerve fiber density in tracheal smooth muscle and the number of SP-containing neurons in airway ganglia were significantly increased following ozone exposure. Pretreatment with IL-1 receptor antagonist (IL-1 Ra) significantly diminished ozone-enhanced airway responses to EFS as well as ozone-increased SP in the airway. To selectively investigate intrinsic airway neurons, segments of ferret trachea were maintained in culture conditions for 24 hrs to eliminate extrinsic contributions from sensory nerves. The segments were then exposed to 2 ppm ozone in vitro for 3 hrs. The changes of ozone-induced airway responses to MCh and EFS, and the SP levels in airway neurons paralleled those observed with in vivo ozone exposure. The ozone-enhanced airway responses and neuronal SP levels were inhibited by pretreatment with IL-1 Ra. These findings show that IL-1 is released during ozone exposure enhances airway responsiveness by modulating SP expression in airway neurons. PMID:18718561

Ozone Sensitivity and Catalase Activity in Pigmented and Non-Pigmented Strains of Serratia Marcescens

PubMed Central

de Ondarza, José

2017-01-01

Background: Ozone exposure rapidly leads to bacterial death, making ozone an effective disinfectant in food industry and health care arena. However, microbial defenses may moderate this effect and play a role in the effective use of oxidizing agents for disinfection. Serratia marcescens is an opportunistic pathogen, expressing genes differentially during infection of a human host. A better understanding of regulatory systems that control expression of Serratia’s virulence genes and defenses is therefore valuable. Objective: Here, we investigated the role of pigmentation and catalase in Serratia marcescens on survival to ozone exposure. Method: Pigmented and non-pigmented strains of Serratia marcescens were cultured to exponential or stationary phase and exposed to 5 ppm of gaseous ozone for 2.5 – 10 minutes. Survival was calculated via plate counts. Catalase activity was measured photometrically and tolerance to hydrogen peroxide was assayed by disk-diffusion. Results: Exposure of S. marcescens to 5 ppm gaseous ozone kills > 90% of cells within 10 minutes in a time and concentration-dependent manner. Although pigmented Serratia (grown at 28°C) survived ozonation better than unpigmented Serratia (grown at 35°C), non-pigmented mutant strains of Serratia had similar ozone survival rates, catalase activity and H2O2 tolerance as wild type strains. Rather, ozone survival and catalase activity were elevated in 6 hour cultures compared to 48 hour cultures. Conclusion: Our studies did not bear out a role for prodigiosin in ozone survival. Rather, induction of oxidative stress responses during exponential growth increased both catalase activity and ozone survival in both pigmented and unpigmented S. marcescens. PMID:28567147

Study of air pollution: Effects of ozone on neuropeptide-mediated responses in human subjects. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boushey, H.A.

1991-11-01

The study examined the hypothesis that ozone inactivates the enzyme, neutral endopeptidase, responsible for limiting the effects of neuropeptides released from afferent nerve endings. Cough response of capsaicin solution delivered from a nebulizer at 2 min. intervals until two or more coughs were produced. Other endpoints measured included irritative symptoms as rated by the subjects on a nonparametric scale, spirometry, of each concentration of ozone were compared to those of filtered air in a single-blind randomized sequence. The results indicate that a 2 h. exposure to 0.4 ppm of ozone with intermittent light exercise alters the sensitivity of airway nervesmore » that mediate the cough response to inhaled materials. This dose of ozone also caused a change in FEV1. A lower level of ozone, 0.02 ppm, caused a change in neither cough threshold nor FEV1, even when the duration of exposure was extended to three hours. The findings are consistent with the author's hypothesis that ozone may sensitize nerve endings in the airways by inactivating neutral endopeptidase, an enzyme that regulates their activity, but they do not demonstrate that directly examining an effect directly mediated by airway nerves allows detection of effects of ozone at doses below those causing effects detected by standard tests of pulmonary function.« less

Lagrangian Photochemical Box-Model Calculations of Asian Pacific Rim Outflow During TRACE-P

NASA Astrophysics Data System (ADS)

Hamlin, A.; Crawford, J.; Olson, J.; Avery, M.; Sachse, G.; Barrick, J.; Blake, D.; Tan, D.; Sandholm, S.; Kondo, Y.; Singh, H.; Eisele, F.; Zondlo, M.; Flocke, F.; Talbot, R.

2006-12-01

NASA's TRACE-P (TRAnsport and Chemical Evolution over the Pacific) mission was conducted over the northwestern Pacific February-April, 2001. During two transit flights across the Pacific, extensive pollution was observed from an Asian outflow event that split into two branches over the central Pacific, one subsiding and moving southward over the central Pacific and the other continuing eastward in the upper troposphere. The subsiding branch was observed as a widespread stagnant pollution layer between 2 and 4 km over the central Pacific during transit flights from Kona, HI to Guam. In this region, high levels of O3 (70 ppbv), CO (217 ppbv), and NOx (114 pptv) were well in excess of typical values observed during TRACE-P along the Asian coast. Evidence suggests that the subsiding branch experienced extensive photochemical processing compared to the branch that remained at altitude. To examine the processes controlling the chemical evolution of ozone and its precursors in this outflow event, data collected during the TRACE-P mission have been combined with lagrangian photochemical box model calculations. One of the largest sources of uncertainty in these calculations was associated with predicted water vapor levels along the transport trajectories calculated using the HYSPLIT model. Water vapor levels predicted by HYSPLIT trajectory calculations in the subsiding layer ranged from 3390 to 4880 ppm, while the median level observed in the pollution layer was only 637 ppm. Simulations of ozone production and associated radical chemistry differed dramatically when using water vapor levels based on trajectory calculations versus observed water vapor levels. Levels of PAN and HO2NO2, NOx reservoir species, are also influenced by uncertainties in temperature along the trajectories. These results highlight the importance of accurately representing the humidification and warming of subsiding air masses in 3-D chemical- transport models.

An Evaluation of the Antimicrobial Effects of Gas-Phase Ozone

EPA Science Inventory

This project evaluated the effects of exposing a variety of microorganisms on porous and non-porous materials to elevated gaseous ozone concentrations ranging from 100 - 1000 ppm. Gypsum wallboard (porous) and glass slide (non-porous) building materials were used. Two fungi organ...

Ozone-induced impairment of mucociliary transport and its prevention with N-acetylcysteine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allegra, L.; Moavero, N.E.; Rampoldi, C.

1991-09-30

The effects of an oxidizing gaseous pollutant on tracheal mucous velocity have been studied in conscious sheep. Acute (2 hours) exposure to 1.0 ppm of ozone showed an effect on tracheal mucous velocity that resulted in a significant decrease 40 minutes and 2 hours after exposure (35% and 40% of the baseline, respectively). Repeated exposure for longer periods (4 days, 5 hours/day) to 1.0 ppm of ozone also significantly decreased tracheal mucous velocity during the first and the second day (-47% and -70% of the baseline, respectively), but during the following days of exposure adaptation took place (tracheal mucous velocitymore » ranging from -42% to -55% of baseline). The tracheal mucous velocity still significantly decreased 5 days after the last exposure. N-Acetylcysteine, known both for its mucolytic and antioxidizing properties, has been demonstrated to prevent significantly all of the immediate effects of either short-term or long-term ozone exposures on mucociliary functions.« less

Effect of ozone on penicillium mold decay and sporulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harding, P.R. Jr.

1968-03-01

Tests were run with ozone in the atmosphere of storage rooms that contained oranges and lemons in open wooden storage boxes and in fiberboard cartons. Excellent control of sporulation and some control of decay by Penicillium molds resulted in the open storage boxes with ozone at the 1.0 ppm level, but little control of sporulation and no control of decay resulted in vented cartons held in this concentration. Ozone gave no control of sporulation or decay in nonvented cartons. 6 references, 3 tables.

Inactivation of enterohemorrhagic Escherichia coli in rumen content- or feces-contaminated drinking water for cattle.

PubMed

Zhao, Tong; Zhao, Ping; West, Joe W; Bernard, John K; Cross, Heath G; Doyle, Michael P

2006-05-01

Cattle drinking water is a source of on-farm Escherichia coli O157:H7 transmission. The antimicrobial activities of disinfectants to control E. coli O157:H7 in on-farm drinking water are frequently neutralized by the presence of rumen content and manure that generally contaminate the drinking water. Different chemical treatments, including lactic acid, acidic calcium sulfate, chlorine, chlorine dioxide, hydrogen peroxide, caprylic acid, ozone, butyric acid, sodium benzoate, and competing E. coli, were tested individually or in combination for inactivation of E. coli O157:H7 in the presence of rumen content. Chlorine (5 ppm), ozone (22 to 24 ppm at 5 degrees C), and competing E. coli treatment of water had minimal effects (<1 log CFU/ml reduction) on killing E. coli O157:H7 in the presence of rumen content at water-to-rumen content ratios of 50:1 (vol/wt) and lower. Four chemical-treatment combinations, including (i) 0.1% lactic acid, 0.9% acidic calcium sulfate, and 0.05% caprylic acid (treatment A); (ii) 0.1% lactic acid, 0.9% acidic calcium sulfate, and 0.1% sodium benzoate (treatment B); (iii) 0.1% lactic acid, 0.9% acidic calcium sulfate, and 0.5% butyric acid (treatment C); and (iv) 0.1% lactic acid, 0.9% acidic calcium sulfate, and 100 ppm chlorine dioxide (treatment D); were highly effective (>3 log CFU/ml reduction) at 21 degrees C in killing E. coli O157:H7, O26:H11, and O111:NM in water heavily contaminated with rumen content (10:1 water/rumen content ratio [vol/wt]) or feces (20:1 water/feces ratio [vol/wt]). Among them, treatments A, B, and C killed >5 log CFU E. coli O157:H7, O26:H11, and O111:NM/ml within 30 min in water containing rumen content or feces, whereas treatment D inactivated approximately 3 to 4 log CFU/ml under the same conditions. Cattle given water containing treatment A or C or untreated water (control) ad libitum for two 7-day periods drank 15.2, 13.8, and 30.3 liters/day, respectively, and cattle given water containing 0.1% lactic acid plus 0.9% acidic calcium sulfate (pH 2.1) drank 18.6 liters/day. The amounts of water consumed for all water treatments were significantly different from that for the control, but there were no significant differences among the water treatments. Such treatments may best be applied periodically to drinking water troughs and then flushed, rather than being added continuously, to avoid reduced water consumption by cattle.

Flight crew exposure to ozone concentrations affecting the visual system.

PubMed

Daubs, J

1980-02-01

To estimate the potential for ozone (O3) effects on the human visual system in flight, O3 concentrations in Boeing 747-100 cockpits were measured during routine flights between London and the United States. From a review of previous reports, it appears that O3 may have both beneficial and harmful effects but that further studies of the visual system responses to O3 are needed before the present findings of 0.030 parts per million (ppm) mean O3, 0.200 ppm maximum O3, and 0.261 ppm-hours average cumulative O3 exposure can be effectively evaluated. Unexpectedly high O3 concentrations were encountered at altitudes below 18,000 feet and, at times, the O3 concentration was observed to decrease as flight level was increased. The clinical, operational, and policy implications of these findings are discussed.

Systemic metabolic derangement, pulmonary effects, and insulin insufficiency following subchronic ozone exposure in rats.

PubMed

Miller, Desinia B; Snow, Samantha J; Henriquez, Andres; Schladweiler, Mette C; Ledbetter, Allen D; Richards, Judy E; Andrews, Debora L; Kodavanti, Urmila P

2016-09-01

Acute ozone exposure induces a classical stress response with elevated circulating stress hormones along with changes in glucose, protein and lipid metabolism in rats, with similar alterations in ozone-exposed humans. These stress-mediated changes over time have been linked to insulin resistance. We hypothesized that acute ozone-induced stress response and metabolic impairment would persist during subchronic episodic exposure and induce peripheral insulin resistance. Male Wistar Kyoto rats were exposed to air or 0.25ppm or 1.00ppm ozone, 5h/day, 3 consecutive days/week (wk) for 13wks. Pulmonary, metabolic, insulin signaling and stress endpoints were determined immediately after 13wk or following a 1wk recovery period (13wk+1wk recovery). We show that episodic ozone exposure is associated with persistent pulmonary injury and inflammation, fasting hyperglycemia, glucose intolerance, as well as, elevated circulating adrenaline and cholesterol when measured at 13wk, however, these responses were largely reversible following a 1wk recovery. Moreover, the increases noted acutely after ozone exposure in non-esterified fatty acids and branched chain amino acid levels were not apparent following a subchronic exposure. Neither peripheral or tissue specific insulin resistance nor increased hepatic gluconeogenesis were present after subchronic ozone exposure. Instead, long-term ozone exposure lowered circulating insulin and severely impaired glucose-stimulated beta-cell insulin secretion. Thus, our findings in young-adult rats provide potential insights into epidemiological studies that show a positive association between ozone exposures and type 1 diabetes. Ozone-induced beta-cell dysfunction may secondarily contribute to other tissue-specific metabolic alterations following chronic exposure due to impaired regulation of glucose, lipid, and protein metabolism. Published by Elsevier Inc.

Systemic metabolic derangement, pulmonary effects, and insulin insufficiency following subchronic ozone exposure in rats☆,☆☆

PubMed Central

Miller, Desinia B.; Snow, Samantha J.; Henriquez, Andres; Schladweiler, Mette C.; Ledbetter, Allen D.; Richards, Judy E.; Andrews, Debora L.; Kodavanti, Urmila P.

2017-01-01

Acute ozone exposure induces a classical stress response with elevated circulating stress hormones along with changes in glucose, protein and lipid metabolism in rats, with similar alterations in ozone-exposed humans. These stress-mediated changes over time have been linked to insulin resistance. We hypothesized that acute ozone-induced stress response and metabolic impairment would persist during subchronic episodic exposure and induce peripheral insulin resistance. Male Wistar Kyoto rats were exposed to air or 0.25 ppm or 1.00 ppm ozone, 5 h/day, 3 consecutive days/week (wk) for 13 wks. Pulmonary, metabolic, insulin signaling and stress endpoints were determined immediately after 13 wk or following a 1 wk recovery period (13 wk + 1 wk recovery). We show that episodic ozone exposure is associated with persistent pulmonary injury and inflammation, fasting hyperglycemia, glucose intolerance, as well as, elevated circulating adrenaline and cholesterol when measured at 13 wk, however, these responses were largely reversible following a 1 wk recovery. Moreover, the increases noted acutely after ozone exposure in non-esterified fatty acids and branched chain amino acid levels were not apparent following a subchronic exposure. Neither peripheral or tissue specific insulin resistance nor increased hepatic gluconeogenesis were present after subchronic ozone exposure. Instead, long-term ozone exposure lowered circulating insulin and severely impaired glucose-stimulated beta-cell insulin secretion. Thus, our findings in young-adult rats provide potential insights into epidemiological studies that show a positive association between ozone exposures and type 1 diabetes. Ozone-induced beta-cell dysfunction may secondarily contribute to other tissue-specific metabolic alterations following chronic exposure due to impaired regulation of glucose, lipid, and protein metabolism. PMID:27368153

Real-time monitoring of ozone in air using substrate-integrated hollow waveguide mid-infrared sensors

NASA Astrophysics Data System (ADS)

da Silveira Petruci, João Flávio; Fortes, Paula Regina; Kokoric, Vjekoslav; Wilk, Andreas; Raimundo, Ivo Milton; Cardoso, Arnaldo Alves; Mizaikoff, Boris

2013-11-01

Ozone is a strong oxidant that is globally used as disinfection agent for many purposes including indoor building air cleaning, during food preparation procedures, and for control and killing of bacteria such as E. coli and S. aureus. However, it has been shown that effective ozone concentrations for controlling e.g., microbial growth need to be higher than 5 ppm, thereby exceeding the recommended U.S. EPA threshold more than 10 times. Consequently, real-time monitoring of such ozone concentration levels is essential. Here, we describe the first online gas sensing system combining a compact Fourier transform infrared (FTIR) spectrometer with a new generation of gas cells, a so-called substrate-integrated hollow waveguide (iHWG). The sensor was calibrated using an UV lamp for the controlled generation of ozone in synthetic air. A calibration function was established in the concentration range of 0.3-5.4 mmol m-3 enabling a calculated limit of detection (LOD) at 0.14 mmol m-3 (3.5 ppm) of ozone. Given the adaptability of the developed IR sensing device toward a series of relevant air pollutants, and considering the potential for miniaturization e.g., in combination with tunable quantum cascade lasers in lieu of the FTIR spectrometer, a wide range of sensing and monitoring applications of beyond ozone analysis are anticipated.

PREDICTING THE REGIONAL IMPACT OF OZONE AND PRECIPITATION ON THE GROWTH OF LOBLOLLY PINE AND YELLOW-POPLAR USING LINKED TREGRO AND ZELIG MODELS

EPA Science Inventory

To simulate the long-term effects of ozone on forests in the US, we linked TREGRO, a mechanistic model of an individual tree, to ZELIG, a forest stand model, to examine the response of forests to 5 ozone exposure regimes (0 to 100 ppm-hr SUM06 per year) in 100 year simulations. ...

Influence of ozone and HCl gas on citrus and the vesicular-arbuscular mycorrhizal fungus Glomus fasciculatus

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCool, P.M.; Menge, J.A.; Taylor, O.C.

1977-01-01

One half of Troyer citrange (Poncirus trifoliata x Citrus sinensis) seedlings were grown from seed and inoculated during transplanting with Glomus fasciculatus. Inoculum consisted of soil and roots from sudangrass (Sorghum vulgare) containing hyphae, vesicles, arbuscles, and chlamydospores of G. fasciculatus. At 5, 12, and 16 weeks after inoculation, both inoculated and noninoculated seedlings were exposed to 110-140 mg/m/sup 3/ (73-92 ppm) HCl gas for 20 minutes or to 2 mg/m/sup 3/ (1 ppm) ozone for 4 hours. HCl produced moderate marginal leaf necrosis while ozone produced no visible symptoms. Control and HCl-exposed mycorrhizal seedlings were 28% and 36% taller,more » respectively, than corresponding nonmycorrhizal seedlings. Exposure to HCl reduced mycorrhizal seedling height by 24% compared to mycorrhizal controls. Ozone exposed mycorrhizal citrus were not significantly taller than non-mycorrhizal citrus but were 37% shorter than mycorrhizal controls. Total biomass of control and HCl-exposed mycorrhizal seedlings were greater than their nonmycorrhizal counterparts but the biomass was not significantly different between ozone-exposed seedlings. Spore production by G. fasciculatus was reduced 50% in ozone-exposed seedlings while spore populations of HCl-exposed seedlings were not statistically different from the controls.« less

Age-dependent inhibition of pentobarbital sleeping time by ozone in mice and rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Canada, A.T.; Calabrese, E.J.; Leonard, D.

1986-09-01

The effect of age on the metabolism of pentobarbital in mice and rats was investigated following exposure to 0.3 ppm of ozone for 3.75 hr. Young animals were 2.5 months of age and the mature were 18 months. The pentobarbital sleeping time was significantly prolonged following the ozone exposure in both the mice and rats when compared with an air control. No ozone effect on sleeping time was found in the young animals. The results indicate that there may be an age-related sensitivity to the occurrence of ozone-related inhibition of pentobarbital metabolism.

Non-thermal atmospheric pressure HF plasma source: generation of nitric oxide and ozone for bio-medical applications

NASA Astrophysics Data System (ADS)

Kühn, S.; Bibinov, N.; Gesche, R.; Awakowicz, P.

2010-01-01

A new miniature high-frequency (HF) plasma source intended for bio-medical applications is studied using nitrogen/oxygen mixture at atmospheric pressure. This plasma source can be used as an element of a plasma source array for applications in dermatology and surgery. Nitric oxide and ozone which are produced in this plasma source are well-known agents for proliferation of the cells, inhalation therapy for newborn infants, disinfection of wounds and blood ozonation. Using optical emission spectroscopy, microphotography and numerical simulation, the gas temperature in the active plasma region and plasma parameters (electron density and electron distribution function) are determined for varied nitrogen/oxygen flows. The influence of the gas flows on the plasma conditions is studied. Ozone and nitric oxide concentrations in the effluent of the plasma source are measured using absorption spectroscopy and electro-chemical NO-detector at variable gas flows. Correlations between plasma parameters and concentrations of the particles in the effluent of the plasma source are discussed. By varying the gas flows, the HF plasma source can be optimized for nitric oxide or ozone production. Maximum concentrations of 2750 ppm and 400 ppm of NO and O3, correspondingly, are generated.

Effect of 2 ppm ozone exposure on rat lung lipid fatty acids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rabinowitz, J.L.; Bassett, D.J.

Based on in vitro studies, the initial damage to lung cells by ozone exposure is believed to result in part from the breakdown of lipid polyunsaturated fatty acids to aldehydes, ozonides, and peroxides. The present study measured lipid breakdown products in lungs isolated from rats pretreated with (1-/sup 14/C)acetate 12 h before exposure for 4 h to either air or 2 ppm ozone. Lipid fatty acid breakdown was indicated by a 112% increase in thiobarbituric acid-reactive substances on ozone exposure and by changes in chemical and radioactive measurements of mono- and dicarboxylic acids formed by treatment of lipid fractions withmore » hydrogen peroxide. Ozone exposure resulted in a 63% increase in recovery of short-chain fatty acids accounted for by increased recoveries of malonic acid by 37%, hexanoic acid by 47%, nonanoic acid by 118%, and azelaic acid by 107%. Recovery of glutaric acid was enhanced 15-fold by ozone exposure. Although decreases in tissue arachidonic acid could not be detected, oleic acid was significantly decreased by 36%. Recovery of radiolabel as short-chain fatty acids was increased by 65% on ozone exposure and was mainly accounted for by enhanced labeling of nonanoic and glutaric acid fractions. The failure to observe significant increases in /sup 14/C recovery in the other fractions suggested ozone-induced breakdown of unlabeled fatty acids. These results demonstrate the cleavage of unsaturated fatty acid double bonds following in vivo exposure of lungs to ozone. Breakdown of arachidonic and oleic acids was specifically identified by increased recoveries of glutaric and nonanoic acids, respectively.« less

Fate of Pathologically Bound Oxygen Resulting from Inhalation of Labeled Ozone in Rats

PubMed Central

Hatch, Gary E.; Slade, Ralph; McKee, John

2013-01-01

Inhaled ozone (O3) reacts chemically with respiratory tract biomolecules where it forms covalently bound oxygen adducts. We investigated the fate of these adducts following inhalation exposure of rats to labeled ozone (18O3, 2 ppm, 6 hr or 5 ppm, 2 hr). Increased 18O was detected in blood plasma at 7 hr post exposure and was continuously present in urine for 4 days. Total 18O excreted was ~53% of the estimated amount of 18O3 retained by the rats during 18O3 exposure suggesting that only moderate recycling of the adduct material occurs. The time course of excretion, as well as properties of the excreted 18O were determined to provide guidance to future searches for urinary oxidative stress markers. These results lend plausibility to published findings that O3 inhalation could exert influences outside the lung, such as enhancement of atherosclerotic plaques. PMID:24052692

Oxidized lipids and lipid-mediators are involved in cardiovascular injury induced by diesel exhaust particles and ozone

EPA Science Inventory

The mechanisms by which air pollutants induce cardiac and vascular injuries are unknown. We hypothesized that these injuries involve alterations in'aortic membrane lipids and lipid-mediators. We exposed male Wistar Kyoto rats (12-15 wk old), nose-only to air, ozone (03; 0.5 ppm),...

OZONE UPTAKE IN THE INTACT HUMAN RESPIRATORY TRACT - RELATIONSHIP BETWEEN INHALED AND ACTUAL DOSE

EPA Science Inventory

Inhaled concentration (C), minute volume (MV), and exposure duration (T) are factors that may affect the uptake of ozone (03) within the respiratory tract. Ten healthy adult nonsmokers participated in four sessions, inhaling 0.2 or 0.4 ppm 03 through an oral mask while exercisi...

Effect of ozone exposure on seasonal gas exchange of five western conifers

Treesearch

Nancy E. Grulke; Paul R. Miller; Theodor D. Leininger

1998-01-01

Five species of western conifers (Pinus ponderosa, Abies concolor, Pseudotsuga menziesii, Abies lasiocarpa, and Picea engelmannii) were exposed, in two standard open-top exposure chambers per treatment, to charcoal-filtered air and a simulated diurnal ozone exposure profile (120 d sum of 136 ppm-h) to test their relative...

Ozone induces glucose intolerance and systemic metabolic effects in young and aged brown Norway rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bass, V.; Gordon, C.J.; Jarema, K.A.

Air pollutants have been associated with increased diabetes in humans. We hypothesized that ozone would impair glucose homeostasis by altering insulin signaling and/or endoplasmic reticular (ER) stress in young and aged rats. One, 4, 12, and 24 month old Brown Norway (BN) rats were exposed to air or ozone, 0.25 or 1.0 ppm, 6 h/day for 2 days (acute) or 2 d/week for 13 weeks (subchronic). Additionally, 4 month old rats were exposed to air or 1.0 ppm ozone, 6 h/day for 1 or 2 days (time-course). Glucose tolerance tests (GTT) were performed immediately after exposure. Serum and tissue biomarkersmore » were analyzed 18 h after final ozone for acute and subchronic studies, and immediately after each day of exposure in the time-course study. Age-related glucose intolerance and increases in metabolic biomarkers were apparent at baseline. Acute ozone caused hyperglycemia and glucose intolerance in rats of all ages. Ozone-induced glucose intolerance was reduced in rats exposed for 13 weeks. Acute, but not subchronic ozone increased α{sub 2}-macroglobulin, adiponectin and osteopontin. Time-course analysis indicated glucose intolerance at days 1 and 2 (2 > 1), and a recovery 18 h post ozone. Leptin increased day 1 and epinephrine at all times after ozone. Ozone tended to decrease phosphorylated insulin receptor substrate-1 in liver and adipose tissues. ER stress appeared to be the consequence of ozone induced acute metabolic impairment since transcriptional markers of ER stress increased only after 2 days of ozone. In conclusion, acute ozone exposure induces marked systemic metabolic impairments in BN rats of all ages, likely through sympathetic stimulation. - Highlights: • Air pollutants have been associated with increased diabetes in humans. • Acute ozone exposure produces profound metabolic alterations in rats. • Age influences metabolic risk factors in aging BN rats. • Acute metabolic effects are reversible and repeated exposure reduces these effects. • Ozone metabolic effects are only slightly exacerbated in geriatric rats.« less

Effect of ozone on the microbiological status of five dried aromatic plants.

PubMed

Kazi, Martha; Parlapani, Foteini F; Boziaris, Ioannis S; Vellios, Evangelos K; Lykas, Christos

2018-03-01

Aromatic plants may be contaminated with a wide range of microorganisms, making them a potential health hazard when infused or added to ready-to-eat meals. To ensure safety, the effect of gaseous ozone treatment on the population of aerobic plate counts (APC), hygienic indicators (Escherichia coli, Enterococcus spp. and Enterobacteriaceae) and fungi was investigated for five dried aromatic plants: oregano, thyme, mountain tea, lemon verbena and chamomile. Selection, isolation and further fungi identification were based on the phenotypic and macro- and microscopic characteristics. Prior to ozonation, APC on five dried aromatic plants was in the range 5-7 log colony-forming units (CFU) g -1 . The APC exhibited a 4 log reduction, from around 6.5 to 2.5 in the case of oregano, and only a 1-2 log reduction for other herbs after 30 or 60 min of 4 ppm gaseous ozone treatment. Enterococcus spp. and E. coli were not detected on any of the tested dried aromatic plants. The fungi counts were 2-4 log CFU g -1 before ozonation. Aspergillus spp, Penicillium spp, Cladosporium spp, Alternaria spp, Fusarium spp., Ulocladium spp. and some unknown fungi were detected on plants before ozone treatment. Aspergillus spp. and/or Penicillium spp. were only detected on mountain tea and thyme plant material after 60 min of ozonation. The present study provides information about the efficiency of ozone on the microbial decontamination of dried aromatic plants. Treatment with gaseous ozone at 4 ppm for 30 min in the case of dried oregano and 60 min in the case of chamomile and lemon verbena could be used as alternative disinfection methods. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Systemic metabolic derangement, pulmonary effects, and insulin insufficiency following subchronic ozone exposure in rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Desinia B.

Acute ozone exposure induces a classical stress response with elevated circulating stress hormones along with changes in glucose, protein and lipid metabolism in rats, with similar alterations in ozone-exposed humans. These stress-mediated changes over time have been linked to insulin resistance. We hypothesized that acute ozone-induced stress response and metabolic impairment would persist during subchronic episodic exposure and induce peripheral insulin resistance. Male Wistar Kyoto rats were exposed to air or 0.25 ppm or 1.00 ppm ozone, 5 h/day, 3 consecutive days/week (wk) for 13 wks. Pulmonary, metabolic, insulin signaling and stress endpoints were determined immediately after 13 wk ormore » following a 1 wk recovery period (13 wk + 1 wk recovery). We show that episodic ozone exposure is associated with persistent pulmonary injury and inflammation, fasting hyperglycemia, glucose intolerance, as well as, elevated circulating adrenaline and cholesterol when measured at 13 wk, however, these responses were largely reversible following a 1 wk recovery. Moreover, the increases noted acutely after ozone exposure in non-esterified fatty acids and branched chain amino acid levels were not apparent following a subchronic exposure. Neither peripheral or tissue specific insulin resistance nor increased hepatic gluconeogenesis were present after subchronic ozone exposure. Instead, long-term ozone exposure lowered circulating insulin and severely impaired glucose-stimulated beta-cell insulin secretion. Thus, our findings in young-adult rats provide potential insights into epidemiological studies that show a positive association between ozone exposures and type 1 diabetes. Ozone-induced beta-cell dysfunction may secondarily contribute to other tissue-specific metabolic alterations following chronic exposure due to impaired regulation of glucose, lipid, and protein metabolism. - Highlights: • Subchronic episodic ozone exposure caused pulmonary and metabolic effects. • These effects were largely reversible upon one week recovery. • Ozone exposure did not cause liver or muscle insulin resistance. • Subchronic ozone exposure led to decrease in serum insulin. • Ozone severely impaired beta cell insulin secretion in response to glucose.« less

Environmental Pollutant Ozone Causes Damage to Lung Surfactant Protein B (SP-B)

PubMed Central

2015-01-01

Lung surfactant protein B (SP-B) is an essential protein found in the surfactant fluid at the air–water interface of the lung. Exposure to the air pollutant ozone could potentially damage SP-B and lead to respiratory distress. We have studied two peptides, one consisting of the N-terminus of SP-B [SP-B(1–25)] and the other a construct of the N- and C-termini of SP-B [SP-B(1–25,63–78)], called SMB. Exposure to dilute levels of ozone (∼2 ppm) of monolayers of each peptide at the air–water interface leads to a rapid reaction, which is evident from an increase in the surface tension. Fluorescence experiments revealed that this increase in surface tension is accompanied by a loss of fluorescence from the tryptophan residue at the interface. Neutron and X-ray reflectivity experiments show that, in contrast to suggestions in the literature, the peptides are not solubilized upon oxidation but rather remain at the interface with little change in their hydration. Analysis of the product material reveals that no cleavage of the peptides occurs, but a more hydrophobic product is slowly formed together with an increased level of oligomerization. We attributed this to partial unfolding of the peptides. Experiments conducted in the presence of phospholipids reveal that the presence of the lipids does not prevent oxidation of the peptides. Our results strongly suggest that exposure to low levels of ozone gas will damage SP-B, leading to a change in its structure. The implication is that the oxidized protein will be impaired in its ability to interact at the air–water interface with negatively charged phosphoglycerol lipids, thus compromising what is thought to be its main biological function. PMID:26270023

Inheritance of ozone resistance in tall fescue

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnston, W.J.; Haaland, R.L.; Dickens, R.

Ozone is considered the most important air pollutant affecting vegetation. With progressive urbanization, ozone levels have steadily escalated. Reports suggest that ozone tolerance is a highly heritable characteristic and that the selection of resistant plants and breeding for ozone resistance should be possible. This study was undertaken to gain information on the inheritance of ozone resistance in tall fescue (Festuca arundinacea Schreb.).Progenies from a diallel among six tall fescue genotypes of diverse origin were evaluated for ozone resistance in a fumigation-chamber. Sixteen-day-old seedlings were exposed to 0.5 ppm ozone for 3 hours and scored for injury after 3 days. Generalmore » combining ability (GCA) and reciprocal effects were both highly significant; however, GCA constituted a major portion of the genotypic variation. Specific combining ability was not significant. The predominance of additive genetic variance observed indicates that breeding for ozone resistance in this tall fescue population should be possible.« less

40 CFR 49.137 - Rule for air pollution episodes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... continue or reoccur over the next 24 hours. (A) Particulate matter (PM10): 350 micrograms per cubic meter, 24-hour average; (B) Carbon monoxide (CO): 17 milligrams per cubic meter (15 ppm), 8-hour average; (C) Sulfur dioxide (SO2): 800 micrograms per cubic meter (0.3 ppm), 24-hour average; (D) Ozone (O3): 400...

DISTRIBUTION AND REPRODUCIBILITY OF SPIROMETRIC RESPONSE TO OZONE BY GENDER AND AGE

EPA Science Inventory

Subjects were healthy nonsmoking men (n = 146) and women (n = 94) 18-60 yr old. Initially, each subject was exposed for 1.5 h to 0.42 ppm O3. Forty-seven individuals were later reexposed twice, 1 wk to several months apart, to 0.4 ppm O3. Intermittent exercise utilized in all exp...

COVARIATE MEASUREMENTS FOR INCREASING THE PRECISION OF PLANT RESPONSE TO O3 AND SO2

EPA Science Inventory

Lettuce (Lactuca sativa L. ev. Grand Rapids) and radish (Raphanus sativus L. cv. Cherry Belle) plants growing at baseline environmental conditions were exposed to charcoal-filtered air, 0.40 ppm (v/v) ozone, and 0.80 ppm sulfur dioxide alone or in combination for 6 hours at 14 da...

Pulmonary Responses in Healthy Young Adults Exposed to Low Concentration of Ozone for 6.6 Hours with Mild Exercise

EPA Science Inventory

Rational: Recent studies have shown small but significant decreases in lung function following a prolonged exposure (6.6 hour) of healthy young adults to levels of ozone (0.08 ppm) near the current 8 hour standard. It is unclear, however, if such effects may be extended to concen...

Cardiovascular effects of diesel exhaust and ozone in a multi-pollutant context

EPA Science Inventory

The cardiovascular effects of two common pollutants, diesel exhaust (DE) and ozone (O3), were examined alone and in combination. Healthy subjects (n=15) were exposed for 2 hrs with intermittent, moderate exercise on Day 1 to 0.3 ppm O3, 300 µg/m3 DE, both O3 and DE, or fil...

77 FR 21690 - Approval and Promulgation of Air Quality Implementation Plan for 1997 8-Hour Ozone Standard; Arizona

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-11

... and emissions input data preparation, model performance evaluation, interpreting modeling results, and... standard based on ambient ozone monitoring data for the 2006- 2008 period. EPA has not yet acted on this... ppm) and years thereafter were at or below the standard. See EPA Air Quality System (AQS) data...

Effects of simulated acid rain, ozone and sulfur dioxide on suitability of elms for elm leaf beetle

Treesearch

Richard W. Hall; Jack H. Barger; Alden M. Townsend

1988-01-01

Cuttings from two clonally propagated elm hybrids ('Pioneer' and 'Homestead') were treated with ozone (03), sulfur dioxide (S02), simulated acid rain or left untreated. Fumigants were applied 7 hours per day, 5 days per week for 9 weeks in open-top chambers. Fumigation treatments were: 0.1 ppm 0

Pulmonary function in men after short-term exposure to ozone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hazucha, M.; Silverman, F.; Parent, C.

1973-01-01

Volunteers were exposed to 0.37 or 0.75 ppm ozone for 2 hr in environmental chamber while doing light exercise and resting intermittently. Slight discomfort resulted: dry throat, cough, chest tightness. Reduction in flow rates, FVC, and FEV at 1 and 2 hr was noted. Thus, ozone reached terminal bronchioles and impaired their function. Reduction in pulmonary measurements of maximum flow results were probably due to decreased lung elastic recoil, increased airway resistence, and small airway obstruction.

Carrot injury and yield response to ozone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennett, J.P.; Oshima, R.J.

1976-11-01

Container-grown plants of carrot (Daucus carota L.) exposed intermittently to 0.19 or 0.25 ppm ozone throughout their growth increased in plant height and total number of leaves in spite of the development of chlorotic leaves. Leaf dry weight was unaffected by ozone, but root dry matter decreased 32 to 46%. As a result, the root weight/total dry weight ration and root/shoot ratio declined significantly in the presence of ozone. A regression of root dry weight on chlorotic lead dry weight explained 35% of the root loss and predicted that 1.5 g of root tissue is lost for every g ofmore » chlorotic leaf dry weight casued by ozone injury.« less

Biomarkers of Dose and Effect of inhaled ozone in resting versus exercising human subjects: comparison with resting rats

EPA Science Inventory

Background: Human controlled exposure studies have generally focused on subjects exposed to ozone (O3) while exercising while exposures in rats have been done at rest. We exposed resting subjects to labeled O3 (18O3, 0.4 ppm, for 2 hr) and compared O3 dose and effects with our...

Ozone-induced H2O2 accumulation in field-grown aspen and birch is linked to foliar ultrastructure and peroxisomal activity

Treesearch

E. Oksanen; E. Häikiö; J. Sober; D.F. Karnosky

2003-01-01

Saplings of three aspen (Populus tremuloides) genotypes and seedlings of paper birch (Betula papyrifera) were exposed to elevated ozone (1.5x ambient) and 560 p.p.m. CO2, singly and in combination, from 1998 at the Aspen-FACE (free-air CO2 enrichment) site (Rhinelander, USA).

Comparison of ozone and chlorine in low concentrations as sanitizing agents of chicken carcasses in the water immersion chiller.

PubMed

Trindade, Marco Antonio; Kushida, Marta Mitsui; Montes Villanueva, Nilda D; dos Santos Pereira, David Uenaka; De Oliveira, Andcelso Eduardo Lins

2012-06-01

The aim of this study was to investigate the effects of the use of chlorine or ozone as sanitizing agents in the water of chicken immersion chilling, using the residual levels usually applied in Brazil (1.5 ppm), comparing the effects of these treatments on the microbiological, physicochemical, and sensory characteristics of carcasses. Chicken carcasses were chilled in water (4°C) with similar residual levels of ozone and chlorine until reaching temperatures below 7°C (around 45 min). The stability of carcasses was assessed during 15 days of storage at 2 ± 1°C. Microbiological, surface color (L*, a*, b* parameters), pH value, lipid oxidation (thiobarbituric acid reactive substances index), and sensory evaluation (on a 9-point hedonic scale for odor and appearance) analyses were carried out. The presence of Salmonella was not detected, coagulase-positive staphylococci counts were below 10(2) CFU/ml of rinse fluid, and Escherichia coli and total coliform counts were below 10(5) CFU/ml of rinse fluid until the end of the storage period for both treatments. Psychrotrophic microorganism counts did not differ (P > 0.05) between chlorine and ozone treatments, and both values were near 10(9) CFU/ml of rinse fluid after 15 days at 4 ± 1°C. pH values did not differ between treatments (P > 0.05) or during the storage period (P > 0.05). In addition, neither chlorine nor ozone treatment showed differences (P > 0.05) in the lipid oxidation of carcasses; however, the thiobarbituric acid reactive substances index of both treatments increased (P ≤ 0.05) during the storage period, reaching values of approximately 0.68 mg of malonaldehyde per kg. Samples from both treatments did not differ (P > 0.05) in their acceptance scores for odor and overall appearance, but in the evaluation of color, ozone showed an acceptance score significantly higher (P ≤ 0.05) than that for the chlorine treatment. In general, under the conditions tested, ozone showed results similar to the results for chlorine in the disinfection of chicken carcasses in the immersion chilling, which may indicate its use as a substitute for chlorine in poultry slaughterhouses.

Ozone dose-response relationships for spring oilseed rape and broccoli

NASA Astrophysics Data System (ADS)

De Bock, Maarten; Op de Beeck, Maarten; De Temmerman, Ludwig; Guisez, Yves; Ceulemans, Reinhart; Vandermeiren, Karine

2011-03-01

Tropospheric ozone is an important air pollutant with known detrimental effects for several crops. Ozone effects on seed yield, oil percentage, oil yield and 1000 seed weight were examined for spring oilseed rape ( Brassica napus cv. Ability). For broccoli ( Brassica oleracea L. cv. Italica cv. Monaco) the effects on fresh marketable weight and total dry weight were studied. Current ozone levels were compared with an increase of 20 and 40 ppb during 8 h per day, over the entire growing season. Oilseed rape seed yield was negatively correlated with ozone dose indices calculated from emergence until harvest. This resulted in an R2 of 0.24 and 0.26 ( p < 0.001) for the accumulated hourly O 3 exposure over a threshold of 40 ppb (AOT40) and the phytotoxic ozone dose above a threshold of 6 nmol m -2 s -1 (POD 6) respectively. Estimated critical levels, above which 5% yield reduction is expected, were 3.7 ppm h and 4.4 mmol m -2 respectively. Our results also confirm that a threshold value of 6 nmol s -1 m -2 projected leaf area, as recommended for agricultural crops (UNECE, Mills, 2004), can indeed be applied for spring oilseed rape. The reduction of oilseed rape yield showed the highest correlation with the ozone uptake during the vegetative growth stage: when only the first 47 days after emergence were used to calculate POD 6, R2 values increased up to 0.476 or even 0.545 when the first 23 days were excluded. The highest ozone treatments, corresponding to the future ambient level by 2100 (IPCC, Meehl et al., 2007), led to a reduction of approximately 30% in oilseed rape seed yield in comparison to the current ozone concentrations. Oil percentage was also significantly reduced in response to ozone ( p < 0.001). As a consequence oil yield was even more severely affected by elevated ozone exposure compared to seed yield: critical levels for oil yield dropped to 3.2 ppm h and 3.9 mmol m -2. For broccoli the applied ozone doses had no effect on yield.

Effects of ozone and sulfur dioxide on height and stem specific gravity of Populus hybrids

Treesearch

Roy L. Patton

1981-01-01

Unfumigated hybrid poplars (Populus spp.) were compared with poplars of the same nine clones fumigated with 0.15 pprn ozone or 0.25 ppm sulfur dioxide. After 102 days, plant height and stem specific gravity were measured to determine whether specific gravity is altered by the fumigants and to compare that response to height suppression, an accepted...

In-Line Ozonation for Sensitive Air-Monitoring of a Mustard-Gas Simulant by Atmospheric Pressure Chemical Ionization Mass Spectrometry

NASA Astrophysics Data System (ADS)

Okumura, Akihiko

2015-09-01

A highly sensitive method for real-time air-monitoring of mustard gas (bis(2-chloroethyl) sulfide, HD), which is a lethal blister agent, is proposed. Humidified air containing a HD simulant, 2-chloroethyl ethyl sulfide (2CEES), was mixed with ozone and then analyzed by using an atmospheric pressure chemical ionization ion trap tandem mass spectrometer. Mass-spectral ion peaks attributable to protonated molecules of intact, monooxygenated, and dioxygenated 2CEES (MH+, MOH+, and MO2H+, respectively) were observed. As ozone concentration was increased from zero to 30 ppm, the signal intensity of MH+ sharply decreased, that of MOH+ increased once and then decreased, and that of MO2H+ sharply increased until reaching a plateau. The signal intensity of MO2H+ at the plateau was 40 times higher than that of MH+ and 100 times higher than that of MOH+ in the case without in-line ozonation. Twenty-ppm ozone gas was adequate to give a linear calibration curve for 2CEES obtained by detecting the MO2H+ signal in the concentration range up to 60 μg/m3, which is high enough for hygiene management. In the low concentration range lower than 3 μg/m3, which is equal to the short-term exposure limit for HD, calibration plots unexpectedly fell off the linear calibration curve, but 0.6-μg/m3 vapor was actually detected with the signal-to-noise ratio of nine. Ozone was generated from instrumentation air by using a simple and inexpensive home-made generator. 2CEES was ozonated in 1-m extended sampling tube in only 1 s.

Repeated episodes of ozone inhalation amplifies the effects of allergen sensitization and inhalation on airway immune and structural development in Rhesus monkeys.

PubMed

Schelegle, Edward S; Miller, Lisa A; Gershwin, Laurel J; Fanucchi, Michelle V; Van Winkle, Laura S; Gerriets, Joan E; Walby, William F; Mitchell, Valerie; Tarkington, Brian K; Wong, Viviana J; Baker, Gregory L; Pantle, Lorraine M; Joad, Jesse P; Pinkerton, Kent E; Wu, Reen; Evans, Michael J; Hyde, Dallas M; Plopper, Charles G

2003-08-15

Twenty-four infant rhesus monkeys (30 days old) were exposed to 11 episodes of filtered air (FA), house dust mite allergen aerosol (HDMA), ozone (O3), or HDMA + O3 (5 days each followed by 9 days of FA). Ozone was delivered for 8 h/day at 0.5 ppm. Twelve of the monkeys were sensitized to house dust mite allergen (Dermatophagoides farinae) at ages 14 and 28 days by subcutaneous inoculation (SQ) of HDMA in alum and intraperitoneal injection of heat-killed Bordetella pertussis cells. Sensitized monkeys were exposed to HDMA aerosol for 2 h/day on days 3-5 of either FA (n = 6) or O3 (n = 6) exposure. Nonsensitized monkeys were exposed to either FA (n = 6) or O3 (n = 6). During the exposure regimen, parameters of allergy (i.e., serum IgE, histamine, and eosinophilia), airways resistance, reactivity, and structural remodeling were evaluated. Eleven repeated 5-day cycles of inhaling 0.5 ppm ozone over a 6-month period had only mild effects on the airways of nonsensitized infant rhesus monkeys. Similarly, the repeated inhalation of HDMA by HDMA-sensitized infant monkeys resulted in only mild airway effects, with the exception of a marked increase in proximal airway and terminal bronchiole content of eosinophils. In contrast, the combined cyclic inhalation of ozone and HDMA by HDMA sensitized infants monkeys resulted in a marked increase in serum IgE, serum histamine, and airways eosinophilia. Furthermore, combined cyclic inhalation of ozone and HDMA resulted in even greater alterations in airway structure and content that were associated with a significant elevation in baseline airways resistance and reactivity. These results suggest that ozone can amplify the allergic and structural remodeling effects of HDMA sensitization and inhalation.

The effectiveness of ozone and acidulant treatments in extending the refrigerated shelf life of fresh-cut potatoes.

PubMed

Calder, Beth L; Skonberg, Denise I; Davis-Dentici, Katherine; Hughes, Brianna H; Bolton, Jason C

2011-10-01

The objective of the study was to determine the effectiveness of acidulant dip treatments (with or without aqueous ozone) to reduce enzymatic browning and to extend the shelf life of fresh-cut potato slices during refrigerated storage (4 °C) for 28 d. Potato slices subjected to aqueous ozone (2 ppm) had significantly (P≤ 0.05) higher L-values and lower a-values, but ozone did not appear to have any effect on aerobic plate counts (APCs) or polyphenol oxidase (PPO) activity. NatureSeal (NS) and sodium acid sulfate (SAS) were the most effective acidulant treatments in reducing browning (significantly [P≤ 0.05] higher L-values, lower a-values, and browning index values) regardless of ozone treatment. NS and SAS also had lower PPO activity compared to other treatments on days 0 and 28, and significantly (P≤ 0.05) lower APCs (≤2.00 log CFU/g) over refrigerated storage. Therefore, the SAS treatment was comparable to NS, a commercially available product, and showed promise as an effective antibrowning dip to reduce browning and spoilage in fresh-cut potato products. Practical Application:  A 1% SAS dip treatment which included 1% citric and 1% ascorbic acid was found to be an effective antibrowning dip for fresh-cut potatoes along with NatureSeal®'s PS-10, compared to other treatments. They were both effective in maintaining low microbial counts over refrigerated storage. Additionally, aqueous ozone washes (2 ppm) showed significant benefits to reduce browning; however, ozone did not affect microbial counts or PPO enzyme activity. Therefore, the SAS treatment could have potential use in the fruit and vegetable industry to reduce browning and spoilage in fresh-cut potato products. © 2011 Institute of Food Technologists®

Ozone reaction characteristics of indoor floor dust examined in the emission cell "FLEC".

PubMed

Vibenholt, Anni; Clausen, Per Axel; Wolkoff, Peder

2014-07-01

Ozone reacts with C-C double bonds in common indoor VOCs and SVOCs contained in indoor dust and may be catalytically degraded on dust surfaces. The reaction between floor dust and ozone was investigated in the FLEC emission cell at different ozone concentrations and relative humidities (0%, 25%, and 50% RH). One gram of dust was spread on a clean stainless steel plate which was placed in the FLEC. Steady state reaction rate (kDust) at 2.2 ppm ozone was determined for four different floor dust samples collected in Danish homes and offices. This high concentration was necessary in order to measure and determine the consumption in the outlet air from the FLEC. Measurements were corrected for FLEC wall effects by subtraction of the steady state reaction rate between ozone and a FLEC on a stainless steel plate without dust (kFLEC). The composition of organic compounds in the dust was analyzed by pressurized liquid extraction and thermal desorption GC-MS before and after ozone exposure. kFLEC was independent of the ozone concentration and the reaction was treated as first order. The same was indicated for kDust since it remained unchanged at 2.2 and 1.6 ppm ozone for one dust sample. However, the measured kDust in the FLEC should be considered an average rate constant due to the FLEC geometry. kDust was in the range 0.039-0.14s(-1) pr. g dust at 50% RH. kDust was 3 times higher at 25% RH than at 50% RH and 6 times higher than at 0% RH. The inhomogeneity of the dust was assessed by experiments in triplicate with a new portion of dust each time. The relative standard deviation of kDust at 50% RH was 6-20%. The major identified compounds before and after ozone exposure included aldehydes, saturated and unsaturated linear alkanoic acids, benzoic acid and their methyl esters, dimethyl esters, phthalates and traces of α-pinene and limonene. Substantial increase of C7-C9 aldehydes was observed after ozone exposure. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of air, ozone, and nitrogen dioxide exposure on the oxidation of corn and soybean lipids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brooks, R.I.; Csallany, A.S.

1978-01-01

Whole, halves and ground samples of soybean seeds and whole corn kernels were exposed to air, 15 ppm NO2, or 1.5 ppm O3 continuously for 100 h at room temperature. Lipid oxidation was measured by polyunsaturated fatty acid (PUFA) and tocopherol destruction and formation of fluorescent lipofuscin-like pigments. Exposure of whole soybean and corn seeds to air, 15 ppm NO2, or 1.5 ppm O3 was found to induce no PUFA and tocopherol destruction and no formation of lipofuscin-like pigments. Tocopherol and PUFA destruction and lipofuscin-like pigment formation were detected in samples of soybean seed halves exposed to 15 ppm NO2more » or 1.5 ppm O3; however, only tocopherol destruction occurred in soybean halves exposed to air. Ground soybean samples exposed to air, 15 ppm NO2, or 1.5 ppm O3 incurred the greatest PUFA and tocopherol destruction and lipofuscin-like pigment formation. 25 references, 3 figures, 4 tables.« less

Role of neutrophilic inflammation in ozone-induced epithelial alterations in the nasal airways of rats

NASA Astrophysics Data System (ADS)

Cho, Hye Youn

Ozone is a principal oxidant air pollutant in photochemical smog. Epithelial cells lining the centriacinar region of lung and the proximal aspects of nasal passage are primary target sites for ozone-induced injury in laboratory animals. Acute exposure of rats to high ambient concentrations of ozone (e.g., 0.5 ppm) results in neutrophilic inflammation, epithelial hyperplasia and mucous cell metaplasia (MCM) in the nasal transitional epithelium (NTE) lining the proximal nasal airways. The principal purpose of the present study was to investigate the role of pre-metaplastic cellular responses, especially neutrophilic inflammation, in the pathogenesis of ozone-induced MCM in rat NTE. For this purpose, three specific hypotheses-based whole-animal inhalation studies were conducted. Male F344/N rats were exposed in whole-body inhalation chambers to 0 (filtered air) or 0.5 ppm ozone for 1-3 days (8 h/day). Histochemical, immunochemical, molecular and morphometric techniques were used to investigate the ozone-induced cellular and molecular events in the NTE. Two in vitro studies were also conducted to examine the effects of ozone-inducible cytokines (i.e., tumor necrosis factor-alpha; TNF- a, and interleukin-6; IL-6) on mucin gene (rMuc-5AC) expression. Ozone induced a rapid increase of rMuc-5AC mRNA in nasal tissues within hours after the start of exposure. It preceded the appearance of MCM, and persisted with MCM. Ozone-induced neutrophilic inflammation accompanied the mucin gene upregulation, but was resolved when MCM first appeared in the NTE. Antibody-mediated depletion of circulating neutrophils attenuated ozone-induced MCM, although it did not affect the ozone-induced epithelial hyperplasia and mucin mRNA upregulation. In another study, it was found that preexisting neutrophilic rhinitis induced by endotoxin augmented the ozone-induced MCM. However, pre-existing rhinitis did not alter the severity of ozone-induced epithelial hyperplasia and mucin gene upregulation. Ozone also induced rapid increases in TNF-a and IL-6 mRNAs in nasal tissues. In addition, exogenous TNF-α and IL- 6 induced increases in mucin mRNA in nasal tissues in vitro. In conclusion, though ozone alone is sufficient to induce epithelial proliferation and mucin gene upregulation which are early NTE cell events prior to the development of MCM, neutrophilic inflammation is essential for full phenotypic expression of MCM. TNF-α and IL-6 may be putative mediators of the ozone-induced upregulation of mucin mRNA in the NTE.

The effects of tropospheric ozone on the species dynamics of calcareous grassland.

PubMed

Thwaites, R H; Ashmore, M R; Morton, A J; Pakeman, R J

2006-11-01

Although ozone has been shown to reduce the growth of individual species and to alter the composition of simple species mixtures, there is little understanding of its long-term effects on species dynamics and composition in real communities. Intact turfs of calcareous grassland were exposed to four different ozone regimes in open-top chambers over three consecutive summers. Treatments provided a mean seasonal AOT40 ranging from approximately zero to 15 ppm h. Cumulative ozone exposure was a significant factor in compositional change, but only explained 4.6% of the variation. The dominant grass species (Festuca rubra) showed a consistent decline in cover in the high ozone treatment over time and the forb Campanula rotundifolia was lost from all three ozone treatments. The frequency of some species (Galium verum and Plantago lanceolata) increased with ozone exposure. Long-term effects of ozone on species composition in chalk grassland may be a function of both the sensitivity of individual species and the response of the dominant species.

Respiratory responses of vigorously exercising children to 0. 12 ppm ozone exposure

DOE Office of Scientific and Technical Information (OSTI.GOV)

McDonnell, W.F. 3d.; Chapman, R.S.; Leigh, M.W.

1985-10-01

Changes in respiratory function have been suggested for children exposed to less than 0.12 ppm ozone (O3) while engaged in normal activities. Because the results of these studies have been confounded by other variables, such as temperature or the presence of other pollutants or have been questioned as to the adequacy of exposure measurements, the authors determined the acute response of children exposed to 0.12 ppm O3 in a controlled chamber environment. Twenty-three white males 8 to 11 yr of age were exposed once to clean air and once to 0.12 ppm O3 in random order. Exposures were for 2.5more » h and included 2 h of intermittent heavy exercise. Measures of forced expiratory volume in one second (FEV1) and the symptom cough were determined prior to and after each exposure. A significant decline in FEV1 was found after the O3 exposure compared to the air exposure, and it appeared to persist for 16 to 20 h. No significant increase in cough was found due to O3 exposure. Forced vital capacity, specific airways resistance, respiratory frequency, tidal volume, and other symptoms were measured in a secondary exploratory analysis of this study.« less

Shelf Life Determination of Fresh Blueberries (Vaccinium corymbosum) Stored under Controlled Atmosphere and Ozone

PubMed Central

Eifert, Joseph D.; Williams, Robert C.; Marcy, Joseph E.; Welbaum, Gregory E.

2015-01-01

Fresh blueberries are commonly stored and transported by refrigeration in controlled atmospheres to protect shelf life for long periods of storage. Ozone is an antimicrobial gas that can extend shelf life and protect fruit from microbial contamination. Shelf life of fresh highbush blueberries was determined over 10-day storage in isolated cabinets at 4°C or 12°C under different atmosphere conditions, including air (control); 5% O2 : 15% CO2 : 80% N2 (controlled atmosphere storage (CAS)); and ozone gas (O3) 4 ppm at 4°C or 2.5 ppm at 12°C, at high relative humidity (90–95%). Samples were evaluated for yeast and molds growth, weight loss, and firmness. CAS and O3 did not delay or inhibit yeast and molds growth in blueberries after 10 days at both temperatures. Fruit stored at 4°C showed lower weight loss values compared with 12°C. Blueberries stored under O3 atmosphere showed reduced weight loss at 12°C by day 10 and loss of firmness when compared to the other treatments. Low concentrations of ozone gas together with proper refrigeration temperature can help protect fresh blueberries quality during storage. PMID:26904657

Shelf Life Determination of Fresh Blueberries (Vaccinium corymbosum) Stored under Controlled Atmosphere and Ozone.

PubMed

Concha-Meyer, Anibal; Eifert, Joseph D; Williams, Robert C; Marcy, Joseph E; Welbaum, Gregory E

2015-01-01

Fresh blueberries are commonly stored and transported by refrigeration in controlled atmospheres to protect shelf life for long periods of storage. Ozone is an antimicrobial gas that can extend shelf life and protect fruit from microbial contamination. Shelf life of fresh highbush blueberries was determined over 10-day storage in isolated cabinets at 4°C or 12°C under different atmosphere conditions, including air (control); 5% O2 : 15% CO2 : 80% N2 (controlled atmosphere storage (CAS)); and ozone gas (O3) 4 ppm at 4°C or 2.5 ppm at 12°C, at high relative humidity (90-95%). Samples were evaluated for yeast and molds growth, weight loss, and firmness. CAS and O3 did not delay or inhibit yeast and molds growth in blueberries after 10 days at both temperatures. Fruit stored at 4°C showed lower weight loss values compared with 12°C. Blueberries stored under O3 atmosphere showed reduced weight loss at 12°C by day 10 and loss of firmness when compared to the other treatments. Low concentrations of ozone gas together with proper refrigeration temperature can help protect fresh blueberries quality during storage.

Gas and Particle Oxidation Products from Ozone Aging of Airborne Diesel Particles

NASA Astrophysics Data System (ADS)

Holmen, B. A.; Chen, Z.

2005-12-01

Diesel exhaust emissions contain fine particulate matter (PM2.5) composed of carbon-based particles with adsorbed compounds, including water soluble and insoluble substances. Many nonpolar organic compounds associated with diesel particulate matter (DPM) are known to be mutagenic and carcinogenic. In the presence of ozone, these DPM compounds can be transformed into polar species that are more toxic and poorly characterized. Understanding the gas and particle reaction products from DPM aging in the presence of tropospheric ozone is important for air quality, climate change and aerosol health effects. Aging experiments were conducted in a flow reactor to identify gas and particle-phase reaction products of DPM exposed to ambient levels of ozone. Diesel bus exhaust particles were collected on filters and then exposed to 0.1 - 0.5 ppm O3 for 0 to 72 h. Gaseous polar organic products formed during the aging experiments were collected on Tenax TA adsorbent coated with PFBHA derivatization agent. A thermal desorption gas chromatography mass spectrometry (TD/GC/MS) method was developed to determine gas-phase and particle-phase organic compounds. PFBHA and BSTFA derivatization agents converted polar species into less polar analogues prior to analysis. Preliminary results indicate that DPM hydrocarbons react with O3 to form many gas-phase polar products containing C=O (carbonyl) and COOH (carboxy) functional groups. Particle-phase PAH and alkane concentrations decreased significantly depending on time of exposure.

Ozone, nitric acid, and ammonia air pollution is unhealthy for people and ecosystems in southern Sierra Nevada, California.

PubMed

Cisneros, Ricardo; Bytnerowicz, Andrzej; Schweizer, Donald; Zhong, Sharon; Traina, Samuel; Bennett, Deborah H

2010-10-01

Two-week average concentrations of ozone (O3), nitric acid vapor (HNO3) and ammonia (NH3) were measured with passive samplers during the 2002 summer season across the central Sierra Nevada Mountains, California, along the San Joaquin River drainage. Elevated concentrations of the pollutants were determined with seasonal means for individual sites ranging between 62 and 88 ppb for O3, 1.0-3.8 microg m(-3) for HNO3, and 2.6-5.2 microg m(-3) for NH3. Calculated O3 exposure indices were very high, reaching SUM00-191 ppm h, SUM60-151 ppm h, and W126-124 ppm h. Calculated nitrogen (N) dry deposition ranged from 1.4 to 15 kg N ha(-1) for maximum values, and 0.4-8 kg N ha(-1) for minimum values; potentially exceeding Critical Loads (CL) for nutritional N. The U.S., California, and European 8 h O3 human health standards were exceeded during 104, 108, and 114 days respectively, indicating high risk to humans from ambient O3.

The effect of increased ozone concentrations in the air on selected aspects of rat reproduction.

PubMed

Jedlińska-Krakowska, M; Gizejewski, Z; Dietrich, G J; Jakubowski, K; Glogowski, J; Penkowski, A

2006-01-01

Five-month-old male rates were exposed to 0.5 ppm ozone for 50 days, 5 hours a day. A week before the completion of ozone exposure, a biological test was performed to determine the fertilization rate and the survival rate of newborns in both ozone-exposed and control animals. After 50 days, the rats were sacrificed with an overdose of halotane, and testes were collected to assess the morphology and motility of spermatozoa. Neither the morphology of spermatozoa nor motility parameters determined by the CASA (computer-assisted sperm analysis) system showed statistically significant differences between ozone-exposed and control males. The number of successful matings and the survival rate of newborns per litter within one year postpartum were also similar in both groups. However, sperm concentration was by 17% lower in ozone-exposed rats, compared with the control animals.

Numerical simulation of ozone loss in the Antarctic winters 2005-2008: Comparison with MLS measurements

NASA Astrophysics Data System (ADS)

Kuttippurath, J.; Godin-Beekmann, S.; Lefevre, F.; Pazmino, A.

2009-04-01

The ozone loss in the recent Antarctic winters were high enough to pause a lag in the recovery phase of stratospheric ozone above this continent. We quantitatively examine the extent of ozone loss variability during 2005-2008 with simulations from a high resolution chemical transport model, MIMOSA-CHIM. The simulated results are cross-checked with the observed loss from Microwave Limb Sounder (MLS) satellite sensor data. This study uses the vortex averaged data at the potential temperature level 475 K from both MIMOSA and MLS to estimate the ozone loss by transport method. Minimum temperatures calculated from ECMWF analyzes over 50-90°S at 475 K are coldest in 2008 during June-July and in 2006 during September-November. In general, Antarctic winters experience NAT temperatures from mid-May to mid-October and ICE temperatures from June to September. Due to the saturation of chemical ozone loss, the year-to-year difference in temperatures do not have a large effect. The estimated cumulative ozone loss from MIMOSA-CHIM at 475 K is 3.2 in 2005, 2.9 in 2006, 2.8 in 2007 and 2.0 ppm in 2008. The measured cumulative loss in the respective years also show similar values: respectively 3.3, 3.2, 2.8 and 2.2 ppm in 2005, 2006, 2007 and 2008. Both data sets show the same loss trend, as the cumulative loss is highest in 2005 followed by 2006 and the lowest in 2008, and are in accord with the chlorine activation and denitrification found in the respective winters. The simulations in 2008 lack adequate diabatic descent as assessed from tracer simulations in comparison with measurements. This eventually produced relatively lower values for ozone loss in 2008 in both data sets even though the observed chlorine activation was found to be similar to previous winters.

Measurements of Criteria Pollutants in Suburban Locations in the Mexico City Metropolitan Area

NASA Astrophysics Data System (ADS)

Fentanes, O.; Sanchez, A.; Garcia, A.; Martinez, A.

2004-12-01

In the town of Santa Ana in the southern part of the Mexico City Metropolitan Area (MCMA) at an approximate height of 370 meters above the Valley of Mexico, a series of criteria pollutants (nitrogen dioxide, ozone, sulfur dioxide, and carbon monoxide) and meteorological parameters (wind speed and direction, temperature and relative humidity) were measured during the MCMA-2003 field campaign during April 2003. Santa Ana is considered a border site, agriculture being the predominant activity. The generated data in Santa Ana was compared with those from two representative atmospheric monitoring stations from the southeast zone (CENICA Supersite) and southwest (Revolucion Station) of Mexico City. The carbon monoxide and ozone concentrations measured in Santa Ana are atypical for a rural area. The sulfur dioxide and nitrogen dioxide concentrations are characteristic of the local activity. The average obtained during the measurement time for carbon monoxide was 0.86 ppm, the presence of the contaminant was within a 0.3 to 1.5 ppm range, 5 to 95 percentile, and does not follow the observed behavior of the monitoring stations that are located inside the urban area, although during the night (10 pm to 6 am) the carbon monoxide in Santa Ana was preset in levels from 0.4 to 1.5 ppm, 5 to 95 percentiles, average 0.92 ppm, above the reported concentrations at Revolucion Station, levels from 0.1 to 1.7 ppm, 5 to 95 percentiles; average 0.72 ppm. The presence of this contaminant can be attributed to transportation and accumulation phenomena. The ozone daytime behavior is similar to the one observed in the CENICA and Revolucion stations, but with a lower magnitude, the daily maximum generally occuring 2 or 3 hours after the urban stations. The one-hour average maximum values were 133 ppb in Santa Ana area and 188 ppb in the city. During the night the average concentrations were 37 ppb in Santa Ana and 17 ppb in the urban area. Nevertheless, the ozone average value in Santa Ana during the study was 49 ppb, slightly higher than the one obtained in the urban area, which was 44 ppb. The presence of this contaminant can be possibly attributed to the transportation and accumulation factors as well as to the low reactivity due to the absence of NOx, as explained in Dommen Josef and Prévôt, S.H. André, 2002, Characterization of the photooxidant formation in the metropolitan area of Milan from aircraft measurements, Journal of Geophysical Research, 107 (D22): 8197, doi: 10.1029/2000JD000283.

75 FR 47746 - Determination of Nonattainment and Reclassification of the Dallas/Fort Worth 1997 8-hour Ozone...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-09

...). Under section 181(a)(5) of the Act, and 40 CFR 51.907, an area can qualify for up to 2 one-year... ppm or less (40 CFR 51.907), the area is eligible for the first one-year extension to the attainment... highest average of the area's monitors was 0.091 ppm. 40 CFR 51.907(a), (c). Therefore, the DFW area does...

Investigation of gaseous ozone for MRSA decontamination of hospital side-rooms.

PubMed

Berrington, A W; Pedler, S J

1998-09-01

A domestic, gaseous ozone generator was investigated for use in the decontamination of hospital side-rooms that have housed patients colonized with methicillin-resistant Staphylococcus aureus (MRSA). Three models of bacterial contamination were used. These were exposed to ozone generation in a standard hospital side-room for 4 and 7 h. A methicillin-sensitive and a methicillin-resistant strain of S. aureus were compared. Ozone concentrations of 0.14 ppm were reached, levels which are sufficient to cause mild pulmonary toxicity. Bacterial counts were reduced in the vicinity of the gas generator in most instances, but the effect elsewhere in the room was, at best, limited. MRSA appeared more resistant to the effects of ozone than methicillin-sensitive S. aureus. We conclude that the device tested would be inadequate for the decontamination of such hospital side-rooms.

Pulmonary effects of ozone and nitrogen dioxide alone and combined in healthy and asthmatic adolescent subjects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koenig, J.Q.; Covert, D.S.; Smith, M.S.

Separate exposures to 0.12 ppm ozone (O3) or 0.18 ppm nitrogen dioxide (NO2) have not demonstrated consistent changes in pulmonary function in adolescent subjects. However, in polluted urban air, O3 and NO2 occur in combination. Therefore, this project was designed to investigate the pulmonary effects of combined O3 and NO2 exposures during intermittent exercise in adolescent subjects. Twelve healthy and twelve well-characterized asthmatic adolescent subjects were exposed randomly to clean air or 0.12 ppm O3 and 0.30 ppm NO2 alone or in combination during 60 minutes of intermittent moderate exercise (32.5 1/min). The inhalation exposures were carried out while themore » subjects breathed on a rubber mouthpiece with nose clips in place. The following pulmonary functional values were measured before and after exposure: peak flow, total respiratory resistance, maximal flow at 50 and 75 percent of expired vital capacity, forced expiratory volume in one second and forced vital capacity (FVC). Statistical significance of pulmonary function changes was tested by analysis of covariance for repeated measures. After exposure to 0.12 ppm O3 a significant decrease was seen in maximal flow at 50% of FVC in asthmatic subjects. After exposure to 0.30 ppm NO2 a significant decrease was seen in FVC also in the asthmatic subjects. One possible explanation for these changes is the multiple comparison effect. No significant changes in any parameters were seen in the asthmatic subjects after the combined O3-NO2 exposure or in the healthy subjects after any of the exposures.« less

Enhanced Raman Monitor Project

NASA Technical Reports Server (NTRS)

Westenskow, Dwayne

1996-01-01

Monitoring of gaseous contaminants stems from the need to ensure a healthy and safe environment. NASA/Ames needs sensors that are able to monitor common atmospheric gas concentrations as well as trace amounts of contaminant gases. To provide an accurate assessment of air quality, a monitoring system would need to be continuous and on-line with full spectrum capabilities, allowing simultaneous detection of all gas components in a sample, including both combustible and non-combustible gases. The system demands a high degree of sensitivity to detect low gas concentrations in the low-ppm and sub-ppm regions. For clean and healthy air ('good' category), criteria established by the EPA requires that contaminant concentrations not exceed 4 ppm of carbon monoxide (CO) in an 8 hour period, 60 ppb of ozone(O3) in a one hour period and 30 ppb of sulfur dioxide (SO2) in a 24 hour period. One step below this is the National Ambient Air Quality Standard ('moderate' category) which requires that contaminant concentrations not exceed 9 ppm of carbon monoxide (CO), 120 ppb of ozone (O3) and 140 ppb of sulfur dioxide (SO2) for their respective time periods. Ideally a monitor should be able to detect the concentrations specified in the 'good' category. To benchmark current abilities of Raman technology in gas phase analysis, laboratory experiments were performed to evaluate the RASCAL II anesthetic gas monitor.

Evaluation of soil pH and moisture content on in-situ ozonation of pyrene in soils.

PubMed

Luster-Teasley, S; Ubaka-Blackmoore, N; Masten, S J

2009-08-15

In this study, pyrene spiked soil (300 ppm) was ozonated at pH levels of 2, 6, and 8 and three moisture contents. It was found that soil pH and moisture content impacted the effectiveness of PAH oxidation in unsaturated soils. In air-dried soils, as pH increased, removal increased, such that pyrene removal efficiencies at pH 6 and pH 8 reached 95-97% at a dose of 2.22 mg O(3)/mg pyrene. Ozonation at 16.2+/-0.45 mg O(3)/ppm pyrene in soil resulted in 81-98% removal of pyrene at all pH levels tested. Saturated soils were tested at dry, 5% or 10% moisture conditions. The removal of pyrene was slower in moisturized soils, with the efficiency decreasing as the moisture content increased. Increasing the pH of the soil having a moisture content of 5% resulted in improved pyrene removals. On the contrary, in the soil having a moisture content of 10%, as the pH increased, pyrene removal decreased. Contaminated PAH soils were stored for 6 months to compare the efficiency of PAH removal in freshly contaminated soil and aged soils. PAH adsorption to soil was found to increase with longer exposure times; thus requiring much higher doses of ozone to effectively oxidize pyrene.

Abatement of tropospheric ozone: effects of strategies to improve air quality on public health and other sectors.

PubMed

Guest, C S; Morgan, P; Moss, J R; Woodward, A J; McMichael, A J

1996-06-01

The National Health and Medical Research Council's air quality goal for ozone in the troposphere (near the earth's surface) is 0.12 parts per million (ppm), averaged over one hour, similar to the United States standard, but less stringent than the guideline for Europe. We aimed to identify the environmental, economic and social changes that would be associated with changing the goal. Methods included literature review, economic assessments and group interviews. The group to benefit from lower exposures may include outdoor workers, school children and people not in regular day-time work indoors, because ozone is most prevalent during the daylight hours of the warmer months. A lower level could improve the yield of some crops. The causes and effects of tropospheric ozone are not appreciated except among groups with relevant commercial, industrial or scientific experience. However, the consultations identified frustration about the social problems caused by dependence on private motor vehicles. Short-term costs of compliance with a more stringent goal would fall principally on the users of transport. The value of the benefits was enough for many to support making the ozone goal more stringent, but those who required a demonstration of financial benefit (even including savings of health care costs) did not support any change to the goal. Based primarily on averted detriment to health, we recommend the more stringent level of 0.08 ppm (one-hour average) as the goal for the year 2005 in Australia and elsewhere. The addition of a goal with longer averaging time is also proposed.

Comparative Effects of Gamma Irradiation and Ozone Treatment on Hygienic Quality of Korean Red Ginseng Powder

NASA Astrophysics Data System (ADS)

Byun, Myung-Woo; Yook, Hong-Sun; Kang, Il-Jun; Chung, Cha-Kwon; Kwon, Joong-Ho; Choi, Kang-Ju

1998-06-01

For the purpose of improving hygienic quality of Korean red ginseng powder, the comparative effects of gamma irradiation and ozone treatment on the microbial and physicochemical properties were investigated. Gamma irradiation at 7.5 kGy resulted in sterilization of total aerobic bacteria, molds and coliforms below detective levels, while ozone treatment for 8 hours up to 18 ppm did not sufficiently eliminate the microorganisms of the red ginseng powder. Physicochemical properties including compositions of the red ginseng saponin (ginsenosides) and fatty acids, pH and hydrogen doanting activity were not significantly changed by gamma irradiation, whereas, ozone treatment caused significant changes in fatty acid compositions, TBA value, pH, acidity and hydrogen donating activity. The results from this study led us to conclude that gamma irradiation was more effective than ozone treatment both for the improvement of hygienic quality and for the maintenance of physicochemical quality of red ginseng powder.

Climate Response to the Increase in Tropospheric Ozone since Preindustrial Times: A Comparison between Ozone and Equivalent CO2 Forcings

NASA Technical Reports Server (NTRS)

Mickley L. J.; Jacob, D. J.; Field, B. D.; Rind, D.

2004-01-01

We examine the characteristics of the climate response to anthropogenic changes in tropospheric ozone. Using a general circulation model, we have carried out a pair of equilibrium climate simulations with realistic present-day and preindustrial ozone distributions. We find that the instantaneous radiative forcing of 0.49 W m(sup -2) due to the increase in tropospheric ozone since preindustrial times results in an increase in global mean surface temperature of 0.28 C. The increase is nearly 0.4 C in the Northern Hemisphere and about 0.2 C in the Southern Hemisphere. The largest increases (greater than 0.8 C) are downwind of Europe and Asia and over the North American interior in summer. In the lower stratosphere, global mean temperatures decrease by about 0.2 C due to the diminished upward flux of radiation at 9.6 micrometers. The largest stratospheric cooling, up to 1.0 C, occurs over high northern latitudes in winter, with possibly important implications for the formation of polar stratospheric clouds. To identify the characteristics of climate forcing unique to tropospheric ozone, we have conducted two additional climate equilibrium simulations: one in which preindustrial tropospheric ozone concentrations were increased everywhere by 18 ppb, producing the same global radiative forcing as present-day ozone but without the heterogeneity; and one in which CO2 was decreased by 25 ppm relative to present day, with ozone at present-day values, to again produce the same global radiative forcing but with the spectral signature of CO2 rather than ozone. In the first simulation (uniform increase of ozone), the global mean surface temperature increases by 0.25 C, with an interhemispheric difference of only 0.03 C, as compared with nearly 0.2 C for the heterogeneous ozone increase. In the second simulation (equivalent CO2), the global mean surface temperature increases by 0.36 C, 30% higher than the increase from tropospheric ozone. The stronger surface warming from CO2 is in part because CO2 forcing (obscured by water vapor) is shifted relatively poleward where the positive ice-albedo feedback amplifies the climate response and in part because the magnitude of the CO2 forcing in the mid-troposphere is double that of ozone. However, we find that CO2 is far less effective than tropospheric ozone in driving lower stratospheric cooling at high northern latitudes in winter.

Improvements in a chemiluminescent ozone analyzer for respiratory applications

NASA Astrophysics Data System (ADS)

Ben-Jebria, Abdellaziz; Hu, Shu-Chieh; Ultman, James S.

1990-11-01

The performance characteristics of a previously developed analyzer utilizing the homogeneous chemiluminescent reaction of ozone (O3) with a stoichiometric excess of 2-methyl-2-butene were improved with the eventual goal of measuring the distribution of O3 in a single human breath. By increasing the sampling flow from 200 to 400 ml/min and utilizing a combination of analog and digital filtering, it was possible to improve the signal-to-noise ratio at 0.5 ppm O3 from 5.5 to 28, the minimum detection limit from 0.02 to 0.01 ppm, the sensitivity from 1.5 to 2.3 na/ppm, and the 10%-90% step-response time from 200 to 100 ms. Humidity, temperature, and inlet gas composition interferences were also evaluated. While temperature and humidity have no influence on the analyzer output, the substitution of carbon dioxide for oxygen increased the analyzer sensitivity by 3.8% for each percent of CO2 that was present. Thus, provided that an appropriate correction for carbon dioxide is made, these improvements allow the instrument to monitor inhaled and exhaled O3 concentrations with a rapid dynamic response and over a broad range of physiologically relevant values.

Regional and local meteorology influences high-resolution tropospheric ozone concentration in the Los Angeles Basin

NASA Astrophysics Data System (ADS)

Koutzoukis, S.; Jenerette, D.; Chandler, M.; Wang, J.; Ge, C.; Ripplinger, J.

2017-12-01

Urban air quality and climate directly affect resident health. The Los Angeles (LA) Basin is a highly populated metropolitan area, with widespread point sources of ozone (O3) precursors (NOx , Volatile Organic Compounds, CO) from fossil fuel combustion. The LA basin exists on a coast-to-mountain gradient, with increasing temperatures towards the Transverse Ranges, which rise to 1700m. Frequently not compliant with 8-hour O3 standards, the LA and South Coast Air Basins are designated as severe and extreme non-attainment areas. Summer weather in the LA basin is characterized by a persistent high pressure system, creating an inversion that traps air pollutants, including O3 precursors, coupled with physical geography that blocks prevailing upper atmosphere air flow. These interactions make neighborhood-level O3 levels more variable than common regional models. Over the summer of 2017, we investigated the importance of local meteorology, wind patterns and air temperature, in transporting and mixing ozone precursors from point sources along the coast-to-mountain gradient. We deployed a network of six EPA federal equivalent method ozone and meteorological sensors in three campaigns in the LA basin along the coast-to-mountain transect. Each campaign, we collaborated with citizen scientists to deploy three sensor stations in two, 4 km2 quadrats, for a total of six high-resolution 4 km2 pixels. O3 concentrations vary greatly along the transect. At the coastal sites, daily O3 ranges from 0ppm to 60ppm and the range increases at the inland sites, to 100ppm. At all sites, there was a positive relationship between wind speed, air temperature, and O3 concentration, with increasing correlation inland. The Pearson correlation coefficient between wind speed and O3 concentration doubles from the coast to inland, and triples between air temperature and O3. The site-specific relationships between O3 and wind direction and temperature vary, suggesting neighborhood-effects from local point sources.

Optimization in the formaldehyde determination at sub-ppm level from acetals by HPLC-DAD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Medvedovici, A.; David, V.; David, F.

1999-02-01

Carbonylic compounds are mainly monitored as atmospheric pollutants, due to their major contribution to the formation of free radicals and ozone, by means of photolysis. Determination of formaldehyde at sub-ppm level as impurity in acetals using HPLC-DAD is described. Automated on-line precolumn derivatization reaction with 2,4-dinitrophenylhydrazine has been used. Breakdown rates of some industrial scale used acetals (Methylal, Ethylal) to formaldehyde by hydrolysis in aqueous media, according to pH, are described.

Mechanisms of Stratospheric Ozone Transport.

DTIC Science & Technology

1982-12-03

amounts orcur too fat south and about 1 month too late. 92 CHANGE IN (740) (PPM) DIABATIC. cos ( LAT ) 70 50 ~40 (D 30_ _ _ _ _ ) 1 5 Ŗ 2.5 Z. 20 10 0 D...AD-A122 609 MECHANISMS OF STRATOSPHERIC OZONE BRANSPOR(U) NAVAL RESEARCH LAB WASHINGTON DC R B ROOD ET AL 03 DEC 82 UNCLASSIFIED F/G 4/ 1 ...NLIEIIIIEIIII EIIIIIIIIIIIIl IIIEIIIIIEEEEE IIIIIIIIIIIIIl EIIIIIIIIIIIIl EIIIIIIIIIIIIl 1111.0 112 M *0 MIt ROCLt RLS’OLU7ION TLST CHART - - - ,T 1 m -N ;’ V

Effects of cadmium concentration on ozone-induced phytotoxicity in cress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Czuba, M.; Ormrod, D.P.

1974-01-01

Cadmium solutions at concentrations of 0, 10, 40, 100, 500 or 1000 ppm were applied to the soil around cress (Lepidium sativum L. cv. Fine Curled) every 4th day for several weeks. Four week old plants were fumigated once at ozone levels of 0, 5, 10, 20, 25 or 30-35 pphm for 6 hours. Plants that had received higher concentrations of cadmium showed markedly increased sensitivity to ozone in terms of visible leaf damage after ozone treatment. Plants receiving cadmium solution alone or those receiving ozone treatment alone either did not show leaf damage or as much leaf damage asmore » plants which had received both treatments. Mineral analyses of plant tissues showed the relationship between tissue content of both essential and toxic cations and the sensitivity of the plant to various ozone levels. Pigment analyses showed changes in chlorophyll amounts and ratios between treatments. Statistical analyses of data for morphological parameters showed that there is an interaction between Cd and ozone treatments over a range of concentrations.« less

Ozone exposure thresholds and foliar injury on forest plants in Switzerland.

PubMed

VanderHeyden, D; Skelly, J; Innes, J; Hug, C; Zhang, J; Landolt, W; Bleuler, P

2001-01-01

Canton Ticino in southern Switzerland is exposed to some of the highest concentrations of tropospheric ozone in Europe. During recent field surveys in Canton Ticino, foliar symptoms identical to those caused by ozone have been documented on native tree and shrub species. In Europe, the critical ozone level for forest trees has been defined at an AOT40 of 10 ppm.h O3 (10 ppm.h accumulated exposure of ozone over a threshold of 40 ppb) during daylight hours over a six-month growing season. The objective of this study was to determine the amount of ambient ozone required to induce visible foliar symptoms on various forest plant species in southern Switzerland. Species were grown within eight open-top chambers and four open plots at the Vivaio Lattecaldo Cantonal Forest Nursery in Ticino, Switzerland. Species differed significantly in terms of the ppb.h exposures needed to cause visible symptoms. The most to least symptomatic species grown within open-plots in this study rank as Prunus serotina, Salix viminalis, Vibrnum lantana, Rhamnus cathartica, Betula pendula, Rumex obtusifolius, Sambucus racemosa, Morus nigra, Prunus avium, Fraxinus excelsior, Rhamnus frangula, Alnus viridis, Fagus sylvatica and Acer pseudoplatanus. Similar rankings were obtained in the non-filtered chamber plots. The ranking of species sensitivity closely follows AOT values for the occurrence of initial symptoms and symptom progression across the remainder of the exposure season. Species that first showed evidence of foliar injury also demonstrated the most sensitivity throughout the growing season, with symptoms rapidly advancing over ca. 25-30% of the total plant leaf surfaces by the end of the observation period. Conversely, those species that developed symptoms later in the season had far less total injury to plant foliage by the end of the observation period (1.5 to < 5% total leaf area injured). The current European ambient ozone standard may be insufficient to protect native plant species from visible foliar injury, and many more native species may be sensitive to ozone-induced foliar injury than are currently known.

Inactivation of H1N1 viruses exposed to acidic ozone water

NASA Astrophysics Data System (ADS)

Uhm, Han S.; Lee, Kwang H.; Seong, Baik L.

2009-10-01

The inactivation of H1N1 viruses upon exposure to acidic ozone water was investigated using chicken allantoic fluids of different dilutions, pH values, and initial ozone concentrations. The inactivation effect of the acidic ozone water was found to be stronger than the inactivation effect of the ozone water combined with the degree of acidity, indicating a synergic effect of acidity on ozone decay in water. It is also shown that acidic ozone water with a pH value of 4 or less is very effective means of virus inactivation if provided in conjunction with an ozone concentration of 20 mg/l or higher.

Survival of Listeria monocytogenes on fresh blueberries (Vaccinium corymbosum) stored under controlled atmosphere and ozone.

PubMed

Concha-Meyer, Anibal; Eifert, Joseph; Williams, Robert; Marcy, Joseph; Welbaum, Gregory

2014-05-01

Listeria monocytogenes is a foodborne pathogen that represents a high risk for consumers because it can grow under refrigeration conditions and can also develop acid tolerance. Fresh blueberries are hand-picked, packed, and transported under refrigeration without receiving a microbial inactivation treatment. The aim of this work was to study the survival of L. monocytogenes in fresh highbush blueberries stored at 4 or 12 °C under different controlled atmosphere conditions, including air (control); 5% O2, 15% CO2, 80% N2 (controlled atmosphere storage [CAS]); or ozone gas (O3), 4 ppm at 4 °C or 2.5 ppm at 12 °C, at high relative humidity (90 to 95%) for a total of 10 days. Fresh blueberries inside a plastic clamshell were spot inoculated with the bacteria and were stored at 4 or 12 °C in isolated cabinets under air, CAS, and O3 atmospheric conditions. Samples were evaluated on days 0, 1, 4, 7, and 10 for microbial growth using modified Oxford agar. CAS did not delay or inhibit L. monocytogenes growth in fresh blueberries after 10 days. O3 achieved 3- and 2-log reductions when compared with air treatment at 4 and 12 °C, respectively. Low concentrations of O3 together with proper refrigeration temperature can ensure product safety throughout transportation. O3 is a strong antimicrobial that safely decomposes to oxygen and water without leaving residues and can be used as an alternative method to prevent bacterial growth during a long transport period.

Effects of cadmium and zinc on ozone-induced phytotoxicity in cress and lettuce

DOE Office of Scientific and Technical Information (OSTI.GOV)

Czuba, M.; Ormrod, D.P.

1973-01-01

Cadmium or zinc solutions were applied to the foliage or roots of lettuce (Lactuca sativa L. cv. Grand Rapids) and cress (Lepidium sativum L. cv. Fine Curled) at concentrations of 100 parts per million (ppm) every four days for several weeks. Four weeks after sowing, plants were fumigated with 35 parts per hundred million (pphm) ozone, for 6 hours. Cress plants which had received root application of cadmium showed markedly increased ozone-induced phytotoxicity in terms of visible leaf damage and pigment degradation; in lettuce only pigment degradation was evident. There was less effect of zinc or foliar-applied cadmium on ozonemore » phytotoxicity.« less

Dose-response study of healthy, heavily exercising men exposed to ozone at concentrations near the ambient air quality standard

DOE Office of Scientific and Technical Information (OSTI.GOV)

Linn, W.S.; Avol, E.L.; Shamoo, D.A.

1986-07-01

Twenty-four healthy, well-conditioned young adult male volunteers, free of asthma or clinical respiratory allergies, were exposed to purified air containing ozone (O3) at 0.16, 0.14, 0.12, 0.10, 0.08, and 0.00 part per million (ppm). Exposures were separated by 2-week intervals, occurred in random order, and lasted 2 hours each. Temperature was 32 +/- 1/sup 0/C and relative humidity was 38 +/- 3%, simulating Los Angeles area smog conditions. Subjects exercised 15 minutes of each half hour, attaining ventilation rates averaging 68 L/min (approximately 35 L/min per m2 body surface area). Lung function was measured pre-exposure and after 1 hr andmore » 2 hr of exposure. Airway responsiveness to a cold-air challenge was measured immediately following the 2-hr exposure. Symptoms were recorded before, during, and for one-week periods following exposures. For the group as a whole, no meaningful untoward effects were found except for a mild typical respiratory irritant response after 2 hr exposure to 0.16 ppm O3. Two individual subjects showed possible responses at 0.14 ppm, and one of them also at 0.12 ppm. In comparison to some previous investigations, this study showed generally less response to O3. The comparative lack of response may relate to the favorable clinical status of the subjects, the pattern of exercise during exposure, or some other factor not yet identified.« less

Reduced exercise time in competitive simulations consequent to low level ozone exposure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schelegle, E.S.; Adams, W.C.

Ten highly trained endurance athletes were studied to determine the effects of exposure to low ozone (O/sub 3/) concentrations on simulated competitive endurance performance and associated physiological and subjective symptom responses. Each subject was randomly exposed to filtered air (FA), and to 0.12, 0.18, and 0.24 ppm O/sub 3/ while performing a 1 h competitive simulation protocol on a bicycle ergometer. Endurance performance was evaluated by the number of subjects unable to complete rides (last 30 min at an intense work load of approximately 86% VO/sub 2/max). All subjects completed the FA exposure, whereas one, five, and seven subjects didmore » not complete the 0.12, 0.18, and 0.24 ppm O/sub 3/ exposures, respectively. Statistical analysis indicated a significant (P less than 0.05) increase in the inability of subjects to complete the competitive simulations with increasing O/sub 3/ concentration, including a significant difference between the 0.24 ppm O/sub 3/ and FA exposure. Significant decreases (P less than 0.05) were also observed following the 0.18 and 0.24 ppm O/sub 3/ exposures, respectively, in forced vital capacity (-7.8 and -9.9%), and forced expiratory volume in 1 s (-5.8 and -10.5%). No significant O/sub 3/ effect was observed for exercise respiratory metabolism or ventilatory pattern responses. However, the number of reported subjective symptoms increased significantly following the 0.18 and 0.24 ppm O/sub 3/ protocols. These data demonstrate significant decrements in simulated competitive endurance performance and in pulmonary function, with accompanying enhanced subjective symptoms, following exposure to low O/sub 3/ levels commonly observed in numerous metropolitan environments during the summer months.« less

Evaluation of ozone emissions and exposures from consumer products and home appliances.

PubMed

Zhang, Q; Jenkins, P L

2017-03-01

Ground-level ozone can cause serious adverse health effects and environmental impacts. This study measured ozone emissions and impacts on indoor ozone levels and associated exposures from 17 consumer products and home appliances that could emit ozone either intentionally or as a by-product of their functions. Nine products were found to emit measurable ozone, one up to 6230 ppb at a distance of 5 cm (2 inches). One use of these products increased room ozone concentrations by levels up to 106 ppb (mean, from an ozone laundry system) and personal exposure concentrations of the user by 12-424 ppb (mean). Multiple cycles of use of one fruit and vegetable washer increased personal exposure concentrations by an average of 2550 ppb, over 28 times higher than the level of the 1-h California Ambient Air Quality Standard for ozone (0.09 ppm). Ozone emission rates ranged from 1.6 mg/h for a refrigerator air purifier to 15.4 mg/h for a fruit and vegetable washer. The use of some products was estimated to contribute up to 87% of total daily exposures to ozone. The results show that the use of some products may result in potential health impacts. © 2016 The Authors. Indoor Air published by John Wiley & Sons Ltd.

Effect of acute ozone exposure on the lung metabolomes of obese and lean mice.

PubMed

Mathews, Joel Andrew; Kasahara, David Itiro; Cho, Youngji; Bell, Lauren Nicole; Gunst, Philip Ross; Karoly, Edward D; Shore, Stephanie Ann

2017-01-01

Pulmonary responses to the air pollutant, ozone, are increased in obesity. Both obesity and ozone cause changes in systemic metabolism. Consequently, we examined the impact of ozone on the lung metabolomes of obese and lean mice. Lean wildtype and obese db/db mice were exposed to acute ozone (2 ppm for 3 h) or air. 24 hours later, the lungs were excised, flushed with PBS to remove blood and analyzed via liquid-chromatography or gas-chromatography coupled to mass spectrometry for metabolites. Both obesity and ozone caused changes in the lung metabolome. Of 321 compounds identified, 101 were significantly impacted by obesity in air-exposed mice. These included biochemicals related to carbohydrate and lipid metabolism, which were each increased in lungs of obese versus lean mice. These metabolite changes may be of functional importance given the signaling capacity of these moieties. Ozone differentially affected the lung metabolome in obese versus lean mice. For example, almost all phosphocholine-containing lysolipids were significantly reduced in lean mice, but this effect was attenuated in obese mice. Glutathione metabolism was also differentially affected by ozone in obese and lean mice. Finally, the lung metabolome indicated a role for the microbiome in the effects of both obesity and ozone: all measured bacterial/mammalian co-metabolites were significantly affected by obesity and/or ozone. Thus, metabolic derangements in obesity appear to impact the response to ozone.

Acute Ozone-Induced Pulmonary and Systemic Metabolic ...

EPA Pesticide Factsheets

Acute ozone exposure increases circulating stress hormones and induces metabolic alterations in animals and humans. We hypothesized that the increase of adrenal-derived stress hormones is necessary for both ozone-induced metabolic effects and lung injury. Male Wistar-Kyoto rats underwent adrenal demedullation (DEMED), total bilateral adrenalectomy (ADREX), or sham surgery (SHAM). After a 4 day recovery, rats were exposed to air or ozone (1ppm), 4h/day for 1 or 2 days. Circulating adrenaline levels dropped to nearly zero in DEMED and ADREX rats relative to air-exposed SHAM. Corticosterone levels tended to be low in DEMED rats and dropped to nearly zero in ADREX rats. Adrenalectomy in air-exposed rats caused modest changes in metabolites and lung toxicity parameters. Ozone-induced hyperglycemia and glucose intolerance were markedly attenuated in DEMED rats with nearly complete reversal in ADREX rats. Ozone increased circulating epinephrine and corticosterone in SHAM but not in DEMED or ADREX rats. Free fatty acids (p=0.15) and branched-chain amino acids increased after ozone exposure in SHAM but not in DEMED or ADREX rats. Lung minute volume was not affected by surgery or ozone but ozone-induced labored breathing was less pronounced in ADREX rats. Ozone-induced increases in lung protein leakage and neutrophilic inflammation were markedly reduced in DEMED and ADREX rats (ADREX>DMED). Ozone-mediated decreases in circulating white blood cells in SHAM were not obser

Acute Ozone-Induced Pulmonary and Systemic Metabolic ...

EPA Pesticide Factsheets

Acute ozone exposure increases circulating stress hormones and induces peripheral metabolic alterations in animals and humans. We hypothesized that the increase of adrenal-derived stress hormones is necessary for ozone-induced systemic metabolic effects and lung injury. Male Wistar-Kyoto rats (12 week-old) underwent total bilateral adrenalectomy (ADREX), adrenal demedullation (DEMED) or sham surgery (SHEM). After 4 day recovery, rats were exposed to air or ozone (1ppm), 4h/day for 1 or 2 days. Circulating adrenaline levels dropped to nearly zero in DEMED and ADREX rats relative to air-exposed SHAM. Corticosterone levels tended to be low in DEMED rats and dropped to nearly zero in ADREX rats. Adrenalectomy in air-exposed rats caused modest changes in metabolites and lung toxicity parameters. Ozone-induced hyperglycemia and glucose intolerance were markedly attenuated in DEMED with nearly complete reversal in ADREX rats. Ozone increased circulating epinephrine and corticosterone in SHAM but not in DEMED or ADREX rats. Free fatty acids and branched-chain amino acids tended to increase after ozone exposure in SHAM but not in DEMED or ADREX rats. Lung minute volume was not affected by surgery or ozone but ozone-induced labored breathing was less pronounced in ADREX rats. Ozone-induced increases in lung protein leakage and neutrophilic inflammation were markedly reduced in DEMED and ADREX rats (ADREX>DMED). Ozone-mediated decrease in circulating WBC in SHAM was not

Analysis of the Sensing Properties of a Highly Stable and Reproducible Ozone Gas Sensor Based on Amorphous In-Ga-Zn-O Thin Film.

PubMed

Wu, Chiu-Hsien; Jiang, Guo-Jhen; Chang, Kai-Wei; Deng, Zu-Yin; Li, Yu-Ning; Chen, Kuen-Lin; Jeng, Chien-Chung

2018-01-09

In this study, the sensing properties of an amorphous indium gallium zinc oxide (a-IGZO) thin film at ozone concentrations from 500 to 5 ppm were investigated. The a-IGZO thin film showed very good reproducibility and stability over three test cycles. The ozone concentration of 60-70 ppb also showed a good response. The resistance change (Δ R ) and sensitivity ( S ) were linearly dependent on the ozone concentration. The response time ( T 90-res ), recovery time ( T 90-rec ), and time constant (τ) showed first-order exponential decay with increasing ozone concentration. The resistance-time curve shows that the maximum resistance change rate (dRg/dt) is proportional to the ozone concentration during the adsorption. The results also show that it is better to sense rapidly and stably at a low ozone concentration using a high light intensity. The ozone concentration can be derived from the resistance change, sensitivity, response time, time constant (τ), and first derivative function of resistance. However, the time of the first derivative function of resistance is shorter than other parameters. The results show that a-IGZO thin films and the first-order differentiation method are promising candidates for use as ozone sensors for practical applications.

Analysis of the Sensing Properties of a Highly Stable and Reproducible Ozone Gas Sensor Based on Amorphous In-Ga-Zn-O Thin Film

PubMed Central

Wu, Chiu-Hsien; Jiang, Guo-Jhen; Chang, Kai-Wei; Deng, Zu-Yin; Li, Yu-Ning; Chen, Kuen-Lin; Jeng, Chien-Chung

2018-01-01

In this study, the sensing properties of an amorphous indium gallium zinc oxide (a-IGZO) thin film at ozone concentrations from 500 to 5 ppm were investigated. The a-IGZO thin film showed very good reproducibility and stability over three test cycles. The ozone concentration of 60–70 ppb also showed a good response. The resistance change (ΔR) and sensitivity (S) were linearly dependent on the ozone concentration. The response time (T90-res), recovery time (T90-rec), and time constant (τ) showed first-order exponential decay with increasing ozone concentration. The resistance–time curve shows that the maximum resistance change rate (dRg/dt) is proportional to the ozone concentration during the adsorption. The results also show that it is better to sense rapidly and stably at a low ozone concentration using a high light intensity. The ozone concentration can be derived from the resistance change, sensitivity, response time, time constant (τ), and first derivative function of resistance. However, the time of the first derivative function of resistance is shorter than other parameters. The results show that a-IGZO thin films and the first-order differentiation method are promising candidates for use as ozone sensors for practical applications. PMID:29315218

Atopic asthmatic subjects but not atopic subjects without ...

EPA Pesticide Factsheets

BACKGROUND: Asthma is a known risk factor for acute ozone-associated respiratory disease. Ozone causes an immediate decrease in lung function and increased airway inflammation. The role of atopy and asthma in modulation of ozone-induced inflammation has not been determined. OBJECTIVE: We sought to determine whether atopic status modulates ozone response phenotypes in human subjects. METHODS: Fifty volunteers (25 healthy volunteers, 14 atopic nonasthmatic subjects, and 11 atopic asthmatic subjects not requiring maintenance therapy) underwent a 0.4-ppm ozone exposure protocol. Ozone response was determined based on changes in lung function and induced sputum composition, including airway inflammatory cell concentration, cell-surface markers, and cytokine and hyaluronic acid concentrations. RESULTS: All cohorts experienced similar decreases in lung function after ozone. Atopic and atopic asthmatic subjects had increased sputum neutrophil numbers and IL-8 levels after ozone exposure; values did not significantly change in healthy volunteers. After ozone exposure, atopic asthmatic subjects had significantly increased sputum IL-6 and IL-1beta levels and airway macrophage Toll-like receptor 4, Fc(epsilon)RI, and CD23 expression; values in healthy volunteers and atopic nonasthmatic subjects showed no significant change. Atopic asthmatic subjects had significantly decreased IL-10 levels at baseline compared with healthy volunteers; IL-10 levels did not significa

Effect of Substrate Character on Heterogeneous Ozone Reaction Rate with Individual PAHs and Their Reaction Mixtures

NASA Astrophysics Data System (ADS)

Holmen, B. A.; Stevens, T.

2009-12-01

Vehicle exhaust contains many unregulated chemical compounds that are harmful to human health and the natural environment, including polycyclic aromatic hydrocarbons (PAH), a class of organic compounds derived from fuel combustion that can be carcinogenic and mutagenic. PAHs have been quantified in vehicle-derived ultrafine particles (Dp<100nm), which are more toxic than larger particles and are linked to adverse health problems, including respiratory and cardiac disease. Once emitted into the atmosphere, particle-bound PAHs can undergo “aging” reactions with oxidants, such as ozone, to form more polar species. These polar reaction products include species such as quinones that can be more toxic than the parent PAH compounds. Here, 0.4ppm ozone was reacted over a 24-hour period with the 16 EPA priority PAHs plus coronene adsorbed to (i) a quartz fiber filter and (ii) NIST diesel PM. The difference in the PAH/O3 heterogeneous reaction rate resulting from the two substrates will be discussed. The experiments were completed by spiking a known PAH mixture to the solid, reacting the samples with gas-phase ozone, and determining both PAH loss over time and products formed, using thermal-desorption gas chromatography / mass spectrometry (TD-GC/MS). The individual PAHs anthracene, phenanthrene, and fluorene, adsorbed to a QFF were also separately reacted with 0.4 ppm ozone. A volatilization control and the collection of volatilized PAHs using a Tenax-packed thermal desorption vial completed the mass balance and aided determination parent-product relationships. Heterogeneous reaction products analyzed directly without derivatization indicate the formation of 9,10-anthracenedione, 9H-fluoren-9-one, and (1,1’-biphenyl)-2,2’-dicarboxaldehyde from the reaction of ozone with the PAH mix on a QFF, but only 9,10-anthracenedione was detected for the diesel PM reaction. The implications of these results for aging of diesel particulate in urban environments will be discussed.

Evaluation of a Recirculating Dipper Well Combined with Ozone Sanitizer for Control of Foodborne Pathogens in Food Service Operations.

PubMed

Almeida, Giselle; Gibson, Kristen E

2016-09-01

In the retail food service industry, small countertop sinks, or dipper wells, are utilized to rinse and store serving utensils between uses. These dipper wells are designed to operate under a constant flow of water, which serves both to prevent the accumulation of microorganisms and to aid in the cleanliness of the dipper well itself. Here, a recirculating dipper well ozone sanitation system (DWOSS) was evaluated for the control and inactivation of Escherichia coli , Listeria innocua , PRD1 bacteriophage, and Staphylococcus aureus present on a stainless steel disher. In a low ozone (O 3 ) demand medium, the DWOSS achieved over a 5-log reduction for E. coli , L. innocua , and PRD1 at 30 s when exposed to 0.45 to 0.55 ppm of residual O 3 . A greater than 5-log total CFU reduction was achieved for S. aureus at a 600-s exposure time and 0.50 ppm of residual O 3 . When evaluated in the presence of high O 3 demand medium (10% skim milk), the DWOSS performed significantly better (P < 0.05) for all microbe-exposure time combinations compared with a conventional dipper well with respect to the reduction of microbes on the stainless steel disher. For example, at 30 s, the DWOSS achieved 4.37, 2.48, 1.38, and 1.31 greater log (CFU or PFU) reduction of E. coli , L. innocua , PRD1, and S. aureus , respectively, than a conventional dipper well. In addition, the DWOSS was evaluated under two neglect scenarios to determine its ability to control microbes in 10% skim milk medium on the stainless steel disher and within the dipper well basin itself over an extended period of use (2 h of use per day over 5 days). Considering the efficacy of the DWOSS unit against the microbes evaluated here, the integration of ozone into a dipper well could be a potential critical control point to reduce the incidence of microbial contamination during retail food service. To our knowledge, a dipper well with a cleaning-in-place sanitizing system is not currently available for use in the food service industry; and, thus, this is the first study to evaluate the efficacy of a cleaning-in-place dipper well.

Health assessment for Louisiana Army Ammunition Plant, Shreveport, Webster County, Louisiana, Region 6. CERCLIS No. LA0213820533. Preliminary report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1989-04-10

The Louisiana Army Ammunition Plant (LAAP) is listed on the National Priorities List. The site is a 15,000-acre Federal facility located in Shreveport (Webster Parish), Louisiana. On-site ground water beneath 16 unlined surface impoundments near the southern boundary is contaminated. Access to LAAP is restricted and under 24-hour security. Contaminants include 2,4,6-trinitrotoluene (TNT), cyclonite (RDX), trinitrobenzene (TNB), and homocyclonite (HMX). Preliminary on-site sampling results have identified TNT (493,133 ppm in sediment/subsoil, 483,556 ppm in sludge, 1,033 ppm in surface soil, 7 ppm in surface water, and 18 ppm in ground water), RDX (60,224 ppm in sediment/subsoil, 602 ppm in surfacemore » soil, 60,224 ppm in sludge, and 14 ppm in ground water), TNB (2 ppm in surface water and 8 ppm in ground water), and HMX (4 ppm in ground water). Based on available information, the site is considered to be of potential public health concern because of the risk to human health caused by the possibility of human exposure to hazardous substances.« less

Remote detection of air pollution stress to vegetation - Laboratory-level studies

NASA Technical Reports Server (NTRS)

Westman, Walter E.; Price, Curtis V.

1987-01-01

An experimental investigation of the role of leaf chemistry, anatomy, moisture content, and canopy density on spectral reflectance in healthy and pollution stressed western conifer needles and broad-leafed species of California coastal sage scrub is presented. Acid mist at a level of pH 2.0 is found to more severely effect chlorophyll loss and leaf death than ozone at a level of 0.2 ppm for a four-week period. Both pollutants cause water loss, affecting Bands 4 and 5 in nonlinear ways. The infrared bands initially rise as free water is lost, and subsequently, scattering and reflectance decline. The net effect is shown to be a reduction in TM 4/3 and a rise in TM 5/4 with pollution stress. Under more severe pollution stresses, the decline of leaf area indices due to accelerated leaf drop accentuates the expected TM 4/3 and TM 5/4 changes.

Development of a small-sized generator of ozonated water using an electro-conductive diamond electrode.

PubMed

Sekido, Kota; Kitaori, Noriyuki

2008-12-01

A small-sized generator of ozonated water was developed using an electro-conductive diamond. We studied the optimum conditions for producing ozonated water. As a result, we developed a small-sized generator of ozonated water driven by a dry-cell for use in the average household. This generator was easily able to produce ozonated water with an ozone concentration (over 4 mg/L) sufficient for disinfection. In addition, we verified the high disinfecting performance of the water produced in an actual hospital.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shertz, R.D.; Kender, W.J.; Musselman, R.C.

Three cultivars of greenhouse-grown apple trees (Malus domestica, Borkh.) were fumigated for single, 4-hour exposures with ozone (O/sub 3/) and/or sulfur dioxide (SO/sub 2/) at 0.40 and 0.80 ppm. Fumigations were performed in a plexiglass chamber situated within a controlled environment walk-in growth chamber. All 3 cultivars responded to treatments in a similar manner. When applied separately both gases induced characteristic foliar injury. In general, apple trees were more sensitive to 0.40 ppm O/sub 3/ than to 0.40 ppm SO/sub 2/; but they responded similarly to 0.80 ppm O/sub 3/ or SO/sub 2/. Foliar injury, leaf abscission, and shoot growthmore » reduction were greatest when 0.80 ppm O/sub 3/ and 0.80 ppm SO/sub 2/ were combined. The data showed a less-than additive response when the 2 pollutants were combined; a response due, in part, to the high amount of injury induced by single pollutants at these concentrations. All O/sub 3/ and/or SO/sub 2/ fumigations resulted in stomatal closure.« less

A Study on Generation Ice Containing Ozone

NASA Astrophysics Data System (ADS)

Yoshimura, Kenji; Koyama, Shigeru; Yamamoto, Hiromi

Ozone has the capability of sterilization and deodorization due to high oxidation power. It is also effective for the conservation of perishable foods and purification of water. However, ozone has a disadvantage, that is, conservation of ozone is difficult because it changes back into oxygen. Recently, ice containing ozone is taken attention for the purpose of its conservation. The use of ice containing ozone seems to keep food fresher when we conserve and transport perishable foods due to effects of cooling and sterilization of ice containing ozone. In the present study, we investigated the influence of temperatures of water dissolving ozone on the timewise attenuations of ozone concentration in water. We also investigated the influence of cooling temperature, ice diameter, initial temperatures of water dissolving ozone and container internal pressure of the water dissolving ozone on ozone concentration in the ice. In addition, we investigated the influence of the ice diameter on the timewise attenuations of ozone concentration in the ice. It was confirmed that the solidification experimental data can be adjusted by a correlation between ozone concentration in the ice and solidification time.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tanada, Seiki; Nakamura, Takeo; Xiaohong, Ma

Trichloroethylene (TCE) and 1,1,1-trichloroethane (methylchloroform:MC) are major volatile chlorinated hydrocarbons, and the production amounts of these compounds run up to about 80,000-100,000 tons a year in Japan. TCE and MC were observed in groundwater in Japan as well as in the United States, so that the environmental contamination by these compounds became a serious problem. TCE and MC cause vertigo, headache, drunkenness and fatigue depending on central nervous system depress, and also liver or kidney lesion by inhalation as general toxicities. For prevention of the poisoning to workers, the permissible concentrations of TCE and MC vapors in work area havemore » been set at 50ppm and 200ppm, respectively by Japan Association of Industrial Health. In the United States, those values are set at 100ppm and 350ppm by American Conference of Governmental Industrial Hygienists, respectively. In addition, TCE is considered to be carcinogenic because it causes liver cancer in mice. Furthermore, MC is considered to destroy the Ozone Layer. Though it is presumed that 40-70% of used TCE and MC in factories is exhausted to the atmosphere, there is no regulation now concerning the exhaustion of TCE and MC to the atmosphere. So that regards should be paid to the intake of TCE and MC from the atmosphere as well as from drinking water. In this paper, we studied the adsorption removal of TCE and MC by activated carbon fibers (ACFs) in gaseous phase pointing to the prevention against TCE and MC diffusion to the atmosphere and inhalation to workers. 9 refs., 3 figs., 2 tabs.« less

Field responses of Prunus serotina and Asclepias syriaca to ozone around southern Lake Michigan.

PubMed

Bennett, J P; Jepsen, E A; Roth, J A

2006-07-01

Higher ozone concentrations east of southern Lake Michigan compared to west of the lake were used to test hypotheses about injury and growth effects on two plant species. We measured approximately 1000 black cherry trees and over 3000 milkweed stems from 1999 to 2001 for this purpose. Black cherry branch elongation and milkweed growth and pod formation were significantly higher west of Lake Michigan while ozone injury was greater east of Lake Michigan. Using classification and regression tree (CART) analyses we determined that departures from normal precipitation, soil nitrogen and ozone exposure/peak hourly concentrations were the most important variables affecting cherry branch elongation, and milkweed stem height and pod formation. The effects of ozone were not consistently comparable with the effects of soil nutrients, weather, insect or disease injury, and depended on species. Ozone SUM06 exposures greater than 13 ppm-h decreased cherry branch elongation 18%; peak 1-h exposures greater than 93 ppb reduced milkweed stem height 13%; and peak 1-h concentrations greater than 98 ppb reduced pod formation 11% in milkweed.

Evaluation of ozonated water using ASTM E1174 for standardized testing of handwash formulations for healthcare personnel.

PubMed

Nakamura, K; Saito, K; Kashiwazaki, J; Aoyagi, T; Arai, K; Hara, Y; Kobari, S; Mori, H; Ohashi, K; Takano, Y; Kaku, M; Kanemitsu, K

2018-02-13

Removal of bacteria by handwashing with ozonated water was evaluated using the ASTM E1174 standard test method. Thirty healthy volunteers were assigned randomly to three groups: ozonated water, antimicrobial soap and water, and non-antimicrobial soap and water. A 3 log 10  cfu reduction was achieved by washing hands with ozonated water or antimicrobial soap and water. However, ozonated water was not significantly superior to non-antimicrobial soap and water. Ozonated water may remove bacteria from the hands to at least a similar extent as that by non-antimicrobial soap and water in the absence of visible dirt or body fluid contamination. Copyright © 2018 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Adrenal-derived stress hormones modulate ozone-induced ...

EPA Pesticide Factsheets

Ozone-induced systemic effects are modulated through activation of the neuro-hormonal stress response pathway. Adrenal demedullation (DEMED)or bilateral total adrenalectomy (ADREX) inhibits systemic and pulmonary effect of acute ozone exposure. To understand the influence of adrenal-derived stress hormones in mediating ozone-induced lung injury/inflammation, we assessed global gene expression (mRNA sequencing) and selected proteins in lung tissues from male Wistar-Kyoto rats that underwent DEMED, ADREX, or sham surgery (SHAM)prior to their exposure to air or ozone (1 ppm),4 h/day for 1 or 2days. Ozone exposure significantly changed the expression of over 2300 genes in lungs of SHAM rats, and these changes were markedly reduced in DEMED and ADREX rats. SHAM surgery but not DEMED or ADREX resulted in activation of multiple ozone-responsive pathways, including glucocorticoid, acute phase response, NRF2, and Pl3K-AKT.Predicted targets from sequencing data showed a similarity between transcriptional changes induced by ozone and adrenergic and steroidal modulation of effects in SHAM but not ADREX rats. Ozone-induced Increases in lung 116 in SHAM rats coincided with neutrophilic Inflammation, but were diminished in DEMED and ADREX rats. Although ozone exposure in SHAM rats did not significantly alter mRNA expression of lfny and 11-4, the IL-4 protein and ratio of IL-4 to IFNy (IL-4/IFNy) proteins increased suggesting a tendency for a Th2 response. This did not occur

Novel Roles for Notch3 and Notch4 Receptors in Gene Expression and Susceptibility to Ozone-Induced Lung Inflammation in Mice.

PubMed

Verhein, Kirsten C; McCaw, Zachary; Gladwell, Wesley; Trivedi, Shweta; Bushel, Pierre R; Kleeberger, Steven R

2015-08-01

Ozone is a highly toxic air pollutant and global health concern. Mechanisms of genetic susceptibility to ozone-induced lung inflammation are not completely understood. We hypothesized that Notch3 and Notch4 are important determinants of susceptibility to ozone-induced lung inflammation. Wild-type (WT), Notch3 (Notch3-/-), and Notch4 (Notch4-/-) knockout mice were exposed to ozone (0.3 ppm) or filtered air for 6-72 hr. Relative to air-exposed controls, ozone increased bronchoalveolar lavage fluid (BALF) protein, a marker of lung permeability, in all genotypes, but significantly greater concentrations were found in Notch4-/- compared with WT and Notch3-/- mice. Significantly greater mean numbers of BALF neutrophils were found in Notch3-/- and Notch4-/- mice compared with WT mice after ozone exposure. Expression of whole lung Tnf was significantly increased after ozone in Notch3-/- and Notch4-/- mice, and was significantly greater in Notch3-/- compared with WT mice. Statistical analyses of the transcriptome identified differentially expressed gene networks between WT and knockout mice basally and after ozone, and included Trim30, a member of the inflammasome pathway, and Traf6, an inflammatory signaling member. These novel findings are consistent with Notch3 and Notch4 as susceptibility genes for ozone-induced lung injury, and suggest that Notch receptors protect against innate immune inflammation.

Effect of ozone exposure on antigen-induced airway hyperresponsiveness in guinea pigs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vargas, M.H.; Segura, P.; Campos, M.G.

1994-12-31

Airway hyperresponsiveness can be induced by several stimuli including antigen and ozone, both of which may be present in the air of polluted cities. Though the effect of ozone on the bronchoconstrictor response to antigen has been well described, the combined effect of these stimuli on airway hyperresponsiveness has not yet been studied. Sensitized guinea pigs with or without ozone exposure for 1 h at 3 ppm, 18 h prior to study, were challenged with a dose-response curve to histamine (0.01-1.8 {mu}g/kg, iv), and then by a second histamine dose-response curve 1 h later. Airway responses were measured as themore » increase in pulmonary insufflation pressure. In sensitized guinea pigs, the histamine ED50 significantly decreased after antigen challenge, demonstrating the development of airway hyperresponsiveness. Sensitized guinea pigs exposed to ozone showed airway hyperresponsiveness to histamine when compared with nonexposed animals, and such hyperresponsiveness was further enhanced after antigen challenge. We conclude that in this guinea pig model of acute allergic bronchoconstriction both antigen challenge and ozone induce airway hyperresponsiveness, while ozone exposure does not modify the development of antigen-induced hyperresponsiveness. 25 refs., 1 fig., 1 tab.« less

Inhaled ozone (O{sub 3})-induces changes in serum metabolomic and liver transcriptomic profiles in rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Desinia B.; Karoly, Edward D.; Jones, Jan C.

Air pollution has been linked to increased incidence of diabetes. Recently, we showed that ozone (O{sub 3}) induces glucose intolerance, and increases serum leptin and epinephrine in Brown Norway rats. In this study, we hypothesized that O{sub 3} exposure will cause systemic changes in metabolic homeostasis and that serum metabolomic and liver transcriptomic profiling will provide mechanistic insights. In the first experiment, male Wistar Kyoto (WKY) rats were exposed to filtered air (FA) or O{sub 3} at 0.25, 0.50, or 1.0 ppm, 6 h/day for two days to establish concentration-related effects on glucose tolerance and lung injury. In a secondmore » experiment, rats were exposed to FA or 1.0 ppm O{sub 3}, 6 h/day for either one or two consecutive days, and systemic metabolic responses were determined immediately after or 18 h post-exposure. O{sub 3} increased serum glucose and leptin on day 1. Glucose intolerance persisted through two days of exposure but reversed 18 h-post second exposure. O{sub 3} increased circulating metabolites of glycolysis, long-chain free fatty acids, branched-chain amino acids and cholesterol, while 1,5-anhydroglucitol, bile acids and metabolites of TCA cycle were decreased, indicating impaired glycemic control, proteolysis and lipolysis. Liver gene expression increased for markers of glycolysis, TCA cycle and gluconeogenesis, and decreased for markers of steroid and fat biosynthesis. Genes involved in apoptosis and mitochondrial function were also impacted by O{sub 3}. In conclusion, short-term O{sub 3} exposure induces global metabolic derangement involving glucose, lipid, and amino acid metabolism, typical of a stress–response. It remains to be examined if these alterations contribute to insulin resistance upon chronic exposure. - Highlights: • Ozone, an ubiquitous air pollutant induces acute systemic metabolic derangement. • Serum metabolomic approach provides novel insights in ozone-induced changes. • Ozone exposure induces leptinemia, hyperglycemia, and glucose intolerance. • Ozone increases serum free fatty acids, branched chain amino acids, cholesterols. • Ozone metabolic derangement is likely mediated by neuronal stress response pathway.« less

Pulmonary function adaptation to ozone in subjects with chronic bronchitis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kulle, T.J.; Milman, J.H.; Sauder, L.R.

Twenty smokers with chronic bronchitis were exposed to 0.41 ppm ozone for 3 hr-day for 5 consecutive days and reexposed 4 days later to determine (1) if they are sensitive to ozone, (2) if they adapt, and (3) if the adaptation lasts longer than 4 days. There were significant decrements in forced vital capacity (FVC) and forced expiratory volume in 3 sec (FEV/sub 3/) on the first day of the 5-day repeated exposures and also on reexposure 4 days following cessation of the sequential exposures. Symptoms experienced were mild and did not predominate on any exposure days. These results suggestmore » that individuals with chronic bronchitis adapt rapidly to ozone and lose this adaptive phenomenon within 4 days. The small decreases seen in FVC and FEV/sub 3/ ( less than or equal to 3%) appear to impose no more than minimal limitations on their daily activities.« less

Pulmonary function adaptation to ozone in subjects with chronic bronchitis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kulle, T.J.; Milman, J.H.; Sauder, L.R.

Twenty smokers with chronic bronchitis were exposed to 0.41 ppm ozone for 3 hr-day for 5 consecutive days and reexposed 4 days later to determine (1) if they are sensitive to ozone, (2) if they adapt, and (3) if the adaptation lasts longer than 4 days. There were significant decrements in forced vital capacity (FVC) and forced expiratory volume in 3 sec (FEV3) on the first day of the 5-day repeated exposures and also on reexposure 4 days following cessation of the sequential exposures. Symptoms experienced were mild and did not predominate on any exposure days. These results suggest thatmore » individuals with chronic bronchitis adapt rapidly to ozone and lose the adaptive phenomenon within 4 days. The small decreases seen in FVC and FEV3 appear to impose no more than minimal limitations on their daily activities.« less

Effects of ozone and ozone/peroxide on trace organic contaminants and NDMA in drinking water and water reuse applications.

PubMed

Pisarenko, Aleksey N; Stanford, Benjamin D; Yan, Dongxu; Gerrity, Daniel; Snyder, Shane A

2012-02-01

An ozone and ozone/peroxide oxidation process was evaluated at pilot scale for trace organic contaminant (TOrC) mitigation and NDMA formation in both drinking water and water reuse applications. A reverse osmosis (RO) pilot was also evaluated as part of the water reuse treatment train. Ozone/peroxide showed lower electrical energy per order of removal (EEO) values for TOrCs in surface water treatment, but the addition of hydrogen peroxide increased EEO values during wastewater treatment. TOrC oxidation was correlated to changes in UV(254) absorbance and fluorescence offering a surrogate model for predicting contaminant removal. A decrease in N-nitrosodimethylamine (NDMA) formation potential (after chloramination) was observed after treatment with ozone and ozone/peroxide. However, during spiking experiments with surface water, ozone/peroxide achieved limited destruction of NDMA, while in wastewaters net direct formation of NDMA of 6-33 ng/L was observed after either ozone or ozone/peroxide treatment. Once formed during ozonation, NDMA passed through the subsequent RO membranes, which highlights the significance of the potential for direct NDMA formation during oxidation in reuse applications. Copyright © 2011 Elsevier Ltd. All rights reserved.

Power consumption analysis DBD plasma ozone generator

NASA Astrophysics Data System (ADS)

Nur, M.; Restiwijaya, M.; Muchlisin, Z.; Susan, I. A.; Arianto, F.; Widyanto, S. A.

2016-11-01

Studies on the consumption of energy by an ozone generator with various constructions electrodes of dielectric barrier discharge plasma (DBDP) reactor has been carried out. This research was done to get the configuration of the reactor, that is capable to produce high ozone concentrations with low energy consumption. BDBP reactors were constructed by spiral- cylindrical configuration, plasma ozone was generated by high voltage AC voltage up to 25 kV and maximum frequency of 23 kHz. The reactor consists of an active electrode in the form of a spiral-shaped with variation diameter Dc, and it was made by using copper wire with diameter Dw. In this research, we variated number of loops coil windings N as well as Dc and Dw. Ozone concentrations greater when the wire's diameter Dw and the diameter of the coil windings applied was greater. We found that impedance greater will minimize the concentration of ozone, in contrary to the greater capacitance will increase the concentration of ozone. The ozone concentrations increase with augmenting of power. Maximum power is effective at DBD reactor spiral-cylinder is on the Dc = 20 mm, Dw = 1.2 mm, and the number of coil windings N = 10 loops with the resulting concentration is greater than 20 ppm and it consumes energy of 177.60 watts

Mechanisms of ozone toxicity in cultured cells. I. Reduced clonogenic ability of polyunsaturated fatty acid-supplemented fibroblasts. Effect of vitamin E

DOE Office of Scientific and Technical Information (OSTI.GOV)

Konings, A.W.

1986-01-01

The direct action of ozone on viability and survival of normal and modified mouse lung fibroblasts has been studied. By cell manipulation of fibroblasts in culture, the content of polyunsaturated fatty acids (PUFA) in the phospholipids was increased from about 6% to about 40%. The cellular content of alpha-tocopherol (alpha-T) (vitamin E) could be drastically enhanced. Vitamin E supplementation to the cell did not influence the PUFA manipulation. Normal, PUFA, and PUFA(alpha-T) fibroblasts were exposed to ozone by bubbling 10 ppm through the cell suspensions for different periods of time (0-6 h). No significant effects of the ozone exposure couldmore » be established when normal fibroblasts were used. The PUFA fibroblasts, however, were very vulnerable to ozone toxicity, both in terms of dye uptake (Trypan blue) and cell death (clonogenic ability). When alpha-tocopherol was present in the cell (200 ng/10(6) cells), a clear protection against ozone toxicity was found. It is concluded that ozone toxicity might be higher under conditions of a relative high amount of polyunsaturated fatty acids in the membrane phospholipids of the cell and a low cellular antioxidant capacity. Cellular membranes are probably an important target for ozone-induced cell death.« less

Oxygen isotope anomaly observed in water vapor from Alert, Canada and the implication for the stratosphere

PubMed Central

Lin, Ying; Clayton, Robert N.; Huang, Lin; Nakamura, Noboru; Lyons, James R.

2013-01-01

To identify the possible anomalous oxygen isotope signature in stratospheric water predicted by model studies, 25 water vapor samples were collected in 2003−2005 at Alert station, Canada (82°30′N), where there is downward transport of stratospheric air to the polar troposphere, and were analyzed for δ17O and δ18O relative to Chicago local precipitation (CLP). The latter was chosen as a reference because the relatively large evaporative moisture source should erase any possible oxygen isotope anomaly from the stratosphere. A mass-dependent fractionation coefficient for meteoric waters, λMDF(H2O) = 0.529 ± 0.003 [2σ standard error (SE)], was determined from 27 CLP samples collected in 2003−2005. An oxygen isotopic anomaly of Δ17O = 76 ± 16 ppm (2σ SE) was found in water vapor samples from Alert relative to CLP. We propose that the positive oxygen isotope anomalies observed at Alert originated from stratospheric ozone, were transferred to water in the stratosphere, and subsequently mixed with tropospheric water at high latitudes as the stratospheric air descended into the troposphere. On the basis of this ground signal, the average Δ17O in stratospheric water vapor predicted by a steady-state box model is ∼40‰. Seven ice core samples (1930−1991) from Dasuopu glacier (Himalayas, China) and Standard Light Antarctic Precipitation did not show an obvious oxygen isotope anomaly, and Vienna Standard Mean Ocean Water exhibited a negative Δ17O relative to CLP. Six Alert snow samples collected in March 2011 and measured at Laboratoire des Sciences du Climat et de l'Environnement, Gif sur Yvette, France, had 17Oexcess of 45 ± 5 ppm (2σ SE) relative to Vienna Standard Mean Ocean Water. PMID:24009339

Ozone assisted oxidation of gaseous PCDD/Fs over CNTs-containing composite catalysts at low temperature.

PubMed

Wang, Qiulin; Tang, Minghui; Peng, Yaqi; Du, Cuicui; Lu, Shengyong

2018-05-01

Ozone assisted carbon nanotubes (CNTs) supported vanadium oxide/titanium dioxide (V/Ti-CNTs) or vanadium oxide-manganese oxide/titanium dioxide (V-Mn/Ti-CNTs) catalysts towards gaseous PCDD/Fs (polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans) catalytic oxidations at low temperature (150 °C) were investigated. The removal efficiency (RE) and decomposition efficiency (DE) of PCDD/Fs achieved with V-Mn/Ti-CNTs alone were 95% and 45% at 150 °C under a space velocity (SV) of 14000 h -1 ; yet, these values reached 99% and 91% when catalyst and low concentration (50 ppm) ozone were used in combined. The ozone promotion effect on catalytic activity was further enhanced with the addition of manganese oxide (MnO x ) and CNTs. Adding MnO x and CNTs in V/Ti catalysts facilitated the ozone decomposition (creating more active species on catalyst surface), thus, improved ozone utilization (demanding relatively lower ozone addition concentration). On the other hand, this study threw light upon ozone promotion mechanism based on the comparison of catalyst properties (i.e. components, surface area, surface acidity, redox ability and oxidation state) before and after ozone treatment. The experimental results indicate that a synergistic effect exists between catalyst and ozone: ozone is captured and decomposed on catalyst surface; meanwhile, the catalyst properties are changed by ozone in return. Reactive oxygen species from ozone decomposition and the accompanied catalyst properties optimization are crucial reasons for catalyst activation at low temperature. Copyright © 2018 Elsevier Ltd. All rights reserved.

Pulmonary effects of inhaled limonene ozone reaction products in elderly rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sunil, Vasanthi R.; Laumbach, Robert J.; Patel, Kinal J.

2007-07-15

d-Limonene is an unsaturated volatile organic chemical found in cleaning products, air fresheners and soaps. It is oxidized by ozone to secondary organic aerosols consisting of aldehydes, acids, oxidants and fine and ultra fine particles. The lung irritant effects of these limonene ozone reaction products (LOP) were investigated. Female F344 rats (2- and 18-month-old) were exposed for 3 h to air or LOP formed by reacting 6 ppm d-limonene and 0.8 ppm ozone. BAL fluid, lung tissue and cells were analyzed 0 h and 20 h later. Inhalation of LOP increased TNF-{alpha}, cyclooxygenase-2, and superoxide dismutase in alveolar macrophages (AM)more » and Type II cells. Responses of older animals were attenuated when compared to younger animals. LOP also decreased p38 MAP kinase in AM from both younger and older animals. In contrast, while LOP increased p44/42 MAP kinase in AM from younger rats, expression decreased in AM and Type II cells from older animals. NF-{kappa}B and C/EBP activity also increased in AM from younger animals following LOP exposure but decreased or was unaffected in Type II cells. Whereas in younger animals LOP caused endothelial cell hypertrophy, perivascular and pleural edema and thickening of alveolar septal walls, in lungs from older animals, patchy accumulation of fluid within septal walls in alveolar sacs and subtle pleural edema were noted. LOP are pulmonary irritants inducing distinct inflammatory responses in younger and older animals. This may contribute to the differential sensitivity of these populations to pulmonary irritants.« less

Vitamin E antagonizes ozone-induced asthma exacerbation in Balb/c mice through the Nrf2 pathway.

PubMed

Duan, Liju; Li, Jinquan; Ma, Ping; Yang, Xu; Xu, Shunqing

2017-09-01

Millions of people are regularly exposed to ozone, a gas known to contribute significantly to worsening the symptoms of patients with asthma. However, the mechanisms underlying these ozone exacerbation effects are not fully understood. In this study, we examined the exacerbation effect of ozone in OVA-induced asthma mice and tried to demonstrate the protective mechanism of vitamin E (VE). An asthma mouse model was established, and used to identify the exacerbating effects of ozone by assessing cytokine and serum immunoglobulin concentrations, airway leukocyte infiltration, histopathological changes in lung tissues, and airway hyper-responsiveness. We then determined the amount of reactive oxygen species (ROS) accumulated, the extent to which VE induced ROS elimination, and examined the antagonistic effects of VE on the ozone-induced exacerbating effects. This study showed that 1-ppm ozone exposure could exacerbate OVA-induced asthma in mice. More importantly we found that ozone induced oxidative stress in asthmatic airways may lead to the inhibition of Nuclear factor-erythroid 2-related factor 2 (Nrf2), and may subsequently induce even more exaggerated oxidative stress associated with asthma exacerbation. Through VE induced Nrf2 activation and the subsequent increase in Nrf2 target protein expression, this study suggests a novel mechanism for alleviating ozone exacerbated asthma symptoms. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dual p38/JNK Mitogen Activated Protein Kinase Inhibitors Prevent Ozone-Induced Airway Hyperreactivity in Guinea Pigs

PubMed Central

Verhein, Kirsten C.; Salituro, Francesco G.; Ledeboer, Mark W.; Fryer, Allison D.; Jacoby, David B.

2013-01-01

Ozone exposure causes airway hyperreactivity and increases hospitalizations resulting from pulmonary complications. Ozone reacts with the epithelial lining fluid and airway epithelium to produce reactive oxygen species and lipid peroxidation products, which then activate cell signaling pathways, including the mitogen activated protein kinase (MAPK) pathway. Both p38 and c-Jun NH2 terminal kinase (JNK) are MAPK family members that are activated by cellular stress and inflammation. To test the contribution of both p38 and JNK MAPK to ozone-induced airway hyperreactivity, guinea pigs were pretreated with dual p38 and JNK MAPK inhibitors (30 mg/kg, ip) 60 minutes before exposure to 2 ppm ozone or filtered air for 4 hours. One day later airway reactivity was measured in anesthetized animals. Ozone caused airway hyperreactivity one day post-exposure, and blocking p38 and JNK MAPK completely prevented ozone-induced airway hyperreactivity. Blocking p38 and JNK MAPK also suppressed parasympathetic nerve activity in air exposed animals, suggesting p38 and JNK MAPK contribute to acetylcholine release by airway parasympathetic nerves. Ozone inhibited neuronal M2 muscarinic receptors and blocking both p38 and JNK prevented M2 receptor dysfunction. Neutrophil influx into bronchoalveolar lavage was not affected by MAPK inhibitors. Thus p38 and JNK MAPK mediate ozone-induced airway hyperreactivity through multiple mechanisms including prevention of neuronal M2 receptor dysfunction. PMID:24058677

Calibration of equipment for analysis of drinking water fluoride: a comparison study.

PubMed

Quock, Ryan L; Chan, Jarvis T

2012-03-01

Current American Dental Association evidence-based recommendations for prescription of dietary fluoride supplements are based in part on the fluoride concentration of a pediatric patient's drinking water. With these recommendations in mind, this study compared the relative accuracy of fluoride concentration analysis when a common apparatus is calibrated with different combinations of standard values. Fluoride solutions in increments of 0.1 ppm, from a range of 0.1 to 1.0 ppm fluoride, as well as 2.0 and 4.0 ppm, were gravimetrically prepared and fluoride concentration measured in pentad, using a fluoride ion-specific electrode and millivolt meter. Fluoride concentrations of these solutions were recorded after calibration with the following 3 different combinations of standard fluoride solutions: 0.1 ppm and 0.5 ppm, 0.1 ppm and 1.0 ppm, 0.5 ppm and 1.0 ppm. Statistical analysis showed significant differences in the fluoride content of water samples obtained with different two-standard fluoride solutions. Among the two-standard fluoride solutions tested, using 0.5 ppm and 1.0 ppm as two-standard fluoride solutions provided the most accurate fluoride measurement of water samples containing fluoride in the range of 0.1 ppm to 4.0 ppm. This information should be valuable to dental clinics or laboratories in fluoride analysis of drinking water samples.

Environmental Assessment for Beddown of Air Force Reserve Command Classic Associate Unit on A/OA-10 Operations and Maintenance Moody Air Force Base, Georgia

DTIC Science & Technology

2008-09-01

Code of Federal Regulations CO carbon monoxide CSAF Chief of Staff of the Air Force dB decibels DNL day-night average sound level DNLmr onset rate...the health and welfare of the general public. These seven pollutants (the “criteria pollutants”) include ozone, carbon monoxide (CO), nitrogen... Monoxide 9 ppm (10 mg/m3) 8-hour (1) None 35 ppm (40 mg/m3) 1-hour (1) None Lead 1.5 µg/m3 Quarterly Average Same as Primary Nitrogen Dioxide 0.053

Ozone Antimicrobial Efficacy

EPA Science Inventory

Ozone is a potent germicide that has been used extensively for water purification. In Europe, 90 percent of the municipal water systems are treated with ozone, and in France, ozone has been used to treat drinking water since 1903. However, there is limited information on the bioc...

Scientific Studies in Association with the Halogen Occultation Experiment

NASA Technical Reports Server (NTRS)

Mickley, Lorretta J.; Frederick, John E.

1996-01-01

This work examines measurements of ozone, NO, NO2, and HCl made by the Halogen Occultation Experiment (HALOE) to track chemical change in the stratosphere. In addition, HALOE observations of two long-lived species, HF and CH4, are used as tracers to distinguish between change due to transport processes and change due to chemistry. The first study investigates the response of NO(x), (NO and NO2) and ozone to the presence of large amounts of sulfate aerosol in the stratosphere following the 1991 eruption of Mount Pinatubo. As the Pinatubo aerosol cleared the atmosphere at 17 mb (about 27-28 km), the partitioning of total reactive nitrogen shifted more toward NO(x), and ozone amounts declined. This trend is opposite that observed at lower altitudes. The second study examines the chemical aftermath of severe ozone depletion over Antarctica in spring. When ozone levels drop to a threshold amount (about 1 ppm near 20 km), the partitioning of the total chlorine family shifts rapidly from reactive species to the reservoir molecule HCl. This sudden repartitioning shuts down further ozone loss and may be significant as filaments of air peel off the polar vortex and mix with mid-latitude air.

Effects of age, socioeconomic status, and menstrual cycle on pulmonary response to ozone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seal, E. Jr.; McDonnell, W.F.; House, D.E.

The purpose of this study was to investigate the effects of age, socioeconomic status, and menstrual cycle phase on the pulmonary response to ozone exposure. Three hundred seventy-two healthy white and black young adults, between the ages of 18 and 35 y, were exposed only once to 0.0, 0.12, 0.18, 0.24, 0.30, or 0.40 ppm ozone for 2.3 h. Prior to and after exposure, pulmonary function tests were obtained. Prior to exposure, each subject completed a personal and family-history questionnaire. The response to this questionnaire were used to investigate age, socioeconomic status, and menstrual cycle phase effects on pulmonary responsivenessmore » to ozone. We concluded that the ages of subjects, within the age range studied, had an effect on responsiveness (i.e., decrements in forced expiratory volume in 1 s decreased as the subjects` ages decreased). Socioeconomic status, as reflected by education of fathers, also appeared to affect forced expiratory volume in 1-s responsiveness to ozone, with the middle socioeconomic group being the most responsive. The phase of menstrual cycle did not have an impact on individual responsiveness to ozone. 14 refs., 4 figs.« less

Ozone-initiated disinfection kinetics of Escherichia coli in water.

PubMed

Zuma, Favourite; Lin, Johnson; Jonnalagadda, Sreekanth B

2009-01-01

The effect of ozonation on the rate of disinfection of Escherichia coli was investigated as a function of ozone concentration, ozonation duration and flow rates. Ozone was generated in situ using Corona discharge method using compressed oxygen stream and depending on the oxygen flux the ozone concentrations ranged from 0.91-4.72 mg/L. The rate of disinfection of all the three microbes followed pseudo-first-order kinetics with respect to the microbe count and first order with respect to ozone concentration. The influence of pH and temperature the aqueous systems on the rate of ozone initiated disinfection of the microbe was investigated. The inactivation was faster at lower pH than at basic pH. Molecular ozone is found more effective in disinfection than hydroxyl radicals. Two reported mechanisms for antimicrobial activity of ozone in water systems from the literature are discussed. Based on the experimental findings a probable rate law and mechanism are proposed. Ozonation of natural waters significantly decreased the BOD levels of the control and microbe contaminated waters.

[Effect of ozone on membrane fouling in water and wastewater treatment: a research review].

PubMed

Zhu, Hong-tao; Wen, Xiang-hua; Huang, Xia

2009-01-01

As a high efficient water and wastewater treatment technology, membrane filtration has been mainly used in wastewater treatment as membrane bioreactor, in reclaiming secondary effluent,treating surface water and potable water, and etc. Membrane fouling is a main obstacle to the wide application of membrane technology. Ozone has strong oxidizing power and has been utilized widely in water and wastewater treatment. In recent years, researches on combined process of ozone-membrane filtration are increasing. This paper does reviews and analysis of these researches. It is noticed that there has been a few of researches on the ozone treatment plus MBR process. Pre-ozonation of feed to MBR and slight ozonation of the mixed liquid in MBR may be used to relieve membrane fouling.Combined processes of ozone-membrane filtration can be divided into three classes in terms of the function of ozone and the system configuration: (1) cleaning the fouled membrane with ozone; (2) separate ozone-membrane filtration process; (3) integrated ozone-membrane filtration process. Although most reports supported that ozonation can control membrane fouling development,there were contrary results. At present, researches on the mechanisms of ozone's effect on membrane fouling control concentrated on the change of organic composition of the filtration influent under ozonation, however, particulate substances, microbial and inorganic substances may also be affected and then play roles in membrane fouling, depending on source water quality and process configuration. Moreover, there have not been common parameters to evaluate the ozone diffusion equipment and efficiency. The authors suggest that further researches should emphasize on integrated ozone-membrane process, and more attention should be paid to the cost-effectiveness of the combined process.

TRPA1 mediates changes in heart rate variability and cardiac ...

EPA Pesticide Factsheets

Short-term exposure to ambient air pollution is linked with adverse cardiovascular effects. While previous research focused primarily on particulate matter-induced responses, gaseous air pollutants also contribute to cause short-term cardiovascular effects. Mechanisms underlying such effects have not been adequately described; however, the immediate nature of the response suggests involvement of irritant neural activation and downstream autonomic dysfunction. Thus, this study examines the role of TRPA1, an irritant sensory receptor found in the airways, in the cardiac response of mice to acrolein and ozone. Conscious unrestrained wild-type C57BL/6 (WT) and TRPA1 knockout (KO) mice implanted with radiotelemeters were exposed once to 3ppm acrolein, 0.3ppm ozone, or filtered air. Heart rate (HR) and electrocardiogram (ECG) were recorded continuously before, during and after exposure. Analysis of ECG morphology, incidence of arrhythmia and heart rate variability (HRV) were performed. Cardiac mechanical function was assessed using a Langendorff perfusion preparation 24h post-exposure. Acrolein exposure increased HRV independent of HR, as well as incidence of arrhythmia. Acrolein also increased left ventricular developed pressure in WT mice at 24h post-exposure. Ozone did not produce any changes in cardiac function. Neither gas produced ECG effects, changes in HRV, arrhythmogenesis, or mechanical function in KO mice. These data demonstrate that a single exposure to ac

Mexico City's active photochemistry: conclusions from the MCMA-2003 study

NASA Astrophysics Data System (ADS)

Brune, W.; Shirley, T.; Lesher, R.; Mao, J.; Volkamer, R.; Molina, L.; Molina, M.; Velasco, E.; Westberg, H.; Lamb, B.; Jobson, T.; Alexander, M.; Gonzalez, B. C.

2004-12-01

Mexico City Metropolitan Area's active photochemistry was studied using an extensive suite of measurements on the CENICA environmental laboratory's roof, as part of the MCMA-2003 field study. Intense morning sunlight photolyzed HONO and HCHO, producing hydrogen oxides (OH and HO2) at high rates. The HOx interacted with rush-hour volatile organic compounds (VOCs) and nitrogen oxides (NOx), amplifying the production rate of ozone and nitric acid. With typically 100 ppbv of NOx and 1 ppmC of VOCs, ozone production rates exceeded 30 ppbv/hour, routinely creating in excess of 150 ppbv of ozone, even though the midday mixed layer was more than 3 km deep. Analyses of glyoxal, a product of VOC oxidation, and the hydroperoxyl radical (HO2) indicate that MCMA's ozone production was VOC-limited during morning rush hour, when typically 1/2 of the ozone is produced, and for a significant number of days during midday and afternoon at the site. Aspects of Mexico City's active photochemistry will be compared to the observed photochemistry in U.S. urban areas.

Sterilization of Microorganisms by Ozone and Ultrasound

NASA Astrophysics Data System (ADS)

Krasnyj, V. V.; Klosovskij, A. V.; Panasko, T. A.; Shvets, O. M.; Semenova, O. T.; Taran, V. S.; Tereshin, V. I.

2008-03-01

The results of recent experimental methods of sterilization of microorganisms with the use of ozone and ultrasound are presented. The main aim was to optimize the process of sterilization in water solution taking into account the ozone concentration, the power of ultrasonic emitter and the temperature of water. In the present work, the ultrasonic cavitation with simultaneous ozone generation has been used. The high ozone concentration in water solution was achieved by two-barrier glow discharge generated at atmospheric pressure and a cooling thermo-electric module. Such a sterilizer consists of ozone generator in a shape of flat electrodes covered with dielectric material and a high-voltage pulsed power supply of 250 W. The sterilization camera was equipped with ultrasonic source operated at 100 W. The experiments on the inactivation of bacteria of the Bacillus Cereus type were carried out in the distilled water saturated by ozone. The ozone concentration in the aqueous solution was 10 mg/1, whereas the ozone concentration at the output of ozone generator was 30 mg/1. The complete inactivation of spores took 15 min. Selection of the temperature of water, the ozone concentrations and ultrasonic power allowed to determine the time necessary for destroying the row of microorganisms.

Persistent rhinitis and epithelial remodeling induced by cyclic ozone exposure in the nasal airways of infant monkeys

PubMed Central

Ballinger, Carol A.; Plopper, Charles G.; McDonald, Ruth J.; Bartolucci, Alfred A.; Postlethwait, Edward M.; Harkema, Jack R.

2011-01-01

Children chronically exposed to high levels of ozone (O3), the principal oxidant pollutant in photochemical smog, are more vulnerable to respiratory illness and infections. The specific factors underlying this differential susceptibility are unknown but may be related to air pollutant-induced nasal alterations during postnatal development that impair the normal physiological functions (e.g., filtration and mucociliary clearance) serving to protect the more distal airways from inhaled xenobiotics. In adult animal models, chronic ozone exposure is associated with adaptations leading to a decrease in airway injury. The purpose of our study was to determine whether cyclic ozone exposure induces persistent morphological and biochemical effects on the developing nasal airways of infant monkeys early in life. Infant (180-day-old) rhesus macaques were exposed to 5 consecutive days of O3 [0.5 parts per million (ppm), 8 h/day; “1-cycle”] or filtered air (FA) or 11 biweekly cycles of O3 (FA days 1–9; 0.5 ppm, 8 h/day on days 10–14; “11-cycle”). The left nasal passage was processed for light microscopy and morphometric analysis. Mucosal samples from the right nasal passage were processed for GSH, GSSG, ascorbate (AH2), and uric acid (UA) concentration. Eleven-cycle O3 induced persistent rhinitis, squamous metaplasia, and epithelial hyperplasia in the anterior nasal airways of infant monkeys, resulting in a 39% increase in the numeric density of epithelial cells. Eleven-cycle O3 also induced a 65% increase in GSH concentrations at this site. The persistence of epithelial hyperplasia was positively correlated with changes in GSH. These results indicate that early life ozone exposure causes persistent nasal epithelial alterations in infant monkeys and provide a potential mechanism for the increased susceptibility to respiratory illness exhibited by children in polluted environments. PMID:21131400

Generation and delivery device for ozone gas and ozone dissolved in water

NASA Technical Reports Server (NTRS)

Andrews, Craig C. (Inventor); Murphy, Oliver J. (Inventor)

2004-01-01

The present invention provides an ozone generation and delivery system that lends itself to small scale applications and requires very low maintenance. The system preferably includes an anode reservoir and a cathode phase separator each having a hydrophobic membrane to allow phase separation of produced gases from water. The hydrogen gas, ozone gas and water containing ozone may be delivered under pressure.

Low Cost, Efficient Microcavity Plasma Ozone Generation for Water Remediation and Air Purification

DTIC Science & Technology

2012-06-01

Eliasson, and M. Hirth, “ Ozone Generation from Oxygen and Air: Discharge Physics and Reaction Mechanisms,” Ozone Sci. and Eng., vol. 10, pp. 367-378...Phase I Final Report: Low Cost, Efficient Microcavity Plasma Ozone Generation for Water Remediation and Air Purification...Contract Number: FA9550-11-C-0087 June 2012 Low Cost, Efficient Microcavity Plasma Ozone Generation for Water Remediation

Water purification by electrical discharges

NASA Astrophysics Data System (ADS)

Arif Malik, Muhammad; Ghaffar, Abdul; Akbar Malik, Salman

2001-02-01

There is a continuing need for the development of effective, cheap and environmentally friendly processes for the disinfection and degradation of organic pollutants from water. Ozonation processes are now replacing conventional chlorination processes because ozone is a stronger oxidizing agent and a more effective disinfectant without any side effects. However, the fact that the cost of ozonation processes is higher than chlorination processes is their main disadvantage. In this paper recent developments targeted to make ozonation processes cheaper by improving the efficiency of ozone generation, for example, by incorporation of catalytic packing in the ozone generator, better dispersion of ozone in water and faster conversion of dissolved ozone to free radicals are described. The synthesis of ozone in electrical discharges is discussed. Furthermore, the generation and plasma chemical reactions of several chemically active species, such as H2O2, Obullet, OHbullet, HO2bullet, O3*, N2*, e-, O2-, O-, O2+, etc, which are produced in the electrical discharges are described. Most of these species are stronger oxidizers than ozone. Therefore, water treatment by direct electrical discharges may provide a means to utilize these species in addition to ozone. Much research and development activity has been devoted to achieve these targets in the recent past. An overview of these techniques and important developments that have taken place in this area are discussed. In particular, pulsed corona discharge, dielectric barrier discharge and contact glow discharge electrolysis techniques are being studied for the purpose of cleaning water. The units based on electrical discharges in water or close to the water level are being tested at industrial-scale water treatment plants.}

Pre-treating water with non-thermal plasma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cho, Young I.; Fridman, Alexander; Rabinovich, Alexander

The present invention consists of a method of pre-treatment of adulterated water for distillation, including adulterated water produced during hydraulic fracturing ("fracking") of shale rock during natural gas drilling. In particular, the invention is directed to a method of treating adulterated water, said adulterated water having an initial level of bicarbonate ion in a range of about 250 ppm to about 5000 ppm and an initial level of calcium ion in a range of about 500 ppm to about 50,000 ppm, said method comprising contacting the adulterated water with a non-thermal arc discharge plasma to produce plasma treated water havingmore » a level of bicarbonate ion of less than about 100 ppm. Optionally, the plasma treated water may be further distilled.« less

Modeling of experimental treatment of acetaldehyde-laden air and phenol-containing water using corona discharge technique.

PubMed

Faungnawakij, Kajornsak; Sano, Noriaki; Charinpanitkul, Tawatchai; Tanthapanichakoon, Wiwut

2006-03-01

Acetaldehyde-laden air and phenol-contaminated water were experimentally treated using corona discharge reactions and gas absorption in a single water-film column. Mathematical modeling of the combined treatment was developed in this work. Efficient removal of the gaseous acetaldehyde was achieved while the corona discharge reactions produced short-lived species such as O and O- as well as ozone. Direct contact of the radicals and ions with water was known to produce aqueous OH radical, which contributes to the decomposition of organic contaminants: phenol, absorbed acetaldehyde, and intermediate byproducts in the water. The influence of initial phenol concentration ranging from 15 to 50 mg L(-1) and that of influent acetaldehyde ranging from 0 to 200 ppm were experimentally investigated and used to build the math model. The maximum energetic efficiency of TOC, phenol, and acetaldehyde were obtained at 25.6 x 10(-9) mol carbon J(-1), 25.0 x 10(-9) mol phenol J(-1), and 2.0 x 10(-9) mol acetaldehyde J(-1), respectively. The predictions for the decomposition of acetaldehyde, phenol, and their intermediates were found to be in good agreement with the experimental results.

Chemical nature and immunotoxicological properties of arachidonic acid degradation products formed by exposure to ozone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Madden, M.C.; Friedman, M.; Hanley, N.

1993-06-01

Ozone (O3) exposure in vivo has been reported to degrade arachidonic acid (AA) in the lungs of rodents. The O3-degraded AA products may play a role in the responses to this toxicant. To study the chemical nature and biological activity of O3-exposed AA, we exposed AA in a cell-free, aqueous environment to air, 0.1 ppm O3, or 1.0 ppm O3 for 30-120 min. AA exposed to air was not degraded. All O3 exposures degraded > 98% of the AA to more polar products, which were predominantly aldehydic substances (as determined by reactivity with 2,4-dinitrophenylhydrazine and subsequent separation by HPLC) andmore » hydrogen peroxide. The type and amount of aldehydic substances formed depended on the O3 concentration and exposure duration. A human bronchial epithelial cell line (BEAS-2B, S6 subclone) exposed in vitro to either 0.1 ppm or 1.0 ppm O3 for 1 hr produced AA-derived aldehydic substances, some of which eluted with similar retention times as the aldehydic substances derived from O3 degradation of AA in the cell-free system. In vitro, O3-degraded AA induced an increase in human peripheral blood polymorphonuclear leukocyte (PMN) polarization, decreased human peripheral blood T-lymphocyte proliferation in response to mitogens, and decreased human peripheral blood natural killer cell lysis of K562 target cells. The aldehydic substances, but not hydrogen peroxide, appeared to be the principal active agents responsible for the observed effects. O3-degraded AA may play a role in the PMN influx into lungs and in decreased T-lymphocyte mitogenesis and natural killer cell activity observed in humans and rodents exposed to O3.« less

The early epigenetic response to ozone: impacts on DNA ...

EPA Pesticide Factsheets

Epigenetics have been increasingly recognized as a mechanism linking environment and gene expression. Despite awareness of the role of DNA methylation and hydroxymethylation as potential drivers of the response to air pollutants, very little work has been performed investigating the direct epigenetic effects following exposure to ambient air pollution. Thus the purpose of this study was to investigate the early epigenetic response to ozone in comparison to the epigenetic modifier 5-aza-2'-deoxycytidine (5-Aza) in rats. 12 week old, male Long-Evans rats (n=16) were exposed to 4 hours of whole-body 1.0 ppm ozone or air and immediately euthanized. A subset of animals were additionally treated with 5-Aza (n=16) to serve as an epigenetic control to ozone exposure. Neither 5-Aza nor ozone by itself induced changes to the global methylome or hydroxmethylome of the lung measured by ELISA. Despite this finding, ozone exposure induced a significant increase in the activity of the DNA methyltransferase enzymes in the lung which was reversed with 5-Aza treatment. Interestingly, a significant interaction between 5-Aza treatment and ozone exposure was found in a large array of data. The interaction between 5-Aza and ozone produced indicators of pulmonary edema and elevated lung damage. Along with these adverse changes, expression of major epigenetic enzymes (Tet 1-3, Dnmt3 a-b) were found to be perturbed in both the lung and hepatic tissues. While ozone exposure appears to in

Interaction of ozone exposure with airway hyperresponsiveness and inflammation induced by trimellitic anhydride in sensitized guinea pigs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Jian; Chung, K.Fan

1997-09-01

The effect of prior ozone (O{sub 3}) exposure on airway hyperresponsiveness and inflammation induced by trimellitic anhydride (TMA) has been investigated in TMA-sensitized guinea pigs. Airway responsiveness was measured as the concentration of acetylcholine needed to increase baseline lung resistance (RL) by 300% (PC300). Ozone (3 ppm, for 3 h) caused an increase in-log PC300 at 1 h after exposure, with return of -log PC300 to control levels at 8 h. Ozone also increased baseline RL at 8 h. TMA challenge increase -log PC300 in TMA-sensitized guinea pigs at 8 h after challenge from 3.85 {+-} 0.09 to 4.11 {+-}more » 0.09. Ozone exposure prior to TMA challenge prevented the induction of airway hyperresponsiveness with a mean -log PC300 of 3.51 {+-} 0.20, which was not different from that of control TMA-Sensitized group. Baseline RL was significantly higher in ozone-pretreated animals after TMA challenge when compared to those of either control or challenged with TMA alone. Ozone had no effect on TMA challenge-induced BAL eosinophilia and neutrophilia. We conclude that a single exposure to ozone inhibits the increase in airway responsiveness, but increases the bronchoconstrictor response induced by TMA in TMA-Sensitized guinea pigs; however, the inflammatory airway response to TMA is unchanged by preexposure to ozone. 29 refs., 2 figs., 1 tab.« less

The effect of antioxidants on ozone-induced airway hyperresponsiveness in dogs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matsui, S.; Jones, G.L.; Woolley, M.J.

1991-12-01

The role of oxygen radicals in causing ozone-induced airway hyperresponsiveness in dogs was examined by pretreating dogs with allopurinol and/or deferoxamine mesylate (desferal), which are inhibitors of oxygen radical generation, before ozone inhalation. Acetylcholine airway responsiveness was measured before and after either air or ozone inhalation (3 ppm for 20 min) on 5 experimental days separated by at least 2 wk. On each day, the dogs were pretreated intravenously with allopurinol (50 mg/kg) followed by inhaled desferal (1,000 mg inhalation) or with allopurinol followed by the diluent for desferal or with the diluent for allopurinol and desferal or with bothmore » diluents. The effect of ozone on acetylcholine airway responsiveness was expressed as the differences in the log-transformed preozone-postozone acetylcholine provocative concentrations. When dogs received both diluents or either treatment alone, ozone inhalation caused airway hyperresponsiveness. The mean log differences for the preozone-postozone acetylcholine provocative concentration were 0.804 (SEM, 0.17) for both diluents, 0.524 (SEM, 0.16) for allopurinol alone, and 0.407 (SEM, 0.22) for desferal alone. However, the combination of allopurinol and desferal significantly inhibited the development of ozone-induced airway hyperresponsiveness, the log difference being 0.195 (SEM, 0.11) (p less than 0.05), without inhibiting ozone-induced neutrophil influx into the airways. The results suggest that the production of oxygen radicals is important in the pathogenesis of ozone-induced airway hyperresponsiveness.« less

Preliminary assessment of heavy metals in water, sediment and macrophyte ( Lemna minor) collected from Anchar Lake, Kashmir, India

NASA Astrophysics Data System (ADS)

Showqi, Irfana; Lone, Farooq Ahmad; Naikoo, Mehrajuddin

2018-06-01

Water samples, sediments and free floating macrophytic plant, Lemna minor specimens were collected from five designated sites in Anchar lake (Srinagar, J&K, India) to assess its heavy metal (Cu, Cr, Zn, Ni, Cd, Pb) load and changes on seasonal basis. The concentration of heavy metals was determined using atomic absorption spectroscopy. Most of the samples were found within limits of maximum permissible concentrations as recommended by WHO (Guidelines for drinking water quality, pp 491-493, 2006). During all the seasons, highest concentration of all heavy metals (Cu, Cr, Zn, Ni, Cd, Pb) was recorded at highly polluted sites of the lake viz. near agricultural fields (S1), near settlements (S3) and SKIMS (S4). These sites received huge agrochemical run-off from the surrounding agricultural fields, solid and liquid wastes from the nearby catchment areas and effluents from Sher-e-Kashmir Institute of Medical Sciences (SKIMS) compared to control site lake centre (S5). Furthermore, most of the metals in water and sediment were found with highest concentration during autumn (Viz., Cu-1.5 ppm; Zn-0.38 ppm; Ni-1.89 ppm; Pb-0.84 ppm in water and Cu-26.9 ppm; Zn-13.6 ppm; Pb-4.33 ppm in sediment) and summer (Viz., Cr-0.68 ppm in water and Ni-4.8 ppm; Cd-2.6 ppm; Cr-8.01 ppm in sediment) seasons. Also in Lemna minor plant highest concentration was observed during summer season (Cu-29.09 ppm; Zn-19.11 ppm; Ni-5.7 ppm; Cd-1.34 ppm; Cr-9.18 ppm and Pb-9.77 ppm). From these observations, it was found that the sources of heavy metals in Anchar lake were both natural and anthropogenic ones. This study recommended that continuous monitoring of heavy metals (Viz; Cu, Cr, Zn, Ni, Cd and Pb) in water, sediment and other aquatic biota of Anchar lake should be directed to protection of ecological status of the lake and its surrounding area.

Recent Greenhouse Gas Concentrations

DOE Data Explorer

Blasing, T. J.

2016-01-01

Gases typically measured in parts per million (ppm), parts per billion (ppb) or parts per trillion (ppt) are presented separately to facilitate comparison of numbers. Global Warming Potentials (GWPs) and atmospheric lifetimes are from the Intergovernmental Panel on Climate Change (IPCC, 2013, Table 8.A.1), except for the atmospheric lifetime of carbon dioxide (CO2) which is explained in footnote 4. Additional material on greenhouse gases can be found in CDIAC's Reference Tools. To find out how CFCs, HFCs, HCFCs, and halons are named, see Name that compound: The numbers game for CFCs, HFCs, HCFCs, and Halons. Concentrations given apply to the lower 75-80 percent of the atmosphere, known as the troposphere. Sources of the current and preindustrial concentrations of the atmospheric gases listed in the table below are given in the footnotes. Investigators at the National Oceanic and Atmospheric Administration have provided the recent concentrations. Much of the data provided results from the work of various investigators at institutions other than CDIAC, and represent considerable effort on their part. We ask as a basic professional courtesy that you acknowledge the primary sources, indicated in the footnotes below, or in the links given in the footnotes. Concentrations of ozone and water vapor are spatially and temporally variable due to their short atmospheric lifetimes. A vertically and horizontally averaged water vapor concentration is about 5,000 ppm. Globally averaged water vapor concentration is difficult to measure precisely because it varies from one place to another and from one season to the next. This precludes a precise determination of changes in water vapor since pre-industrial time. However, a warmer atmosphere will likely contain more water vapor than at present. For a more detailed statement on water vapor from the National Oceanic and Atmospheric Administration, see the "water vapor" page at http://lwf.ncdc.noaa.gov/oa/climate/gases.html

The glutathione-S-transferase mu 1 (GSTM1) null genotype and increased neutrophil response to low-level ozone (0.06 ppm).

EPA Science Inventory

Background: Exposure of healthy young adults to 03 modulates immune cell biology in the airways and causes a significant increase in neutrophilic inflammation which can vary considerably in magnitude across individuals. The GSTM1null genotype modulates Oj-induced inflammation, bu...

Enhanced formation of disinfection byproducts in shale gas wastewater-impacted drinking water supplies.

PubMed

Parker, Kimberly M; Zeng, Teng; Harkness, Jennifer; Vengosh, Avner; Mitch, William A

2014-10-07

The disposal and leaks of hydraulic fracturing wastewater (HFW) to the environment pose human health risks. Since HFW is typically characterized by elevated salinity, concerns have been raised whether the high bromide and iodide in HFW may promote the formation of disinfection byproducts (DBPs) and alter their speciation to more toxic brominated and iodinated analogues. This study evaluated the minimum volume percentage of two Marcellus Shale and one Fayetteville Shale HFWs diluted by fresh water collected from the Ohio and Allegheny Rivers that would generate and/or alter the formation and speciation of DBPs following chlorination, chloramination, and ozonation treatments of the blended solutions. During chlorination, dilutions as low as 0.01% HFW altered the speciation toward formation of brominated and iodinated trihalomethanes (THMs) and brominated haloacetonitriles (HANs), and dilutions as low as 0.03% increased the overall formation of both compound classes. The increase in bromide concentration associated with 0.01-0.03% contribution of Marcellus HFW (a range of 70-200 μg/L for HFW with bromide = 600 mg/L) mimics the increased bromide levels observed in western Pennsylvanian surface waters following the Marcellus Shale gas production boom. Chloramination reduced HAN and regulated THM formation; however, iodinated trihalomethane formation was observed at lower pH. For municipal wastewater-impacted river water, the presence of 0.1% HFW increased the formation of N-nitrosodimethylamine (NDMA) during chloramination, particularly for the high iodide (54 ppm) Fayetteville Shale HFW. Finally, ozonation of 0.01-0.03% HFW-impacted river water resulted in significant increases in bromate formation. The results suggest that total elimination of HFW discharge and/or installation of halide-specific removal techniques in centralized brine treatment facilities may be a better strategy to mitigate impacts on downstream drinking water treatment plants than altering disinfection strategies. The potential formation of multiple DBPs in drinking water utilities in areas of shale gas development requires comprehensive monitoring plans beyond the common regulated DBPs.

Ozone and Botrytis interactions in onion-leaf dieback: open-top chamber studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wukasch, R.T.; Hofstra, G.

1977-09-01

Paired open-top chambers were used to study interactions between Botrytis spp. and ozone in field-grown onions. Charcoal filters removed 35 to 65% of the ambient ozone, resulting in six-fold reduction of onion leaf dieback and a 28% increase in onion yield compared with unfiltered chambers. Symptoms of leaf injury appeared soon after ozone levels exceeded 294 ..mu..g/m/sup 3/ (0.15 ppm) for 4 hr. Lesions caused by Botrytis were few because no dew formed in the chambers. However, when leaves were wetted with foggers, inoculation with mycelial suspensions of B. sauamosa in late August produced significantly more lesions and leaf diebackmore » in the unfiltered chamber. Botrytis squamosa, B. cinerea, B. allii, and several genera of secondary fungi were isolated from these lesions. Botrytis squamosa was recovered from lesions only, whereas B. cinerea and B. allii were associated more generally with onion leaf tissue regardless of lesions. 25 references, 1 figure, 2 tables.« less

Online investigations on ozonation products of pyrene and benz[ a]anthracene particles with a vacuum ultraviolet photoionization aerosol time-of-flight mass spectrometer

NASA Astrophysics Data System (ADS)

Gao, Shaokai; Zhang, Yang; Meng, Junwang; Shu, Jinian

The reaction products of ozone with pyrene and benz[ a]anthracene absorbed on azelaic acid particles under the pseudo-first-order reaction conditions have been investigated with a vacuum ultraviolet photoionization aerosol time-of-flight mass spectrometer (VUV-ATOFMS). The pyrene and benz[ a]anthracene particles with the initial concentrations of ˜1 mg m -3 are respectively exposed to ˜22 ppm ozone in a reaction chamber with a volume of ˜180 L. The time-of-flight mass spectra of the particulate ozonides are obtained. The assignments of the mass spectra reveal that 4-carboxy-5-phenanthrene-carboxyaldehyde (71%) and hydroxypyrene (23%) are the main solid state ozonides of pyrene, while 2-(2-formyl)phenyl-3-naphthoic acid (35%), hydroxybenz[ a]anthrone (30%), and benz[ a]anthracene-7,12-dione (18%) are the main solid state ozonides of benz[ a]anthracene. The pathways of the ozonations are proposed in the paper.

Effects of ozone and nitrogen dioxide on pulmonary function in healthy and in asthmatic adolescents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koenig, J.Q.; Covert, D.S.; Marshall, S.G.

The aim of this project was to investigate whether well-characterized asthmatic adolescent subjects were more sensitive to the inhaled effects of oxidant pollutants than were well-characterized healthy adolescent subjects. Ten healthy and 10 asthmatic subjects inhaled via a mouth-piece 0.12 or 0.18 ppm of ozone (O/sub 3/) or nitrogen dioxide (NO/sub 2/) or clean air for 30 min at rest followed by 10 min during moderate exercise (32.5 L/min) on a treadmill. The following pulmonary functional values were measured before and after exposure: peak flow, total respiratory resistance (RT), maximal flow at 50 and 75% of expired VC, and FEV1.more » After exercise exposure to 0.18 ppm O3, statistically significant increases were seen in RT in asthmatic and healthy adolescent subjects. No consistent changes were seen in either group after NO/sub 2/ exposure. Also, no significant differences in response to oxidant pollutants between the 2 groups could be demonstrated. It was concluded that neither group was consistently sensitive to these pollutants.« less

Efficacy of chlorinated and ozonated water in reducing Salmonella typhimurium attached to tomato surfaces.

PubMed

Chaidez, Cristobal; Lopez, Javier; Vidales, Juan; Campo, Nohelia Castro-Del

2007-08-01

The purpose of this study was to compare chlorinated and ozonated water in reducing Salmonella typhimurium inoculated onto fresh ripe tomatoes. Surface-inoculated tomatoes were immersed/sprayed with chlorinated (200 mg l(-1)) and ozonated water (1 and 2 mg l(-1)) under 2 and 100 nefelometric turbidity units (NTU). Contact times were 120 and 30 s for immersing and spraying applications, respectively. Immersing in chlorinated water and low turbidity resulted in the most effective application with 3.61 log(10) bacterial reduction, while 1 and 2 mg l(-1) of ozone reduced 2.32 and 2.53 log(10), respectively. High turbidity and chlorine reduced the bacterial counts by 3.39 log(10), while 1 and 2 mg l(-1) of ozonated water and low turbidity reduced the bacteria by 1.48 and 1.92 log(10), respectively. Spraying chlorinated water reduced bacteria by 3 log(10), and ozonated water at 1 and 2 mg l(-1) reduced counts by 1.84 and 2.40 log(10), respectively. No statistical differences were found between chlorine and ozone (2 mg l(-1)) during spraying applications (p < 0.05). The use of ozonated water both in immersing and spraying applications is suggested when water turbidity remains low.

Acute Ozone-Induced Pulmonary and Systemic Metabolic Effects Are Diminished in Adrenalectomized Rats

PubMed Central

Miller, Desinia B.; Snow, Samantha J.; Schladweiler, Mette C.; Richards, Judy E.; Ghio, Andrew J.; Ledbetter, Allen D.; Kodavanti, Urmila P.

2016-01-01

Acute ozone exposure increases circulating stress hormones and induces metabolic alterations in animals. We hypothesized that the increase of adrenal-derived stress hormones is necessary for both ozone-induced metabolic effects and lung injury. Male Wistar-Kyoto rats underwent bilateral adrenal demedullation (DEMED), total bilateral adrenalectomy (ADREX), or sham surgery (SHAM). After a 4 day recovery, rats were exposed to air or ozone (1 ppm), 4 h/day for 1 or 2 days and responses assessed immediately postexposure. Circulating adrenaline levels dropped to nearly zero in DEMED and ADREX rats relative to SHAM. Corticosterone tended to be low in DEMED rats and dropped to nearly zero in ADREX rats. Adrenalectomy in air-exposed rats caused modest changes in metabolites and lung toxicity parameters. Ozone-induced hyperglycemia and glucose intolerance were markedly attenuated in DEMED rats with nearly complete reversal in ADREX rats. Ozone increased circulating epinephrine and corticosterone in SHAM but not in DEMED or ADREX rats. Free fatty acids (P = .15) and branched-chain amino acids increased after ozone exposure in SHAM but not in DEMED or ADREX rats. Lung minute volume was not affected by surgery or ozone but ozone-induced labored breathing was less pronounced in ADREX rats. Ozone-induced increases in lung protein leakage and neutrophilic inflammation were markedly reduced in DEMED and ADREX rats (ADREX > DEMED). Ozone-mediated decreases in circulating white blood cells in SHAM were not observed in DEMED and ADREX rats. We demonstrate that ozone-induced peripheral metabolic effects and lung injury/inflammation are mediated through adrenal-derived stress hormones likely via the activation of stress response pathway. PMID:26732886

OZONE BYPRODUCT FORMATION

EPA Science Inventory

The use of ozone for water treatment has been increasing as ozone has great potential for degrading water pollutants and inactivating viruses, Giardia cysts, and Cryptosporidium oocysts. Although it appears that ozone generates less undesirable disinfection by-products (DBPs) th...

Use of fluorescence spectroscopy to control ozone dosage in recirculating aquaculture systems.

PubMed

Spiliotopoulou, Aikaterini; Martin, Richard; Pedersen, Lars-Flemming; Andersen, Henrik R

2017-03-15

The aim of this study was to investigate the potential of fluorescence spectroscopy to be used as an ozone dosage determination tool in recirculating aquaculture systems (RASs), by studying the relationship between fluorescence intensities and dissolved organic matter (DOM) degradation by ozone, in order to optimise ozonation treatment. Water samples from six different Danish facilities (two rearing units from a commercial trout RAS, a commercial eel RAS, a pilot RAS and two marine water aquariums) were treated with different O 3 dosages (1.0-20.0 mg/L ozone) in bench-scale experiments, following which fluorescence intensity degradation was eventually determined. Ozonation kinetic experiments showed that RAS water contains fluorescent organic matter, which is easily oxidised upon ozonation in relatively low concentrations (0-5 mg O 3 /L). Fluorescence spectroscopy has a high level of sensitivity and selectivity in relation to associated fluorophores, and it is able to determine accurately the ozone demand of each system. The findings can potentially be used to design offline or online sensors based on the reduction by ozone of natural fluorescent-dissolved organic matter in RAS. The suggested indirect determination of ozone delivered into water can potentially contribute to a safer and more adequate ozone-based treatment to improve water quality. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fluoride content of infant formulas prepared with deionized, bottled mineral and fluoridated drinking water.

PubMed

Buzalaf, M A; Granjeiro, J M; Damante, C A; de Ornelas, F

2001-01-01

Usually infant milk formula is the major source of fluoride in infancy. Fluoride concentrations in ten samples of powdered milk formulas, prepared with deionized, bottled mineral, and fluoridated drinking water were determined after HMDS-facilitated diffusion, using a fluoride ion specific electrode(Orion 9609). Fluoride concentrations ranged from 0.01 to 0.75 ppm; from 0.02 to 1.37 ppm and from 0.91 to 1.65 ppm for formulas prepared with deionized, bottled mineral (0.02 to 0.69 ppm F) and fluorinated drinking water (0.9 ppm F), respectively. Possible fluoride ingestion per Kg body mass ws estimated. With deionized water, only the soy-based- formulas should provide a daily fluoride intake of above the suggested threshold for fluorosis. With water containing 0.9 ppm F, however, all of them would provide it. Hence, to limit fluoride intakes to amounts <0.1 mg/kg/day, it is necessary to avoid use fo fluoridated water (around 1 ppm) to dilute powdered infant formulas.

Making equipment to process paddy water for providing drinking water by using Ozone-UVC& Ultrafiltration

NASA Astrophysics Data System (ADS)

Styani, E.; Dja'var, N.; Irawan, C.; Hanafi

2018-01-01

This study focuses on making equipment which is useful to process paddy water to be consumable as drinking water by using ozone-UVC and ultrafiltration. The equipment which is made by the process of ozone-UVC and ultrafiltration or reverse osmosis is driven by electric power generated from solar panels. In the experiment, reverse osmosis system with ozone-UVC reactor proves to be good enough in producing high quality drinking water.

Two-dimensional model studies of the effect of supersonic aircraft operations on the stratospheric ozone content

NASA Technical Reports Server (NTRS)

Whitten, R. C.; Borucki, W. J.; Poppoff, I. G.; Latt, L.; Widhopf, G. F.; Capone, L. A.; Reigel, C. A.

1981-01-01

For a fleet of 250 aircraft, the change in the ozone column is predicted to be very close to zero; in fact, the ozone overburden may actually increase as a result of show that above 25 to 30 km the ozone abundance decreases via catalytic destruction, but at lower heights it increases, mainly as a result of coupling with odd hydrogen species. Water vapor released in the engine exhaust is predicted to cause ozone decreases; for the hypothetical engines used in the study, the total column ozone changes due to water vapor emission largely offset the predicted ozone increases due to NOx emission. The actual effect of water vapor may be less than calculated because present models do not include thermal feedback. Feedback refers to the cooling effect of additional water vapor that would tend to slow the NOx reactions which destroy ozone.

Minireview: the health implications of water treatment with ozone.

PubMed

Carmichael, N G; Winder, C; Borges, S H; Backhouse, B L; Lewis, P D

1982-01-11

Ozone is a highly efficient disinfectant which may have significant advantages in water treatment compared to chlorine. It has, however, been shown that mutagenic and possibly carcinogenic byproducts may be produced under certain conditions of ozonation. Light chlorination following ozonization may meet the highest standards of disinfection. In addition the destruction of much of the organic matter by prior ozone treatment may well result in less harmful chlorinated and brominated products in the finished water. In many cases ozone treatment alone may suffice. It would be desirable to test with long term in vivo experiments which of the alternatives produces the best combination of microbiologically clean and pleasant water with minimum mutagenic and carcinogenic effect.

IL-33 Drives Augmented Responses to Ozone in Obese Mice

PubMed Central

Mathews, Joel A.; Krishnamoorthy, Nandini; Kasahara, David Itiro; Cho, Youngji; Wurmbrand, Allison Patricia; Ribeiro, Luiza; Smith, Dirk; Umetsu, Dale; Levy, Bruce D.; Shore, Stephanie Ann

2016-01-01

Background: Ozone increases IL-33 in the lungs, and obesity augments the pulmonary effects of acute ozone exposure. Objectives: We assessed the role of IL-33 in the augmented effects of ozone observed in obese mice. Methods: Lean wildtype and obese db/db mice were pretreated with antibodies blocking the IL-33 receptor, ST2, and then exposed to ozone (2 ppm for 3 hr). Airway responsiveness was assessed, bronchoalveolar lavage (BAL) was performed, and lung cells harvested for flow cytometry 24 hr later. Effects of ozone were also assessed in obese and lean mice deficient in γδ T cells and their wildtype controls. Results and Discussion: Ozone caused greater increases in BAL IL-33, neutrophils, and airway responsiveness in obese than lean mice. Anti-ST2 reduced ozone-induced airway hyperresponsiveness and inflammation in obese mice but had no effect in lean mice. Obesity also augmented ozone-induced increases in BAL CXCL1 and IL-6, and in BAL type 2 cytokines, whereas anti-ST2 treatment reduced these cytokines. In obese mice, ozone increased lung IL-13+ innate lymphoid cells type 2 (ILC2) and IL-13+ γδ T cells. Ozone increased ST2+ γδ T cells, indicating that these cells can be targets of IL-33, and γδ T cell deficiency reduced obesity-related increases in the response to ozone, including increases in type 2 cytokines. Conclusions: Our data indicate that IL-33 contributes to augmented responses to ozone in obese mice. Obesity and ozone also interacted to promote type 2 cytokine production in γδ T cells and ILC2 in the lungs, which may contribute to the observed effects of IL-33. Citation: Mathews JA, Krishnamoorthy N, Kasahara DI, Cho Y, Wurmbrand AP, Ribeiro L, Smith D, Umetsu D, Levy BD, Shore SA. 2017. IL-33 drives augmented responses to ozone in obese mice. Environ Health Perspect 125:246–253; http://dx.doi.org/10.1289/EHP272 PMID:27472835

[Comparative studies on the action of chlorine and ozone on polioviruses in the reprocessing of drinking water in Essen (author's transl)].

PubMed

Thraenhart, O; Kuwert, E

1975-07-01

The present study was performed in order to evaluate comparatively the inactivation of polio virus type I strains (wild type and attenuated) by means of chlorine and ozone. Polio virus type I was chosen with regard to its epidemiological behaviour and high stability in drinking-water and sewage lines. In view of the lack of propagation techniques, hepatitis viruses A and B, unfortunately, could not be used for these experiments. The experiments were done under laboratory conditions only, and not in the water recovery plant because of hygienic reasons. Defined quantities of disinfectants were examined for their virus-inactivating effect in water without redox-potential (double-distilled water), water with low defined redox-potential (double-distilled water + KOH), previously chlorinated water with a residual chlorine content of 0.03 mg chlorine per liter (tap water) and water with a high redox-potential (well water from the drinking-water plant). Time-course studies were performed, both with chlorine and ozone, in order to evaluate the characteristics of the inactivation procedure. The experimental conditions chosen varied from experiment to experiment to obtain relevant conclusions for the practice. On the basis of our results, and taking into account the quantitative differences in effect, chlorine and ozone principially can be considered equivalent in their action of virus-disinfection. Both, the initial rate and the kinetics of virus disinfection are really identical. Both disinfectants are dependant on the condition of the water (redox-potential, pH etc.) to a great extent in their efficacy. Therefore, a decision of whether or not ozone should substitute for chlorine for the drinking-water supply in Essen cannot be drawn on the basis of virological experiments. This decision, then, depends more or less on other questions - such as relative costs and practicability of the ozonization on a large technical scale. The safety risk and technical reliability of the ozonization process is of particular significance. In the present condition of the Essen reservoir water, a good virus disinfection can be expected already with 1.0 to 1.5 mg ozone/liter (dissolved!); such a concentration guarantees very little residual ozone and, thus, makes then this procedure technically feasible. Continuous checking of the redox-potential and the amount of the ozone added is necessary. With regard to a continuous supply of ozone, the dependence on current supply must be guaranteed. Ozonization of water, probably by the cleavage of humic acid, promotes bacterial recontamination of the drinking-water in the city taps(Stalder und Klosterkötter, 45). Therefore only a combined pre-ozonization with subsequent chlorination would guarantee, both, safety and improvement of the cosmetical conditions of the drinking-water. Such a combination would be feasible with highly reduced amounts of ozone and chlorine.

IDENTIFICATION OF BROMOHYDRINS IN OZONATED WATERS

EPA Science Inventory

Because ozonation is becoming a popular alternative to chlorination for disinfection of drinking water and because little is known about the potential adverse effects of ozonation disinfection by-products (DBPs), we have sought to identify ozone DBPs, particularly brominated orga...

Adrenal-derived stress hormones modulate ozone-induced lung injury and inflammation.

PubMed

Henriquez, Andres; House, John; Miller, Desinia B; Snow, Samantha J; Fisher, Anna; Ren, Hongzu; Schladweiler, Mette C; Ledbetter, Allen D; Wright, Fred; Kodavanti, Urmila P

2017-08-15

Ozone-induced systemic effects are modulated through activation of the neuro-hormonal stress response pathway. Adrenal demedullation (DEMED) or bilateral total adrenalectomy (ADREX) inhibits systemic and pulmonary effects of acute ozone exposure. To understand the influence of adrenal-derived stress hormones in mediating ozone-induced lung injury/inflammation, we assessed global gene expression (mRNA sequencing) and selected proteins in lung tissues from male Wistar-Kyoto rats that underwent DEMED, ADREX, or sham surgery (SHAM) prior to their exposure to air or ozone (1ppm), 4h/day for 1 or 2days. Ozone exposure significantly changed the expression of over 2300 genes in lungs of SHAM rats, and these changes were markedly reduced in DEMED and ADREX rats. SHAM surgery but not DEMED or ADREX resulted in activation of multiple ozone-responsive pathways, including glucocorticoid, acute phase response, NRF2, and PI3K-AKT. Predicted targets from sequencing data showed a similarity between transcriptional changes induced by ozone and adrenergic and steroidal modulation of effects in SHAM but not ADREX rats. Ozone-induced increases in lung Il6 in SHAM rats coincided with neutrophilic inflammation, but were diminished in DEMED and ADREX rats. Although ozone exposure in SHAM rats did not significantly alter mRNA expression of Ifnγ and Il-4, the IL-4 protein and ratio of IL-4 to IFNγ (IL-4/IFNγ) proteins increased suggesting a tendency for a Th2 response. This did not occur in ADREX and DEMED rats. We demonstrate that ozone-induced lung injury and neutrophilic inflammation require the presence of circulating epinephrine and corticosterone, which transcriptionally regulates signaling mechanisms involved in this response. Published by Elsevier Inc.

Ozone Therapy Enhances Osseous Healing in Rats With Diabetes With Calvarial Defects: A Morphometric and Immunohistochemical Study.

PubMed

Alpan, Aysan Lektemur; Toker, Hülya; Ozer, Hatice

2016-08-01

Bone healing is impaired in diabetes mellitus (DM) cases. The aim of this study is to investigate, both morphometrically and immunohistochemically, the effect of gaseous ozone on bone healing in diabetic rat calvarial defects treated with xenografts. DM was induced with 50 mg/kg intraperitoneal streptozotocin in 56 male Wistar rats. Study groups were as follows: 1) empty defect (control, n = 14); 2) xenograft (XG, n = 14); 3) empty defect treated with ozone therapy (control + ozone, n = 14); and 4) xenograft and ozone application (XG + ozone, n = 14). Critical-size defects were created in all rats. Bovine-derived xenograft was applied to XG groups. Gaseous ozone was applied on the operation day and daily for 2 weeks (140 ppm at 2 L/d, 2.24 mg). Rats were sacrificed at 4 or 8 weeks post-surgery. Total bone area, newly formed bone, and residual graft material were measured histomorphometrically. Osteocalcin and bone morphogenic protein (BMP)-2 expression was evaluated immunohistochemically. Osteoclast numbers in the XG + ozone group were higher than the other groups at week 4 (P <0.05). XG + ozone group revealed more total bone area and new bone area than the XG group at weeks 4 (P <0.05) and 8 (P >0.05). Residual graft materials were decreased in the XG + ozone group and the same group revealed more BMP-2 positivity compared with other groups. Osteocalcin positivity in XG groups was higher than in control groups. Within the limitations of this DM animal study, gaseous ozone application accelerates xenograft resorption and enhances bone regeneration, especially in the early stages of bone healing.

Indigenous microbes survive in situ ozonation improving biodegradation of dissolved organic matter in aged oil sands process-affected waters.

PubMed

Brown, Lisa D; Pérez-Estrada, Leonidas; Wang, Nan; El-Din, Mohamed Gamal; Martin, Jonathan W; Fedorak, Phillip M; Ulrich, Ania C

2013-11-01

The oil sands industry faces significant challenges in developing effective remediation technologies for process-affected water stored in tailings ponds. Naphthenic acids, a complex mixture of cycloaliphatic carboxylic acids, have been of particular concern because they concentrate in tailings ponds and are a component of the acutely toxic fraction of process water. Ozone treatment has been demonstrated as an effective means of rapidly degrading naphthenic acids, reducing process water toxicity, and increasing its biodegradability following seeding with the endogenous process water bacteria. This study is the first to examine subsequent in situ biodegradation following ozone pretreatment. Two aged oil sands process-affected waters from experimental reclamation tailings ponds were ozonated to reduce the dissolved organic carbon, to which naphthenic acids contributed minimally (<1mgL(-1)). Treatment with an ozone dose of 50mgL(-1) improved the 84d biodegradability of remaining dissolved organic carbon during subsequent aerobic incubation (11-13mgL(-1) removed from aged process-affected waters versus 5mgL(-1) when not pretreated with ozone). The ozone-treated indigenous microbial communities were as capable of degrading organic matter as the same community not exposed to ozone. This supports ozonation coupled with biodegradation as an effective and feasible treatment option. Copyright © 2013 Elsevier Ltd. All rights reserved.

Differential effects of airway anesthesia on ozone-induced pulmonary responses in human subjects.

PubMed

Schelegle, E S; Eldridge, M W; Cross, C E; Walby, W F; Adams, W C

2001-04-01

We examined the effect of tetracaine aerosol inhalation, a local anesthetic, on lung volume decrements, rapid shallow breathing, and subjective symptoms of breathing discomfort induced by the acute inhalation of 0.30 ppm ozone for 65 min in 22 ozone-sensitive healthy human subjects. After 50 min of ozone inhalation FEV(1) was reduced 24%, breathing frequency was increased 40%, tidal volume was decreased 31%, and total subjective symptom score was increased (71.2, compared with 3.8 for filtered air exposure). Inhalation of tetracaine aerosol resulted in marked reductions in ozone-induced subjective symptoms of throat tickle and/or irritation (92.1%), cough (78.5%), shortness of breath (72.5%), and pain on deep inspiration (69.4%). In contrast, inhalation of tetracaine aerosol (mass median aerodynamic diameter of 3.52 microm with a geometric standard deviation of 1.92) resulted in only minor and inconsistent rectification of FEV(1) decrements (5.0%) and breathing frequency (-3.8%) that was not significantly different from that produced by saline aerosol alone (FEV(1), 5.1% and breathing frequency, -2.7%). Our data are consistent with afferent endings located within the large conducting airways of the tracheobronchial tree being primarily responsible for ozone-induced subjective symptoms and provides strong evidence that ozone-induced inhibition of maximal inspiratory effort is not dependent on conscious sensations of inspiratory discomfort.

INFLUENCE OF OZONE EXPOSURE DYNAMICS ON THE GROWTH AND YIELD OF KIDNEY BEAN (JOURNAL VERSION)

EPA Science Inventory

A field experiment was conducted in open-top chambers to assess the importance of peak exposure concentration and exposure frequency on the responses of kidney bean plants to O3. There were five treatments in the study: charcoal-filtered air, constant exposure to 0.05 ppm O3 (131...

Different efficiency of ozonated water washing to inactivate Salmonella enterica typhimurium on green onions, grape tomatoes, and green leaf lettuces.

PubMed

Xu, Wenqing; Wu, Changqing

2014-03-01

Ozonated water washing is one of the emerging techniques to inactivate foodborne pathogens on produce, and limited information is available to optimize processing parameters (treatment time, temperature, and pH) to improve ozone efficacy on Salmonella inactivation for different produce. The efficacy of ozonated water washing for inactivation of Salmonella enterica Typhimurium on green onions, grape tomatoes and green leaf lettuces were studied in our research. Surface inoculated fresh produce were washed by ozonated water for 1, 5, or 10 min at room temperature and pH 5.60 ± 0.03. Then efficacy of ozonated water washing at mild heated (50 °C) and refrigerated (4 °C) temperature for 5 min with pH 5.60 ± 0.03 was investigated. Salmonella inactivation efficacy under pH 5.60 ± 0.03 and 2.64 ± 0.02 with 5 min washing at room temperature were also compared. Our results showed that Salmonella inactivation by ozonated water was time-dependent for 3 fresh produce. Mild heated temperature (50 °C) and pH 2.64 ± 0.02 improved efficacy of ozonated water to inactivate Salmonella on tomatoes and lettuces, but not on green onions. It is suggested that different surface structures of fresh produce significantly impact the antimicrobial efficacy of ozonated water washing operated under various parameters (time, temperature, and pH). Washing is the essential step for green onions and lettuces in the packinghouse and grape tomatoes in the restaurants and grocery stores having salad bars. Ozonated water can be used as disinfectant to reduce microbial contamination (FDA). The effectiveness of this disinfectant depends on the type of product and treatment conditions, such as water temperature, acidity, contact time. Our study showed that Salmonella inactivation by ozonated water washing was time-dependent. Mild heat and low pH improved inactivation efficacy on tomatoes and lettuces, but not on green onions. Processors should consider adjustments that are most appropriate for their produce. © 2014 Institute of Food Technologists®

Effects of conventional ozonation and electro-peroxone pretreatment of surface water on disinfection by-product formation during subsequent chlorination.

PubMed

Mao, Yuqin; Guo, Di; Yao, Weikun; Wang, Xiaomao; Yang, Hongwei; Xie, Yuefeng F; Komarneni, Sridhar; Yu, Gang; Wang, Yujue

2018-03-01

The electro-peroxone (E-peroxone) process is an emerging ozone-based electrochemical advanced oxidation process that combines conventional ozonation with in-situ cathodic hydrogen peroxide (H 2 O 2 ) production for oxidative water treatment. In this study, the effects of the E-peroxone pretreatment on disinfection by-product (DBP) formation from chlorination of a synthetic surface water were investigated and compared to conventional ozonation. Results show that due to the enhanced transformation of ozone (O 3 ) to hydroxyl radicals (OH) by electro-generated H 2 O 2 , the E-peroxone process considerably enhanced dissolved organic carbon (DOC) abatement and significantly reduced bromate (BrO 3 - ) formation compared to conventional ozonation. However, natural organic matter (NOM) with high UV 254 absorbance, which is the major precursors of chlorination DBPs, was less efficiently abated during the E-peroxone process than conventional ozonation. Consequently, while both conventional ozonation and the E-peroxone process substantially reduced the formation of DBPs (trihalomethanes and haloacetic acids) during post-chlorination, higher DBP concentrations were generally observed during chlorination of the E-peroxone pretreated waters than conventional ozonation treated. In addition, because of conventional ozonation or the E-peroxone treatment, DBPs formed during post-chlorination shifted to more brominated species. The overall yields of brominated DBPs exhibited strong correlations with the bromide concentrations in water. Therefore, while the E-peroxone process can effectively suppress bromide transformation to bromate, it may lead to higher formation of brominated DBPs during post-chlorination compared to conventional ozonation. These results suggest that the E-peroxone process can lead to different DBP formation and speciation during water treatment trains compared to conventional ozonation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Structural and functional localization of airway effects from episodic exposure of infant monkeys to allergen and/or ozone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joad, Jesse P.; Kott, Kayleen S.; Bric, John M.

2006-08-01

Both allergen and ozone exposure increase asthma symptoms and airway responsiveness in children. Little is known about how these inhalants may differentially modify airway responsiveness in large proximal as compared to small distal airways. We evaluated whether bronchi and respiratory bronchioles from infant monkeys exposed episodically to allergen and/or ozone differentially develop intrinsic hyperresponsiveness to methacholine and whether eosinophils and/or pulmonary neuroendocrine cells play a role. Infant monkeys were exposed episodically for 5 months to: (1) filtered air, (2) aerosolized house dust mite allergen, (3) ozone 0.5 ppm, or (4) house dust mite allergen + ozone. Studying the function/structure relationshipmore » of the same lung slices, we evaluated methacholine airway responsiveness and histology of bronchi and respiratory bronchioles. In bronchi, intrinsic responsiveness was increased by allergen exposure, an effect reduced by bombesin antagonist. In respiratory bronchioles, intrinsic airway responsiveness was increased by allergen + ozone exposure. Eosinophils were increased by allergen and allergen + ozone exposure in bronchi and by allergen exposure in respiratory bronchioles. In both airways, exposure to allergen + ozone resulted in fewer tissue eosinophils than did allergen exposure alone. In bronchi, but not in respiratory bronchioles, the number of eosinophils and neuroendocrine cells correlated with airway responsiveness. We conclude that episodically exposing infant monkeys to house dust mite allergen with or without ozone increased intrinsic airway responsiveness to methacholine in bronchi differently than in respiratory bronchioles. In bronchi, eosinophils and neuroendocrine cells may play a role in the development of airway hyperresponsiveness.« less

High pre-eruptive water contents preserved in lunar melt inclusions.

PubMed

Hauri, Erik H; Weinreich, Thomas; Saal, Alberto E; Rutherford, Malcolm C; Van Orman, James A

2011-07-08

The Moon has long been thought to be highly depleted in volatiles such as water, and indeed published direct measurements of water in lunar volcanic glasses have never exceeded 50 parts per million (ppm). Here, we report in situ measurements of water in lunar melt inclusions; these samples of primitive lunar magma, by virtue of being trapped within olivine crystals before volcanic eruption, did not experience posteruptive degassing. The lunar melt inclusions contain 615 to 1410 ppm water and high correlated amounts of fluorine (50 to 78 ppm), sulfur (612 to 877 ppm), and chlorine (1.5 to 3.0 ppm). These volatile contents are very similar to primitive terrestrial mid-ocean ridge basalts and indicate that some parts of the lunar interior contain as much water as Earth's upper mantle.

Application of ozonation for pharmaceuticals and personal care products removal from water.

PubMed

Gomes, João; Costa, Raquel; Quinta-Ferreira, Rosa M; Martins, Rui C

2017-05-15

Due to the shortening on natural water resources, reclaimed wastewater will be an important water supply source. However, suitable technologies must be available to guaranty its proper detoxification with special concern for the emerging pharmaceutical and personal care products that are continuously reaching municipal wastewater treatment plants. While conventional biological systems are not suitable to remove these compounds, ozone, due to its interesting features involving molecular ozone oxidation and the possibility of generating unselective hydroxyl radicals, has a wider range of action on micropollutants removal and water disinfection. This paper aims to review the studies dealing with ozone based processes for water reuse by considering municipal wastewater reclamation as well as natural and drinking water treatment. A comparison with alternative technologies is given. The main drawback of ozonation is related with the low mineralization achieved that may lead to the production of reaction intermediates with toxic features. The use of hydrogen peroxide and light aided systems enhance ozone action over pollutants. Moreover, scientific community is focused on the development of solid catalysts able to improve the mineralization level achieved by ozone. Special interest is now being given to solar light catalytic ozonation systems with interesting results both for chemical and biological contaminants abatement. Nowadays the integration between ozonation and sand biofiltration seems to be the most interesting cost effective methodology for water treatment. However, further studies must be performed to optimize this system by understanding the biofiltration mechanisms. Copyright © 2017 Elsevier B.V. All rights reserved.

Ozone susceptibility of selected woody shrubs and vines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, D.D.; Coppolino, J.B.

1976-10-01

Thirteen species of woody shrubs and vines were exposed to 0.25 ppm ozone for 8 hours at biweekly intervals throughout the 1975 growing season. A different set of plants was utilized in each biweekly exposure. The most susceptible species was staghorn sumac (Rhus typhina), followed in descending order of susceptibility by Virginia creeper (Parthenocissus quinquefolia), Indian currant (coral berry) (Symphoricarpus orbiculatus), American elder (Sambucus canadensis), dwarf ninebark (Physocarpus opulifolius), multiflora rose (Rosa multiflora), smooth sumac (Rhus glabra), redosier dogwood (Cornus stolonifera), silky dogwood (Cornus amomum), autumn olive (Elaeagnus angustifolia), white snowberry (Symphoricarpus albus), bittersweet (Celastrus scandens), and Morrow honeysuckle (Loniceramore » morrowi). The latter three species were very resistant. The most common symptom induced by ozone was a dark pigmented stipple on the upper leaf surface. The foliage of all species became increasingly resistant toward the end of the growing season.« less

Process Performances of 2 ns Pulsed Discharge Plasma

NASA Astrophysics Data System (ADS)

Matsumoto, Takao; Wang, Douyan; Namihira, Takao; Akiyama, Hidenori

2011-08-01

Pulsed discharge plasmas have been used to treat exhaust gases. Since pulse duration and the rise time of applied voltage to the discharge electrode has a strong influence on the energy efficiency of pollutant removal, the development of a short-pulse generator is of paramount importance for practical applications. In this work, it is demonstrated that the non thermal plasma produced by the 2 ns pulsed discharge has a higher energy efficiency than the 5 ns pulsed discharge plasma for NO removal and ozone generation. Typically, the NO removal efficiency was 1.0 mol kW-1 h-1 for 70% NO removal (initial NO concentration = 200 ppm, gas flow = 10 L/min). Meanwhile, the ozone yield was 500 g kW-1 h-1 for 20 g/m3 ozone concentration in the case of oxygen feeding. These energy efficiencies are the highest in the literature.

Effects of drinking water monochloramine on lipid and thyroid metabolism in healthy men.

PubMed Central

Wones, R G; Deck, C C; Stadler, B; Roark, S; Hogg, E; Frohman, L A

1993-01-01

The purpose of this study was to determine whether a 4-week consumption of 1.5L per day of drinking water containing monochloramine at a concentration of 2 ppm (ppm = mg/L) or 15 ppm under controlled conditions would alter parameters of lipid or thyroid metabolism in healthy men. Forty-eight men completed an 8-week protocol during which diet (600 mg cholesterol per day, 40% calories as fat) and other factors known to affect lipid metabolism were controlled. During the first 4 weeks of the protocol, all subjects consumed distilled water. During the second 4 weeks, one-third of the subjects were assigned randomly to drink 1.5 L per day of water containing 2 ppm of monochloramine, to drink 1.5 L per day of water containing 15 ppm monochloramine, or to continue drinking distilled water. Four blood samples were collected from each subject at the end of each 4-week study period. Subjects drinking monochloramine at a concentration of 2 ppm showed no significant changes in total cholesterol, triglycerides, HDL cholesterol, LDL cholesterol, apolipoproteins A1, A2, or B when compared to the distilled water group. Parameters of thyroid function also were unchanged by exposure to monochloramine at this concentration. However, subjects drinking monochloramine at a concentration of 15 ppm experienced an increase in the level of apolipoprotein B. Other parameters of lipid and thyroid metabolism did not change. We conclude that consumption of drinking water containing 2 ppm of monochloramine does not alter parameters of lipid and thyroid metabolism in healthy men. Consumption of water containing 15 ppm monochloramine may be associated with increased levels of plasma apolipoprotein B. PMID:8319653

Pulmonary inflammation induced by subacute ozone is augmented in adiponectin deficient mice: role of IL-17A

PubMed Central

Kasahara, David I.; Kim, Hye Y.; Williams, Alison S.; Verbout, Norah G.; Tran, Jennifer; Si, Huiqing; Wurmbrand, Allison P.; Jastrab, Jordan; Hug, Christopher; Umetsu, Dale T.; Shore, Stephanie A.

2012-01-01

Pulmonary responses to ozone, a common air pollutant, are augmented in obese individuals. Adiponectin, an adipose derived hormone that declines in obesity, has regulatory effects on the immune system. To determine the role of adiponectin in the pulmonary inflammation induced by extended (48–72 h) low dose (0.3 ppm) exposure to ozone, adiponectin deficient (Adipo−/−) and wildtype mice were exposed to ozone or to room air. In wildtype mice, ozone exposure increased total bronchoalveolar lavage (BAL) adiponectin. Ozone induced lung inflammation, including increases in BAL neutrophils, protein (an index of lung injury), IL-6, KC, LIX and G-CSF were augmented in Adipo−/− versus wildtype mice. Ozone also increased IL-17A mRNA expression to a greater extent in Adipo−/− versus wildtype mice. Moreover, compared to control antibody, anti-IL-17A antibody attenuated ozone-induced increases in BAL neutrophils and G-CSF in Adipo−/− but not in wildtype mice, suggesting that IL-17A, by promoting G-CSF release, contributed to augmented neutrophilia in Adipo−/− mice. Flow-cytometric analysis of lung cells revealed that the number of CD45+/F4/80+/IL-17A+ macrophages and γδ T cells expressing IL-17A increased after ozone exposure in wildtype mice, and further increased in Adipo−/− mice. The IL-17+ macrophages were CD11c− (interstitial macrophages), whereas CD11c+ macrophages (alveolar macrophages) did not express IL-17A. Taken together, the data are consistent with the hypothesis that adiponectin protects against neutrophil recruitment induced by extended, low dose ozone exposure by inhibiting the induction and/or recruitment of IL-17A in interstitial macrophages and/or γδ T cells. PMID:22474022

Ozone and allergen exposure during postnatal development alters the frequency and airway distribution of CD25+ cells in infant rhesus monkeys

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Lisa A.; California National Primate Research Center, University of California, Davis, CA 95616; Gerriets, Joan E.

2009-04-01

The epidemiologic link between air pollutant exposure and asthma has been supported by experimental findings, but the mechanisms are not understood. In this study, we evaluated the impact of combined ozone and house dust mite (HDM) exposure on the immunophenotype of peripheral blood and airway lymphocytes from rhesus macaque monkeys during the postnatal period of development. Starting at 30 days of age, monkeys were exposed to 11 cycles of filtered air, ozone, HDM aerosol, or ozone + HDM aerosol. Each cycle consisted of ozone delivered at 0.5 ppm for 5 days (8 h/day), followed by 9 days of filtered air;more » animals received HDM aerosol during the last 3 days of each ozone exposure period. Between 2-3 months of age, animals co-exposed to ozone + HDM exhibited a decline in total circulating leukocyte numbers and increased total circulating lymphocyte frequency. At 3 months of age, blood CD4+/CD25+ lymphocytes were increased with ozone + HDM. At 6 months of age, CD4+/CD25+ and CD8+/CD25+ lymphocyte populations increased in both blood and lavage of ozone + HDM animals. Overall volume of CD25+ cells within airway mucosa increased with HDM exposure. Ozone did not have an additive effect on volume of mucosal CD25+ cells in HDM-exposed animals, but did alter the anatomical distribution of this cell type throughout the proximal and distal airways. We conclude that a window of postnatal development is sensitive to air pollutant and allergen exposure, resulting in immunomodulation of peripheral blood and airway lymphocyte frequency and trafficking.« less

Heavy metals and hydrocarbon concentrations in water, sediments and tissue of Cyclope neritea from two sites in Suez Canal, Egypt and histopathological effects.

PubMed

Sharaf, Hesham M; Shehata, Abdalla M

2015-01-01

Heavy metals and hydrocarbons are of the most common marine pollutants around the world. The present study aimed to assess the concentration of petroleum hydrocarbons and heavy metals in tissues of the snail cyclope neritea, water and sediments from two sites of the study area (Temsah lake and Suez canal) represent polluted and unpolluted sites respectively. The results showed that, the levels of the heavy metals (Pb, Cd, Co, Mg and Zn) in the polluted area have reached harmful limits recorded globally. Lead in water, sediment and tissue of the snail reached to 0.95 ppm, 4.54 ppm and 7.93 ppm respectively. Cadmium reached 0.31 ppm, 1.15 ppm and 3.08 ppm in the corresponding samples. Cobalt was not detected in water, but it reached 1.42 ppm and 10.36 ppm in the sediment and snails tissue respectively. Magnesium in water, sediment and tissue of the snail reached 3.73 ppm, 9.44 ppm and12.6 ppm respectively. Zinc reached 0.11 ppm, 3.89 ppm and 12.60ppm in the corresponding samples. Meanwhile, hydrocarbons in the polluted area (site1) reached 110.10 μg/L, 980.15 μg/g and 228.00 μg/g in water sediment and digestive gland tissues of the snails respectively. Whereas, hydrocarbons in the unpolluted area (site2) were estimated as 14.20 μg/L, 55.60 μg/g and 22.66 μg/g in water, sediment and tissue of the snails respectively. The combination of histopathological image with monitoring of the metal level in the digestive gland of the present snail provides an important tool for early detection of impending environmental problems and potential public health issues. Petroleum hydrocarbons are toxic to the marine fauna when present above certain limit in the marine water. The major detoxification organ in molluscs is the digestive gland, which has been used as a bioindicator organ for toxicity assessment. The effect of high crude oil on the digestive gland tubules of exposed snails when examined microscopically reveals a series of histological changes which indicates that the cellular compensatory mechanism is activated by hydrocarbons. These changes include vacuolation and presence of pyknotic nuclei.

20-HETE mediates ozone-induced, neutrophil-independent airway hyper-responsiveness in mice.

PubMed

Cooper, Philip R; Mesaros, A Clementina; Zhang, Jie; Christmas, Peter; Stark, Christopher M; Douaidy, Karim; Mittelman, Michael A; Soberman, Roy J; Blair, Ian A; Panettieri, Reynold A

2010-04-20

Ozone, a pollutant known to induce airway hyper-responsiveness (AHR), increases morbidity and mortality in patients with obstructive airway diseases and asthma. We postulate oxidized lipids mediate in vivo ozone-induced AHR in murine airways. Male BALB/c mice were exposed to ozone (3 or 6 ppm) or filtered air (controls) for 2 h. Precision cut lung slices (PCLS; 250 microm thickness) containing an intrapulmonary airway ( approximately 0.01 mm(2) lumen area) were prepared immediately after exposure or 16 h later. After 24 h, airways were contracted to carbachol (CCh). Log EC(50) and E(max) values were then calculated by measuring the airway lumen area with respect to baseline. In parallel studies, dexamethasone (2.5 mg/kg), or 1-aminobenzotriazol (ABT) (50 mg/kg) were given intraperitoneal injection to naïve mice 18 h prior to ozone exposure. Indomethacin (10 mg/kg) was administered 2 h prior. Cell counts, cytokine levels and liquid chromatography-mass spectrometry (LC-MS) for lipid analysis were assessed in bronchoalveolar lavage (BAL) fluid from ozone exposed and control mice. Ozone acutely induced AHR to CCh. Dexamethasone or indomethacin had little effect on the ozone-induced AHR; while, ABT, a cytochrome P450 inhibitor, markedly attenuated airway sensitivity. BAL fluid from ozone exposed animals, which did not contain an increase in neutrophils or interleukin (IL)-6 levels, increased airway sensitivity following in vitro incubation with a naïve PCLS. In parallel, significant increases in oxidized lipids were also identified using LC-MS with increases of 20-HETE that were decreased following ABT treatment. These data show that ozone acutely induces AHR to CCh independent of inflammation and is insensitive to steroid treatment or cyclooxygenase (COX) inhibition. BAL fluid from ozone exposed mice mimicked the effects of in vivo ozone exposure that were associated with marked increases in oxidized lipids. 20-HETE plays a pivotal role in mediating acute ozone-induced AHR.

Health assessment for Liquid Gold-Richmond, Richmond, Contra Costa County, California, Region 9. CERCLIS No. CAT000646208. Preliminary report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The Liquid Gold-Richmond site is on the National Priorities List. The site consists of approximately 18 acres of a 29-acre property currently owned by Southern Pacific Transportation, which is located partially on and adjacent to tidal marsh areas and the San Francisco Bay. The environmental contamination (maximum concentrations reported) on-site consists of lead (280 ppm), zinc (510 ppm), and phenols (18 ppm) in surface soil; lead (3,650 ppm), chromium (50 ppm), nickel (97 ppm), and zinc (3,300 ppm) in subsurface soil; and lead (16 ppm), nickel (1.6 ppm), chromium (2.4 ppm), and zinc (24 ppm) in ground water. The sitemore » is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substances via contaminated ground water. In addition, off-site migration of surface migration of surface water, soil, and sediment could adversely impact the fish and shellfish areas adjacent to the site.« less

Role of ozone and granular activated carbon in the removal of mutagenic compounds.

PubMed Central

Bourbigot, M M; Hascoet, M C; Levi, Y; Erb, F; Pommery, N

1986-01-01

The identification of certain organic compounds in drinking water has led water treatment specialists to be increasingly concerned about the eventual risks of such pollutants to the health of consumers. Our experiments focused on the role of ozone and granular activated carbon in removing mutagenic compounds and precursors that become toxic after chlorination. We found that if a sufficient dose of ozone is applied, its use does not lead to the creation of mutagenic compounds in drinking water and can even eliminate the initial mutagenicity of the water. The formation of new mutagenic compounds seems to be induced by ozonation that is too weak, although these mutagens can be removed by GAC filtration. Ozone used with activated carbon can be one of the best means for eliminating the compounds contributing to the mutagenicity of water. A combined treatment of ozone and activated carbon also decreases the chlorine consumption of the treated water and consequently reduces the formation of chlorinated organic compounds. PMID:3816720

Lithium Cell Reactions.

DTIC Science & Technology

1983-12-01

Li/SOCL, cells in- dicate that up to PPM water can be added to the electrolyte without detrimental effects. At water levels ab 100 PPM voltage delay...48 2.3 THE EFFECT OF WATER AND HYDROLYSIS PRODUCTS ON PERFORMANCE ........ 51 2.4 THE...Li/SOCI, Cells with 0, 20 and 100 PPM Water added to the Electrolyte.* ..................................................... 52 51. Voltage Delay for

Catalytic ozonation of dimethyl phthalate and chlorination disinfection by-product precursors over Ru/AC.

PubMed

Wang, Jianbing; Zhou, Yunrui; Zhu, Wanpeng; He, Xuwen

2009-07-15

Catalytic ozonation of dimethyl phthalate (DMP) in aqueous solution (5mg/L) under various reactions was performed to examine the effect of catalyst dosage, catalyst particle size, ozone dosage, and gas flow rate on the mineralization of DMP. The mineralization of DMP can be achieved via ozonation and the presence of Ru/AC could greatly accelerate the mineralization rate of DMP in ozonation process. In the continuous experiment of the Ru/AC catalyzed ozonation of DMP, total organic carbon (TOC) removals were kept stable around 75% during 42 h reaction. No leaching of ruthenium was observed in the treated water samples. The treatment of natural water using Ru/AC+O(3), Ru/AC+O(2) and ozonation alone was studied. In the Ru/AC+O(3) process, TOC removals, the reductions of the haloacetic acid formation potentials (HAAFPs), and the reductions of the trihalomethane formation potentials (THMFPs) of 11 water samples were 22-44%, 39-61% and 50-65%, respectively. Ru/AC+O(3) process was much more effective than ozonation alone for TOC removal and the reduction of disinfection by-product formation potential (DBPFP) in the treatment of natural water. It is a promising water treatment technology.

Distribution of trace gases and aerosols in the Siberian air shed during wildfires of summer 2012

NASA Astrophysics Data System (ADS)

Belan, Boris D.; Paris, Jean-Daiel; Nedelec, Philippe; Antokhin, Pavel N.; Arshinova, Victoriya; Arshinov, Mikhail Yu.; Belan, Sergey B.; Davydov, Denis K.; Ivlev, Georgii A.; Fofonov, Alexandre V.; Kozlov, Artem V.; Rasskazchikova, Tatyana M.; Savkin, Denis E.; Simonenkov, Denis V.; Sklyadneva, Tatyana K.; Tolmachev, Gennadii N.

2017-04-01

During the last two decades, three strong biomass burning events have been observed in Russia: two of them in 2002 and 2010 in the European part of Russia, and another one in 2012 in West and East Siberia. In this paper we present results of the extensive airborne study of the vertical distribution of trace gases and aerosols carried out during strong wildfire event happened in summer 2012 in Siberia. For this purpose, the Optik TU-134 aircraft laboratory was used as a research platform. A large-scale airborne campaign has been undertaken along the route Novosibirsk-Mirny-Yakutsk-Bratsk-Novosibirsk on 31st of July and 1st of August, 2012. Flight pattern consisted of a number of ascents and descents between close to the ground and 8 km altitude that enabled 20 vertical profiles to be obtained. Campaign was conducted under the weather conditions of low-gradient baric field that determined the low speed transport of air masses, as well as the accumulation of biomass burning emissions in the region under study. Highest concentrations of CO2, CH4 and CO over wildfire spots reached 432 ppm, 2367 ppb, and 4036 ppb, correspondingly. If we exclude from the analysis the data obtained when crossing smoke plumes, we can find a difference between background concentrations measured in the atmosphere over regions affected by biomass burning and clean areas. Enhancement of CO2 over the wildfire areas changed with altitude. On average, it was 10.5 ppm in the atmospheric boundary layer (ABL) and 5-6 ppm in the free troposphere. Maximum CO2 enhancements reached 27 ppm and 24 ppm, correspondingly. The averaged CH4 enhancement varied from 75 ppb in the boundary layer to 30 ppb in the upper troposphere, and a little bit lower than 30 ppb in the middle troposphere. Maximum CH4 enhancements reached 202 ppb, 108 ppb, and 50-60 ppb, correspondingly. The averaged and maximum enhancements of CO differed by an order of magnitude. Thus, in the ABL the maximum difference in concentration between clean and wildfire areas reached 2300 ppb, while averaged one was 170 ppb. In the middle troposphere maximum enhancements varied from 1000 to 1700 ppb. The vertical distribution of ozone has its own peculiarities. Ozone concentration decreased in the layers with enhanced aerosol concentration and it increased in the areas with lower aerosol content. At the same time, photochemical production ozone was observed at the plume edges in the zone of fresh air entrainment. This work was supported by the Russian Foundation for Basic Research (grant No 17-05-00374).

Changes in concentrations of triazine and acetamide herbicides by bank filtration, ozonation, and chlorination in a public water supply

USGS Publications Warehouse

Verstraeten, Ingrid M.; Thurman, E.M.; Lindsey, M.E.; Lee, E.C.; Smith, R.D.

2002-01-01

The changes in triazine and acetamide concentrations in water during natural and artificial treatment by bank filtration, ozonation, filtration, and chlorination were measured at the well field and drinking water treatment plant of Lincoln, Nebraska, USA. The city's groundwater supply is affected by induced infiltration and transport of triazines and acetamide herbicides from the Platte River in late spring and early summer. The objective of the study was to evaluate the effect of infiltration and treatment on the presence of triazines and acetamides in drinking water. Samples of river water, well water, and public supply water at various stages of water treatment were collected from 1997-1999 during spring-runoff when the presence of herbicides in the Platte River is largest. In 1999, parent compounds were reduced by 76% of the concentration present in river water (33% by bank filtration, 41% by ozonation, and 1.5% by chlorination). Metabolites of herbicides for which analytical techniques existed were reduced by 21% (plus 26% by bank filtration, minus 23% by ozonation, and minus 24% by chlorination). However, increases in concentrations of specific metabolite compounds were identified after bank filtration and ozonation. After bank filtration, increases in cyanazine amide, cyanazine acid, and deethylcyanazine acid were identified. After ozonation, concentrations of deisopropylatrazine, deethylatrazine, didealkylatrazine, atrazine amide-I, hydroxydeethylatrazine, hydroxydeisopopylatrazine, deethylcyanazine acid, and deethylcyanazine increased. Concentrations of cyanazine acid and ethanesulfonic and oxanilic acids of acetamides decreased during ozonation. Our findings suggest that bank filtration and ozonation of water in part can shift the assessment of risk to human health associated with the consumption of the water from the parent compounds to their degradation products.

Foliar injury response of petunia and kidney bean to simultaneous and alternate exposures to ozone and pan

NASA Astrophysics Data System (ADS)

Nouchi, Isamu; Mayumi, Hirokazu; Yamazoe, Fumio

Petunia at about 6 weeks old and kidney bean at two growing stages (6-7 days old and 16-18 days old) were exposed separately to O 3, (0-0.40 ppm) and PAN (0-0.25 ppm) for 4 h and to the mixture for the same time. In addition, petunia was exposed to O, (0.10-0.40 ppm) and then PAN (0.010-0.040 ppm) for 4 h, respectively. Foliar injury of petunia and kidney bean in exposures to the mixtures of O 3 and PAN was significantly smaller than that induced by each oxidant, with the exception of PAN injury on young leaves of 16-18 day-old kidney bean. The percentage of foliar injury caused by either of the mixed pollutants decreased with an increase of the concentration of the other oxidant, and was found to approximate a logarithmic function of the combined pollutant concentrations expressed as O 3, minum PAN or vice versa. Alternate exposures caused no additive or synergistic injuries.

A Review of Microbubble and its Applications in Ozonation

NASA Astrophysics Data System (ADS)

Shangguan, Yufei; Yu, Shuili; Gong, Chao; Wang, Yue; Yang, Wangzhen; Hou, Li-an

2018-03-01

Ozonation has been demonstrated to be an effective technology for the oxidation of organic matters in water treatment. But the low solubility and low mass transfer efficiency limit the application. Microbubble technology has the potential of enhancing gas-liquid mass transfer efficiency, thus it can be applied in ozonation process. The applications of microbubble ozonation have shown advantages over macro bubble ozonation in mass transfer and reaction rate. Microbubble ozonation will be a promising treatment both in water and wastewater treatment.

Solar or UVA-Visible Photocatalytic Ozonation of Water Contaminants.

PubMed

Beltrán, Fernando J; Rey, Ana

2017-07-14

An incipient advanced oxidation process, solar photocatalytic ozonation (SPO), is reviewed in this paper with the aim of clarifying the importance of this process as a more sustainable water technology to remove priority or emerging contaminants from water. The synergism between ozonation and photocatalytic oxidation is well known to increase the oxidation rate of water contaminants, but this has mainly been studied in photocatalytic ozonation systems with lamps of different radiation wavelength, especially of ultraviolet nature (UVC, UVB, UVA). Nowadays, process sustainability is critical in environmental technologies including water treatment and reuse; the application of SPO systems falls into this category, and contributes to saving energy and water. In this review, we summarized works published on photocatalytic ozonation where the radiation source is the Sun or simulated solar light, specifically, lamps emitting radiation to cover the UVA and visible light spectra. The main aspects of the review include photoreactors used and radiation sources applied, synthesis and characterization of catalysts applied, influence of main process variables (ozone, catalyst, and pollutant concentrations, light intensity), type of water, biodegradability and ecotoxicity, mechanism and kinetics, and finally catalyst activity and stability.

76 FR 47443 - Approval and Promulgation of State Implementation Plans; State of Colorado; Attainment...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-05

... ozone concentrations is less than or equal to 0.08 ppm. Forty CFR part 50, Appendix I, section 2.3... at both locations. This is 0.2 ppb lower than Colorado's 2008 modeling projected using incorrect..., section 2.1, page 15; section 3.0, pages 20-28; section 4.2, page 40.) Colorado followed this procedure in...

Response of the macaque nasal epithelium to ambient levels of ozone. A morphologic and morphometric study of the transitional and respiratory epithelium.

PubMed Central

Harkema, J. R.; Plopper, C. G.; Hyde, D. M.; St George, J. A.; Wilson, D. W.; Dungworth, D. L.

1987-01-01

Although ozone (O3)-induced bronchiolitis has been morphologically characterized, effects of O3 on the upper respiratory tract have not been thoroughly investigated. The purpose of this study was to determine whether exposures to ambient levels of O3 induce lesions in the nasal mucosa. Bonnet monkeys were exposed to 0.00, 0.15, or 0.30 ppm O3 for 6 or 90 days, 8 hours/day. After exposure, nasal mucosa was processed for light and electron microscopy. Quantitative changes were evident in the nasal transitional and respiratory epithelium. At 6 or 90 days of exposure to 0.15 or 0.30 ppm O3 lesions consisted of ciliated cell necrosis, shortened cilia, and secretory cell hyperplasia. Inflammatory cell influx was only present at 6 days of exposure. Ultrastructural changes in goblet cells were evident at 90 days. Ambient levels of O3 can induce significant nasal epithelial lesions, which may compromise upper respiratory defense mechanisms. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:3605312

Validating a High Performance Liquid Chromatography-Ion Chromatography (HPLC-IC) Method with Conductivity Detection After Chemical Suppression for Water Fluoride Estimation.

PubMed

Bondu, Joseph Dian; Selvakumar, R; Fleming, Jude Joseph

2018-01-01

A variety of methods, including the Ion Selective Electrode (ISE), have been used for estimation of fluoride levels in drinking water. But as these methods suffer many drawbacks, the newer method of IC has replaced many of these methods. The study aimed at (1) validating IC for estimation of fluoride levels in drinking water and (2) to assess drinking water fluoride levels of villages in and around Vellore district using IC. Forty nine paired drinking water samples were measured using ISE and IC method (Metrohm). Water samples from 165 randomly selected villages in and around Vellore district were collected for fluoride estimation over 1 year. Standardization of IC method showed good within run precision, linearity and coefficient of variance with correlation coefficient R 2  = 0.998. The limit of detection was 0.027 ppm and limit of quantification was 0.083 ppm. Among 165 villages, 46.1% of the villages recorded water fluoride levels >1.00 ppm from which 19.4% had levels ranging from 1 to 1.5 ppm, 10.9% had recorded levels 1.5-2 ppm and about 12.7% had levels of 2.0-3.0 ppm. Three percent of villages had more than 3.0 ppm fluoride in the water tested. Most (44.42%) of these villages belonged to Jolarpet taluk with moderate to high (0.86-3.56 ppm) water fluoride levels. Ion Chromatography method has been validated and is therefore a reliable method in assessment of fluoride levels in the drinking water. While the residents of Jolarpet taluk (Vellore distict) are found to be at a high risk of developing dental and skeletal fluorosis.

Degradation of 2,4-dichlorophenol using combined approach based on ultrasound, ozone and catalyst.

PubMed

Barik, Arati J; Gogate, Parag R

2017-05-01

The present work investigates the application of ultrasound and ozone operated individually and in combination with catalyst (ZnO and CuO) for establishing the possible synergistic effects for the degradation of 2,4-dichlorophenol. The dependency of extent of degradation on the operating parameters like temperature (over the range of 30-36°C), initial pH (3-9), catalyst as ZnO (loading of 0.025-0.15g/L) and CuO (loading of 0.02-0.1g/L) and initial concentration of 2,4-DCP (20-50ppm) has been established to maximize the efficacy of ultrasound (US) induced degradation. Using only US, the maximum degradation of 2,4-DCP obtained was 28.85% under optimized conditions of initial concentration as 20ppm, pH of 5 and temperature of 34°C. Study of effect of ozone flow rate for approach of only ozone revealed that maximum degradation was obtained at 400mg/h ozone flow rate. The combined approaches such as US+O 3 , US+ZnO, US+CuO, O 3 +ZnO, O 3 +CuO, US+O 3 +ZnO and US+O 3 +CuO have been subsequently investigated under optimized conditions and observed to be more efficient as compared to individual approaches. The maximum extent of degradation for the combined operation of US+O 3 (400mg/h)+ZnO (0.1g/L) and US+O 3 (400mg/h)+CuO (0.08g/L) has been obtained as 95.66% and 97.03% respectively. The degradation products of 2,4-DCP have been identified using GC-MS analysis and the toxicity analysis has also been performed based on the anti-microbial activity test (agar-well diffusion method) for the different treatment strategies. The present work has conclusively established that the combined approach of US+O 3 +CuO was the most efficient treatment scheme resulting in near complete degradation of 2,4-DCP with production of less toxic intermediates. Copyright © 2016 Elsevier B.V. All rights reserved.

The effect of selenium on spoil suitability as root zone material at Navajo Mine, New Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lane, J.R.; Buchanan, B.A.; Ramsey, T.C.

1995-09-01

The root zone suitability limits for spoil Se at Navajo Mine in northwest New Mexico are currently 0.8 ppm total Se and 0.15 ppm hot-water soluble Se. These criteria were largely developed by the Office of Surface Mining using data from the Northern Great Plains. Applying these values, approximately 23% of the spoil volume and 47% of the spoil area sampled at Navajo Mine from 1985 to December 1993 were determined to be unsuitable as root zone material. Secondary Se accumulator plants (Atriplex canescens) growing in both undisturbed and reclaimed areas were randomly sampled for selenium from 1985 to Decembermore » 1993. In most cases the undisturbed soil and reclaimed spoil at these plant sampling sites were sampled for both total and hot-water soluble Se. Selenium values for Atriplex canescens samples collected on the undisturbed sites averaged 0.64 ppm and ranged from 0.20 ppm to 2.5 ppm. Selenium values for the plants growing on spoil ranged from 0.02 ppm to 7.75 ppm and averaged 1.07 ppm. Total and hot-water Se values for spoil averaged 0.66 ppm and 0.06 ppm respectively, and ranged from 0.0 to 14.2 for total Se and 0.0 ppm to 0.72 ppm for hot-water soluble Se. The plant Se values were poorly correlated to both total and hot-water soluble Se values for both soil and spoil. Therefore, predicting suitable guidelines using normal regression techniques was ineffective. Based on background Se levels in native soils, and levels found on reclaimed areas with Atriplex canescens, it is suggested that a total Se level of 2.0 ppm and a hot-water soluble Se level of 0.25 ppm should be used to represent the suitability limits for Se at Navajo Mine. If these Se values are used, it is estimated that less than 1% of the spoil volume would be unsuitable. This volume of spoil seems to be a more accurate estimate of the amount of spoil with unsuitable levels of Se than the estimated 23% using the current guidelines.« less

Photoenhanced degradation of veratraldehyde upon the heterogeneous ozone reactions.

PubMed

Net, Sopheak; Gligorovski, Sasho; Pietri, Sylvia; Wortham, Henri

2010-07-21

Light-induced heterogeneous reactions between gas-phase ozone and veratraldehyde adsorbed on silica particles were performed. At an ozone mixing ratio of 250 ppb, the loss of veratraldehyde largely increased from 1.81 x 10(-6) s(-1) in the dark to 2.54 x 10(-5) s(-1) upon exposure to simulated sunlight (lambda > 300 nm). The observed rates of degradation exhibited linear dependence with the ozone in the dark ozonolysis experiments which change in the non-linear Langmuir-Hinshelwood dependence in the experiments with simultaneous ozone and light exposure of the coated particles. When the coated silica particles were exposed only to simulated sunlight in absence of ozone the loss of veratraldehyde was about three times higher i.e. 5.97 x 10(-6) s(-1) in comparison to the ozonolysis experiment under dark conditions at 250 ppb ozone mixing ratio, 1.81 x 10(-6) s(-1).These results clearly show that the most important loss of veratraldehyde occurs under simultaneous ozone and light exposure of the coated silica particles. The main identified product in the heterogeneous reactions between gaseous ozone and adsorbed veratraldehyde under dark conditions and in presence of light was veratric acid.Carbon yields of veratric acid were calculated and the obtained results indicated that at low ozone mixing ratio (250 ppb) the carbon yield obtained under dark conditions is 70% whereas the carbon yield obtained in the experiments with simultaneous ozone and light exposure of the coated particles is 40%. In both cases the carbon yield of veratric acid exponentially decayed leading to the plateau ( approximately 35% of carbon yield) at an ozone mixing ratio of 6 ppm. Two reaction products i.e. 3-hydroxy-4-methoxybenzoic acid and 4-hydroxy-3-methoxybenzoic acid were identified (confirmed with the standards) only in the experiments performed under simultaneous ozonolysis and light irradiation of the particles.

Geology and ground-water resources of Nobles County, and part of Jackson County, Minnesota

USGS Publications Warehouse

Norvitch, Ralph F.

1964-01-01

The quality of water in the Precambrian crystalline rocks, the Cretaceous strata, and the buried Pleistocene aquifers is poor. Chemical analyses of 22 water samples showed that dissolved solids ranged from 1,100 ppm (parts per million) to 3,050 ppm. Water from the surficial outwash deposits is good by comparison; dissolved solids in water from these aquifers ranged from 425 to 870 ppm.

ADVANCED OXIDATION PROCESS TECHNOLOGY (ULTRAVIOLET RADIATION/OZONE TREATMENT) FOR REMOVAL OF METHYL TERTIARY BUTYL ETHER (MTBE) IN GROUND WATER SUPPLIES.

EPA Science Inventory

U.S. EPA’s Office of Research and Development in Cincinnati, Ohio has been testing and evaluating MTBE removal in dechlorinated tap water using three oxidant combinations: hydrogen peroxide/ozone, ultraviolet irradiation (UV)/ozone, and UV/ozone/hydrogen peroxide. Pilot-scale st...

Ozone treatment and the depletion of detectable pharmaceuticals and atrazine herbicide in drinking water sourced from the upper Detroit River, Ontario, Canada.

PubMed

Hua, Wenyi; Bennett, Erin R; Letcher, Robert J

2006-07-01

The depletion and degradation of pharmacologically active compounds (PhACs) and pesticides as a function of ozonation in drinking water treatment processes is not well studied. The A.H. Weeks drinking water treatment plant (DWTP) serves the City of Windsor, Ontario Canada, and incorporates ozone treatment into the production of drinking water. This DWTP also operates a real-time, scaled down pilot plant, which has two parallel streams, conventional and ozone plus conventional treatments. In this study water samples were collected from key points in the two streams of the pilot plant system to determine the depletion and influence of seasonal changes in water processing parameters on eighteen major PhACs (and metabolites) and seven s-triazines herbicides. However, only carbamazepine (antiepileptic), caffeine (stimulant), cotinine (metabolite of nicotine) and atrazine were consistently detectable in the raw water intake (low to sub-ng/L level). Regardless of the seasonality, the flocculation-coagulation and dual media filtration steps without ozone treatment resulted in no decrease in analyte concentrations, while decreases of 66-100% (undetectable, method detection limits 0.05-1 ng/L) of the analyte concentrations were observed when ozone treatment was part of the water processing. These findings demonstrate that ozone treatment is highly effective in depleting carbamazepine, caffeine, cotinine, and atrazine, and thus is highly influential in the fate of these compounds in drinking water treatment regardless of the seasonal time frame. Currently very few Canadian DWTPs incorporate ozonation into conventional treatment, which suggests that human exposure to these compounds via drinking water consumption may be an issue in affected communities.

Maternal diesel inhalation increases airway hyperreactivity in ozone-exposed offspring.

PubMed

Auten, Richard L; Gilmour, M Ian; Krantz, Q Todd; Potts, Erin N; Mason, S Nicholas; Foster, W Michael

2012-04-01

Air pollutant exposure is linked with childhood asthma incidence and exacerbations, and maternal exposure to airborne pollutants during pregnancy increases airway hyperreactivity (AHR) in offspring. To determine if exposure to diesel exhaust (DE) during pregnancy worsened postnatal ozone-induced AHR, timed pregnant C57BL/6 mice were exposed to DE (0.5 or 2.0 mg/m(3)) 4 hours daily from Gestation Day 9-17, or received twice-weekly oropharyngeal aspirations of the collected DE particles (DEPs). Placentas and fetal lungs were harvested on Gestation Day 18 for cytokine analysis. In other litters, pups born to dams exposed to air or DE, or to dams treated with aspirated diesel particles, were exposed to filtered air or 1 ppm ozone beginning the day after birth, for 3 hours per day, 3 days per week for 4 weeks. Additional pups were monitored after a 4-week recovery period. Diesel inhalation or aspiration during pregnancy increased levels of placental and fetal lung cytokines. There were no significant effects on airway leukocytes, but prenatal diesel augmented ozone-induced elevations of bronchoalveolar lavage cytokines at 4 weeks. Mice born to the high-concentration diesel-exposed dams had worse ozone-induced AHR, which persisted in the 4-week recovery animals. Prenatal diesel exposure combined with postnatal ozone exposure also worsened secondary alveolar crest development. We conclude that maternal inhalation of DE in pregnancy provokes a fetal inflammatory response that, combined with postnatal ozone exposure, impairs alveolar development, and causes a more severe and long-lasting AHR to ozone exposure.

Ozone-Induced Injury and Oxidative Stress in Bronchiolar Epithelium Are Associated with Altered Pulmonary Mechanics

PubMed Central

Sunil, Vasanthi R.

2013-01-01

In these studies, we analyzed the effects of ozone on bronchiolar epithelium. Exposure of rats to ozone (2 ppm, 3h) resulted in rapid (within 3h) and persistent (up to 72h) histological changes in the bronchiolar epithelium, including hypercellularity, loss of cilia, and necrotizing bronchiolitis. Perivascular edema and vascular congestion were also evident, along with a decrease in Clara cell secretory protein in bronchoalveolar lavage, which was maximal 24h post-exposure. Ozone also induced the appearance of 8-hydroxy-2′-deoxyguanosine, Ym1, and heme oxygenase-1 in the bronchiolar epithelium. This was associated with increased expression of cleaved caspase-9 and beclin-1, indicating initiation of apoptosis and autophagy. A rapid and persistent increase in galectin-3, a regulator of epithelial cell apoptosis, was also observed. Following ozone exposure (3–24h), increased expression of cyclooxygenase-2, inducible nitric oxide synthase, and arginase-1 was noted in bronchiolar epithelium. Ozone-induced injury and oxidative stress in bronchiolar epithelium were linked to methacholine-induced alterations in pulmonary mechanics. Thus, significant increases in lung resistance and elastance, along with decreases in lung compliance and end tidal volume, were observed at higher doses of methacholine. This indicates that ozone causes an increase in effective stiffness of the lung as a consequence of changes in the conducting airways. Collectively, these studies demonstrate that bronchiolar epithelium is highly susceptible to injury and oxidative stress induced by acute exposure to ozone; moreover, this is accompanied by altered lung functioning. PMID:23492811

Generation and delivery device for ozone gas and ozone dissolved in water

NASA Technical Reports Server (NTRS)

Andrews, Craig C. (Inventor); Murphy, Oliver J. (Inventor)

2006-01-01

The present invention provides an ozone generation and delivery system that lends itself to small scale applications and requires very low maintenance. The system includes an anode reservoir and a cathode phase separator each having a hydrophobic membrane to allow phase separation of produced gases from water. The system may be configured to operate passively with no moving parts or in a self-pressurizing manner with the inclusion of a pressure controlling device or valve in the gas outlet of the anode reservoir. The hydrogen gas, ozone gas and water containing ozone may be delivered under pressure.

Generation and delivery device for ozone gas and ozone dissolved in water

NASA Technical Reports Server (NTRS)

Andrews, Craig C. (Inventor); Rogers, Thomas D. (Inventor); Murphy, Oliver J. (Inventor)

1999-01-01

The present invention provides an ozone generation and delivery system that lends itself to small scale applications and requires very low maintenance. The system includes an anode reservoir and a cathode phase separator each having a hydrophobic membrane to allow phase separation of produced gases from water. The system may be configured to operate passively with no moving parts or in a self-pressurizing manner with the inclusion of a pressure controlling device or valve in the gas outlet of the anode reservoir. The hydrogen gas, ozone gas and water containing ozone may be delivered under pressure.

Effect of ozonation on minocycline degradation and N-Nitrosodimethylamine formation.

PubMed

Lv, Juan; Li, Yong M

2018-06-07

The objective of this study was to assess reactivity of Minocycline (MNC) towards ozone and determine the effects of ozone dose, pH value, and water matrix on MNC degradation as well as to characterize N-Nitrosodimethylamine (NDMA) formation from MNC ozonation. The MNC initial concentration of the solution was set in the range of 2-20 mg/L to investigate NDMA formation during MNC ozonation. Four ozone doses (22.5, 37.2, 58.0, and 74.4 mg/min) were tested to study the effect of ozone dose. For the evaluation of effects of pH value, pH was adjusted from 5 to 9 in the presence of phosphate buffer. MNC ozonation experiments were also conducted in natural water to assess the influence of water matirx. The influence of the typical component of natural water was also investigated with the addition of HA and NaHCO 3 solution. Results indicated that ozone was effective in MNC removal. Consequently, NDMA and dimethylamine (DMA) were generated from MNC oxidation. Increasing pH value enhanced MNC removal but led to greater NDMA generation. Water matrices, such as HCO 3 - and humic acid, affected MNC degradation. Conversely, more NDMA accumulated due to the inhibition of NDMA oxidation by oxidant consumption. Though ⋅OH can enhance MNC degradation, ozone molecules were heavily involved in NDMA production. Seven transformation products were identified. However, only DMA and the unidentified tertiary amine containing DMA group contributed to NDMA formation.

Water Reclamation Using a Ceramic Nanofiltration Membrane and Surface Flushing with Ozonated Water

PubMed Central

Hoang, Anh T.; Okuda, Tetsuji; Takeuchi, Haruka; Tanaka, Hiroaki; Nghiem, Long D.

2018-01-01

A new membrane fouling control technique using ozonated water flushing was evaluated for direct nanofiltration (NF) of secondary wastewater effluent using a ceramic NF membrane. Experiments were conducted at a permeate flux of 44 L/m2h to evaluate the ozonated water flushing technique for fouling mitigation. Surface flushing with clean water did not effectively remove foulants from the NF membrane. In contrast, surface flushing with ozonated water (4 mg/L dissolved ozone) could effectively remove most foulants to restore the membrane permeability. This surface flushing technique using ozonated water was able to limit the progression of fouling to 35% in transmembrane pressure increase over five filtration cycles. Results from this study also heighten the need for further development of ceramic NF membrane to ensure adequate removal of pharmaceuticals and personal care products (PPCPs) for water recycling applications. The ceramic NF membrane used in this study showed approximately 40% TOC rejection, and the rejection of PPCPs was generally low and highly variable. It is expected that the fouling mitigation technique developed here is even more important for ceramic NF membranes with smaller pore size and thus better PPCP rejection. PMID:29671797

Water Reclamation Using a Ceramic Nanofiltration Membrane and Surface Flushing with Ozonated Water.

PubMed

Fujioka, Takahiro; Hoang, Anh T; Okuda, Tetsuji; Takeuchi, Haruka; Tanaka, Hiroaki; Nghiem, Long D

2018-04-19

A new membrane fouling control technique using ozonated water flushing was evaluated for direct nanofiltration (NF) of secondary wastewater effluent using a ceramic NF membrane. Experiments were conducted at a permeate flux of 44 L/m²h to evaluate the ozonated water flushing technique for fouling mitigation. Surface flushing with clean water did not effectively remove foulants from the NF membrane. In contrast, surface flushing with ozonated water (4 mg/L dissolved ozone) could effectively remove most foulants to restore the membrane permeability. This surface flushing technique using ozonated water was able to limit the progression of fouling to 35% in transmembrane pressure increase over five filtration cycles. Results from this study also heighten the need for further development of ceramic NF membrane to ensure adequate removal of pharmaceuticals and personal care products (PPCPs) for water recycling applications. The ceramic NF membrane used in this study showed approximately 40% TOC rejection, and the rejection of PPCPs was generally low and highly variable. It is expected that the fouling mitigation technique developed here is even more important for ceramic NF membranes with smaller pore size and thus better PPCP rejection.

Disinfection of model indicator organisms in a drinking water pilot plant by using PEROXONE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wolfe, R.L.; Stewart, M.H.; Liang, S.

PEROXONE is an advanced oxidation process generated by combining ozone and hydrogen peroxide. This process stimulates the production of hydroxyl radicals, which have been shown to be superior to ozone for the destruction of some organic contaminants. In this study, pilot-scale experiments were conducted to evaluate the microbicidal effectiveness of PEROXONE and ozone against three model indicator groups. Escherichia coli and MS2 coliphage were seeded into the influent to the preozonation contactors of a pilot plant simulating conventional water treatment and were exposed to four ozone dosages, four hydrogen peroxide/ozone weight ratios, and four contact times in two source waters--Coloradomore » River water and state project water--of different quality. The removal of heterotrophic plate count bacteria was also monitored. Results of the study indicated that the microbicidal activity of PEROXONE was greatly affected by the applied ozone dose, H2O2/O3 ratio, contact time, source water quality, and type of microorganism tested. At contact times of 5 min or less, ozone alone was a more potent bactericide than PEROXONE at all H2O2/O3 ratios tested. However, this decrease in the bactericidal potency of PEROXONE was dramatic only as the H2O2/O3 ratio was increased from 0.5 to 0.8. The fact that the bactericidal activity of PEROXONE generally decreased with increasing H2O2/O3 ratios was thought to be related to the lower ozone residuals produced. The viricidal activity of PEROXONE and ozone was comparable at all of the H2O2/O3 ratios. Heterotrophic plate count bacteria were the most resistant group of organisms. Greater inactivation of E. coli and MS2 was observed in Colorado River water than in state project water and appeared to result from differences in the turbidity and alkalinity of the two waters. Regardless of source water, greater than 4.5 log10 of E.« less

Geology and ground-water resources of Winkler County, Texas

USGS Publications Warehouse

Garza, Sergio; Wesselman, John B.

1963-01-01

The chemical quality of the water in the principal aquifers is generally acceptable for industry and for public supply. About two-thirds of the samples collected from fresh-water wells had a dissolved-solids content of less than 1,000 ppm (parts per million) ; however, some samples in a few areas were hard and were high in fluoride and silica. Samples from wells in polluted areas contained dissolved solids ranging from about 1,400 to 71,100 ppm. Two comprehensive analyses of water samples from the Rustler formation showed a dissolved-solids content of 18,400 ppm. and 157,000 ppm. In most of the water produced with the oil in the Hendrick oil field, the content of dissolved solids ranged from about 4,000 to about 10,000 ppm. The water produced with the oil in the rest of the oil fields in Winkler County was mainly brine.

Impact of ozonation and biological activated carbon filtration on ceramic membrane fouling.

PubMed

Ibn Abdul Hamid, Khaled; Sanciolo, Peter; Gray, Stephen; Duke, Mikel; Muthukumaran, Shobha

2017-12-01

Ozone pre-treatment (ozonation, ozonisation) and biological activated carbon (BAC) filtration pre-treatment for the ceramic microfiltration (CMF) treatment of secondary effluent (SE) were studied. Ozone pre-treatment was found to result in higher overall removal of UV absorbance (UVA 254 ) and colour, and higher permeability than BAC pre-treatment or the combined use of ozone and BAC (O3+BAC) pre-treatment. The overall removal of colour and UVA 254 by ceramic filtration of the ozone pre-treated water was 97% and 63% respectively, compared to 86% and 48% respectively for BAC pre-treatment and 29% and 6% respectively for the untreated water. Ozone pre-treatment, however, was not effective in removal of dissolved organic carbon (DOC). The permeability of the ozone pre-treated water through the ceramic membrane was found to decrease to 50% of the original value after 200 min of operation, compared to approximately 10% of the original value for the BAC pre-treated, O3+BAC pre-treated water and the untreated water. The higher permeability of the ozone pre-treated water was attributed to the excellent removal of biopolymer particles (100%) and high removal of humic substances (84%). The inclusion of a BAC stage between ozone pre-treatment and ceramic filtration was detrimental. The O3+BAC+CMF process was found to yield higher biopolymer removal (96%), lower humic substance (HS) component removal (66%) and lower normalized permeability (0.1) after 200 min of operation than the O3+CMF process (86%, 84% and 0.5 respectively). This was tentatively attributed to the chemical oxidation effect of ozone on the BAC biofilm and adsorbed components, leading to the generation of foulants that are not generated in the O3+CMF process. This study demonstrated the potential of ozone pre-treatment for reducing organic fouling and thus improving flux for the CMF of SE compared to O3+BAC pre-treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Growth of soybean at future tropospheric ozone concentrations decreases canopy evapotranspiration and soil water depletion.

PubMed

Bernacchi, Carl J; Leakey, Andrew D B; Kimball, Bruce A; Ort, Donald R

2011-06-01

Tropospheric ozone is increasing in many agricultural regions resulting in decreased stomatal conductance and overall biomass of sensitive crop species. These physiological effects of ozone forecast changes in evapotranspiration and thus in the terrestrial hydrological cycle, particularly in intercontinental interiors. Soybean plots were fumigated with ozone to achieve concentrations above ambient levels over five growing seasons in open-air field conditions. Mean season increases in ozone concentrations ([O₃]) varied between growing seasons from 22 to 37% above background concentrations. The objective of this experiment was to examine the effects of future [O₃] on crop ecosystem energy fluxes and water use. Elevated [O₃] caused decreases in canopy evapotranspiration resulting in decreased water use by as much as 15% in high ozone years and decreased soil water removal. In addition, ozone treatment resulted in increased sensible heat flux in all years indicative of day-time increase in canopy temperature of up to 0.7 °C. Published by Elsevier Ltd.

Coordinated profiling of stratospheric intrusions and transported pollution by the Tropospheric Ozone Lidar Network (TOLNet) and NASA Alpha Jet experiment (AJAX): Observations and comparison to HYSPLIT, RAQMS, and FLEXPART

NASA Astrophysics Data System (ADS)

Langford, A. O.; Alvarez, R. J.; Brioude, J.; Evan, S.; Iraci, L. T.; Kirgis, G.; Kuang, S.; Leblanc, T.; Newchurch, M. J.; Pierce, R. B.; Senff, C. J.; Yates, E. L.

2018-02-01

Ground-based lidars and ozonesondes belonging to the NASA-supported Tropospheric Ozone Lidar Network (TOLNet) are used in conjunction with the NASA Alpha Jet Atmospheric eXperiment (AJAX) to investigate the transport of stratospheric ozone and entrained pollution into the lower troposphere above the United States on May 24-25, 2013. TOLNet and AJAX measurements made in California, Nevada, and Alabama are compared to tropospheric ozone retrievals from the Atmospheric Infrared Sounder (AIRS), to back trajectories from the NOAA Air Resources Laboratory (ARL) Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model, and to analyses from the NOAA/NESDIS Real-time Air Quality Modeling System (RAQMS) and FLEXPART particle dispersion model. The measurements and model analyses show much deeper descent of ozone-rich upper tropospheric/lower stratospheric air above the Desert Southwest than above the Southeast, and comparisons to surface measurements from regulatory monitors reporting to the U.S. EPA Air Quality System (AQS) suggest that there was a much greater surface impact in the Southwest including exceedances of the 2008 National Ambient Air Quality Standard (NAAQS) of 0.075 ppm in both Southern California and Nevada. Our analysis demonstrates the potential benefits to be gained by supplementing the existing surface ozone network with coordinated upper air observations by TOLNet.

Aerosolized neutral endopeptidase reverses ozone-induced airway hyperreactivity to substance P.

PubMed

Murlas, C G; Lang, Z; Williams, G J; Chodimella, V

1992-03-01

We investigated the effects of ozone exposure (3.0 ppm, 2 h) on airway neutral endopeptidase (NEP) activity and bronchial reactivity to substance P in guinea pigs. Reactivity after ozone or air exposure was determined by measuring specific airway resistance in intact unanesthetized spontaneously breathing animals in response to increasing doses of intravenous substance P boluses. The effective dose of substance P (in micrograms) that produced a doubling of baseline specific airway resistance (ED200SP) was determined by interpolation of cumulative substance P dose-response curves. NEP activity was measured in tracheal homogenates made from each animal of other groups exposed to either ozone or room air. By reverse-phase high-pressure liquid chromatography, this activity was characterized by the phosphoramidon-inhibitable cleavage of alanine-p-nitroaniline from succinyl-(Ala)3-p-nitroaniline in the presence of 100 microM amastatin. Mean values of the changes in log ED200SP were 0.27 +/- 0.07 (SE) for the ozone-exposed group and 0.08 +/- 0.04 for the air-exposed group. We found that phosphoramidon significantly increased substance P reactivity in the air-exposed animals (P less than 0.01), but it had no effect in the ozone-exposed group. This finding was associated with a significant reduction in tracheal homogenate NEP activity of ozone-exposed animals compared with controls: mean values were 18.1 +/- 1.9 nmol.min-1.mg protein-1 for the ozone-exposed group and 25.1 +/- 2.4 nmol.min-1.mg protein-1 for air-exposed animals (P less than 0.05). Inhalation of an aerosolized NEP preparation, partially purified from guinea pig kidney, reversed the substance P hyperreactivity produced by ozone exposure.(ABSTRACT TRUNCATED AT 250 WORDS)

Aerosolized neutral endopeptidase reverses ozone-induced airway hyperreactivity to substance P

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murlas, C.G.; Lang, Z.; Williams, G.J.

1992-03-01

The authors investigated the effects of ozone exposure (3.0 ppm, 2 h) on airway neutral endopeptidase (NEP) activity and bronchial reactivity to substance P in guinea pigs. Reactivity after ozone or air exposure was determined by measuring specific airway resistance in intact unanesthetized spontaneously breathing animals in response to increasing doses of intravenous substance P boluses. The effective dose of substance P (in micrograms) that produced a doubling of baseline specific airway resistance (ED200SP) was determined by interpolation of cumulative substance P dose-response curves. NEP activity was measured in tracheal homogenates made from each animal of other groups exposed tomore » either ozone or room air. By reverse-phase high-pressure liquid chromatography, this activity was characterized by the phosphoramidon-inhibitable cleavage of alanine-p-nitroaniline from succinyl-(Ala)3-p-nitroaniline in the presence of 100 microM amastatin. Mean values of the changes in log ED200SP were 0.27 +/- 0.07 (SE) for the ozone-exposed group and 0.08 +/- 0.04 for the air-exposed group. We found that phosphoramidon significantly increased substance P reactivity in the air-exposed animals (P less than 0.01), but it had no effect in the ozone-exposed group. This finding was associated with a significant reduction in tracheal homogenate NEP activity of ozone-exposed animals compared with controls: mean values were 18.1 +/- 1.9 nmol.min-1.mg protein-1 for the ozone-exposed group and 25.1 +/- 2.4 nmol.min-1.mg protein-1 for air-exposed animals (P less than 0.05). Inhalation of an aerosolized NEP preparation, partially purified from guinea pig kidney, reversed the substance P hyperreactivity produced by ozone exposure.(ABSTRACT TRUNCATED AT 250 WORDS)« less

Ozone oxidation of pharmaceuticals, endocrine disruptors and pesticides during drinking water treatment.

PubMed

Broséus, R; Vincent, S; Aboulfadl, K; Daneshvar, A; Sauvé, S; Barbeau, B; Prévost, M

2009-10-01

This study investigates the oxidation of pharmaceuticals, endocrine disrupting compounds and pesticides during ozonation applied in drinking water treatment. In the first step, second-order rate constants for the reactions of selected compounds with molecular ozone (k(O3)) were determined in bench-scale experiments at pH 8.10: caffeine (650+/-22M(-1)s(-1)), progesterone (601+/-9M(-1)s(-1)), medroxyprogesterone (558+/-9M(-1)s(-1)), norethindrone (2215+/-76M(-1)s(-1)) and levonorgestrel (1427+/-62M(-1)s(-1)). Compared to phenolic estrogens (estrone, 17beta-estradiol, estriol and 17alpha-ethinylestradiol), the selected progestogen endocrine disruptors reacted far slower with ozone. In the second part of the study, bench-scale experiments were conducted with surface waters spiked with 16 target compounds to assess their oxidative removal using ozone and determine if bench-scale results would accurately predict full-scale removal data. Overall, the data provided evidence that ozone is effective for removing trace organic contaminants from water with ozone doses typically applied in drinking water treatment. Ozonation removed over 80% of caffeine, pharmaceuticals and endocrine disruptors within the CT value of about 2 mg min L(-1). As expected, pesticides were found to be the most recalcitrant compounds to oxidize. Caffeine can be used as an indicator compound to gauge the efficacy of ozone treatment.

3D Flower-like β-MnO2/Reduced Graphene Oxide Nanocomposites for Catalytic Ozonation of Dichloroacetic Acid

NASA Astrophysics Data System (ADS)

Li, Gang; Li, Kezheng; Liu, Aijuan; Yang, Ping; Du, Yukou; Zhu, Mingshan

2017-03-01

Considering the potential use of manganese oxide based nanocomposite in catalytic ozonation of water contaminant, we report unique three-dimensional (3D) nanoarchitectures composed of β-MnO2 and reduced graphene oxide (RGO) for catalytic ozonation of dichloroacetic acid (DCAA) from drinking water. The catalytic results show that the 3D β-MnO2/RGO nanocomposites (FMOG) can be used as efficient and stable ozonation catalysts to eliminate DCAA from water. The probable mechanism of catalytic ozonation was also proposed by detecting intermediates using gas chromatography-mass spectrometry. This result likely paves a facile avenue and initiates new opportunities for the exploration of heterogeneous catalysts for the removal of disinfection by-products from drinking water.

Improvement of a respiratory ozone analyzer.

PubMed

Ultman, J S; Ben-Jebria, A; Mac Dougall, C S; Rigas, M L

1997-10-01

The breath-to-breath measurement of total respiratory ozone (O3) uptake requires monitoring O3 concentration at the airway opening with an instrument that responds rapidly relative to the breathing frequency. Our original chemiluminescent analyzer, using 2-methyl-2-butene as the reactant gas, had a 10% to 90% step-response time of 110 msec and a minimal detectable concentration of 0.018 parts per million (ppm) O3 (Ben-Jebria et al. 1990). This instrument was suitable for respiratory O3 monitoring during quiet breathing and light exercise. For this study, we constructed a more self-contained analyzer with a faster response time using ethylene as the reactant gas. When the analyzer was operated at a reaction chamber pressure of 350 torr, an ethylene-to-sample flow ratio of 4:1, and a sampling flow of 0.6 liters per minute (Lpm), it had a 10% to 90% step-response time of 70 msec and a minimal detectable concentration of 0.006 ppm. These specifications make respiratory O3 monitoring possible during moderate-to-heavy exercise. In addition, the nonlinear calibration and the carbon dioxide (CO2) interference exhibited by the original analyzer were eliminated. In breath-to-breath measurements in two healthy men, the fractional uptake of O3 during one minute of quiet breathing was comparable to the results obtained by using a slowly responding commercial analyzer with a quasi-steady material balance method (Wiester et al. 1996). In fact, fractional uptake was about 0.8 regardless of O3 exposure concentration (0.11 to 0.43 ppm) or ventilation rate (4 to 41 Lpm/m2).

75 FR 2938 - National Ambient Air Quality Standards for Ozone

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-19

...Based on its reconsideration of the primary and secondary national ambient air quality standards (NAAQS) for ozone (O3) set in March 2008, EPA proposes to set different primary and secondary standards than those set in 2008 to provide requisite protection of public health and welfare, respectively. With regard to the primary standard for O3, EPA proposes that the level of the 8-hour primary standard, which was set at 0.075 ppm in the 2008 final rule, should instead be set at a lower level within the range of 0.060 to 0.070 parts per million (ppm), to provide increased protection for children and other ``at risk'' populations against an array of O3-related adverse health effects that range from decreased lung function and increased respiratory symptoms to serious indicators of respiratory morbidity including emergency department visits and hospital admissions for respiratory causes, and possibly cardiovascular-related morbidity as well as total non-accidental and cardiopulmonary mortality. With regard to the secondary standard for O3, EPA proposes that the secondary O3 standard, which was set identical to the revised primary standard in the 2008 final rule, should instead be a new cumulative, seasonal standard expressed as an annual index of the sum of weighted hourly concentrations, cumulated over 12 hours per day (8 am to 8 pm) during the consecutive 3-month period within the O3 season with the maximum index value, set at a level within the range of 7 to 15 ppm- hours, to provide increased protection against O3-related adverse impacts on vegetation and forested ecosystems.

[Effect of ozonated water on physical and chemical properties of vacuum sealing drainage material].

PubMed

Jiang, Nan; Ma, Yunfei; Lin, Qingrong; Chen, Anfu; Zhao, Peiran; Ni, Guoxin; Yu, Bin

2013-02-01

To investigate the influence of ozonated water on physical and chemical properties of vacuum sealing drainage (VSD) materials. VSD materials (foam and sealing membrane) were immersed in 10 µg/ml ozonated water for 1 h twice daily for 8 days. The foam appearance and microscopic structure of the materials were observed, and tensile tests and Raman spectrum scan were performed assess the effect of ozonated water. Simulated VSD devices were prepared and tested for leakproofness under negative pressure after ozonated water treatment. zonated water treatment for 8 days caused no obvious abnormal changes in the foam appearance or microscopic structure of the materials. The maximum tensile load of foam before and after ozonated water treatment was 4.25∓0.73 kgf and 2.44∓0.19 kgf (P=0.000), the momentary distance when the foam torn before and after intervention was 92.54∓12.83 mm and 64.44∓4.60 mm, respectively (P=0.000). The corresponding results for VSD sealing membrane were 0.70∓0.58 kgf and 0.71∓0.08 kgf (P=0.698), and 99.30∓10.27 mm and 100.95∓18.22 mm (P=0.966), respectively. Raman spectroscopy revealed changes in only several wave intensities and no new chemical groups appeared within the scan range of 400-4000 cm(-1). The VSD device was well hermetic after treatment with ozonated water. Except for a decreased stretch resistance property of the foam, VSD materials display no obvious changes in physical and chemical characteristics after treatment with ozonated water for 8 days.

Ozone and sulfur dioxide effects on tall fescue. I. Growth and yield responses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Flagler, R.B.; Youngner, V.B.

The effects of ozone (O/sub 3/) and sulfur dioxide (SO/sub 2/) on growth and yield components of tall fescue (Festuca arundinacea Schreb. 'Alta') were studied in a greenhouse experiment. Four O/sub 3/ treatments ranging from 0 to 0.30 ppm in equally spaced intervals and two SO/sub 2/ treatments, 0 and 0.10 ppm, were arranged factorially in a randomized complete block design utilizing three blocks. Each block was exposed to the pollutants 6 h/d, once a week, for 12 weeks. Statistical analysis was by analysis of variance and regression techniques. Ozone significantly affected root/shoot ratio and all dry weight fractions. Tillermore » weight was also affected adversely by O/sub 3/ with a linear decrease of >44% at the highest O/sub 3/ level. SO/sub 2/ also affected tall fescue, but not nearly as severely as O/sub 3/. Total dry weight was reduced by 7.3% due to SO/sub 2/. Root weight was decreased by 11%, but shoot weight was unaffected. Root/shoot ratio was lowered about 7% due to the pollutant. Weight per tiller was unaffected by SO/sub 2/. Number of tillers was significantly reduced by an interaction of the two pollutants. Neither O/sub 3/ or SO/sub 2/ had an effect singly, but at the high O/sub 3/ level, the addition of SO/sub 3/ caused an 18.6% reduction in number of tillers. This was the only significant pollutant interaction noted. (JMT)« less

Detection of ozone-induced DNA single strand breaks in murine bronchoalveolar lavage cells acutely exposed in vivo.

PubMed

Haney, J T; Connor, T H; Li, L

1999-04-01

Single-strand breaks (SSBs) in DNA have been used a biomarker of oxidative damage. The comet assay, also known as single-cell gel electrophoresis, was used to investigate the ability of ozone (O(3)) to induce DNA SSBs in murine bronchoalveolar lavage (BAL) cells. The comet assay is more sensitive than other techniques currently utilized for detecting SSBs and requires fewer cells. In the present study, 3 mice were exposed for 3 h to 0.25 ppm of O(3), and 3 to 0.5 ppm of O(3) for 3 h. Two air-exposed mice served as negative controls. All mice were euthanized 3 h after exposure, at which time BAL cells were recovered from the lungs and stained with ethidium bromide. BAL cells recovered from an air-exposed mouse were exposed to various concentrations of H(2)O(2) in vitro for 1 h at 4 degrees C. Excluding cells from the H(2)O(2) group (n = 25), 50 randomly selected BAL cells were graded by comet tail length into 1 of 4 categories: no damage (0 mm), low damage (1-10 mm), medium damage (11-30 mm), and high damage (31 + mm). The nonparametric Wilcoxon rank-sum test was used for statistical analysis, and p values lower than .05 were considered significant. The H(2)O(2) and the 0.25 and 0.5 ppm O3 groups showed statistically significant increases in DNA SSBs as compared to air-exposed controls. The results of this study indicate that (1) O(3) induces DNA strand breaks in murine BAL cells at 0.25 and 0.5 ppm, as evidenced by statistically significant increases in the length of comet tails for O(3)-exposed groups, and (2) the comet assay can be used to assess O(3)-induced SSBs for in vivo exposures. Therefore, it has the potential as a biomarker for in vivo oxidant exposures.

TRPA1 mediates changes in heart rate variability and cardiac mechanical function in mice exposed to acrolein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kurhanewicz, Nicole

Short-term exposure to ambient air pollution is linked with adverse cardiovascular effects. While previous research focused primarily on particulate matter-induced responses, gaseous air pollutants also contribute to cause short-term cardiovascular effects. Mechanisms underlying such effects have not been adequately described, however the immediate nature of the response suggests involvement of irritant neural activation and downstream autonomic dysfunction. Thus, this study examines the role of TRPA1, an irritant sensory receptor found in the airways, in the cardiac response of mice to acrolein and ozone. Conscious unrestrained wild-type C57BL/6 (WT) and TRPA1 knockout (KO) mice implanted with radiotelemeters were exposed once tomore » 3 ppm acrolein, 0.3 ppm ozone, or filtered air. Heart rate (HR) and electrocardiogram (ECG) were recorded continuously before, during and after exposure. Analysis of ECG morphology, incidence of arrhythmia and heart rate variability (HRV) were performed. Cardiac mechanical function was assessed using a Langendorff perfusion preparation 24 h post-exposure. Acrolein exposure increased HRV independent of HR, as well as incidence of arrhythmia. Acrolein also increased left ventricular developed pressure in WT mice at 24 h post-exposure. Ozone did not produce any changes in cardiac function. Neither gas produced ECG effects, changes in HRV, arrhythmogenesis, or mechanical function in KO mice. These data demonstrate that a single exposure to acrolein causes cardiac dysfunction through TRPA1 activation and autonomic imbalance characterized by a shift toward parasympathetic modulation. Furthermore, it is clear from the lack of ozone effects that although gaseous irritants are capable of eliciting immediate cardiac changes, gas concentration and properties play important roles. - Highlights: • Acute acrolein exposure causes autonomic imbalance and altered CV function in mice. • TRPA1 mediates acrolein-induced autonomic nervous system cardiac effects. • Sensory irritation contributes to acrolein-induced cardiac arrhythmia & dysfunction.« less

Survey of fluoride levels in vended water stations.

PubMed

Jadav, Urvi G; Archarya, Bhavini S; Velasquez, Gisela M; Vance, Bradley J; Tate, Robert H; Quock, Ryan L

2014-01-01

This study sought to measure the fluoride concentration of water derived from vended water stations (VWS) and to identify its clinical implications, especially with regard to caries prevention and fluorosis. VWS and corresponding tap water samples were collected from 34 unique postal zip codes; samples were analyzed in duplicate for fluoride concentration. Average fluoride concentration in VWS water was significantly lower than that of tap water (P < 0.001). Fluoride concentration in the VWS water ranged from <0.01 ppm to 0.04 ppm, with a mean concentration of 0.02 ppm (±0.02 ppm). Patients utilizing VWS as their primary source of drinking water may not be receiving optimal caries preventive benefits; thus dietary fluoride supplementation may be indicated. Conversely, to minimize the risk of fluorosis in infants consuming reconstituted infant formula, water from a VWS may be used.

Effect of long-term exposure to fluoride in drinking water on risks of bone fractures.

PubMed

Li, Y; Liang, C; Slemenda, C W; Ji, R; Sun, S; Cao, J; Emsley, C L; Ma, F; Wu, Y; Ying, P; Zhang, Y; Gao, S; Zhang, W; Katz, B P; Niu, S; Cao, S; Johnston, C C

2001-05-01

Findings on the risk of bone fractures associated with long-term fluoride exposure from drinking water have been contradictory. The purpose of this study was to determine the prevalence of bone fracture, including hip fracture, in six Chinese populations with water fluoride concentrations ranging from 0.25 to 7.97 parts per million (ppm). A total of 8266 male and female subjects > or =50 years of age were enrolled. Parameters evaluated included fluoride exposure, prevalence of bone fractures, demographics, medical history, physical activity, cigarette smoking, and alcohol consumption. The results confirmed that drinking water was the only major source of fluoride exposure in the study populations. A U-shaped pattern was detected for the relationship between the prevalence of bone fracture and water fluoride level. The prevalence of overall bone fracture was lowest in the population of 1.00-1.06 ppm fluoride in drinking water, which was significantly lower (p < 0.05) than that of the groups exposed to water fluoride levels > or =4.32 and < or =0.34 ppm. The prevalence of hip fractures was highest in the group with the highest water fluoride (4.32-7.97 ppm). The value is significantly higher than the population with 1.00-1.06 ppm water fluoride, which had the lowest prevalence rate. It is concluded that long-term fluoride exposure from drinking water containing > or =4.32 ppm increases the risk of overall fractures as well as hip fractures. Water fluoride levels at 1.00-1.06 ppm decrease the risk of overall fractures relative to negligible fluoride in water; however, there does not appear to be similar protective benefits for the risk of hip fractures.

High fluoride water in Bondo-Rarieda area of Siaya County, Kenya: a hydro-geological implication on public health in the Lake Victoria Basin.

PubMed

Wambu, Enos W; Agong, Stephen G; Anyango, Beatrice; Akuno, Walter; Akenga, Teresa

2014-05-17

Only a few studies to evaluate groundwater fluoride in Eastern Africa have been undertaken outside the volcanic belt of the Great Eastern Africa Rift Valley. The extent and impact of water fluoride outside these regions therefore remain unclear. The current study evaluated fluoride levels in household water sources in Bondo-Rarieda Area in the Kenyan part of the Lake Victoria Basin (LVB) and highlighted the risk posed by water fluoride to the resident communities. The results, it was anticipated, will contribute to in-depth understanding of the fluoride problem in the region. A total of 128 water samples were collected from different water sources from the entire study area and analyzed for fluoride content using ion-selective electrodes. Lake Victoria was the main water source in the area but dams and open pans (39.5%), boreholes and shallow wells (23.5%), and streams (18.5%) were the principal water sources outside walking distances from the lake. The overall mean fluoride content of the water exceeded recommended limits for drinking water. The mean water fluoride was highest in Uyoma (1.39±0.84 ppm), Nyang'oma (1.00±0.59 ppm) and Asembo (0.92±0.46 ppm) and lowest in Maranda Division (0.69±0.42 ppm). Ponds (1.41±0.82 ppm), springs (1.25±0.43 ppm), dams and open pans (0.96±0.79 ppm), and streams (0.95±0.41 ppm) had highest fluoride levels but lake and river water did not have elevated fluoride levels. Groundwater fluoride decreased with increasing distance from the lake indicating that water fluoride may have hydro-geologically been translocated into the region from geochemical sources outside the area. Lake Victoria was the main water source for the residents of Bondo-Rarieda Area. Majority of in-land residents however used water from dams, open pans, boreholes, shallow wells, ponds and streams, which was generally saline and fluoridated. It was estimated that 36% of children living in this area, who consume water from ground sources from the area could be at the risk of dental fluorosis.

Effects of ozonation pretreatment on natural organic matter and wastewater derived organic matter - Possible implications on the formation of ozonation by-products.

PubMed

Papageorgiou, Alexandros; Stylianou, Stylianos K; Kaffes, Pavlos; Zouboulis, Anastasios I; Voutsa, Dimitra

2017-03-01

The aim of this study was to investigate possible implications of natural and wastewater derived organic matter in river water that is subsequently used following treatment for drinking purposes. River water was subjected to lab-scale ozonation experiments under different ozone doses (0.1, 0.4, 0.8, 1.0 and 2.0 mgO 3 /mgC) and contact times (1, 3, 5, 8 and 10 min). Mixtures of river water with humic acids or wastewaters (sewage wastewater and secondary effluents) at different proportions were also ozonated. Dissolved organic carbon and biodegradable dissolved organic carbon concentrations as well as spectroscopic characteristics (UV absorbance and fluorescence intensities) of different types of dissolved organic matter and possible changes due to the ozonation treatment are presented. River water, humic substances and wastewater exhibited distinct spectroscopic characteristics that could serve for pollution source tracing. Wastewater impacted surface water results in higher formation of carbonyl compounds. However, the formation yield (μg/mgC) of wastewaters was lower than that of surface water possibly due to different composition of wastewater derived organic matter and the presence of scavengers, which may limit the oxidative efficiency of ozone. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of mannose-binding lectin on pulmonary gene expression and innate immune inflammatory response to ozone

PubMed Central

Ciencewicki, Jonathan M.; Verhein, Kirsten C.; Gerrish, Kevin; McCaw, Zachary R.; Li, Jianying; Bushel, Pierre R.

2016-01-01

Ozone is a common, potent oxidant pollutant in industrialized nations. Ozone exposure causes airway hyperreactivity, lung hyperpermeability, inflammation, and cell damage in humans and laboratory animals, and exposure to ozone has been associated with exacerbation of asthma, altered lung function, and mortality. The mechanisms of ozone-induced lung injury and differential susceptibility are not fully understood. Ozone-induced lung inflammation is mediated, in part, by the innate immune system. We hypothesized that mannose-binding lectin (MBL), an innate immunity serum protein, contributes to the proinflammatory events caused by ozone-mediated activation of the innate immune system. Wild-type (Mbl+/+) and MBL-deficient (Mbl−/−) mice were exposed to ozone (0.3 ppm) for up to 72 h, and bronchoalveolar lavage fluid was examined for inflammatory markers. Mean numbers of eosinophils and neutrophils and levels of the neutrophil attractants C-X-C motif chemokines 2 [Cxcl2 (major intrinsic protein 2)] and 5 [Cxcl5 (limb expression, LIX)] in the bronchoalveolar lavage fluid were significantly lower in Mbl−/− than Mbl+/+ mice exposed to ozone. Using genome-wide mRNA microarray analyses, we identified significant differences in transcript response profiles and networks at baseline [e.g., nuclear factor erythroid-related factor 2 (NRF2)-mediated oxidative stress response] and after exposure (e.g., humoral immune response) between Mbl+/+ and Mbl−/− mice. The microarray data were further analyzed to discover several informative differential response patterns and subsequent gene sets, including the antimicrobial response and the inflammatory response. We also used the lists of gene transcripts to search the LINCS L1000CDS2 data sets to identify agents that are predicted to perturb ozone-induced changes in gene transcripts and inflammation. These novel findings demonstrate that targeted deletion of Mbl caused differential levels of inflammation-related gene sets at baseline and after exposure to ozone and significantly reduced pulmonary inflammation, thus indicating an important innate immunomodulatory role of the gene in this model. PMID:27106289

Ozone-Induced Nasal Type 2 Immunity in Mice Is Dependent on Innate Lymphoid Cells.

PubMed

Kumagai, Kazuyoshi; Lewandowski, Ryan; Jackson-Humbles, Daven N; Li, Ning; Van Dyken, Steven J; Wagner, James G; Harkema, Jack R

2016-06-01

Epidemiological studies suggest that elevated ambient concentrations of ozone are associated with activation of eosinophils in the nasal airways of atopic and nonatopic children. Mice repeatedly exposed to ozone develop eosinophilic rhinitis and type 2 immune responses. In this study, we determined the role of innate lymphoid cells (ILCs) in the pathogenesis of ozone-induced eosinophilic rhinitis by using lymphoid-sufficient C57BL/6 mice, Rag2(-/-) mice that are devoid of T cells and B cells, and Rag2(-/-)Il2rg(-/-) mice that are depleted of all lymphoid cells including ILCs. The animals were exposed to 0 or 0.8 ppm ozone for 9 consecutive weekdays (4 h/d). Mice were killed 24 hours after exposure, and nasal tissues were selected for histopathology and gene expression analysis. ILC-sufficient C57BL/6 and Rag2(-/-) mice exposed to ozone developed marked eosinophilic rhinitis and epithelial remodeling (e.g., epithelial hyperplasia and mucous cell metaplasia). Chitinase-like proteins and alarmins (IL-33, IL-25, and thymic stromal lymphopoietin) were also increased morphometrically in the nasal epithelium of ozone-exposed C57BL/6 and Rag2(-/-) mice. Ozone exposure elicited increased expression of Il4, Il5, Il13, St2, eotaxin, MCP-2, Gob5, Arg1, Fizz1, and Ym2 mRNA in C57BL/6 and Rag2(-/-) mice. In contrast, ozone-exposed ILC-deficient Rag2(-/-)Il2rg(-/-) mice had no nasal lesions or overexpression of Th2- or ILC2-related transcripts. These results indicate that ozone-induced eosinophilic rhinitis, nasal epithelial remodeling, and type 2 immune activation are dependent on ILCs. To the best of our knowledge, this is the first study to demonstrate that ILCs play an important role in the nasal pathology induced by repeated ozone exposure.

Efficacy of Ozone against Phosphine Susceptible and Resistant Strains of Four Stored-Product Insect Species

PubMed Central

E, Xinyi; Subramanyam, Bhadriraju; Li, Beibei

2017-01-01

The efficacy of ozone was evaluated against four economically-important stored-product insect species at 27.2 °C and 20.4% r.h. Adults of phosphine-susceptible laboratory strains and phosphine-resistant field strains of the red flour beetle, Tribolium castaneum (Herbst), saw-toothed grain beetle, Oryzaephilus surinamensis (Linnaeus), maize weevil, Sitophilus zeamais Motschulsky, and rice weevil, Sitophilus oryzae (Linnaeus), were exposed in vials to an ozone concentration of 0.42 g/m3 (200 ppm) for 1, 2, 3, 5, 6, 8, 10 and 12 h with 0 and 10 g of wheat. Initial and final mortalities were assessed 1 and 5 d after exposure to ozone, respectively. After an 8–12-h exposure to ozone, initial mortality of Sitophilus spp. and O. surinamensis was 100%, whereas the highest initial mortality of T. castaneum was 90%. A 3–4-h exposure to ozone resulted in 100% final mortality of Sitophilus spp., whereas O. surinamensis required a 6- to 10-h exposure to ozone. Adults of T. castaneum were least susceptible to ozone, and after a 10-h exposure, mortality ranged between 82 and 95%. Time for the 5 d 99% mortality (LT99) for adults of laboratory and field strains of Sitophilus spp., O. surinamensis and T. castaneum were 2.00–5.56, 4.33–11.18 and 14.35–29.89 h, respectively. The LT99 values for adults of T. castaneum and O. surinamensis were not significantly different between bioassays conducted with 0 and 10 g of wheat. The LT99 values for the laboratory strains of Sitophilus spp. in the absence of wheat were significantly lower than those obtained in the presence of wheat. Both phosphine-susceptible and -resistant strains were equally susceptible to ozone. Ozone effectively suppressed adult progeny production of all four species. Ozone is a viable alternative fumigant to control phosphine-resistant strains of these four species. PMID:28398263

Novel Roles for Notch3 and Notch4 Receptors in Gene Expression and Susceptibility to Ozone-Induced Lung Inflammation in Mice

PubMed Central

McCaw, Zachary; Gladwell, Wesley; Trivedi, Shweta; Bushel, Pierre R.; Kleeberger, Steven R.

2015-01-01

Background Ozone is a highly toxic air pollutant and global health concern. Mechanisms of genetic susceptibility to ozone-induced lung inflammation are not completely understood. We hypothesized that Notch3 and Notch4 are important determinants of susceptibility to ozone-induced lung inflammation. Methods Wild-type (WT), Notch3 (Notch3–/–), and Notch4 (Notch4–/–) knockout mice were exposed to ozone (0.3 ppm) or filtered air for 6–72 hr. Results Relative to air-exposed controls, ozone increased bronchoalveolar lavage fluid (BALF) protein, a marker of lung permeability, in all genotypes, but significantly greater concentrations were found in Notch4–/– compared with WT and Notch3–/– mice. Significantly greater mean numbers of BALF neutrophils were found in Notch3–/– and Notch4–/– mice compared with WT mice after ozone exposure. Expression of whole lung Tnf was significantly increased after ozone in Notch3–/– and Notch4–/– mice, and was significantly greater in Notch3–/– compared with WT mice. Statistical analyses of the transcriptome identified differentially expressed gene networks between WT and knockout mice basally and after ozone, and included Trim30, a member of the inflammasome pathway, and Traf6, an inflammatory signaling member. Conclusions These novel findings are consistent with Notch3 and Notch4 as susceptibility genes for ozone-induced lung injury, and suggest that Notch receptors protect against innate immune inflammation. Citation Verhein KC, McCaw Z, Gladwell W, Trivedi S, Bushel PR, Kleeberger SR. 2015. Novel roles for Notch3 and Notch4 receptors in gene expression and susceptibility to ozone-induced lung inflammation in mice. Environ Health Perspect 123:799–805; http://dx.doi.org/10.1289/ehp.1408852 PMID:25658374

77 FR 4937 - Approval and Promulgation of Air Quality Implementation Plans; Texas; Determination of Failure to...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-01

.../region6/r6coment.htm . Please click on ``6PD'' (Multimedia) and select ``Air'' before submitting comments... at least two working days in advance of your visit. There will be a 15 cent per page fee for making... ozone standard of 0.12 parts per million (ppm) (44 FR 8202, February 8, 1979).\\1\\ \\1\\ For ease of...

Efficacy of ozone in killing Listeria monocytogenes on alfalfa seeds and sprouts and effects on sensory quality of sprouts.

PubMed

Wade, W N; Scouten, A J; McWatters, K H; Wick, R L; Demirci, A; Fett, W F; Beuchat, L R

2003-01-01

A study was done to determine the efficacy of aqueous ozone treatment in killing Listeria monocytogenes on inoculated alfalfa seeds and sprouts. Reductions in populations of naturally occurring aerobic microorganisms on sprouts and changes in the sensory quality of sprouts were also determined. The treatment (10 or 20 min) of seeds in water (4 degrees C) containing an initial concentration of 21.8 +/- 0.1 microg/ml of ozone failed to cause a significant (P < or = 0.05) reduction in populations of L. monocytogenes. The continuous sparging of seeds with ozonated water (initial ozone concentration of 21.3 +/- 0.2 microg/ml) for 20 min significantly reduced the population by 1.48 log10 CFU/g. The treatment (2 min) of inoculated alfalfa sprouts with water containing 5.0 +/- 0.5, 9.0 +/- 0.5, or 23.2 +/- 1.6 microg/ml of ozone resulted in significant (P < or = 0.05) reductions of 0.78, 0.81, and 0.91 log10 CFU/g, respectively, compared to populations detected on sprouts treated with water. Treatments (2 min) with up to 23.3 +/- 1.6 microg/ml of ozone did not significantly (P > 0.05) reduce populations of aerobic naturally occurring microorganisms. The continuous sparging of sprouts with ozonated water for 5 to 20 min caused significant reductions in L. monocytogenes and natural microbiota compared to soaking in water (control) but did not enhance the lethality compared to the sprouts not treated with continuous sparging. The treatment of sprouts with ozonated water (20.0 microg/ml) for 5 or 10 min caused a significant deterioration in the sensory quality during subsequent storage at 4 degrees C for 7 to 11 days. Scanning electron microscopy of uninoculated alfalfa seeds and sprouts showed physical damage, fungal and bacterial growth, and biofilm formation that provide evidence of factors contributing to the difficulty of killing microorganisms by treatment with ozone and other sanitizers.

Generation and delivery device for ozone gas

NASA Technical Reports Server (NTRS)

Andrews, Craig C. (Inventor); Murphy, Oliver J. (Inventor)

2002-01-01

The present invention provides an ozone generation and delivery system that lends itself to small scale applications and requires very low maintenance. The system preferably includes an anode reservoir and a cathode phase separator each having a hydrophobic membrane to allow phase separation of produced gases from water. The hydrogen gas, ozone gas and water containing ozone may be delivered under pressure.

Cooling tower water conditioning study. [using ozone

NASA Technical Reports Server (NTRS)

Humphrey, M. F.; French, K. R.

1979-01-01

Successful elimination of cooling tower treatment chemicals was demonstrated. Three towers functioned for long periods of time with ozone as the only treatment for the water. The water in the systems was reused as much as 30 times (cycles of concentration) without deleterious effects to the heat exchangers. Actual system blow-down was eliminated and the only makeup water added was that required to replace the evaporation and mist entrainment losses. Minimum water savings alone are approximately 75.1 1/kg/year. Cost estimates indicate that a savings of 55 percent was obtained on the systems using ozone. A major problem experienced in the use of ozone for cooling tower applications was the difficulty of accurate concentration measurements. The ability to control the operational characteristics relies on easily and accurately determined concentration levels. Present methods of detection are subject to inaccuracies because of interfering materials and the rapid destruction of the ozone.

Structural elucidation of main ozonation products of the artificial sweeteners cyclamate and acesulfame.

PubMed

Scheurer, Marco; Godejohann, Markus; Wick, Arne; Happel, Oliver; Ternes, Thomas A; Brauch, Heinz-Jürgen; Ruck, Wolfgang K L; Lange, Frank Thomas

2012-05-01

The two artificial sweeteners cyclamate (CYC) and acesulfame (ACE) have been detected in wastewater and drinking water treatment plants. As in both facilities ozonation might be applied, it is important to find out if undesired oxidation products (OPs) are formed. For the separation and detection of the OPs, several analytical techniques, including nuclear magnetic resonance experiments, were applied. In order to distinguish between direct ozone reaction and a radical mechanism, experiments were carried out at different pH values with and without scavenging OH radicals. Kinetic experiments were used for confirmation that the OPs are formed during short ozone contact time applied in waterworks. Samples from a waterworks using bank filtrate as raw water were analyzed in order to prove that the identified OPs are formed in real and full-scale ozone applications. In the case of CYC, oxidation mainly occurs at the carbon atom, where the sulfonamide moiety is bound to the cyclohexyl ring. Consequently, amidosulfonic acid and cyclohexanone are formed as main OPs of CYC. When ozone reacts at another carbon atom of the ring a keto moiety is introduced into the CYC molecule. Acetic acid and the product ACE OP170, an anionic compound with m/z=170 and an aldehyde hydrate moiety, were identified as the main OPs for ACE. The observed reaction products suggest an ozone reaction according to the Criegee mechanism due to the presence of a C=C double bond. ACE OP170 was also detected after the ozonation unit of a full-scale drinking water treatment plant which uses surface water-influenced bank filtrate as raw water. Acesulfame can be expected to be found in anthropogenic-influenced raw water used for drinking water production. However, when ACE OP170 is formed during ozonation, it is not expected to cause any problem for drinking water suppliers, because the primary findings suggest its removal in subsequent treatment steps, such as activated carbon filters.

Ozone-induced stomatal sluggishness changes carbon and water balance of temperate deciduous forests.

PubMed

Hoshika, Yasutomo; Katata, Genki; Deushi, Makoto; Watanabe, Makoto; Koike, Takayoshi; Paoletti, Elena

2015-05-06

Tropospheric ozone concentrations have increased by 60-100% in the Northern Hemisphere since the 19(th) century. The phytotoxic nature of ozone can impair forest productivity. In addition, ozone affects stomatal functions, by both favoring stomatal closure and impairing stomatal control. Ozone-induced stomatal sluggishness, i.e., a delay in stomatal responses to fluctuating stimuli, has the potential to change the carbon and water balance of forests. This effect has to be included in models for ozone risk assessment. Here we examine the effects of ozone-induced stomatal sluggishness on carbon assimilation and transpiration of temperate deciduous forests in the Northern Hemisphere in 2006-2009 by combining a detailed multi-layer land surface model and a global atmospheric chemistry model. An analysis of results by ozone FACE (Free-Air Controlled Exposure) experiments suggested that ozone-induced stomatal sluggishness can be incorporated into modelling based on a simple parameter (gmin, minimum stomatal conductance) which is used in the coupled photosynthesis-stomatal model. Our simulation showed that ozone can decrease water use efficiency, i.e., the ratio of net CO2 assimilation to transpiration, of temperate deciduous forests up to 20% when ozone-induced stomatal sluggishness is considered, and up to only 5% when the stomatal sluggishness is neglected.

WATER STRESS REDUCES OZONE INJURY VIA A STOMATAL MECHANISM

EPA Science Inventory

Various studies have shown that water-stressed plants are more tolerant of ozone exposures than are unstressed plants. Two probable explanations for this tolerance are (a) stomatal closure which reduces ozone uptake and (b) biochemical or anatomical changes within the leaves. Pha...

Ozone damage detection in cantaloupe plants

NASA Technical Reports Server (NTRS)

Gausman, H. W.; Escobar, D. E.; Rodriguez, R. R.; Thomas, C. E.; Bowen, R. L.

1978-01-01

Ozone causes up to 90 percent of air pollution injury to vegetation in the United States; excess ozone affects plant growth and development and can cause undetected decrease in yields. Laboratory and field reflectance measurements showed that ozone-damaged cantaloupe (Cucumis melo L.) leaves had lower water contents and higher reflectance than did nondamaged leaves. Cantaloupe plants which were lightly, severely, and very severely ozone-damaged were distinguishable from nondamaged plants by reflectance measurements in the 1.35- to 2.5 micron near-infrared water absorption waveband. Ozone-damaged leaf areas were detected photographically 16 h before the damage was visible. Sensors are available for use with aircraft and spacecraft that possibly could be used routinely to detect ozone-damaged crops.

Chemical reaction rates of ozone in water infusions of wheat, beech, oak and pine leaves of different ages

NASA Astrophysics Data System (ADS)

Potier, Elise; Loubet, Benjamin; Durand, Brigitte; Flura, Dominique; Bourdat-Deschamps, Marjolaine; Ciuraru, Raluca; Ogée, Jérôme

2017-02-01

In this study we present results from a laboratory experiment designed to evaluate the first-order chemical reaction rate (k) of ozone in water films on plant leaves occurring during dew or rain events. Ozone deposition to wet cuticles is indeed known to be a significant pathway of ozone deposition, but the underlying processes are not yet well understood. Leaf infusions obtained by infusing plant leaves with water at room temperature were introduced into a wet effluent denuder fed with a flux of ozone-rich air. Ozone, water vapour concentrations and temperature were measured in both inlet and outlet airflows in order to compute ozone reaction rates kr using an ozone reaction-diffusion model in the water film. Ascorbate solutions were used to validate the set up and led to kr = 3.6 107 M-1 s-1 consistent with the literature. Ozone reaction rates were determined for wheat, beech, oak and pine leaves infusions at several developmental stages, as well as for rain samples. Leaf infusions reaction rates were between 240 s-1 and 3.4 105 s-1 depending on species and developmental stage, while k for rain water ranged from 130 to 830 s-1. Wheat leaves solutions showed significantly (P < 0.001) higher kr (median 73800 s-1) compared to the other tree species (median 4560 s-1). Senescing or dead leaves also showed significantly (P < 0.001) larger k (median 21100 s-1) compared to non-senescent leaves (median 3200 s-1). In wheat, k also increased with increasing yellow leaf fraction. Our results are in the range of previously reported ozone deposition on wet leaves in field or chamber studies. Composition of leaves infusions and previous studies on throughfall and dew composition shows that reaction of ozone with inorganic compounds may only explain the smallest measured k. The largest k observed during senescent are most likely due to reaction with organic material. This is confirmed by LC-MS measurements which showed detection of ascorbate and VOCs as well as the reaction products of ozone with these compounds.

Differential Inactivation of Fungal Spores in Water and on Seeds by Ozone and Arc Discharge Plasma

PubMed Central

Kang, Min Ho; Pengkit, Anchalee; Choi, Kihong; Jeon, Seong Sil; Choi, Hyo Won; Shin, Dong Bum; Choi, Eun Ha; Uhm, Han Sup; Park, Gyungsoon

2015-01-01

Seed sterilization is essential for preventing seed borne fungal diseases. Sterilization tools based on physical technologies have recently received much attention. However, available information is very limited in terms of efficiency, safety, and mode of action. In this study, we have examined antifungal activity of ozone and arc discharge plasma, potential tools for seed sterilization. In our results, ozone and arc discharge plasma have shown differential antifungal effects, depending on the environment associated with fungal spores (freely submerged in water or infected seeds). Ozone inactivates Fusarium fujikuroi (fungus causing rice bakanae disease) spores submerged in water more efficiently than arc discharge plasma. However, fungal spores associated with or infecting rice seeds are more effectively deactivated by arc discharge plasma. ROS generated in water by ozone may function as a powerful fungicidal factor. On the other hand, shockwave generated from arc discharge plasma may have greatly contributed to antifungal effects on fungus associated with rice seeds. In support of this notion, addition of ultrasonic wave in ozone generating water has greatly increased the efficiency of seed disinfection. PMID:26406468

Low temperature destruction of PCDD/Fs over V2O5-CeO2/TiO2 catalyst with ozone.

PubMed

Yu, Ming-Feng; Lin, Xiao-Qing; Yan, Mi; Li, Xiao-Dong; Chen, Tong; Yan, Jian-Hua

2016-09-01

Catalytic destruction of PCDD/Fs (polychlorinated dibenzo-p-dioxins and furans) over V2O5-CeO2/TiO2 catalyst was investigated at a low temperature range of 140-180 °C, in the absence and presence of ozone (200 ppm). Nano-TiO2 support was used to prepare the catalyst by step impregnation method. A stable PCDD/Fs-generating system was established to support the catalytic destruction tests. In the presence of ozone alone, destruction efficiencies of PCDD/Fs are between 32.2 and 43.1 % with temperature increasing from 140 to 180 °C. The activity of V2O5-CeO2/TiO2 catalyst alone on PCDD/Fs destruction is also studied. The increase of temperature from 140 to 180 °C enhances the activity of catalyst with destruction efficiencies increasing from 54.7 to 73.4 %. However, ozone addition greatly enhances the catalytic activity of V2O5-CeO2/TiO2 catalyst on PCDD/Fs decomposition. At 180 °C, the destruction efficiency of PCDD/Fs achieved with V2O5-CeO2/TiO2 catalyst and ozone is above 86.0 %. It indicates that the combined use of ozone and catalyst reduces the reaction temperature of PCDD/Fs oxidation and offers a new method to destroy PCDD/Fs with high destruction efficiency at a low temperature. Furthermore, the destruction efficiencies of 17 toxic PCDD/F congeners, achieved with ozone alone, catalyst alone, and catalyst/ozone are analyzed.

Ozone modifies the metabolic and endocrine response to glucose: Reproduction of effects with the stress hormone corticosterone.

PubMed

Thomson, Errol M; Pilon, Shinjini; Guénette, Josée; Williams, Andrew; Holloway, Alison C

2018-03-01

Air pollution is associated with increased incidence of metabolic disease (e.g. metabolic syndrome, obesity, diabetes); however, underlying mechanisms are poorly understood. Air pollutants increase the release of stress hormones (human cortisol, rodent corticosterone), which could contribute to metabolic dysregulation. We assessed acute effects of ozone, and stress axis involvement, on glucose tolerance and on the metabolic (triglyceride), endocrine/energy regulation (insulin, glucagon, GLP-1, leptin, ghrelin, corticosterone), and inflammatory/endothelial (TNF, IL-6, VEGF, PAI-1) response to exogenous glucose. Male Fischer-344 rats were exposed to clean air or 0.8 ppm ozone for 4 h in whole body chambers. Hypothalamic-pituitary-adrenal (HPA) axis involvement in ozone effects was tested through subcutaneous administration of the glucocorticoid synthesis inhibitor metyrapone (50 mg/kg body weight), corticosterone (10 mg/kg body weight), or vehicle (40% propylene glycol) prior to exposure. A glucose tolerance test (2 g/kg body weight glucose) was conducted immediately after exposure, with blood samples collected at 0, 30, 60, 90, and 120 min. Ozone exposure impaired glucose tolerance, an effect accompanied by increased plasma triglycerides but no impairment of insulin release. Ozone diminished glucagon, GLP-1, and ghrelin responses to glucose, but did not significantly impact inflammatory/endothelial analytes. Metyrapone reduced corticosterone but increased glucose and triglycerides, complicating evaluation of the impact of glucocorticoid inhibition. However, administration of corticosterone reproduced the profile of ozone effects, supporting a role for the HPA axis. The results show that ozone-dependent changes in glucose tolerance are accompanied by altered metabolic and endocrine responses to glucose challenge that are reproduced by exogenous stress hormone. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

The maintenance of elevated active chlorine levels in the Antarctic lower stratosphere through HCl null cycles

NASA Astrophysics Data System (ADS)

Müller, Rolf; Grooß, Jens-Uwe; Mannan Zafar, Abdul; Robrecht, Sabine; Lehmann, Ralph

2018-03-01

The Antarctic ozone hole arises from ozone destruction driven by elevated levels of ozone destroying (active) chlorine in Antarctic spring. These elevated levels of active chlorine have to be formed first and then maintained throughout the period of ozone destruction. It is a matter of debate how this maintenance of active chlorine is brought about in Antarctic spring, when the rate of formation of HCl (considered to be the main chlorine deactivation mechanism in Antarctica) is extremely high. Here we show that in the heart of the ozone hole (16-18 km or 85-55 hPa, in the core of the vortex), high levels of active chlorine are maintained by effective chemical cycles (referred to as HCl null cycles hereafter). In these cycles, the formation of HCl is balanced by immediate reactivation, i.e. by immediate reformation of active chlorine. Under these conditions, polar stratospheric clouds sequester HNO3 and thereby cause NO2 concentrations to be low. These HCl null cycles allow active chlorine levels to be maintained in the Antarctic lower stratosphere and thus rapid ozone destruction to occur. For the observed almost complete activation of stratospheric chlorine in the lower stratosphere, the heterogeneous reaction HCl + HOCl is essential; the production of HOCl occurs via HO2 + ClO, with the HO2 resulting from CH2O photolysis. These results are important for assessing the impact of changes of the future stratospheric composition on the recovery of the ozone hole. Our simulations indicate that, in the lower stratosphere, future increased methane concentrations will not lead to enhanced chlorine deactivation (through the reaction CH4 + Cl → HCl + CH3) and that extreme ozone destruction to levels below ≈ 0.1 ppm will occur until mid-century.

Preexposure to ozone blocks the antigen-induced late asthmatic response of the canine peripheral airways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turner, C.R.; Kleeberger, S.R.; Spannhake, E.W.

1989-01-01

The influence of exposure of the airways to ozone on acute allergic responsiveness has been investigated in several species. Little is known, however, about the effect of this environmental pollutant on the late asthmatic response (LAR) in animals in which it is exhibited. The purpose of this study was to evaluate this effect in the canine peripheral airways and to assess the potential role of mast cells in modulating the effect. A series of experiments on seven mongrel dogs demonstrated that the numbers of mast cells at the base of the epithelial region of small subsegmental airways exposed to 1more » ppm ozone for 5 min were significantly (p less than .01) increased 3 h following exposure compared to air exposed or nonexposed control airways. In a second series of experiments performed on eight additional mongrel dogs with inherent sensitivity to Ascaris suum antigen, antigen aerosol was administered to the sublobar segment 3 h following ozone preexposure when mast cell numbers were presumed to be increased. These experiments were performed to determine whether ozone preexposure could enhance the late-phase response to antigen by virtue of acutely increasing the number of mast cells available to bind the antigen. Four of the eight dogs tested displayed a late-phase response to antigen following air-sham preexposure. In these four dogs, simultaneous ozone preexposure of a contralateral lobe completely blocked the late-phase response to antigen. These results indicate that the consequences of a single exposure to ozone persist beyond its effects on acute antigen-induced bronchoconstriction and extend to the complex processes involved with the late response. This attenuating effect of ozone is seen under conditions where mast-cell numbers in the airways are increased above baseline levels.« less

Effect of thromboxane antagonists on ozone-induced airway responses in dogs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, G.L.; Lane, C.G.; O'Byrne, P.M.

1990-09-01

Airway hyperresponsiveness after inhaled ozone in dogs may occur as a result of thromboxane release in the airway. In this study, two thromboxane receptor antagonists, L-655,240 and L-670,596, were used in doses that inhibit the response to an inhaled thromboxane mimetic, U-46619, to determine further the role of thromboxane in ozone-induced airway hyperresponsiveness. Dogs were studied on 2 days separated by 1 wk. On each day, the dogs inhaled ozone (3 ppm) for 30 min. On one randomly assigned day, 10 dogs received an infusion of L-655,240 (5 mg.kg-1.h-1) and 5 dogs received an infusion of L-670,596 (1 mg.kg-1.h-1); onmore » the other day dogs received a control infusion. Airway responses to doubling doses of acetylcholine were measured before and after inhalation of ozone and were expressed as the concentration of acetylcholine giving a rise in resistance of 5 cmH2O.l-1.s from baseline (acetylcholine provocation concentration). The development of airway hyperresponsiveness after ozone was not inhibited by the thromboxane antagonists. The mean log difference in the acetylcholine provocative concentration before and after ozone on the L-655,240 treatment day was 0.62 +/- 0.12 (SE) and on the control day was 0.71 +/- 0.12 (P = 0.48); on the L-670,596 treatment day the mean log difference was 0.68 +/- 0.15 (SE) and on the control day it was 0.75 +/- 0.19 (P = 0.45). These results do not support an important role for thromboxane in causing ozone-induced airway hyperresponsiveness.« less

Effects of ozone on the cholinergic secretory responsiveness of ferret tracheal glands

DOE Office of Scientific and Technical Information (OSTI.GOV)

McBride, R.K.; Oberdoerster, G.; Marin, M.G.

1991-06-01

Oxidant air pollutants exacerbate several pulmonary diseases. Inhalation of ozone has been shown to induce airway smooth muscle hyperresponsiveness. Oxidant injury could also affect airway secretory mechanisms. The authors postulated that oxidant exposure would alter the glycoconjugate secretory function of airway submucosal glands. To test this hypothesis they examined the effects of in vivo ozone exposure on the in vitro secretory responsiveness of ferret tracheal glands. Ferrets were exposed to 1 ppm ozone, 24 hr/day for 3 or 7 days. Following exposure, glandular explants, denuded of surface epithelial cells, were prepared and incubated in medium containing 3H-glucosamine for 18 hr.more » Basal secretion of labeled glycoconjugates was significantly increased 31% following 3 days of ozone exposure (P less than or equal to 0.05) and remained elevated 11% after 7 days of exposure compared to the air-exposed group. After 3 or 7 days of exposure to ozone, tracheal gland responsiveness to carbachol was increased as indicated by significantly lower EC50 values (log molar concentration) of -6.43 {plus minus} 0.04 (n = 6) and -6.50 {plus minus} 0.11 (n = 5), respectively; compared to -6.20 {plus minus} 0.08 (n = 6) for the air-exposed group. There was no difference in carbachol EC50 values for air and 7-day ozone-exposed animals treated with dexamethasone. Dexamethasone did not attenuate the ozone-induced increase in basal secretion. Tracheal gland responsiveness to {alpha}- or {beta}-adrenergic agonists was not changed by oxidant exposure. These experiments suggest that oxidant injury not only increases basal secretion of respiratory glycoconjugates but also increases tracheal gland sensitivity to a cholinergic agonist.« less

Production of reactive species using vacuum ultraviolet photodissociation as a tool for studying their effects in plasma medicine: simulations and measurements

NASA Astrophysics Data System (ADS)

Ono, Ryo; Tokumitsu, Yusuke; Zen, Shungo; Yonemori, Seiya

2014-11-01

We propose a method for producing OH, H, O, O3, and O2(a1Δg) using the vacuum ultraviolet photodissociation of H2O and O2 as a tool for studying the reaction processes of plasma medicine. For photodissociation, an H2O/He or O2/He mixture flowing in a quartz tube is irradiated by a Xe2 or Kr2 excimer lamp. The effluent can be applied to a target. Simulations show that the Xe2 lamp method can produce OH radicals within 0.1-1 ppm in the effluent at 5 mm from a quartz tube nozzle. This is comparable to those produced by a helium atmospheric-pressure plasma jet (He-APPJ) currently used in plasma medicine. The Xe2 lamp method also produces H atoms of, at most, 6 ppm. In contrast, the maximum O densities produced by the Xe2 and Kr2 lamp methods are 0.15 ppm and 2.5 ppm, respectively; these are much lower than those from He-APPJ (several tens of ppm). Both lamp methods can produce ozone at concentrations above 1000 ppm and O2(a1Δg) at tens of ppm. The validity of the simulations is verified by measuring the O3 and OH densities produced by the Xe2 lamp method using ultraviolet absorption and laser-induced fluorescence. The differences between the measured and simulated densities for O3 and OH are 20% and factors of 3-4, respectively.

INACTIVATION OF HEPATITIS A VIRUS AND MS2 BY OZONE AND OZONE-HYDROGEN PEROXIDE IN BUFFERED WATER

EPA Science Inventory

Disinfection of drinking water by chlorine is a primary means of preventing the transmission of waterborne disease, and its efficacy is well-established. The comparative inactivation of highly purified hepatitis A virus (HAV) and MS2 by 1 mg water/L, 2.0 and 0.4 mg ozone/L plus 0...

Soil Water Availability Modulation Over Estimated Relative Yield Losses in Wheat (Triticum aestivum L.) Due to Ozone Exposure

PubMed Central

De la Torre, Daniel; Sierra, Maria Jose

2007-01-01

The approach developed by Fuhrer in 1995 to estimate wheat yield losses induced by ozone and modulated by the soil water content (SWC) was applied to the data on Catalonian wheat yields. The aim of our work was to apply this approach and adjust it to Mediterranean environmental conditions by means of the necessary corrections. The main objective pursued was to prove the importance of soil water availability in the estimation of relative wheat yield losses as a factor that modifies the effects of tropospheric ozone on wheat, and to develop the algorithms required for the estimation of relative yield losses, adapted to the Mediterranean environmental conditions. The results show that this is an easy way to estimate relative yield losses just using meteorological data, without using ozone fluxes, which are much more difficult to calculate. Soil water availability is very important as a modulating factor of the effects of ozone on wheat; when soil water availability decreases, almost twice the amount of accumulated exposure to ozone is required to induce the same percentage of yield loss as in years when soil water availability is high. PMID:17619747

Long-term greenhouse gas measurements from aircraft

NASA Astrophysics Data System (ADS)

Karion, A.; Sweeney, C.; Wolter, S.; Newberger, T.; Chen, H.; Andrews, A.; Kofler, J.; Neff, D.; Tans, P.

2013-03-01

In March 2009 the NOAA/ESRL/GMD Carbon Cycle and Greenhouse Gases Group collaborated with the US Coast Guard (USCG) to establish the Alaska Coast Guard (ACG) sampling site, a unique addition to NOAA's atmospheric monitoring network. This collaboration takes advantage of USCG bi-weekly Arctic Domain Awareness (ADA) flights, conducted with Hercules C-130 aircraft from March to November each year. Flights typically last 8 h and cover a large area, traveling from Kodiak up to Barrow, Alaska, with altitude profiles near the coast and in the interior. NOAA instrumentation on each flight includes a flask sampling system, a continuous cavity ring-down spectroscopy (CRDS) carbon dioxide (CO2)/methane (CH4)/carbon monoxide (CO)/water vapor (H2O) analyzer, a continuous ozone analyzer, and an ambient temperature and humidity sensor. Air samples collected in flight are analyzed at NOAA/ESRL for the major greenhouse gases and a variety of halocarbons and hydrocarbons that influence climate, stratospheric ozone, and air quality. We describe the overall system for making accurate greenhouse gas measurements using a CRDS analyzer on an aircraft with minimal operator interaction and present an assessment of analyzer performance over a three-year period. Overall analytical uncertainty of CRDS measurements in 2011 is estimated to be 0.15 ppm, 1.4 ppb, and 5 ppb for CO2, CH4, and CO, respectively, considering short-term precision, calibration uncertainties, and water vapor correction uncertainty. The stability of the CRDS analyzer over a seven-month deployment period is better than 0.15 ppm, 2 ppb, and 4 ppb for CO2, CH4, and CO, respectively, based on differences of on-board reference tank measurements from a laboratory calibration performed prior to deployment. This stability is not affected by variation in pressure or temperature during flight. We conclude that the uncertainty reported for our measurements would not be significantly affected if the measurements were made without in-flight calibrations, provided ground calibrations and testing were performed regularly. Comparisons between in situ CRDS measurements and flask measurements are consistent with expected measurement uncertainties for CH4 and CO, but differences are larger than expected for CO2. Biases and standard deviations of comparisons with flask samples suggest that atmospheric variability, flask-to-flask variability, and possible flask sampling biases may be driving the observed flask versus in situ CO2 differences rather than the CRDS measurements.

Effect of ozone on diverse tall fescue germplasm

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnston, W.J.; Dickens, R.; Haaland, R.L.

Six tall fescue (Festuca arundinacea Schreb.) genotypes of diverse origin (Algeria, Australia, France, Netherlands, Morocco, and a Kentucky 31 type) were evaluated for O/sub 3/ tolerance under controlled environmental conditions. In two tests on clonal parent material, (1) O/sub 3/ constant 0.3 ppm and exposure varied 0-12 hr and (2) O/sub 3/ concentration varied 0-0.5 ppm and exposure varied 1-3 hr, the Australian and Kentucky 31 selections were superior to all others in O/sub 3/ tolerance. Sixteen-day old polycross progeny of the six selections were exposed to 0.5 ppm O/sub 3/ for 0, 3, or 6 hr. Progeny of themore » Australian and Kentucky 31 selections were superior to some, but not all other selections. Increased duration of exposure increased damage only slightly. It would appear that O/sub 3/ tolerance is a heritable characteristic that can be easily detected and selected for in tall fescue.« less

Non-thermal combined treatments in the processing of açai (Euterpe oleracea) juice.

PubMed

Oliveira, Ana Flávia A; Mar, Josiana M; Santos, Samara F; da Silva Júnior, Joel L; Kluczkovski, Ariane M; Bakry, Amr M; Bezerra, Jaqueline de Araújo; Nunomura, Rita de Cássia Saraiva; Sanches, Edgar A; Campelo, Pedro H

2018-11-01

Quality parameters of açai juice processed with ultrasound-assisted, ozone and the combined methods were analyzed in this work. Two ultrasound energy densities (350 and 700 J·mL -1 ) and two ozonization times (5 and 10 min with 1.5 ppm) were analyzed for pure açai juice and 8 different treatments (2 2 complete factorial). To evaluate the quality parameters of the juice, physical-chemical analyzes such as pH, titratable acidity, cloud value, non-enzymatic browning, rheology, antioxidant activity (DPPH and ABTS), phenolic compounds, anthocyanins, enzymatic activity (peroxidase and polyphenol oxidase) and microbial counts (mesophilic bacteria, molds and yeasts) were conducted. The treatments with ozone were better for microbial inactivation and the ultrasound for enzymatic inactivation. In general, the use of non-thermal methods can be a good alternative for the processing of açai juice. Copyright © 2018 Elsevier Ltd. All rights reserved.

Reformulated gasolines: The experience of Mexico City Metropolitan Zone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alvarez, H.B.; Jardon, R.T.; Echeverria, R.S.

1997-12-31

The introduction of several reformulated gasolines into the Mexico City Metropolitan Zone (MCMZ) in the middle 1986 is an example of using fuel composition to improve, in theory, the air quality. However, although these changes have resulted in an important reduction of lead airborne concentrations, a worsened situation has been created. Ozone levels in the atmosphere MCMZ have presented a sudden rise since the introduction of the first reformulated gasoline, reaching in the 1990`s an annual average of 1,700 exceedances to the Mexican Ozone Air Quality Standard (0.11 ppm not to be exceeded 1 hr. a day one day amore » year). The authors examine the tendency on ozone air quality in MCMZ in relation with the changes in gasoline composition since 1986. The authors also discuss the importance to perform an air quality impact analysis before the introduction of reformulated gasolines in countries where the local economy do not allow to change the old car fleet not fitted with exhaust treatment devices.« less

Trimodal distribution of ozone and water vapor in the UT/LS during boreal summer

NASA Astrophysics Data System (ADS)

Dunkerton, T. J.

2004-12-01

The relation of ozone and water vapor in the upper troposphere and lower stratosphere (UT/LS) is strongly influenced by the off-equatorial Asian and North American monsoons in boreal summer. Both regions experience hydration, presumably as a result of deep convection. This behavior contrasts sharply with the apparent dehydrating influence of near-equatorial deep convection in boreal winter. There is also a striking difference in ozone between Asia and North America in boreal summer. Over Asia, ozone concentrations are low, evidently a result of ubiquitous deep convection and the vertical transport of ozone-poor air, while over North America, ozone concentrations are much higher. Since deep convection also occurs in the North American monsoon, it appears that the difference in ozone concentration between Asia and North America in boreal summer reflects a differing influence of the large-scale circulation in the two regions: specifically, (i) isolation of the Tibetan anticyclone versus (ii) the intrusion of filaments of ozone-rich air from the stratosphere over North America. During boreal summer, as in winter, near-equatorial concentrations of ozone and water vapor are low near the equator. The result of these geographical variations is a trimodal distribution of ozone and water-vapor correlation. Our talk reviews the observational evidence of this trimodal distribution and possible dynamical and microphysical causes, focusing primarily on the quality and possible sampling bias of satellite and aircraft measurements. A key issue is the ability of HALOE to sample areas of ubiquitous deep convection. Other issues include the vertical structure of tracer anomalies, isentropic stirring in the UT/LS, horizontal transport of biomass burning products lofted by deep convection, and connections to the moist phase of the tropical `tape recorder' signal in water vapor.

Trimodal distribution of ozone and water vapor in the UT/LS during boreal summer

NASA Astrophysics Data System (ADS)

Dunkerton, T. J.

2004-05-01

The relation of ozone and water vapor in the upper troposphere and lower stratosphere (UT/LS) is strongly influenced by the off-equatorial Asian and North American monsoons in boreal summer. Both regions experience hydration, presumably as a result of deep convection. This behavior contrasts sharply with the apparent dehydrating influence of near-equatorial deep convection in boreal winter. There is also a striking difference in ozone between Asia and North America in boreal summer. Over Asia, ozone concentrations are low, evidently a result of ubiquitous deep convection and the vertical transport of ozone-poor air, while over North America, ozone concentrations are much higher. Since deep convection also occurs in the North American monsoon, it appears that the difference in ozone concentration between Asia and North America in boreal summer reflects a differing influence of the large-scale circulation in the two regions: specifically, (i) isolation of the Tibetan anticyclone versus (ii) the intrusion of filaments of ozone-rich air from the stratosphere over North America. During boreal summer, as in winter, near-equatorial concentrations of ozone and water vapor are low near the equator. The result of these geographical variations is a trimodal distribution of ozone and water-vapor correlation. Our talk reviews the observational evidence of this trimodal distribution and possible dynamical and microphysical causes, focusing primarily on the quality and possible sampling bias of satellite and aircraft measurements. A key issue is the ability of HALOE to sample areas of ubiquitous deep convection. Other issues include the vertical structure of tracer anomalies, isentropic stirring in the UT/LS, horizontal transport of biomass burning products lofted by deep convection, and connections to the moist phase of the tropical `tape recorder' signal in water vapor.

Effect of ozone to remineralize initial enamel caries: in situ study.

PubMed

Samuel, S R; Dorai, S; Khatri, S G; Patil, S T

2016-06-01

Effect of ozonated water in remineralizing artificially created initial enamel caries was investigated using laser fluorescence and polarized light microscopy in an in situ study. Teeth specimens (buccal sections) were immersed in 5-ml solution of 2 mM CaCl2, 2 mM NaH2P04, and 50 mM CH3COOH at pH of 4.55 for 5 h in an incubator at 37° to create subsurface demineralization. After which, they were randomly allocated into one of the following remineralization regimens: ozone (ozonated water 0.1 mg/l and 10 % nano-hydroxyapatite paste, Aclaim(TM)), without ozone (only 10 % nano-hydroxyapatite paste, Aclaim(TM)), and control (subjects' saliva alone). Specimens were embedded in acrylic retainers worn by orthodontic patients throughout the 21-day study duration and constantly exposed to their saliva. Laser fluorescence was recorded for all the specimens at baseline, after demineralization, and remineralization using DIAGNOdent, and the results were validated using polarized microscopic examination. The results were analyzed using repeated measures, one-way ANOVA with post hoc multiple comparisons. Reduced DIAGNOdent scores and greater depth of remineralization following application of ozonated water and nano-hydroxyapatite were found compared to those of the without ozone and control groups (P < 0.001), and the ozone-treated group exhibited maximum remineralization under the polarized light microscopy. Ozonated water can be considered an effective agent in reversing the initial enamel caries alongside with nano-hydroxyapatite compared to nano-hydroxyapatite alone and saliva. Ozone water can be used to remineralize incipient carious lesions, and it enhances the remineralizing potential of nano-hydroxyapatite thereby preventing the tooth from entering into the repetitive restorative cycle.

Generation of ozone by pulsed corona discharge over water surface in hybrid gas liquid electrical discharge reactor

NASA Astrophysics Data System (ADS)

Lukes, Petr; Clupek, Martin; Babicky, Vaclav; Janda, Vaclav; Sunka, Pavel

2005-02-01

Ozone formation by a pulse positive corona discharge generated in the gas phase between a planar high voltage electrode made from reticulated vitreous carbon and a water surface with an immersed ground stainless steel plate electrode was investigated under various operating conditions. The effects of gas flow rate (0.5-3 litre min-1), discharge gap spacing (2.5-10 mm), applied input power (2-45 W) and gas composition (oxygen containing argon or nitrogen) on ozone production were determined. Ozone concentration increased with increasing power input and with increasing discharge gap. The production of ozone was significantly affected by the presence of water vapour formed through vaporization of water at the gas-liquid interface by the action of the gas phase discharge. The highest energy efficiency for ozone production was obtained using high voltage pulses of approximately 150 ns duration in Ar/O2 mixtures with the maximum efficiency (energy yield) of 23 g kW h-1 for 40% argon content.

Formation and emissions of carbonyls during and following gas-phase ozonation of indoor materials

NASA Astrophysics Data System (ADS)

Poppendieck, D. G.; Hubbard, H. F.; Weschler, C. J.; Corsi, R. L.

Ozone concentrations that are several orders of magnitude greater than typical urban ambient concentrations are necessary for gas-phase ozonation of buildings, either for deodorization or for disinfection of biological agents. However, there is currently no published literature on the interaction of building materials and ozone under such extreme conditions. It would be useful to understand, for example in the case of building re-occupation planning, what types and amounts of reaction products may form and persist in a building after ozonation. In this study, 24 materials were exposed to ozone at concentrations of 1000 ppm in the inlet stream of experimental chambers. Fifteen target carbonyls were selected and measured as building ozonation by-products (BOBPs). During the 36 h that include the 16 h ozonation and 20 h persistence phase, the total BOBP mass released from flooring and wall coverings ranged from 1 to 20 mg m -2, with most of the carbonyls being of lower molecular weight (C 1-C 4). In contrast, total BOBP mass released from wood-based products ranged from 20 to 100 mg m -2, with a greater fraction of the BOBPs being heavier carbonyls (C 5-C 9). The total BOBP mass released during an ozonation event is a function of both the total surface area of the material and the BOBP emission rate per unit area of material. Ceiling tile, carpet, office partition, and gypsum wallboard with flat latex paint often have large surface areas in commercial buildings and these same materials exhibited relatively high BOBP releases. The greatest overall BOBP mass releases were observed for three materials that building occupants might have significant contact with: paper, office partition, and medium density fiberboard, e.g., often used in office furniture. These materials also exhibited extended BOBP persistence following ozonation; some BOBPs (e.g., nonanal) persist for months or more at emission rates large enough to result in indoor concentrations that exceed their odor threshold.

Comparison of methylisoborneol and geosmin abatement in surface water by conventional ozonation and an electro-peroxone process.

PubMed

Yao, Weikun; Qu, Qiangyong; von Gunten, Urs; Chen, Chao; Yu, Gang; Wang, Yujue

2017-01-01

In this study methylisoborneol (MIB) and geosmin abatement in a surface water by conventional ozonation and the electro-peroxone (E-peroxone) process was compared. Batch tests with addition of ozone (O 3 ) stock solutions and semi-batch tests with continuous O 2 /O 3 gas sparging (simulating real ozone contactors) were conducted to investigate O 3 decomposition, •OH production, MIB and geosmin abatement, and bromate formation during the two processes. Results show that with specific ozone doses typically used in routine drinking water treatment (0.5-1.0 mg O 3 /mg dissolved organic carbon (DOC)), conventional ozonation could not adequately abate MIB and geosmin in a surface water. While increasing the specific ozone doses (1.0-2.5 mg O 3 /mg DOC) could enhance MIB and geosmin abatement by conventional ozonation, this approach resulted in significant bromate formation. By installing a carbon-based cathode to electrochemically produce H 2 O 2 from cathodic oxygen reduction, conventional ozonation can be conveniently upgraded to an E-peroxone process. The electro-generated H 2 O 2 considerably enhanced the kinetics and to a lesser extent the yields of hydroxyl radical (•OH) from O 3 decomposition. Consequently, during the E-peroxone process, abatement of MIB and geosmin occurred at much higher rates than during conventional ozonation. In addition, for a given specific ozone dose, the MIB and geosmin abatement efficiencies increased moderately in the E-peroxone (by ∼8-9% and ∼10-25% in the batch and semi-batch tests, respectively) with significantly lower bromate formation compared to conventional ozonation. These results suggest that the E-peroxone process may serve as an attractive backup of conventional ozonation processes during accidental spills or seasonal events such as algal blooms when high ozone doses are required to enhance MIB and geosmin abatement. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fish oil and olive oil-rich diets modify ozone-induced ...

EPA Pesticide Factsheets

Rationale: Air pollution exposure has been associated with adverse cardiovascular health effects. Our clinical studies suggest that fish oil (FO) and olive oil (OO) supplementations attenuate the cardiovascular responses to inhaled concentrated ambient particles. This study was designed to examine the cardiovascular effects of ozone and the efficacy of FO and OO-rich diets in attenuating these effects of ozone exposure in rats. Methods: Male Wistar Kyoto rats were fed either a normal diet (ND), or a diet enriched with 6% FO or OO starting at 4 weeks of age. Eight weeks following the start of the diet, animals were exposed to filtered air (FA) or 0.8 ppm ozone, 4 hr/day for 2 consecutive days. Immediately after exposure, cardiac responses were assessed ex vivo using a Langendorff heart preparation with a protocol consisting of 20 min of global ischemia followed by 2 hr reperfusion. Cardiac function was measured as the index of left-ventricular developed pressure (LVDP) and contractility (dP/dtmax and dP/dtmin) before ischemia. Upon reperfusion after ischemia, the recovery of post-ischemic LVDP and infarct size were examined. Results: The pre-ischemic LVDP, dP/dtmax, and dP/dtmin were lower after ozone exposure when compared to the FA control in the rats fed ND but not FO and OO. OO diet shortened the time to ischemic contracture of the hearts after FA exposure compared to ND. Ozone exposure increased pre-ischemic heart rate and the time to ischemic contractur

Ozone uptake, water loss and carbon exchange dynamics in annually drought-stressed Pinus ponderosa forests: measured trends and parameters for uptake modeling.

PubMed

Panek, Jeanne A

2004-03-01

This paper describes 3 years of physiological measurements on ponderosa pine (Pinus ponderosa Dougl. ex Laws.) growing along an ozone concentration gradient in the Sierra Nevada, California, including variables necessary to parameterize, validate and modify photosynthesis and stomatal conductance algorithms used to estimate ozone uptake. At all sites, gas exchange was under tight stomatal control during the growing season. Stomatal conductance was strongly correlated with leaf water potential (R2=0.82), which decreased over the growing season with decreasing soil water content (R2=0.60). Ozone uptake, carbon uptake, and transpirational water loss closely followed the dynamics of stomatal conductance. Peak ozone and CO2 uptake occurred in early summer and declined progressively thereafter. As a result, periods of maximum ozone uptake did not correspond to periods of peak ozone concentration, underscoring the inappropriateness of using current metrics based on concentration (e.g., SUM0, W126 and AOT40) for assessing ozone exposure risk to plants in this climate region. Both Jmax (maximum CO2-saturated photosynthetic rate, limited by electron transport) and Vcmax (maximum rate of Rubisco-limited carboxylation) increased toward the middle of the growing season, then decreased in September. Intrinsic water-use efficiency rose with increasing drought stress, as expected. The ratio of Jmax to Vcmax was similar to literature values of 2.0. Nighttime respiration followed a Q10 of 2.0, but was significantly higher at the high-ozone site. Respiration rates decreased by the end of the summer as a result of decreased metabolic activity and carbon stores.

Water Content of the Oceanic Lithosphere at Hawaii from FTIR Analysis of Peridotite Xenoliths

NASA Technical Reports Server (NTRS)

Peslier, Anne H.; Bizmis, Michael

2013-01-01

Although water in the mantle is mostly present as trace H dissolved in minerals, it has a large influence on its melting and rheological properties. The water content of the mantle lithosphere beneath continents is better constrained by abundant mantle xenolith data than beneath oceans where it is mainly inferred from MORB glass analysis. Using Fourier transform infrared (FTIR) spectrometry, we determined the water content of olivine (Ol), clinopyroxene (Cpx) and orthopyroxene (Opx) in spinel peridotite xenoliths from Salt Lake Crater, Oahu, Hawaii, which are thought to represent fragments of the Pacific oceanic lithosphere that was refertilized by alkalic Hawaiian melts. Only Ol exhibits H diffusion profiles, evidence of limited H loss during xenolith transport to the surface. Water concentrations (Ol: 9-28 ppm H2O, Cpx: 246-566 ppm H2O, Opx: 116-224 ppm H2O) are within the range of those from continental settings but higher than those from Gakkel ridge abyssal peridotites. The Opx H2O contents are similar to those of abyssal peridotites from Atlantic ridge Leg 153 (170-230 ppm) but higher than those from Leg 209 (10- 14 ppm). The calculated bulk peridotite water contents (94 to 144 ppm H2O) are in agreement with MORB mantle source water estimates and lower than estimates for the source of Hawaiian rejuvenated volcanism (approx 540 ppm H2O) . The water content of Cpx and most Opx correlates negatively with spinel Cr#, and positively with pyroxene Al and HREE contents. This is qualitatively consistent with the partitioning of H into the melt during partial melting, but the water contents are too high for the degree of melting these peridotites experienced. Melts in equilibrium with xenolith minerals have H2O/Ce ratios similar to those of OIB

High fluoride water in Bondo-Rarieda area of Siaya County, Kenya: a hydro-geological implication on public health in the Lake Victoria Basin

PubMed Central

2014-01-01

Background Only a few studies to evaluate groundwater fluoride in Eastern Africa have been undertaken outside the volcanic belt of the Great Eastern Africa Rift Valley. The extent and impact of water fluoride outside these regions therefore remain unclear. The current study evaluated fluoride levels in household water sources in Bondo-Rarieda Area in the Kenyan part of the Lake Victoria Basin (LVB) and highlighted the risk posed by water fluoride to the resident communities. The results, it was anticipated, will contribute to in-depth understanding of the fluoride problem in the region. Methods A total of 128 water samples were collected from different water sources from the entire study area and analyzed for fluoride content using ion-selective electrodes. Results Lake Victoria was the main water source in the area but dams and open pans (39.5%), boreholes and shallow wells (23.5%), and streams (18.5%) were the principal water sources outside walking distances from the lake. The overall mean fluoride content of the water exceeded recommended limits for drinking water. The mean water fluoride was highest in Uyoma (1.39±0.84 ppm), Nyang’oma (1.00±0.59 ppm) and Asembo (0.92±0.46 ppm) and lowest in Maranda Division (0.69±0.42 ppm). Ponds (1.41±0.82 ppm), springs (1.25±0.43 ppm), dams and open pans (0.96±0.79 ppm), and streams (0.95±0.41 ppm) had highest fluoride levels but lake and river water did not have elevated fluoride levels. Groundwater fluoride decreased with increasing distance from the lake indicating that water fluoride may have hydro-geologically been translocated into the region from geochemical sources outside the area. Conclusions Lake Victoria was the main water source for the residents of Bondo-Rarieda Area. Majority of in-land residents however used water from dams, open pans, boreholes, shallow wells, ponds and streams, which was generally saline and fluoridated. It was estimated that 36% of children living in this area, who consume water from ground sources from the area could be at the risk of dental fluorosis. PMID:24884434

Effect of guar gum and salt concentrations on drag reduction and shear degradation properties of turbulent flow of water in a pipe.

PubMed

Sokhal, Kamaljit Singh; Gangacharyulu, Dasaroju; Bulasara, Vijaya Kumar

2018-02-01

Concentrated solutions of guar gum in water (1000-3000ppm) with and without KCl salt (1000-4000ppm) were injected near the wall for a short period (2.5min) to investigate their effect on drag reduction in turbulent flow of water through a pipe (Re≈17000-45000). Relative to bulk solution, the concentrations of polymer and salt were 50-150ppm and 50-200ppm, respectively. A drag reduction of 71.45% was observed for 3000ppm of biopolymer without salt. Guar gum experienced mechanical degradation under high shear conditions and addition of KCl improved shear stability up to 47% (for Re≈45000). A polymer concentration of 3000ppm and salt concentration of 2000ppm in the injection fluid were found to be optimum for achieving the highest drag reduction with better shear stability. Results indicated that boundary layer injection shows better drag reduction ability than pre-mixed solutions. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Effect of Climate Change on Ozone Depletion through Changes in Stratospheric Water Vapour

NASA Technical Reports Server (NTRS)

Kirk-Davidoff, Daniel B.; Hintsa, Eric J.; Anderson, James G.; Keith, David W.

1999-01-01

Several studies have predicted substantial increases in Arctic ozone depletion due to the stratospheric cooling induced by increasing atmospheric CO2 concentrations. But climate change may additionally influence Arctic ozone depletion through changes in the water vapor cycle. Here we investigate this possibility by combining predictions of tropical tropopause temperatures from a general circulation model with results from a one-dimensional radiative convective model, recent progress in understanding the stratospheric water vapor budget, modelling of heterogeneous reaction rates and the results of a general circulation model on the radiative effect of increased water vapor. Whereas most of the stratosphere will cool as greenhouse-gas concentrations increase, the tropical tropopause may become warmer, resulting in an increase of the mean saturation mixing ratio of water vapor and hence an increased transport of water vapor from the troposphere to the stratosphere. Stratospheric water vapor concentration in the polar regions determines both the critical temperature below which heterogeneous reactions on cold aerosols become important (the mechanism driving enhanced ozone depletion) and the temperature of the Arctic vortex itself. Our results indicate that ozone loss in the later winter and spring Arctic vortex depends critically on water vapor variations which are forced by sea surface temperature changes in the tropics. This potentially important effect has not been taken into account in previous scenarios of Arctic ozone loss under climate change conditions.

SSTs, nitrogen fertiliser and stratospheric ozone

NASA Technical Reports Server (NTRS)

Turco, R. P.; Whitten, R. C.; Poppoff, I. G.; Capone, L. A.

1978-01-01

A recently revised model of the stratosphere is used to show that a substantial enhancement in the ozone layer could accompany worldwide SST fleet operations and that water vapor may be an important factor in SST assessments. Revised rate coefficients for various ozone-destroying reactions are employed in calculations which indicate a slight increase in the total content of stratospheric ozone for modest-sized fleets of SSTs flying below about 25 km. It is found that water-vapor chemical reactions can negate in large part the NOx-induced ozone gains computed below 25 km and that increased use of nitrogen fertilizer might also enhance the ozone layer.

Application of Ozone MBBR Process in Refinery Wastewater Treatment

NASA Astrophysics Data System (ADS)

Lin, Wang

2018-01-01

Moving Bed Biofilm Reactor (MBBR) is a kind of sewage treatment technology based on fluidized bed. At the same time, it can also be regarded as an efficient new reactor between active sludge method and the biological membrane method. The application of ozone MBBR process in refinery wastewater treatment is mainly studied. The key point is to design the ozone +MBBR combined process based on MBBR process. The ozone +MBBR process is used to analyze the treatment of concentrated water COD discharged from the refinery wastewater treatment plant. The experimental results show that the average removal rate of COD is 46.0%~67.3% in the treatment of reverse osmosis concentrated water by ozone MBBR process, and the effluent can meet the relevant standard requirements. Compared with the traditional process, the ozone MBBR process is more flexible. The investment of this process is mainly ozone generator, blower and so on. The prices of these items are relatively inexpensive, and these costs can be offset by the excess investment in traditional activated sludge processes. At the same time, ozone MBBR process has obvious advantages in water quality, stability and other aspects.

Ozonation of mutagenic and carcinogenic polyaromatic amines and polyaromatic hydrocarbons in water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burleson, G.R.; Caulfield, M.J.; Pollard, M.

1979-06-01

The Salmonella-microsome assay for mutagenesis was used to determine the effect of ozone on the mutagenesis of selected carcinogens and mutagens in water. Short periods of ozonation were shown to completely inactivate the mutagenicity of several polyaromatic amine mutagens including acriflavine, proflavine, and beta-naphthylamine. Selected polyaromatic hydrocarbons were also sensitive to ozonation. Kinetic studies revealed that the mutagenicity of benzo(a)pyrene, 3-methylcholanthrene, and 7,12-dimethylbenz(a)anthracene was destroyed after short periods of ozonation. To correlate loss of mutagenicity with loss of carcinogenicity, two polyaromatic hydrocarbons were treated with ozone, extracted from water with hexane, and tested for carcinogenicity in mice. When 7,12-dimethyl-benz(a)anthracene andmore » 3-methyl-cholanthrene were treated with ozone, there was a substantial reduction in carcinogenicity compared to control groups treated with oxygen alone. However, a small number of tumors developed in the group of animals receiving a hexane extract of ozonated 7,12-dimethylbenz(a)anthracene. This activity may be due to breakdown products of 7,12-dimethylbenz(a)anthracene that are not mutagenic.« less

76 FR 13289 - Approval of One-Year Extension for Attaining the 1997 8-Hour Ozone Standard in the Baltimore...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-11

...). This extension is based on the air quality data for the 4th highest daily 8-hour monitored value during... first one-year extension, the area's 4th highest daily 8-hour average in the attainment year is 0.084 parts per million (ppm) or less. (b) For the second one-year extension, the area's 4th highest daily 8...

Approach for detecting mutagenicity of biodegraded and ozonated pharmaceuticals, metabolites and transformation products from a drinking water perspective.

PubMed

Gartiser, Stefan; Hafner, Christoph; Kronenberger-Schäfer, Kerstin; Happel, Oliver; Trautwein, Christoph; Kümmerer, Klaus

2012-09-01

Many pharmaceuticals and related metabolites are not efficiently removed in sewage treatment plants and enter into surface water. There, they might be subject of drinking water abstraction and treatment by ozonation. In this study, a systematic approach for producing and effect-based testing of transformation products (TPs) during the drinking water ozonation process is proposed. For this, two pharmaceutical parent substances, three metabolites and one environmental degradation product were investigated with respect to their biodegradability and fate during drinking water ozonation. The Ames test (TA98, TA100) was used for the identification of mutagenic activity present in the solutions after testing inherent biodegradability and/or after ozonation of the samples. Suspicious results were complemented with the umu test. Due to the low substrate concentration required for ozonation, all ozonated samples were concentrated via solid phase extraction (SPE) before performing the Ames test. With the exception of piracetam, all substances were only incompletely biodegradable, suggesting the formation of stable TPs. Metformin, piracetam and guanylurea could not be removed completely by the ozonation process. We received some evidence that technical TPs are formed by ozonation of metformin and piracetam, whereas all tested metabolites were not detectable by analytical means after ozonation. In the case of guanylurea, one ozonation TP was identified by LC/MS. None of the experiments showed an increase of mutagenic effects in the Ames test. However, the SPE concentration procedure might lead to false-positive results due to the generation of mutagenic artefacts or might lead to false-negative results by missing adequate recovery efficiency. Thus, these investigations should always be accompanied by process blank controls that are carried out along the whole ozonation and SPE procedure. The study presented here is a first attempt to investigate the significance of transformation products by a systematic approach. However, the adequacy and sensitivity of the methodology need to be further investigated. The approach of combining biodegradation and ozonation with effect-based assays is a promising tool for the early detection of potential hazards from TPs as drinking water contaminants. It can support the strategy for the evaluation of substances and metabolites in drinking water. A multitude of possible factors which influence the results have to be carefully considered, among them the selectivity and sensibility of the mutagenicity test applied, the extraction method for concentrating the relevant compounds and the biocompatibility of the solvent. Therefore, the results have to be carefully interpreted, and possible false-negative and false-positive results should be considered.

Polar stratospheric clouds and ozone depletion

NASA Technical Reports Server (NTRS)

Toon, Owen B.; Turco, Richard P.

1991-01-01

A review is presented of investigations into the correlation between the depletion of ozone and the formation of polar stratospheric clouds (PSCs). Satellite measurements from Nimbus 7 showed that over the years the depletion from austral spring to austral spring has generally worsened. Approximately 70 percent of the ozone above Antarctica, which equals about 3 percent of the earth's ozone, is lost during September and October. Various hypotheses for ozone depletion are discussed including the theory suggesting that chlorine compounds might be responsible for the ozone hole, whereby chlorine enters the atmosphere as a component of chlorofluorocarbons produced by humans. The three types of PSCs, nitric acid trihydrate, slowly cooling water-ice, and rapidly cooling water-ice clouds act as important components of the Antarctic ozone depletion. It is indicated that destruction of the ozone will be more severe each year for the next few decades, leading to a doubling in area of the Antarctic ozone hole.

Impact of ozonation on naphthenic acids speciation and toxicity of oil sands process-affected water to Vibrio fischeri and mammalian immune system.

PubMed

Wang, Nan; Chelme-Ayala, Pamela; Perez-Estrada, Leonidas; Garcia-Garcia, Erick; Pun, Jonathan; Martin, Jonathan W; Belosevic, Miodrag; Gamal El-Din, Mohamed

2013-06-18

Oil sands process-affected water (OSPW) is the water contained in tailings impoundment structures in oil sands operations. There are concerns about the environmental impacts of the release of OSPW because of its toxicity. In this study, ozonation followed by biodegradation was used to remediate OSPW. The impacts of the ozone process evolution on the naphthenic acids (NAs) speciation and acute toxicity were evaluated. Ion-mobility spectrometry (IMS) was used to preliminarily separate isomeric and homologous species. The results showed limited effects of the ozone reactor size on the treatment performance in terms of contaminant removal. In terms of NAs speciation, high reactivity of NAs with higher number of carbons and rings was only observed in a region of high reactivity (i.e., utilized ozone dose lower than 50 mg/L). It was also found that nearly 0.5 mg/L total NAs was oxidized per mg/L of utilized ozone dose, at utilized ozone doses lower than 50 mg/L. IMS showed that ozonation was able to degrade NAs, oxidized NAs, and sulfur/nitrogenated NAs. Complete removal of toxicity toward Vibrio fischeri was achieved after ozonation followed by 28-day biodegradation period. In vitro and in vivo assays indicated that ozonation reduced the OSPW toxicity to mice.

Inactivation characteristics of ozone and electrolysis process for ballast water treatment using B. subtilis spores as a probe.

PubMed

Jung, Youmi; Yoon, Yeojoon; Hong, Eunkyung; Kwon, Minhwan; Kang, Joon-Wun

2013-07-15

Since ballast water affects the ocean ecosystem, the International Maritime Organization (IMO) sets a standard for ballast water management and might impose much tighter regulations in the future. The aim of this study is to evaluate the inactivation efficiency of ozonation, electrolysis, and an ozonation-electrolysis combined process, using B. subtilis spores. In seawater ozonation, HOBr is the key active substance for inactivation, because of rapid reactivity of ozone with Br(-) in seawater. In seawater electrolysis, it is also HOBr, but not HOCl, because of the rapid reaction of HOCl with Br(-), which has not been recognized carefully, even though many electrolysis technologies have been approved by the IMO. Inactivation pattern was different in ozonation and electrolysis, which has some limitations with the tailing or lag-phase, respectively. However, each deficiency can be overcome with a combined process, which is most effective as a sequential application of ozonation followed by electrolysis. Copyright © 2013 Elsevier Ltd. All rights reserved.

A modeling analysis of alternative primary and secondary US ozone standards in urban and rural areas

NASA Astrophysics Data System (ADS)

Nopmongcol, Uarporn; Emery, Chris; Sakulyanontvittaya, Tanarit; Jung, Jaegun; Knipping, Eladio; Yarwood, Greg

2014-12-01

This study employed the High-Order Decoupled Direct Method (HDDM) of sensitivity analysis in a photochemical grid model to determine US anthropogenic emissions reductions required from 2006 levels to meet alternative US primary (health-based) and secondary (welfare-based) ozone (O3) standards. Applying the modeling techniques developed by Yarwood et al. (2013), we specifically evaluated sector-wide emission reductions needed to meet primary standards in the range of 60-75 ppb, and secondary standards in the range of 7-15 ppm-h, in 22 cities and at 20 rural sites across the US for NOx-only, combined NOx and VOC, and VOC-only scenarios. Site-specific model biases were taken into account by applying adjustment factors separately for the primary and secondary standard metrics, analogous to the US Environmental Protection Agency's (EPA) relative response factor technique. Both bias-adjusted and unadjusted results are presented and analyzed. We found that the secondary metric does not necessarily respond to emission reductions the same way the primary metric does, indicating sensitivity to their different forms. Combined NOx and VOC reductions are most effective for cities, whereas NOx-only reductions are sufficient at rural sites. Most cities we examined require more than 50% US anthropogenic emission reductions from 2006 levels to meet the current primary 75 ppb US standard and secondary 15 ppm-h target. Most rural sites require less than 20% reductions to meet the primary 75 ppb standard and less than 40% reductions to meet the secondary 15 ppm-h target. Whether the primary standard is protective of the secondary standard depends on the combination of alternative standard levels. Our modeling suggests that the current 75 ppb standard achieves a 15 ppm-h secondary target in most (17 of 22) cities, but only half of the rural sites; the inability for several western cities and rural areas to achieve the seasonally-summed secondary 15 ppm-h target while meeting the 75 ppb primary target is likely driven by higher background O3 that is commonly reported in the western US. However, a 70 ppb primary standard is protective of a 15 ppm-h secondary standard in all cities and 18 of 20 rural sites we examined, and a 60 ppb primary standard is protective of a 7 ppm-h secondary standard in all cities and 19 of 20 rural sites. If EPA promulgates separate primary and secondary standards, exceedance areas will need to develop and demonstrate control strategies to achieve both. This HDDM analysis provides an illustrative screening assessment by which to estimate emissions reductions necessary to satisfy both standards.

NTP Toxicology and Carcinogenesis Studies of Barium Chloride Dihydrate (CAS No. 10326-27-9) in F344/N Rats and B6C3F1 Mice (Drinking Water Studies).

PubMed

1994-01-01

Barium chloride dihydrate, a white crystalline granule or powder, is used in pigments, aluminum refining, leather tanning and coloring, the manufacture of magnesium metal, ceramics, glass, and paper products, as a pesticide, and in medicine as a cardiac stimulant. Toxicology and carcinogenicity studies were conducted by administering barium chloride dihydrate (99% pure) in drinking water to F344/N rats and B6C3F1 mice for 15 days, 13 weeks, and 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, cultured Chinese hamster ovary cells, and mouse lymphoma cells. 15-DAY STUDY IN RATS: Groups of five males and five females received barium chloride dihydrate in the drinking water at concentrations of 0, 125, 250, 500, 1,000, or 2,000 ppm for 15 days, corresponding to average daily doses of 10, 15, 35, 60, or 110 mg barium/kg body weight to males and females. No chemical-related deaths, differences in final mean body weights, or clinical findings of toxicity were observed. Water consumption by male and female rats exposed to 2,000 ppm was slightly less (S16%) than controls during week 2. There were no significant differences in absolute or relative organ weights between exposed and control rats. No biologically significant differences in hematology, clinical chemistry, or neurobehavioral parameters occurred in rats. 15-DAY STUDY IN MICE: Groups of five males and five females received barium chloride dihydrate in the drinking water at concentrations of 0, 40, 80,173, 346, or 692 ppm for 15 days, corresponding to average daily doses of 5,10, 20, 40, or 70 mg barium/kg body weight to males and 5, 10, 15, 40, or 85 mg barium/kg body weight to females. No chemical-related deaths, differences in mean body weights or in water consumption, or clinical findings of toxicity were observed in mice. The relative liver weight of males receiving 692 ppm was significantly greater than that of the controls. The absolute and relative liver weights of females that received 692 ppm were significantly greater than those of the controls. No histopathologic evidence of toxicity was observed in mice. 13-WEEK STUDY IN RATS: Groups of 10 males and 10 females received barium chloride dihydrate in the drinking water at concentrations of 0, 125, 500, 1,000, 2,000, or 4,000 ppm for 13 weeks, corresponding to average daily doses of 10, 30, 65, 110, or 200 mg barium/kg body weight to males and 10, 35, 65, 115, or 180 mg barium/kg body weight to females. Three males and one female in the 4,000 ppm groups died during the last week of the study. The final mean body weights of male and female rats receiving 4,000 ppm were significantly lower (13% and 8%) than those of the controls. Water consumption by male and female rats in the 4,000 ppm groups was approximately 30% lower than that by the controls. No clearly chemical-related clinical findings of toxicity or neurobehavioral or cardiovascular effects were noted. Serum phosphorus levels in 2,000 and 4,000 ppm male and female rats were significantly higher than those in controls, but there were no biologically significant differences in hematology parameters or in serum sodium, potassium, or calcium levels. Renal tubule dilatation in the outer stripe of the outer medulla and cortex occurred in male and female rats receiving 4,000 ppm. 13-WEEK STUDY IN MICE: Groups of 10 males and 10 females received barium chloride dihydrate in the drinking water at concentrations of 0, 125, 500, 1,000, 2,000, or 4,000 ppm for 13 weeks, corresponding to average daily doses of 15, 55, 100, 205, or 450 mg barium/kg body weight to males and 15, 60, 110, 200, or 495 mg barium/kg body weight to females. Six males and seven females that received 4,000 ppm and one male that received 125 ppm died during the study. Final mean body weights of male and female mice receiving 4,000 ppm were significantly lower (>30%) than those of controls. Water consumption by male mice in the 4,000 ppm group was 18% lower than that by the controls; water consumption by other exposed groups of male and female mice was similar to thatd groups of male and female mice was similar to that by the controls. Clinical findings of toxicity were limited to debilitation in the surviving male and female mice receiving 4,000 ppm. The absolute and/or relative liver weights of mice receiving 1,000, 2,000, and 4,000 ppm were significantly lower than those of the controls. Multifocal to diffuse nephropathy characterized by tubule dilatation, regeneration, and atrophy occurred in 4,000 ppm male and female mice. 2-YEAR STUDY IN RATS: Groups of 60 males and 60 females received barium chloride dihydrate in the drinking water at concentrations of 0, 500, 1,250, or 2,500 ppm for 104 (males) or 105 weeks (females), corresponding to average daily doses of 15, 30, or 60 mg barium/kg body weight for males and 15, 45, or 75 mg barium/kg body weight for females. The high dose of 2,500 ppm was selected based on decreased final mean body weights, mortality, decreased water consumption, and chemical-related kidney lesions observed in the 4,000 ppm groups in the 13-week study. Survival, Body Weights, Water Consumption, and Clinical Findings: Two-year survival of exposed male and female rats was similar to that of the controls. The final mean body weights of male and female rats that received 2,500 ppm were (5% and 11%) lower than those of controls. Beginning as early as week 5, water consumption by male and female rats receiving 2,500 ppm was substantially lower than that by controls (male: 11% to 30%; female: 19% to 33%). There were no chemical-related clinical findings. Hematology and Clinical Chemistry: There were no chemical-related differences in hematology or clinical chemistry parameters in male or female rats. Special Studies: At the 15-month interim evaluation, the plasma barium concentrations (mg/ml) were significantly increased in males receiving 1,250 and 2,500 ppm and in all exposed groups of females (male: 0 ppm, 0.98; 500 ppm, 1.00; 1,250 ppm, 1.23; 2,500 ppm, 1.68; female: 0 ppm, 0.74; 500 ppm, 0.99; 1,250 ppm, 0.97; 2,500 ppm, 1.43). Barium levels in bone in rats from the 2,500 ppm groups were about 400 times greater than those in the controls. Pathology Findings: At the end of 2 years, there were no increased incidences of neoplasms or nonneoplastic lesions that could be attributed to barium chloride dihydrate. However, there were dose-related decreased incidences of adrenal medulla pheochromocytomas and mononuclear cell leukemia in male rats. 2-YEAR STUDY IN MICE: Groups of 60 males and 60 females received barium chloride dihydrate in the drinking water at concentrations of 0, 500, 1,250, or 2,500 ppm for 103 (males) or 104 weeks (females), corresponding to average daily doses of 30, 75, or 160 mg barium/kg body weight for males and 40, 90, or 200 mg barium/kg body weight for females. The high dose of 2,500 ppm was selected based on decreased final mean body weights, mortality, decreased water consumption, and chemical-related kidney lesions observed in the 4,000 ppm groups in the 13-week study. Survival, Body Weights, Water Consumption, and Clinical Findings: Two-year survival of male and female mice receiving 2,500 ppm was significantly lower than that of the controls due to renal toxicity. Final mean body weights of 2,500 ppm males and females were 9% and 12% lower than those of controls. Water consumption by male and female mice receiving barium chloride was similar to that by the controls. There were no chemical-related clinical findings. Hematology and Clinical Chemistry: There were no differences in hematology or clinical chemistry parameters measured at the 15-month interim evaluation. Special Studies: At the 15-month interim evaluation, plasma barium concentrations (mg/mL) were significantly increased in all exposed groups of mice (male: 0 ppm, 0.62; 500 ppm, 0.77; 1,250 ppm, 0.89; 2,500 ppm, 1.49; female: 0 ppm, 0.52; 500 ppm, 0.74; 1,250 ppm, 1.01; 2,500 ppm, 1.35). Pathology Findings: At the end of the 2-year study, there were increased incidences of nephropathy in male and female mice (male: 1/50, 0/50, 2/48, 19/50; female: 0/50, 2/53, 1/50, 37/54). There were no chemical-related increased incidences of neoplasms in male or female mice. The incidence of hepatocellular adenoma was significantly decreased in male mice receiving 2,500 ppm. GENETIC TOXICOLOGY: Barium chloride dihydrate was not mutagenic in Salmonella typhimurium strains TA97, TA98, TA100, TA1535, or TA1537, with or without exogenous metabolic activation (S9). It was mutagenic in L5178Y mouse lymphoma cells in the presence of S9, but it did not induce sister chromatid exchanges or chromosomal aberrations in cultured Chinese hamster ovary cells, with or without S9. CONCLUSIONS: Under the conditions of these 2-year drinking water studies, there was no evidence of carcinogenic activity of barium chloride dihydrate in male or female F344/N rats that received 500, 1,250, or 2,500 ppm. There was no evidence of carcinogenic activity of barium chloride dihydrate in male or female B6C3F1 mice that received 500, 1,250, or 2,500 ppm. There were chemical-related increased incidences of nephropathy in male and female mice.

Ozone and photocatalytic processes to remove the antibiotic sulfamethoxazole from water.

PubMed

Beltrán, Fernando J; Aguinaco, Almudena; García-Araya, Juan F; Oropesa, Ana

2008-08-01

In this study, water containing the pharmaceutical compound sulfamethoxazole (SMT) was subjected to the various treatments of different oxidation processes involving ozonation, and photolysis and catalysis under different experimental conditions. Removal rates of SMT and total organic carbon (TOC), from experiments of simple UVA radiation, ozonation (O(3)), catalytic ozonation (O(3)/TiO(2)), ozone photolysis (O(3)/UVA), photocatalytic oxidation (O(2)/TiO(2)/UVA) and photocatalytic ozonation (O(3)/UVA/TiO(2)), have been compared. Photocatalytic ozonation leads to the highest SMT removal rate (pH 7 in buffered systems, complete removal is achieved in less than 5min) and total organic carbon (in unbuffered systems, with initial pH=4, 93% TOC removal is reached). Also, lowest ozone consumption per TOC removed and toxicity was achieved with the O(3)/UVA/TiO(2) process. Direct ozone and free radical reactions were found to be the principal mechanisms for SMT and TOC removal, respectively. In photocatalytic ozonation, with buffered (pH 7) aqueous solutions phosphates (buffering salts) and accumulation of bicarbonate scavengers inhibit the reactions completely on the TiO(2) surface. As a consequence, TOC removal diminishes. In all cases, hydrogen peroxide plays a key role in TOC mineralization. According to the results obtained in this work the use of photocatalytic ozonation is recommended to achieve a high mineralization degree of water containing SMT type compounds.

Ozone processing of foods and beverages

USDA-ARS?s Scientific Manuscript database

Ozone has a long history of use as a disinfectant in food and beverage processing. In the United States, the application of ozone to disinfect bottled water was approved as Generally Recognized As Safe (GRAS) in 1982. Later it was approved as a sanitizing agent for bottled water treatment lines. Ozo...

Quantitative water quality with LANDSAT and Skylab

NASA Technical Reports Server (NTRS)

Yarger, H. L.; Mccauley, J. R.

1975-01-01

Correlation studies were completed between LANDSAT Multispectral Scanner (MSS) band ratios derived from computer compatible tape (CCT) and 170 water samples taken from three large Kansas reservoirs, coincident with 16 different LANDSAT passes over a 13 month period. The following conclusions were obtained: (1) LANDSAT MSS reflectance levels are useful for quantitative measurement of suspended solids up to at least 900 ppm, (2) MSS band ratios derived from CCT can measure suspended solids with 67% confidence level accuracy of 12 ppm over the range 0-80 ppm and 35 ppm over the range 0900 ppm, (3) suspended solids contour maps can be easily constructed from CCT for water bodies larger than approximately 100 acres, (4) rationing suppresses MSS reflectance level dependence on seasonal sun angle variation and permits measurement of suspended load the year round in the middle latitudes. SKYLAB imagery from a single pass over three reservoirs compares favorably to LANDSAT results up to 100 ppm.

Pulmonary sensitivity to ozone exposure in sedentary versus chronically trained, female rats.

PubMed

Gordon, Christopher J; Phillips, Pamela M; Beasley, Tracey E; Ledbetter, A; Aydin, Cenk; Snow, Samantha J; Kodavanti, Urmila P; Johnstone, Andrew F

2016-06-01

Epidemiological data suggest that a sedentary lifestyle may contribute to increased susceptibility for some environmental toxicants. We developed an animal model of active versus sedentary life style by providing female Sprague-Dawley rats with continuous access to running wheels. Sedentary rats were housed in standard cages without wheels. After training for 12 wks, rats were exposed to 0, 0.25, 0.5 or 1.0 ppm ozone [O3 for 5 h/d, 1 d/wk, for 6 wk (N = 10 per group)]. Body composition (%fat, lean and fluid) was monitored noninvasively over the course of the study. Ventilatory parameters [tidal volume, minute ventilation, frequency and enhanced pause (Penh)] were assessed using whole-body plethysmography prior to O3 and 24 h after the 5th O3 exposure. Trained rats lost ∼2% body fat after 12 wk of access to running wheels. Peak wheel activity was reduced by 40% after exposure to 1.0 ppm O3. After the 5th O3 exposure, body weight and %fat were reduced in sedentary but not trained rats. Penh was significantly elevated in sedentary but not trained rats the day after exposure to 1.0 ppm O3. However, lung lavage cell counts and biomarkers of pulmonary inflammation measured 1 day after the final exposure were inconsistently affected by training. Wheel running led to marked physiological responses along with some indication of improved pulmonary recovery from O3 exposure. However, wheel running with O3 exposure may also be a detriment for some pulmonary endpoints. Overall, a sedentary lifestyle may increase susceptibility to O3, but additional studies are needed.

Research on the influence of ozone dissolved in the fuel-water emulsion on the parameters of the CI engine

NASA Astrophysics Data System (ADS)

Wojs, M. K.; Orliński, P.; Kamela, W.; Kruczyński, P.

2016-09-01

The article presents the results of empirical research on the impact of ozone dissolved in fuel-water emulsion on combustion process and concentration of toxic substances in CI engine. The effect of ozone presence in the emulsion and its influence on main engine characteristics (power, torque, fuel consumption) and selected parameters that characterize combustion process (levels of pressures and temperatures in combustion chamber, period of combustion delay, heat release rate, fuel burnt rate) is shown. The change in concentration of toxic components in exhausts gases when engine is fueled with ozonized emulsion was also identified. The empirical research and their analysis showed significant differences in the combustion process when fuel-water emulsion containing ozone was used. These differences include: increased power and efficiency of the engine that are accompanied by reduction in time of combustion delay and beneficial effects of ozone on HC, PM, CO and NOX emissions.

Laboratory observations of biocide efficiency against Legionella in model cooling tower systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thomas, W.M.; Eccles, J.; Fricker, C.

1999-07-01

The efficacy of specific oxidizing and non-oxidizing biocides was examined using a model cooling system inoculated with a microcosm containing an environmental isolate of Legionella pneumophila. The microcosm was prepared in a two-stage chemostat, which provided a consistent source of microbiological inoculum for the study. The microcosm consisted of both sessile (within biofilms) and planktonic Legionella in association with other microorganisms, including Pseudomonas species and cyst-forming ameobae. A procedure was established to successfully transfer the chemostat grown inoculum to the model cooling system and establish both sessile and planktonic forms of Legionella in the model cooling system. The greatest biocidalmore » effect for all of the biocides was observed immediately after dosing. This effect was relatively short-lived even for the slow acting biocides such isothiazolin (as 8 ppm active) where an effect was only observed over the first 12 hours. The faster acting biocides, DBNPA (as 8 ppm active) and gluteraldehyde (as 27 ppm active), did initially reduce Legionella populations but did not totally eliminate Legionella or provide lasting control. Chlorine and bromine (as 0.5--1.5 ppm free halogen), and ozone (as 0.1--0.5 ppm free reserve) reduced and controlled Legionella populations so long as a free reserve of oxidant was maintained. Legionella recovered quickly after biocide dosing, reestablishing similar levels to those observed before dosing.« less

The Effect of Intermittent Noise Stress on Ozone-Induced ...

EPA Pesticide Factsheets

Previous studies have established that acute exposure to air pollution increases the risk of cardiovascular dysfunction. Intrinsic factors are likely the most important determinants of how the body responds to an exposure. But data also suggests that non-environmental stressors like noise, which is a common urban public health problem, can modify and indeed worsen the response. Noise can cause obvious psychological disturbances typical of non-specific stress, but also changes that can increase the number of cardiovascular disease related mortalities. Therefore, we hypothesized that short-term exposure to noise would worsen the cardiovascular response to ozone. Male Wistar-Kyoto rats were implanted with radiotelemeters for the measurement of heart rate (HR), blood pressure (BP) and electrocardiogram (ECG) and exposed to intermittent noise (85-90 dB) for one week after which they were exposed to either ozone (0.8 ppm) or filtered air. Left ventricular functional responses to dobutamine were measured using a Millar probe as well as arrhythmic sensitivity to aconitine in a separate set of untelemetered rats 24 hours after exposure. HR and BP decreased in all telemetered animals during ozone exposure; noise caused BP and HR to increase. Baseline left ventricular pressure (LVP) was significantly higher in animals exposed to both noise and ozone when compared to no noise; furthermore those animals had the least amount of change in LVP, dP/dT max and min with increasi

Comparison of pharmaceutical abatement in various water matrices by conventional ozonation, peroxone (O3/H2O2), and an electro-peroxone process.

PubMed

Wang, Huijiao; Zhan, Juhong; Yao, Weikun; Wang, Bin; Deng, Shubo; Huang, Jun; Yu, Gang; Wang, Yujue

2018-03-01

Pharmaceutical abatement in a groundwater (GW), surface water (SW), and secondary effluent (SE) by conventional ozonation, the conventional peroxone (O 3 /H 2 O 2 ), and the electro-peroxone (E-peroxone) processes was compared in batch tests. SE had significantly more fast-reacting dissolved organic matter (DOM) moieties than GW and SW. Therefore, O 3 decomposed much faster in SE than in GW and SW. At specific ozone doses of 0.5-1.5 mg O 3 /mg dissolved organic carbon (DOC), the application of O 3 /H 2 O 2 and E-peroxone process (by adding external H 2 O 2 stocks or in-situ generating H 2 O 2 from cathodic O 2 reduction during ozonation) similarly enhanced the OH yield from O 3 decomposition by ∼5-12% and 5-7% in GW and SW, respectively, compared to conventional ozonation. In contrast, due to the slower reaction kinetics of O 3 with H 2 O 2 than O 3 with fast-reacting DOM moieties, the addition or electro-generation of H 2 O 2 hardly increased the OH yield (<4% increases) in SE. Corresponding to the changes in the OH yields, the abatement efficiencies of ozone-resistant pharmaceuticals (ibuprofen and clofibric acid) increased evidently in GW (up to ∼14-18% at a specific ozone dose of 1.5 mg O 3 /mg DOC), moderately in SW (up to 6-10% at 0.5 mg O 3 /mg DOC), and negligibly in SE during the O 3 /H 2 O 2 and E-peroxone treatment compared to conventional ozonation. These results indicate that similar to the conventional O 3 /H 2 O 2 process, the E-peroxone process can more pronouncedly enhance O 3 transformation to OH, and thus increase the abatement efficiency of ozone-resistant pharmaceuticals in water matrices exerting relatively high ozone stability (e.g., groundwater and surface water with low DOM contents). Therefore, by installing electrodes in existing ozone reactors, the E-peroxone process may provide a convenient way to enhance pharmaceutical abatement in drinking water applications, where groundwater and surface water with low DOM contents are used as the source waters. Copyright © 2017 Elsevier Ltd. All rights reserved.

Quality of tomato slices disinfected with ozonated water.

PubMed

Aguayo, Encarna; Escalona, Víctor; Silveira, Ana Cecilia; Artés, Francisco

2014-04-01

Fresh-cut industry needs novel disinfectant to replace the use of chlorine. Ozone is one of the most powerful oxidizing agents and is applied in gaseous or aqueous form for sanitation purposes. However, the strong oxidative effect could affect the nutritional and sensorial quality, in particular, when time of washing is extended. For that reason, the overall impact of ozonated water (0.4 mg/L) dipping applied during 1, 3 and 5 min compared to control washed in water during 5 min was studied in tomato slices stored during 14 days at 5 . According to the results, ozonated water treatment of 3 min achieved the best firmness retention, microbial quality (mesophilic, psychrotrophic and yeas load) and reduced the consumption of fructose and glucose. The use of ozonated water did not affect the total acidity, pH, total solid soluble, organic acid as ascorbic, fumaric or succinic acid and the sensorial parameters, which were only affected by storage time. However, the poor appearance, aroma and overall quality obtained in all treatments prevented shelf life of 14 days and the quality at acceptable levels was established in 10 days at 5 . It is recommended to wash tomato slices with 0.4 mg/L ozonated water for 3 min only. Extending treatment duration did not improve the microbiological quality, possibly due to the extra time permitting the ozone to react with other components of the fruit tissue, undermining the antimicrobial benefits.

Reduction in pesticide residue levels in olives by ozonated and tap water treatments and their transfer into olive oil.

PubMed

Kırış, Sevilay; Velioglu, Yakup Sedat

2016-01-01

The effects of different wash times (2 and 5 min) with tap and ozonated water on the removal of nine pesticides from olives and the transfer ratios of these pesticides during olive oil production were determined. The reliability of the analytical methods was also tested. The applied methods of analysis were found to be suitable based on linearity, trueness, repeatability, selectivity and limit of quantification all the pesticides tested. All tap and ozonated water wash cycles removed a significant quantity of the pesticides from the olives, with a few exceptions. Generally, extending the wash time increased the pesticide reduction with ozonated water, but did not make significant differences with tap water. During olive oil processing, depending on the processing technique and physicochemical properties of the pesticides, eight of nine pesticides were concentrated into olive oil (processing factor > 1) with almost no significant difference between treatments. Imidacloprid did not pass into olive oil. Ozonated water wash for 5 min reduced chlorpyrifos, β-cyfluthrin, α-cypermethrin and imidacloprid contents by 38%, 50%, 55% and 61% respectively in olives.

Exposure to air pollution is associated with lung hyperinflation in healthy children and adolescents in Southwest Mexico City: a pilot study.

PubMed

Calderón-Garcidueñas, L; Mora-Tiscareño, A; Chung, C J; Valencia, G; Fordham, L A; García, R; Osnaya, N; Romero, L; Acuña, H; Villarreal-Calderón, A; Devlin, R B; Koren, H S

2000-06-01

Air pollution produces adverse health effects. The consequences of lifelong daily exposures to atmospheric pollutants upon the respiratory apparatus of healthy children are of considerable clinical importance. We investigated the association between exposure to a highly polluted urban environment with a complex mixture of air pollutants-ozone and particulate matter the predominant ones-and chest x-ray abnormalities in 59 healthy Mexican children who are lifelong residents of Southwest Metropolitan Mexico City (SWMMC), with a negative history of tobacco exposure and respiratory illnesses. Their clinical results and x-ray findings were compared to those of 19 Mexican control children, residents of a low-pollution area, with a similar negative history of tobacco exposure and respiratory illnesses. Ozone concentrations in SWMMC exceeded the U.S. Environmental Protection Agency (U.S. EPA) National Ambient Air Quality Standard (NAAQS) for O(3): 0.08 ppm as 1-h maximal concentration, not to be exceeded more than 4 times a year, on 71% of days in 1986 and 95% in 1997, with values as high as 0.48 ppm. Ozone maximal peaks are usually recorded between 2 and 5 pm coinciding with children's outdoor physical activities. Children in the control group reported no upper or lower respiratory symptomatology. Every SWMMC child complained of upper and/or lower respiratory symptoms, including epistaxis, nasal dryness and crusting, cough, shortness of breath, and chest discomfort. Children aged 7-13 yr had the most symptomatology, while 5- to 6-year olds and adolescents with the lowest number of statistically significant outdoor exposure hours had less respiratory symptoms. Bilateral symmetric mild lung hyperinflation was significantly associated with exposure to the SWMMC atmosphere (p = .0004). Chronic and sustained inhalation of a complex mixture of air pollutants, including ozone and particulate matter (PM), is associated with lung hyperinflation, suggestive of small airway disease, in a population of clinically healthy children and adolescents. Small airways are a target of air pollutants in SWMMC children, with ozone and PM being most likely responsible, based on experimental animal, controlled-chamber, and epidemiological data available. Our main concern is the potential likelihood for the development of chronic lung disease in this highly exposed population.

Fluoride Content of Bottled Waters in Hong Kong and Qatar.

PubMed

Al-Mulla, Hessa I; Anthonappa, Robert P; King, Nigel M

2016-01-01

To determine the F concentration of bottled waters that was available in Hong Kong and Qatar. The F concentrations of bottled waters collected from Hong Kong (n=81) and Qatar (n=32) were analysed. The F ion selective electrode method was used to measure the F concentration in the samples. Three measurements were obtained for every sample to ensure reproducibility and appropriate statistical analyses were employed. Qatar group: F concentrations ranged from 0.06 ppm to 3.0 ppm with a mean value of 0.8 ppm. The F concentrations displayed on the labels of the samples (60%) were significantly lower than the measured F concentration (p < 0.0001). Hong Kong group: F concentrations ranged from 0.04 ppm to 2.52 ppm with a mean value of 0.44 ppm. The F concentrations displayed on the samples (16%) were significantly lower than the measured F concentration (p< 0.0001). Wide variations exist in the F concentration among the different brands of bottled water available in Hong Kong and Qatar. The F concentrations displayed on the labels were not consistent with the measured F concentrations.

PLANT WATER STATUS INFLUENCES OZONE SENSITIVITY OF BEAN PLANTS

EPA Science Inventory

Studies were conducted in a controlled environment chamber to determine the association between plant water status and ozone sensitivity. Bean plants were subjected to various water stress regimes for 4 to 10 days using a semipermeable membrane system which controlled plant water...

Water content within the oceanic upper mantle of the Southwest Indian Ridge: a FTIR analysis of orthopyroxenes of abyssal peridotites

NASA Astrophysics Data System (ADS)

Li, W.; Li, H.; Tao, C.; Jin, Z.

2013-12-01

Water can be present in the oceanic upper mantle as structural OH in nominally anhydrous minerals. Such water has marked effects on manlte melting and rheology properties. However, the water content of MORB source is mainly inferred from MORB glass data that the water budget of oceanic upper mantle is poorly constrained. Here we present water analysis of peridotites from different sites on the Southwest Indian Ridge. The mineral assemblages of these peridotites are olivine, orthopyroxene, clinopyroxene and spinel. As the peridotites have been serpentinized to different degrees, only water contents in orthopyroxnene can be better determined by FTIR spectrometry. The IR absorption bands of all measured orthopyroxenes can be devided into four different groups: (1)3562-3596 cm-1, (2)3515-3520 cm-1, (3)3415-3420 cm-1, (4)3200-3210 cm-1. The positions of these absorption bands are in good agreement with perivious reports. Hydrogen profile measurements performed on larger opx grains in each suite of samples show no obvious variations between core and rims regions, indicating that diffusion of H in orthopyroxene is insignificant. Preliminary measured water contents of orthopyroxene differ by up to one order of magnitude. Opx water contents (80-220 ppm) of most samples are within the range of those found in mantle xenoliths of contentinal settings [1]. Opx water contents of one sample (VM-21V-S9-D5-2: 38-64 ppm) are similar to those from Gakkel Ridge abyssal peridotites (25-60 ppm) [2] but higher than those from Mid-Atlantic Ridge ODP-Leg 209(~15 ppm) [3]. Two other samples show high water concentrations (VM-19ΙΙΙ-S3-TVG2-4: 260-275 ppm, Wb-18-b: 190-265 ppm) which compare well with those from Mid-Atlantic Ridge ODP-Leg 153(160-270 ppm) [4]. Most opx water contents decrease with increasing depletion degree (spl Cr#) consistent with an incompatible behavior of water during partial melting. Recalculated bulk water contents (27-117 ppm) of these peridotites overlap estimates for MORB source. However, estimated original bulk water contents prior to partial melting of some samples are very high (e.g. wb-18-b: 540-770 ppm) and can not simply be explained by melt extraction. Our data suggest that the water contents in the oceanic upper mantle of SWIR are heterogeneous or different post-melt depletion histories are involved. Reference [1] Peslier (2010) JVGR 197, 239-258. [2] Peslier et al. (2007) Goldschmidt. [3] Gose et al. (2009) Geology 37,543-546 [4] Schmädicke et al. (2011) Lithos 125, 308-320.

Ozone Sensitivity in Sweet Corn (Zea mays L.) Plants: A Possible Relationship to Water Balance

PubMed Central

Harris, Michael J.; Heath, Robert L.

1981-01-01

Stomatal characteristics affecting gas exchange were compared in two sweet corn hybrids (var. Bonanza and Monarch Advance) which differ in foliar ozone sensitivity. No significant differences were observed in stomatal frequencies, guard cell lengths, or conductances to water vapor diffusion. When plant water status was compared, leaf-water potentials for the ozone-resistant cultivar, Bonanza, were lower. A comparison of the relationship between soil- and leaf-water potential indicated that the leaf-water potential of Bonanza was more sensitive to declines in soil-water potential. Additionally, a comparison of stomatal conductance to water vapor diffusion as soil moisture declined and following root detachment indicated that stomata of Bonanza were, likewise, more sensitive to increasing water stress. Data suggest that these differences are attributable to a greater shoot-to-root fresh weight ratio and higher resistance to water movement in the water-conducting tissues for Bonanza. Our observations suggest that root and water delivery system characteristics play a major contributory role in the determination of foliar ozone sensitivity in this species. PMID:16662019

N-nitrosodimethylamine (NDMA) formation from the ozonation of model compounds.

PubMed

Marti, Erica J; Pisarenko, Aleksey N; Peller, Julie R; Dickenson, Eric R V

2015-04-01

Nitrosamines are a class of toxic disinfection byproducts commonly associated with chloramination, of which several were included on the most recent U.S. EPA Contaminant Candidate List. Nitrosamine formation may be a significant barrier to ozonation in water reuse applications, particularly for direct or indirect potable reuse, since recent studies show direct formation during ozonation of natural water and treated wastewaters. Only a few studies have identified precursors which react with ozone to form N-nitrosodimethylamine (NDMA). In this study, several precursor compound solutions, prepared in ultrapure water and treated wastewater, were subjected to a 10 M excess of ozone. In parallel experiments, the precursor solutions in ultrapure water were exposed to gamma radiation to determine NDMA formation as a byproduct of reactions of precursor compounds with hydroxyl radicals. The results show six new NDMA precursor compounds that have not been previously reported in the literature, including compounds with hydrazone and carbamate moieties. Molar yields in deionized water were 61-78% for 3 precursors, 12-23% for 5 precursors and <4% for 2 precursors. Bromide concentration was important for three compounds (1,1-dimethylhydrazine, acetone dimethylhydrazone and dimethylsulfamide), but did not enhance NDMA formation for the other precursors. NDMA formation due to chloramination was minimal compared to formation due to ozonation, suggesting distinct groups of precursor compounds for these two oxidants. Hydroxyl radical reactions with the precursors will produce NDMA, but formation is much greater in the presence of molecular ozone. Also, hydroxyl radical scavenging during ozonation leads to increased NDMA formation. Molar conversion yields were higher for several precursors in wastewater as compared to deionized water, which could be due to catalyzed reactions with constituents found in wastewater or hydroxyl radical scavenging. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antioxidant activities of nano-bubble hydrogen-dissolved water assessed by ESR and 2,2'-bipyridyl methods.

PubMed

Kato, Shinya; Matsuoka, Daigo; Miwa, Nobuhiko

2015-08-01

We prepared nano-bubble hydrogen-dissolved water (nano-H water) which contained hydrogen nano-bubbles of <717-nm diameter for 54% of total bubbles. In the DMPO-spin trap electron spin resonance (ESR) method, the DMPO-OH:MnO ratio, being attributed to amounts of hydroxyl radicals (OH), was 2.78 for pure water (dissolved hydrogen [DH]≤0.01 ppm, oxidation-reduction potential [ORP]=+324 mV), 2.73 for tap water (0.01 ppm, +286 mV), 2.93 for commercially available hydrogen water (0.075 ppm, +49 mV), and 2.66 for manufactured hydrogen water (0.788 ppm, -614 mV), whereas the nano-H water (0.678 ppm, -644 mV) exhibited 2.05, showing the superiority of nano-H water to other types of hydrogen water in terms of OH-scavenging activity. Then, the reduction activity of nano-H water was assessed spectrophotometrically by the 2,2'-bipyridyl method. Differential absorbance at 530 nm was in the order: 0.018 for pure water, 0.055 for tap water, 0.079 for nano-H water, 0.085 for commercially available hydrogen water, and 0.090 for manufactured hydrogen water, indicating a prominent reduction activity of hydrogen water and nano-H water against oxidation in ascorbate-coupled ferric ion-bipyridyl reaction. Thus, nano-H water has an improved antioxidant activity as compared to hydrogen water of similar DH-level, indicating the more marked importance of nano-bubbles rather than the concentration of hydrogen in terms of OH-scavenging. Copyright © 2015 Elsevier B.V. All rights reserved.

Field-analysis of potable water quality and ozone efficiency in ozone-assisted biological filtration systems for surface water treatment.

PubMed

Zanacic, Enisa; Stavrinides, John; McMartin, Dena W

2016-11-01

Potable water treatment in small communities is challenging due to a complexity of factors starting with generally poor raw water sources, a smaller tax and consumption base that limit capital and operating funds, and culminating in what is typically a less sophisticated and robust water treatment plant for production and delivery of safe, high quality potable water. The design and optimization of modular ozone-assisted biological filtration systems can address some of these challenges. In surface water treatment, the removal of organic matter (e.g., dissolved organic carbon - DOC), inorganic nutrients and other exposure-related contaminants (e.g., turbidity and dissolved solids) from the raw water source is essential. Thus, a combination of chemical and biological oxidation processes can produce an effective and efficient water treatment plant design that is also affordable and robust. To that end, the ozone-assisted biological filtration water treatment plants in two communities were evaluated to determine the efficacy of oxidation and contaminant removal processes. The results of testing for in-field system performance indicate that plant performance is particularly negatively impacted by high alkalinity, high organics loading, and turbidity. Both bicarbonate and carbonate alkalinity were observed to impede ozone contact and interaction with DOC, resulting in lower than anticipated DOC oxidation efficiency and bioavailability. The ozone dosage at both water treatment plants must be calculated on a more routine basis to better reflect both the raw water DOC concentration and presence of alkalinities to ensure maximized organics oxidation and minimization of trihalomethanes production. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

OZONATION BYPRODUCTS: IDENTIFICATION OF BROMOHYDRINS FROM THE OZONATION OF NATURAL WATERS WITH ENHANCED BROMIDE LEVELS

EPA Science Inventory

When ozone is used in the treatment of drinking water, it reacts with both inorganic and organic compounds to form byproducts. f bromide is present, it may be oxidized to hydrobromous acid, which may than react with natural organic matter to form brominated organic compounds. he ...

Comparative evaluation of effects of ozonated and chlorinated thermal discharges on estuarine and fresh water organisms. First quarterly progress report, April 1979

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guerra, C.R.; DelMonaco, J.L.; Singletary, J.H.

1979-01-01

The biological evaluation program incorporates three types of experimental tests: acute (96 hour) toxicity studies; behavioral (avoidance) response studies; and physiological (cough) response studies. In addition, specimens used in testing are examined for physical damage resulting from exposure to chlorine or ozoen. The objective of the acute (96 hour) toxicity study is to determine the respective lethal levels (LC/sub 50/) of chlorinated and ozonated waters. The objective of the behavioral (avoidance) response study is to determine what (if any) concentrations of ozone and of chlorine will be avoided. The objective of physiological (cough) response study is to determine what concentrationsmore » of ozone and of chlorine are physiologically detected. Ozonated and chlorinated waters were evaluated in all studies for both the addition of increased temperature and without it. Results indicate that ozone is less toxic than chlorine under the test conditions used. The lethal levels vary according to species of water quality measurements at Bergen Generating Station, New York are tabulated. (JBG)« less

Editor's Highlight: CCR2 Regulates Inflammatory Cell Accumulation in the Lung and Tissue Injury following Ozone Exposure.

PubMed

Francis, Mary; Groves, Angela M; Sun, Richard; Cervelli, Jessica A; Choi, Hyejeong; Laskin, Jeffrey D; Laskin, Debra L

2017-02-01

Ozone-induced lung injury is associated with an accumulation of activated macrophages in the lung. Chemokine receptor CCR2 mediates the migration of inflammatory monocytes/macrophages to sites of tissue injury. It is also required for monocyte egress from the bone marrow. In the present studies, we analyzed the role of CCR2 in inflammatory cell trafficking to the lung in response to ozone. Treatment of mice with ozone (0.8 ppm, 3 h) resulted in increases in proinflammatory CCR2 + macrophages in the lung at 24 h, as well as proinflammatory CD11b  +  Ly6C Hi and iNOS +  macrophages at 24 and 48 h. Mannose receptor +  anti-inflammatory macrophages were also observed in the lung 24 and 48 h post-ozone. Loss of CCR2 was associated with reduced numbers of proinflammatory macrophages in the lung and decreased expression of the proinflammatory cytokines, IL-1β and TNFα. Decreases in anti-inflammatory CD11b  +  Ly6C Lo macrophages were also observed in lungs of CCR2 -/- mice treated with ozone, whereas mannose receptor +  macrophage accumulation was delayed; conversely, CX3CL1 and CX3CR1 were upregulated. Changes in lung macrophage subpopulations and inflammatory gene expression in CCR2 -/- mice were correlated with reduced ozone toxicity and oxidative stress, as measured by decreases in bronchoalveolar lavage protein content and reduced lung expression of heme-oxygenase-1, 4-hydroxynonenal and cytochrome b5. These data demonstrate that CCR2 plays a role in both pro- and anti-inflammatory macrophage accumulation in the lung following ozone exposure. The fact that ozone-induced lung injury and oxidative stress are reduced in CCR2 -/- mice suggests more prominent effects on proinflammatory macrophages. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Editor’s Highlight: CCR2 Regulates Inflammatory Cell Accumulation in the Lung and Tissue Injury following Ozone Exposure

PubMed Central

Francis, Mary; Groves, Angela M.; Sun, Richard; Cervelli, Jessica A.; Choi, Hyejeong; Laskin, Jeffrey D.; Laskin, Debra L.

2017-01-01

Ozone-induced lung injury is associated with an accumulation of activated macrophages in the lung. Chemokine receptor CCR2 mediates the migration of inflammatory monocytes/macrophages to sites of tissue injury. It is also required for monocyte egress from the bone marrow. In the present studies, we analyzed the role of CCR2 in inflammatory cell trafficking to the lung in response to ozone. Treatment of mice with ozone (0.8 ppm, 3 h) resulted in increases in proinflammatory CCR2+ macrophages in the lung at 24 h, as well as proinflammatory CD11b + Ly6CHi and iNOS+ macrophages at 24 and 48 h. Mannose receptor+ anti-inflammatory macrophages were also observed in the lung 24 and 48 h post-ozone. Loss of CCR2 was associated with reduced numbers of proinflammatory macrophages in the lung and decreased expression of the proinflammatory cytokines, IL-1β and TNFα. Decreases in anti-inflammatory CD11b + Ly6CLo macrophages were also observed in lungs of CCR2−/− mice treated with ozone, whereas mannose receptor+ macrophage accumulation was delayed; conversely, CX3CL1 and CX3CR1 were upregulated. Changes in lung macrophage subpopulations and inflammatory gene expression in CCR2−/− mice were correlated with reduced ozone toxicity and oxidative stress, as measured by decreases in bronchoalveolar lavage protein content and reduced lung expression of heme-oxygenase-1, 4-hydroxynonenal and cytochrome b5. These data demonstrate that CCR2 plays a role in both pro- and anti-inflammatory macrophage accumulation in the lung following ozone exposure. The fact that ozone-induced lung injury and oxidative stress are reduced in CCR2−/− mice suggests more prominent effects on proinflammatory macrophages. PMID:27837169

Ozone exposure during the early postnatal period alters the timing and pattern of alveolar growth and development in nonhuman primates.

PubMed

Avdalovic, Mark V; Tyler, Nancy K; Putney, Lei; Nishio, Susie J; Quesenberry, Sherri; Singh, Parmjit J; Miller, Lisa A; Schelegle, Edward S; Plopper, Charles G; Vu, Thiennu; Hyde, Dallas M

2012-10-01

Exposure to oxidant air pollutants in early childhood, with ozone as the key oxidant, has been linked to significant decrements in pulmonary function in young adults and exacerbation of airway remodeling in asthma. Development of lung parenchyma in rhesus monkeys is rapid during the first 2 years of life (comparable to the first 6 years in humans). Our hypothesis is that ozone inhalation during infancy alters alveolar morphogenesis. We exposed infant rhesus monkeys biweekly to 5, 8 hr/day, cycles of 0.5 ppm ozone with or without house dust mite allergen from 1 to 3 or 1 to 6 months of age. Monkeys were necropsied at 3 and 6 months of age. A morphometric approach was used to quantify changes in alveolar volume and number, the distribution of alveolar size, and capillary surface density per alveolar septa. Quantitative real time PCR was used to measure the relative difference in gene expression over time. Monkeys exposed to ozone alone or ozone combined with allergen had statistically larger alveoli that were less in number at 3 months of age. Alveolar capillary surface density was also decreased in the ozone exposed groups at 3 months of age. At 6 months of age, the alveolar number was similar between treatment groups and was associated with a significant rise in alveolar number from 3 to 6 months of age in the ozone exposed groups. This increase in alveolar number was not associated with any significant increase in microvascular growth as measured by morphometry or changes in angiogenic gene expression. Inhalation of ozone during infancy alters the appearance and timing of alveolar growth and maturation. Understanding the mechanism involved with this altered alveolar growth may provide insight into the parenchymal injury and repair process that is involved with chronic lung diseases such as severe asthma and COPD. Copyright © 2012 Wiley Periodicals, Inc.

Effect of mercury chloride to number of melano-macrophage centers on the kidney of carp fish (Cyprinus carpio)

NASA Astrophysics Data System (ADS)

Mubarokah, L.; Tjahjaningsih, W.; Sulmartiwi, L.

2018-04-01

Mercury chloride can cause immunotoxic effects on fish. The accumulation or aggregate of melano-macrophages centers (MMCs) in the kidney is a feature of cellular immune response, so it can be used as a bioindicator of heavy metal toxicity in waters. This research aims to determine an effect of heavy metal exposure concentration of mercury chloride (HgCl2) on a number of MMCs from common carp kidney. This research using four treatments of mercury chloride: 0 ppm, 0.01 ppm, 0.05 ppm and 0.1 ppm. The main parameters were the number of MMCs in kidney common carp. Supporting parameter was behavior change, water quality and concentration of mercury in the water and kidney. The results of the research showed that the concentration the heavy metal exposure concentration of mercury chloride (HgCl2) affected the number of MMCs from common carp (Cyprinus carpio) kidney. The number of MMCs in the kidney of common carp exposed to mercury chloride 0.01 ppm, 0.05 ppm and 0.1 ppm increased compared to carp was not exposed to mercury chloride (0 ppm).

Induction of glandular stomach cancers in Helicobacter pylori-sensitive Mongolian gerbils treated with N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine in drinking water.

PubMed

Tatematsu, M; Yamamoto, M; Shimizu, N; Yoshikawa, A; Fukami, H; Kaminishi, M; Oohara, T; Sugiyama, A; Ikeno, T

1998-02-01

An animal model of stomach carcinogenesis was established using Mongolian gerbils with N-methyl-N-nitrosourea (MNU) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) as the carcinogens. In addition, the sensitivity of these gerbils to Helicobacter pylori (H. pylori) was confirmed. One hundred and sixty specific pathogen-free male MGS/Sea animals, 7 weeks old, were treated with MNU in the drinking water (30 ppm for alternate weeks to give 10 weeks exposure, or 10 ppm or 3 ppm for 20 weeks continuous exposure), or given MNNG in the drinking water at 400 ppm or 200 ppm for 20 weeks, or orally inoculated with ATCC43504 H. pylori (1.7 x 10(8) CFUs/animal). Adenocarcinomas in the glandular stomach were found in 2 out of 12 effective animals (2/ 12) treated with 30 ppm MNU at week 20, although all were dead or moribund by week 30 due to MNU toxicity. At week 50, the incidences of gastric adenocarcinomas in groups treated with 10 ppm MNU, 3 ppm MNU, 400 ppm MNNG, and 200 ppm MNNG were 2/21 (9.5%), 1/23 (4.3%), 7/ 11 (63.6%), and 1/10 (10.0%). The lesions were generally well differentiated, although poorly differentiated adenocarcinoma was also found in a single gerbil in each of the 10 ppm MNU and 400 ppm MNNG groups. In control animals no tumors were found. In the infection study, the animals were killed at week 20, and H. pylori was detected in all cases, causing multiple erosions with marked inflammatory cell infiltration in the lamina propria and submucosa, and frequent formation of lymphoid follicles. Thus, MNU and MNNG in the drinking water induced neoplastic lesions in the glandular stomach epithelium of H. pylori-sensitive gerbils.

Improving assessments of tropospheric ozone injury to Mediterranean montane conifer forests in California (USA) and Catalonia (Spain) with GIS models related to plant water relations

NASA Astrophysics Data System (ADS)

Kefauver, Shawn C.; Peñuelas, Josep; Ustin, Susan L.

2012-12-01

The impacts of tropospheric ozone on conifer health in the Sierra Nevada of California, USA, and the Pyrenees of Catalonia, Spain, were measured using field assessments and GIS variables of landscape gradients related to plant water relations, stomatal conductance and hence to ozone uptake. Measurements related to ozone injury included visible chlorotic mottling, needle retention, needle length, and crown depth, which together compose the Ozone Injury Index (OII). The OII values observed in Catalonia were similar to those in California, but OII alone correlated poorly to ambient ozone in all sites. Combining ambient ozone with GIS variables related to landscape variability of plant hydrological status, derived from stepwise regressions, produced models with R2 = 0.35, p = 0.016 in Catalonia, R2 = 0.36, p < 0.001 in Yosemite and R2 = 0.33, p = 0.007 in Sequoia/Kings Canyon National Parks in California. Individual OII components in Catalonia were modeled with improved success compared to the original full OII, in particular visible chlorotic mottling (R2 = 0.60, p < 0.001). The results show that ozone is negatively impacting forest health in California and Catalonia and also that modeling ozone injury improves by including GIS variables related to plant water relations.

Application of ozone micro-nano-bubbles to groundwater remediation.

PubMed

Hu, Liming; Xia, Zhiran

2018-01-15

Ozone is widely used for water treatment because of its strong oxidation ability. However, the efficiency of ozone in groundwater remediation is limited because of its relatively low solubility and rapid decomposition in the aqueous phase. Methods for increasing the stability of ozone within the subsurface are drawing increasing attention. Micro-nano-bubbles (MNBs), with diameters ranging from tens of nanometres to tens of micrometres, present rapid mass transfer rates, persist for a relatively long time in water, and transport with groundwater flow, which significantly improve gas concentration and provide a continuous gas supply. Therefore, MNBs show a considerable potential for application in groundwater remediation. In this study, the characteristics of ozone MNBs were examined, including their size distribution, bubble quantity, and zeta potential. The mass transfer rate of ozone MNBs was experimentally investigated. Ozone MNBs were then used to treat organics-contaminated water, and they showed remarkable cleanup efficiency. Column tests were also conducted to study the efficiency of ozone MNBs for organics-contaminated groundwater remediation. Based on the laboratory tests, field monitoring was conducted on a trichloroethylene (TCE)-contaminated site. The results showed that ozone MNBs can greatly improve remediation efficiency and represent an innovative technology for in situ remediation of organics-contaminated groundwater. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Diclofenac removal from water with ozone and activated carbon.

PubMed

Beltrán, Fernando J; Pocostales, Pablo; Alvarez, Pedro; Oropesa, Ana

2009-04-30

Diclofenac (DCF) has been treated in water with ozone in the presence of various activated carbons. Activated carbon-free ozonation or single ozonation leads to a complete degradation of DCF in less than 15 min while in the presence of activated carbons higher degradation rates of TOC and DCF are noticeably achieved. Among the activated carbons used, P110 Hydraffin was found the most suitable for the catalytic ozonation of DCF. The influence of pH was also investigated. In the case of the single ozonation the increasing pH slightly increases the TOC removal rate. This effect, however, was not so clear in the presence of activated carbons where the influence of the adsorption process must be considered. Ecotoxicity experiments were performed, pointing out that single ozonation reduces the toxicity of the contaminated water but catalytic ozonation improved those results. As far as kinetics is concerned, DCF is removed with ozone in a fast kinetic regime and activated carbon merely acts as a simple adsorbent. However, for TOC removal the ozonation kinetic regime becomes slow. In the absence of the adsorbent, the apparent rate constant of the mineralization process was determined at different pH values. On the other hand, determination of the rate constant of the catalytic reaction over the activated carbon was not possible due to the effect of mass transfer resistances that controlled the process rate at the conditions investigated.

EVALUATION OF OZONATION BY-PRODUCTS FROM TWO CALIFORNIA SURFACE WATERS

EPA Science Inventory

Ozonation by-products were analyzed for two surface water sources in Southern California--Los Angeles Aqueduct Water (LAAW) and State Project Water (SPW). ncluded are data obtained when LAAW was being treated at the Los Angeles Aqueduct Filtration Plant and similar data obtained ...

EVALUATION OF OZONATION BY-PRODUCTS FROM TWO CALIFORNIA SURFACE WATERS

EPA Science Inventory

Ozonation by-products were analyzed for two surface water sources in Southern California-Los Angeles Aqueduct Water (LAWW) and State Project Water (SPW). Included are data obtained when LAAW was being treated at the Los Angeles Aqueduct Filtration Plant and similar data obtained...

Metal cycling along the northwestern Seward Peninsula, Alaska: A possible natural cause of metal contamination in the arctic: A section in Geologic studies in Alaska by the U.S. Geological Survey, 1997

USGS Publications Warehouse

Parnow, C.C.; Goldfarb, Richard J.; Kelley, Karen D.; York, Geoffrey S.

1999-01-01

The northwestern Seward Peninsula was targeted for detailed geochemical study after evaluation of data collected during the NURE reconnaissance-level program indicated anomalously high arsenic (60-635 ppm) concentrations in stream sediments. The arsenic is associated with tin skarn, greisen, and replacement deposits in the western Seward Peninsula. Surficial sampling of waters and sediments indicate that arsenic is being transported detritally but that solution transport is insignificant. Our new data indicate that sediments downstream from these tin occurrences are characterized by anomalous values of As (85- 530 ppm) and Sn (14-36 ppm), as well as consistent anomalies of Ag, Be, Cu, Sb, and W. Stream sediments collected from drainages underlain by slate, but distal to the exposed tin occurrences, are characterized by background levels of As ( 10-60 ppm), Li (16-80 ppm), Sn (5-14 ppm), and W (5-10 ppm). These background levels for As and Sn are much higher than concentrations in typical slates and suggest a broad, weak hydrothermal alteration during mineral-deposit formation in much of the study area. A consistent pattern of Ca>>Mg>Na>K and generally alkaline pH (7 .2-8.2) characterize waters throughout the study area. Dissolved sulfate concentrations range from 10 to 40 ppm for waters draining slates and from 3 to 20 ppm for water draining carbonates. The waters collected in areas of known tin occurrences in the Potato Mountain area are characterized by increased dissolved sulfate (43-75 ppm) and are generally acidic (pH 4.7-6.5), but most trace metals are at or below detection limits. Dissolved arsenic concentrations in the areas of known tin occurrences are at or below 2 ppb. Our data suggest that detrital arsenic and tin from mineral occurrences may be naturally entering the nearshore marine environment.

Inhalation of progesterone inhibits chronic airway inflammation of mice exposed to ozone.

PubMed

Fei, Xia; Bao, Wuping; Zhang, Pengyu; Zhang, Xue; Zhang, Guoqing; Zhang, Yingying; Zhou, Xin; Zhang, Min

2017-05-01

Chronic ozone exposure leads to a model of mice with lung inflammation, emphysema and oxidative stress. Progesterone plays an important role in attenuating the neuroinflammation. We assume that progesterone will reduce the chronic airway inflammation exposed to ozone and evaluate whether combination of progesterone with glucocorticoids results in synergistic effects. C57/BL6 mice were exposed to ozone (2.5ppm, 3h) 12 times over 6 weeks, and were administered with progesterone (0.03 or 0.3mg/L; inhaled) alone or combined with budesonide (BUD) (0.2g/L) after each exposure until the tenth week. Mice were studied 24h after final exposure, cells and inflammatory mediators were assessed in bronchoalveolar lavage fluid (BALF) and lungs used for evaluation of glucocorticoids receptors (GR), p38 mitogen-activated protein kinase (MAPK) phosphorylation and nuclear transcription factor κB (NF-κB) activation. Exposure to ozone resulted in a marked lung neutrophilia. Moreover, in ozone-exposed group, the levels of oxidative stress-related interleukin (IL)-1β, IL-6, IL-8, IL-17A, activated NF-κB and p38MAPK, airway inflammatory cells infiltration density, mean linear intercept (Lm) were greatly increased, FEV 25 and glucocorticoids receptors (GR) were markedly decreased. Comparable to BUD, progesterone treatment dose-dependently led to a significant reduction of IL-1β, IL-6, IL-8, IL-17A, activated NF-κB and p38MAPK, and an increase of FEV 25 and GR. Progesterone combined with BUD resulted in dramatic changes, compared to monotherapy of BUD or progesterone. Therefore, these results demonstrate that chronic ozone exposure has profound airway inflammatory effects counteracted by progesterone and progesterone acts synergistically with glucocorticoids in attenuating the airway inflammation dose-dependently. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ozone-Induced Vascular Contractility and Pulmonary Injury Are Differentially Impacted by Diets Enriched With Coconut Oil, Fish Oil, and Olive Oil.

PubMed

Snow, Samantha J; Cheng, Wan-Yun; Henriquez, Andres; Hodge, Myles; Bass, Virgina; Nelson, Gail M; Carswell, Gleta; Richards, Judy E; Schladweiler, Mette C; Ledbetter, Allen D; Chorley, Brian; Gowdy, Kymberly M; Tong, Haiyan; Kodavanti, Urmila P

2018-05-01

Fish, olive, and coconut oil dietary supplementation have several cardioprotective benefits, but it is not established if they protect against air pollution-induced adverse effects. We hypothesized that these dietary supplements would attenuate ozone-induced systemic and pulmonary effects. Male Wistar Kyoto rats were fed either a normal diet, or a diet supplemented with fish, olive, or coconut oil for 8 weeks. Animals were then exposed to air or ozone (0.8 ppm), 4 h/day for 2 days. Ozone exposure increased phenylephrine-induced aortic vasocontraction, which was completely abolished in rats fed the fish oil diet. Despite this cardioprotective effect, the fish oil diet increased baseline levels of bronchoalveolar lavage fluid (BALF) markers of lung injury and inflammation. Ozone-induced pulmonary injury/inflammation were comparable in rats on normal, coconut oil, and olive oil diets with altered expression of markers in animals fed the fish oil diet. Fish oil, regardless of exposure, led to enlarged, foamy macrophages in the BALF that coincided with decreased pulmonary mRNA expression of cholesterol transporters, cholesterol receptors, and nuclear receptors. Serum microRNA profile was assessed and demonstrated marked depletion of a variety of microRNAs in animals fed the fish oil diet, several of which were of splenic origin. No ozone-specific changes were noted. Collectively, these data indicate that although fish oil offered vascular protection from ozone exposure, it increased pulmonary injury/inflammation and impaired lipid transport mechanisms resulting in foamy macrophage accumulation, demonstrating the need to be cognizant of potential off-target pulmonary effects that might offset the overall benefit of this vasoprotective supplement.

On the interactions among tropospheric ozone levels and typical environmental stresses challenging Mediterranean crops.

PubMed

Fagnano, Massimo; Maggio, Albino

2018-03-01

The main environmental stresses of Italian croplands are discussed in relation to their interactions with ozone effects on crops. Water deficit and salinization are frequent in Mediterranean environments during spring-summer causing a decrease of soil water potential and water uptake by roots and consequently stomatal closure. These stresses also stimulate secondary metabolism and antioxidant accumulation, which also serves as a stress protection mechanism. High concentrations of tropospheric ozone are common all over Italy during the spring-summer season. Ozone injuries to vegetation are related to its penetration into plant tissues, mostly via stomatal uptake, rather than to tropospheric concentrations per se. In several crops, closure of stomata due to drought/salinization reduces ozone entering into leaf tissues and counteracts possible ozone damages. Furthermore, the stimulation of antioxidant synthesis as a response to environmental stresses can represent a further protection factor from ozone injuries for Mediterranean crops.The co-existence of stress-induced stomatal closure and high ozone levels during spring-summer in Mediterranean environments implies that models that do not take into account physiological responses of crops to drought and salinity stress may overestimate ozone damages when stress responses overlap with seasonal ozone peaks. The shift from concentration-based to flux-based approaches has improved the accuracy of models to assess ozone effects on agricultural crops. It is, however, necessary to further refine the flux concept with respect to the plant abiotic stress defense capacity that can differ among genotypes, climatic conditions, and physiological states.

Classical and alternative macrophage activation in the lung following ozone-induced oxidative stress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sunil, Vasanthi R., E-mail: sunilva@pharmacy.rutgers.edu; Patel-Vayas, Kinal; Shen, Jianliang

Ozone is a pulmonary irritant known to cause oxidative stress, inflammation and tissue injury. Evidence suggests that macrophages play a role in the pathogenic response; however, their contribution depends on the mediators they encounter in the lung which dictate their function. In these studies we analyzed the effects of ozone-induced oxidative stress on the phenotype of alveolar macrophages (AM). Exposure of rats to ozone (2 ppm, 3 h) resulted in increased expression of 8-hydroxy-2′-deoxyguanosine (8-OHdG), as well as heme oxygenase-1 (HO-1) in AM. Whereas 8-OHdG was maximum at 24 h, expression of HO-1 was biphasic increasing after 3 h andmore » 48–72 h. Cleaved caspase-9 and beclin-1, markers of apoptosis and autophagy, were also induced in AM 24 h post-ozone. This was associated with increased bronchoalveolar lavage protein and cells, as well as matrix metalloproteinase (MMP)-2 and MMP-9, demonstrating alveolar epithelial injury. Ozone intoxication resulted in biphasic activation of the transcription factor, NFκB. This correlated with expression of monocyte chemotactic protein‐1, inducible nitric oxide synthase and cyclooxygenase‐2, markers of proinflammatory macrophages. Increases in arginase-1, Ym1 and galectin-3 positive anti-inflammatory/wound repair macrophages were also observed in the lung after ozone inhalation, beginning at 24 h (arginase-1, Ym1), and persisting for 72 h (galectin-3). This was associated with increased expression of pro-surfactant protein-C, a marker of Type II cell proliferation and activation, important steps in wound repair. These data suggest that both proinflammatory/cytotoxic and anti-inflammatory/wound repair macrophages are activated early in the response to ozone-induced oxidative stress and tissue injury. -- Highlights: ► Lung macrophages are highly sensitive to ozone induced oxidative stress. ► Ozone induces autophagy and apoptosis in lung macrophages. ► Proinflammatory and wound repair macrophages are activated early after ozone. ► Oxidative stress may contribute to regulating macrophage phenotype and function.« less

Simultaneous lidar observations of the water vapor and ozone signatures of a stratospheric intrusion during the MOHAVE-2009 campaign

NASA Astrophysics Data System (ADS)

Leblanc, T.; McDermid, I. S.; Pérot, K.

2010-12-01

Ozone and water vapor signatures of a stratospheric intrusion were simultaneously observed by the Jet Propulsion Laboratory lidars located at Table Mountain Facility, California (TMF, 34.4N, 117.7W) during the Measurements of Humidity in the Atmosphere and Validation Experiments (MOHAVE-2009) campaign in October 2009. These observations are placed in the context of the meridional displacement and folding of the tropopause, and resulting contrast in the properties of the air masses sampled by lidar. The lidar observations are supported by model data, specifically potential vorticity fields advected by the high-resolution transport model MIMOSA, and by 10-day backward isentropic trajectories. The ozone and water vapor anomalies measured by lidar were largely anti-correlated, and consistent with the assumption of a wet and ozone-poor subtropical upper troposphere, and a dry and ozone-rich extra-tropical lowermost stratosphere. However, it is shown that this anti-correlation relation collapsed just after the stratospheric intrusion event of October 20, suggesting mixed air embedded along the subtropical jet stream and sampled by lidar during its displacement south of TMF (tropopause fold). The ozone-PV expected positive correlation relation held strongly throughout the measurement period, including when a lower polar stratospheric filament passed over TMF just after the stratospheric intrusion. The numerous highly-correlated signatures observed during this event demonstrate the strong capability of the water vapor and ozone lidars at TMF, and provide new confidence in the future detection by lidar of long-term variability of water vapor and ozone in the Upper Troposphere-Lower Stratosphere (UTLS).

Effects of ozonated sewage effluent on reproduction and behavioral endpoints in zebrafish (Danio rerio).

PubMed

Pohl, Johannes; Björlenius, Berndt; Brodin, Tomas; Carlsson, Gunnar; Fick, Jerker; Larsson, D G Joakim; Norrgren, Leif; Örn, Stefan

2018-04-25

Pharmaceutical residues and other micro-contaminants may enter aquatic environments through effluent from sewage treatment plants (STPs) and could cause adverse effects in wild fish. One strategy to alleviate this situation is to improve wastewater treatment by ozonation. To test the effectiveness of full-scale wastewater effluent ozonation at a Swedish municipal STP, the added removal efficiency was measured for 105 pharmaceuticals. In addition, gene expression, reproductive and behavioral endpoints were analyzed in zebrafish (Danio rerio) exposed on-site over 21 days to ozonated or non-ozonated effluents as well as to tap water. Ozone treatment (7 g O 3 /m 3 ) removed pharmaceuticals by an average efficiency of 77% in addition to the conventional treatment, leaving 11 screened pharmaceuticals above detection limits. Differences in biological responses of the exposure treatments were recorded in gene expression, reproduction and behavior. Hepatic vitellogenin gene expression was higher in male zebrafish exposed to the ozonated effluent compared to the non-ozonated effluent and tap water treatments. The reproductive success was higher in fish exposed to ozonated effluent compared to non-ozonated effluent and to tap water. The behavioral measurements showed that fish exposed to the ozonated STP effluent were less active in swimming the first minute after placed in a novel vessel. Ozonation is a capable method for removing pharmaceuticals in effluents. However, its implementation should be thoroughly evaluated for any potential biological impact. Future research is needed for uncovering the factors which produced the in vivo responses in fish. Copyright © 2018 Elsevier B.V. All rights reserved.

Influence of ozone and paracetic acid disinfection on adhesion of resilient liners to acrylic resin.

PubMed

Ekren, Orhun; Ozkomur, Ahmet

2016-08-01

The aim of this study was to evaluate the effect of paracetic acid (PAA) and ozone disinfection on the tensile bond strength (TBS) of silicone-based resilient liners to acrylic resins. One hundred and twenty dumbbell shaped heat-polymerized acrylic resins were prepared. From the mid segment of the specimens, 3 mm of acrylic were grinded off and separated parts were reattached by resilient liners. The specimens were divided into 2 control (control1, control7) and 4 test groups of PAA and ozone disinfection (PAA1, PAA7, ozone1 and ozone7; n=10). While control groups were immersed in distilled water for 10 min (control1) and 7 days (control7), test groups were subjected to PAA (16 g/L) or ozone rich water (4 mg/L) for 1 cycle (10 min for PAA and 60 min for ozone) per day for 7 days prior to tensile tests. Measurements of the TBS were analyzed using 3-way ANOVA and Tukey's HSD test. Adhesive strength of Mollosil decreased significantly by application of ozone disinfection. PAA disinfection had no negative effect on the TBS values of Mollosil and Molloplast B to acrylic resin. Single application of ozone disinfection did not have any negative effect on TBS values of Molloplast B, but prolonged exposure to ozone decreased its adhesive strength. The adhesion of resilient liners to acrylic was not adversely affected by PAA disinfection. Immersion in ozonated water significantly decreased TBS of Mollosil. Prolonged exposure to ozone negatively affects adhesion of Molloplast B to denture base materials.

A reanalysis of ozone on Mars from assimilation of SPICAM observations

NASA Astrophysics Data System (ADS)

Holmes, James A.; Lewis, Stephen R.; Patel, Manish R.; Lefèvre, Franck

2018-03-01

We have assimilated for the first time SPICAM retrievals of total ozone into a Martian global circulation model to provide a global reanalysis of the ozone cycle. Disagreement in total ozone between model prediction and assimilation is observed between 45°S-10°S from LS = 135-180° and at northern polar (60°N-90°N) latitudes during northern fall (LS = 150-195°). Large percentage differences in total ozone at northern fall polar latitudes identified through the assimilation process are linked with excessive northward transport of water vapour west of Tharsis and over Arabia Terra. Modelling biases in water vapour can also explain the underestimation of total ozone between 45°S-10°S from LS = 135-180°. Heterogeneous uptake of odd hydrogen radicals are unable to explain the outstanding underestimation of northern polar total ozone in late northern fall. Assimilation of total ozone retrievals results in alterations of the modelled spatial distribution of ozone in the southern polar winter high altitude ozone layer. This illustrates the potential use of assimilation methods in constraining total ozone where SPICAM cannot observe, in a region where total ozone is especially important for potential investigations of the polar dynamics.

Gases in Sea Ice 1975 - 1979.

DTIC Science & Technology

1979-09-01

surface Beaufort Sea waters were generally 340- 350 ppm and higher (Kelley, 1968; Gosink and Kelley, 1978). 1 Coastal and near-coastal waters...339-341 ppm. Samples of the subnivean air at ARLIS VII generally ran around 350 ppm. The range I was 337-374 ppm, with the samples taken over multi...101 2g CO2 over the winter. The tundra is known to outgas carbon dioxide during freezing and thaw at the rate of 500-90,000 1/hectare (Coyne and Kelley

Measurement of the initial phase of ozone decomposition in water and wastewater by means of a continuous quench-flow system: application to disinfection and pharmaceutical oxidation.

PubMed

Buffle, Marc-Olivier; Schumacher, Jochen; Salhi, Elisabeth; Jekel, Martin; von Gunten, Urs

2006-05-01

Due to a lack of adequate experimental techniques, the kinetics of the first 20s of ozone decomposition in natural water and wastewater is still poorly understood. Introducing a continuous quench-flow system (CQFS), measurements starting 350 ms after ozone addition are presented for the first time. Very high HO. to O3 exposures ratios (Rct=integralHO.dt/integralO3dt) reveal that the first 20s of ozonation present oxidation conditions that are similar to ozone-based advanced oxidation processes (AOP). The oxidation of carbamazepine could be accurately modeled using O3 and HO. exposures measured with CQFS during wastewater ozonation. These results demonstrate the applicability of bench scale determined second-order rate constants for wastewater ozonation. Important degrees of pharmaceutical oxidation and microbial inactivation are predicted, indicating that a significant oxidation potential is available during wastewater ozonation, even when ozone is entirely decomposed in the first 20s.

Removal of micropollutants from Sakarya River water by ozone and membrane processes.

PubMed

Yaman, Fatma Büşra; Çakmakcı, Mehmet; Yüksel, Ebubekir; Özen, İsmail; Gengeç, Erhan

2017-09-01

The removal of some pollutants in the Sakarya River was investigated in this study. Sakarya River located in Turkey flows from the northeast of Afyonkarahisar City to the Black Sea. Nineteen different micropollutants including trihalomethanes (THMs), haloacetic acids (HAAs), endocrine disrupting compound (EDC) and pharmaceuticals personal care product (PPCP) groups, and water quality parameters such as dissolved organic carbon (DOC), ultraviolet absorbance at 254 nm wavelength (UV 254 ), hardness, and conductivity values were examined. To remove the micropollutants and improve the water quality, the treatment was performed with ozone, microfiltration (MF), and ultra-filtration (UF) membranes. The highest treatment efficiency was obtained with 1 mg/L ozone dosage and UP005 UF membrane. The trihalomethan formation potential (THMFP) and haloacetic acid formation potential (HAAFP) decreased with ozone + membrane at a concentration of 79 and 75%, respectively. After the treatment with ozone + membrane, the concentration of the micropollutants in the EDC and PPCP group remained below the detection limit. It was found that by using only membrane and only ozone, the maximum DOC removal efficiency achieved was 46 and 18%, respectively; and with ozone + membrane, this efficiency increased up to 82%. The results from the High-Pressure Size Exclusion Chromatography (HPSEC) analyses pointed that the substances with high molecular weight were converted into substances with low molecular weight after the treatment. The Fourier Transform Infrared (FTIR) analysis results showed that the aromatic and aliphatic functional groups in water changed after the treatment with ozone and that the peak values decreased more after the ozone + membrane treatment.

Sex differences in the expression of lung inflammatory mediators in response to ozone

PubMed Central

Cabello, Noe; Mishra, Vikas; Sinha, Utkarshna; DiAngelo, Susan L.; Chroneos, Zissis C.; Ekpa, Ndifreke A.; Cooper, Timothy K.; Caruso, Carla R.

2015-01-01

Sex differences in the incidence of respiratory diseases have been reported. Women are more susceptible to inflammatory lung disease induced by air pollution and show worse adverse pulmonary health outcomes than men. However, the mechanisms underlying these differences remain unknown. In the present study, we hypothesized that sex differences in the expression of lung inflammatory mediators affect sex-specific immune responses to environmental toxicants. We focused on the effects of ground-level ozone, a major air pollutant, in the expression and regulation of lung immunity genes. We exposed adult male and female mice to 2 ppm of ozone or filtered air (control) for 3 h. We compared mRNA levels of 84 inflammatory genes in lungs harvested 4 h postexposure using a PCR array. We also evaluated changes in lung histology and bronchoalveolar lavage fluid cell counts and protein content at 24 and 72 h postexposure. Our results revealed sex differences in lung inflammation triggered by ozone exposure and in the expression of genes involved in acute phase and inflammatory responses. Major sex differences were found in the expression of neutrophil-attracting chemokines (Ccl20, Cxcl5, and Cxcl2), the proinflammatory cytokine interleukin-6, and oxidative stress-related enzymes (Ptgs2, Nos2). In addition, the phosphorylation of STAT3, known to mediate IL-6-related immune responses, was significantly higher in ozone-exposed mice. Together, our observations suggest that a differential regulation of the lung immune response could be implicated in the observed increased susceptibility to adverse health effects from ozone observed in women vs. men. PMID:26342085

Sex-specific microRNA expression networks in an acute mouse model of ozone-induced lung inflammation.

PubMed

Fuentes, Nathalie; Roy, Arpan; Mishra, Vikas; Cabello, Noe; Silveyra, Patricia

2018-05-08

Sex differences in the incidence and prognosis of respiratory diseases have been reported. Studies have shown that women are at increased risk of adverse health outcomes from air pollution than men, but sex-specific immune gene expression patterns and regulatory networks have not been well studied in the lung. MicroRNAs (miRNAs) are environmentally sensitive posttranscriptional regulators of gene expression that may mediate the damaging effects of inhaled pollutants in the lung, by altering the expression of innate immunity molecules. Male and female mice of the C57BL/6 background were exposed to 2 ppm of ozone or filtered air (control) for 3 h. Female mice were also exposed at different stages of the estrous cycle. Following exposure, lungs were harvested and total RNA was extracted. We used PCR arrays to study sex differences in the expression of 84 miRNAs predicted to target inflammatory and immune genes. We identified differentially expressed miRNA signatures in the lungs of male vs. female exposed to ozone. In silico pathway analyses identified sex-specific biological networks affected by exposure to ozone that ranged from direct predicted gene targeting to complex interactions with multiple intermediates. We also identified differences in miRNA expression and predicted regulatory networks in females exposed to ozone at different estrous cycle stages. Our results indicate that both sex and hormonal status can influence lung miRNA expression in response to ozone exposure, indicating that sex-specific miRNA regulation of inflammatory gene expression could mediate differential pollution-induced health outcomes in men and women.

Physicochemical patterns of ozone absorption by wood

NASA Astrophysics Data System (ADS)

Mamleeva, N. A.; Lunin, V. V.

2016-11-01

Results from studying aspen and pine wood ozonation are presented. The effect the concentration of ozone, the reagent residence time, and the content of water in a sample of wood has on ozone consumption rate and ozone demand are analyzed. The residence time is shown to determine the degree of ozone conversion degree and the depth of substrate destruction. The main patterns of ozone absorption by wood with different moisture content are found. Ways of optimizing the ozonation of plant biomass are outlined.

Concentrations of CH4, CO, CO2, H2, H2O and N2O in the upper stratosphere

NASA Technical Reports Server (NTRS)

Ehhalt, D. H.; Heidt, L. E.; Lueb, R. H.; Martell, E. A.

1975-01-01

On 23 May 1973 a cryogenic air sampler was flown on an Aerobee rocket from White Sands Missile Range. A large air sample was collected between 40 and 50 km altitude and successfully recovered for water vapor and trace gas analysis. The results were as follows: water vapor, 4.0 (+1.3 or - 0.9) ppmV; methane, 0.37 + or - 0.01 ppmV; molecular hydrogen, 0.47 + or - 0.02 ppmV; carbon monoxide, 0.05 + or - 0.01 ppmV; carbon dioxide, 316.2 + or - 2.8 ppmV; and nitrous oxide, 3 + or - 7 ppb.

Survival of the salmonid viruses infectious hematopoietic necrosis (IHNV) and infectious pancreatic necrosis (IPNV) in ozonated, chlorinated, and Untreated waters

USGS Publications Warehouse

Wedemeyer, Gary A.; Nelson, Nancy C.; Smith, Cathy A.

1978-01-01

Ozone and chlorine inactivation curves were determined in three water types at 10 °C for the fish pathogenic viruses infectious hematopoietic necrosis (IHNV) and infectious pancreatic necrosis (IPNV). In phosphate-buffered, distilled water (PBDW) an ozone dose of 0.01 mg/L for 30 or 60 s inactivated IHNV or IPNV, respectively, suspended at a tissue culture 50% infective dose (TCID50) of 104–105/mL. In hard (120 mg/L as CaCO3) and soft water (30 mg/L) lake waters, an ozone application rate of 70 mg∙h−1∙L−1 for 10 min destroyed IHNV. IPNV inactivation in hard water required 90 mg∙O3∙h−1∙L−1 for 10 min but only a 30-s contact time in soft water. The IPNV was also somewhat more resistant to chlorine. In PBDW, a residual of 0.1 mg/L with contact times of 30 and 60 s, respectively, destroyed IHNV and IPNV. In soft lake water IHNV was destroyed within 5 min at 0.5 mg/L, while in hard water a 10-min contact time was required. For IPNV disinfection in soft water, 0.2 mg/L for 10 min was sufficient but this chlorine residual had essentially no effect on IPNV in hard water. Increasing this dose to 0.7 mg/L destroyed IPNV in hard water within 2 min. In untreated waters, IPNV was stable for at least 8 wk in either distilled, soft, or hard lake waters. However, IHNV survived only about 2 wk in distilled and 7 wk in the soft or hard lake waters. We suggest the serious consideration of ozone as a fish disease control agent. Key words: ozone, chlorine disinfection, fish pathogens, viruses

Treatment of toluene and its by-products using an electron beam/ultra-fine bubble hybrid system

NASA Astrophysics Data System (ADS)

Son, Youn-Suk; Kim, Tae-Hun; Choi, Chang Yong; Park, Jun-Hyeong; Ahn, Ji-Won; Dinh, Trieu-Vuong

2018-03-01

Although, until quite recently, many technologies (electron beam (EB), plasma, and ultraviolet) have been studied to overcome disadvantages of conventional methods (such as absorption, adsorption, biofiltration and incineration) for treatment of volatile organic compounds (VOCs), their techniques still have some problems such as formation of a by-product. Generally, it is reported that various by-products are generated from the EB irradiation process to remove VOCs. Therefore, we developed an electron beam/ultra-fine bubble (EB/UB) hybrid system to enhance removal efficiency of a VOC (toluene) and to reduce its by-products formed by electron beam irradiation. As a result, the removal efficiency of toluene (30 ppm) by only EB (10 kGy) was 80.1%. However, the removal efficiency of toluene using the hybrid system (water temperature: 5 ℃) was increased up to 17% when compared to only EB (10 kGy). Additionally, the 65.2% of ozone formed from the EB process was removed in UB reactor. In case of other trace by-products such as undesired VOCs and aldehydes, the levels were lowered down to the below detection limit by the subsequent UB reactor. We also found that the amount of toluene collected and solubilized into water is affected by the water temperature in the UB reactor.

Stratospheric Ozone Loss Over the US in Summer: Recent Advances in Observations of Temperatures, Convective Injection of Condensed Phase Water, and Analyses of Volcanic Injections That are Used to Inform Model Calculations of Catalytic Mechanisms that Control the Response of O3.

NASA Astrophysics Data System (ADS)

Anderson, J. G.

2016-12-01

In the context of changes to the structure of the Earth's climate, consequences to stratospheric ozone over the US in summer are considered. Key advances in observations directly related to the catalytic loss of ozone in the lower stratosphere include: Analysis of high resolution temperature observations over the central US in July and August from both SEAC4RS in situ observations and radio occultation (RO) observations, Inclusion of gravity wave observations from both SEAC4RS and RO measurements, Climatology of NEXRAD weather radar mapping of the 3D convective injection of condensed phase water over the central US in summer, Analysis of the impact on ozone in the lower stratosphere over the US in summer using the AER 2D model calculations of the key rate limiting radicals and rate limiting catalytic loss rates as a function of water vapor, temperature and sulfate loading in the lower stratosphere, Analysis of the impact on ozone in summer over the US under conditions of volcanic injection, overt sulfate addition for solar radiation management, and/or convective injection of water vapor, Emphasis in the analysis is placed specifically on the geographic region over the Great Plains of the US in summer because of the confluence of temperatures and water vapor concentrations that initiate the heterogeneous catalytic conversion of inorganic chlorine, primarily HCl and ClONO2, to free radical form, ClO. The ClO radical in turn engages gas phase catalytic cycles that remove ozone via the photochemical reaction mechanisms virtually identical to the catalytic photochemical processes that remove ozone over the Arctic each year in late spring. In situ observations, in the lower stratosphere of the Arctic, of the principal reaction networks that establish the relationship between observed ozone loss and the threshold in temperature, water vapor and sulfate loading is used to establish the photochemical coordinate system required to analyze ozone loss in the lower stratosphere globally. Analysis is also presented of observed ozone loss resulting from the eruption of Mt. Pinatubo that tests the photochemical structure of large ozone loss at mid-latitude for the range in sulfate loading that accompanies a volcanic eruption.

Dietary antioxidants and the biochemical response to oxidant inhalation. II. Influence of dietary selenium on the biochemical effects of ozone exposure in mouse lung

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elsayed, N.M.; Hacker, A.D.; Kuehn, K.

The influence of dietary selenium (Se) on the pulmonary biochemical response to ozone (O/sub 3/) exposure was examined. For 11 weeks, weanling female strain A/St mice were fed a test diet containing Se either at 0 ppm (-Se) or 1 ppm (+Se). Each diet contained 55 ppm vitamin E (vit E). Mice from each dietary group were exposed to 0.8 +/- 0.05 ppm (1568 +/- 98 micrograms/m3) O/sub 3/ continuously for 5 days. After O/sub 3/ exposure, they were killed along with a matched number of unexposed controls, and their lungs were analyzed for various biochemical parameters. The Se contentsmore » of lung tissue and whole blood were determined, and the levels were seven- to eightfold higher in +Se mice than in -Se mice, reflecting the Se intake of the animals. In unexposed control mice, Se deficiency caused a decline in glutathione peroxidase (GP) activity relative to +Se group. After O/sub 3/ exposure, the GP activity in the -Se group was associated with a lack of stimulation of glutathione reductase (GR) activity and the pentose phosphate cycle (PPC) as assessed by measuring glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) activities. In contrast, the +Se group after O/sub 3/ exposure exhibited increases in all four enzyme activities. Other parameters, e.g., lung weight, total lung protein, DNA and nonprotein sulfhydryl contents, and O/sub 2/ consumption, were not affected by dietary Se in the presence or absence of O/sub 3/ exposure. The data indicate that dietary Se alters the GP activity, which in turn influences the GR and PPC activities in the lung evidently through a reduced demand for NADPH. The level of vit E in the lung was found to be twofold higher in the -Se group than in the +Se group, suggesting a compensatory relationship between Se and vit E in the lung. With O3 exposure, both Se and vit E contents further increased in the lungs of each dietary group.« less

N-nitrosodimethylamine (NDMA) formation during ozonation of wastewater and water treatment polymers.

PubMed

Sgroi, Massimiliano; Roccaro, Paolo; Oelker, Gregg; Snyder, Shane A

2016-02-01

N-Nitrosodimethylamine (NDMA) formation by ozonation was investigated in the effluents of four different wastewater treatment plants destined for alternative reuse. Very high levels of NDMA formation were observed in wastewaters from treatment plants non operating with biological nitrogen removal. Selected experiments showed that hydroxyl radical did not have a significant role in NDMA formation during ozonation of wastewater. Furthermore, ozonation of three different polymers used for water treatment, including polyDADMAC, anionic polyacrylamide, and cationic polyacrylamide, spiked in wastewater did not increase the NDMA formation. Effluent organic matter (EfOM) likely reduced the availability of ozone in water able to react with polymers and quenched the produced ·OH radicals which limited polymer degradation and subsequent NDMA production. Excellent correlations were observed between NDMA formation, UV absorbance at 254 nm, and total fluorescence reduction. These data provide evidence that UV and fluorescence surrogates could be used for monitoring and/or controlling NDMA formation during ozonation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ozone as a laundry agent on orbit and on the ground

NASA Technical Reports Server (NTRS)

Agosto, William N.

1994-01-01

Ozone (03), is the strongest commercial oxidizing agent for aqueous systems and may be ideal for space station laundering operations. It can be generated electronically from air in situ. It kills virtually all microorganisms, attacks many organics and inorganics, and breaks down stable ring structures of benzene and related oils when coupled with ultra violet radiation. It cleans and disinfects in cold water without the need for detergent. It leaves no residues. Ozone permits up to 90% wash water recycling and it eliminates wash time, water volume, and recycling problems of a detergent rinse. Ozone is self purging and converts spontaneously to oxygen. It can be rapidly purged by well established catalytic and thermal processes. Scaling of an ozone laundering system for space station may have commercial applications in a consumer model for home use.

Exploration on the technology for ozone reduction in urban sewage treatment

NASA Astrophysics Data System (ADS)

Yang, Min; Sun, Yi; Han, Zhicheng; Liu, Jun

2017-05-01

With the rapid development of China’s economy, urban water consumption is increasing. However, sewage treatment plants will produce large amounts of sludge after treatment of sewage. Generally, and the sludge treatment costs are relatively high. Therefore, the problem about how to deal with the sewage sludge becomes the hot issues. Municipal waste water treatment plant produces a lot of sludge. This paper summarized the abroad study of ozonation minimization technology. Introduction and discussion were made on the principle of ozonated efficiency of sludge minimization, the efficiency of sludge minimization and the relationship between efficiency and ozone dosage, as well the effect of return sludge ozonated on waste water treatment running and the sludge setting and the dewatering characteristic. The economic estimation was also made on this technology. It’s showed that sludge minimization technology exhibits extensive application foreground.

Water Content of Lunar Alkali Fedlspar

NASA Technical Reports Server (NTRS)

Mills, R. D.; Simon, J. I.; Wang, J.; Alexander, C. M. O'D.; Hauri, E. H.

2016-01-01

Detection of indigenous hydrogen in a diversity of lunar materials, including volcanic glass, melt inclusions, apatite, and plagioclase suggests water may have played a role in the chemical differentiation of the Moon. Spectroscopic data from the Moon indicate a positive correlation between water and Th. Modeling of lunar magma ocean crystallization predicts a similar chemical differentiation with the highest levels of water in the K- and Th-rich melt residuum of the magma ocean (i.e. urKREEP). Until now, the only sample-based estimates of water content of KREEP-rich magmas come from measurements of OH, F, and Cl in lunar apatites, which suggest a water concentration of < 1 ppm in urKREEP. Using these data, predict that the bulk water content of the magma ocean would have <10 ppm. In contrast, estimate water contents of 320 ppm for the bulk Moon and 1.4 wt % for urKREEP from plagioclase in ferroan anorthosites. Results and interpretation: NanoSIMS data from granitic clasts from Apollo sample 15405,78 show that alkali feldspar, a common mineral in K-enriched rocks, can have approx. 20 ppm of water, which implies magmatic water contents of approx. 1 wt % in the high-silica magmas. This estimate is 2 to 3 orders of magnitude higher than that estimated from apatite in similar rocks. However, the Cl and F contents of apatite in chemically similar rocks suggest that these melts also had high Cl/F ratios, which leads to spuriously low water estimates from the apatite. We can only estimate the minimum water content of urKREEP (+ bulk Moon) from our alkali feldspar data because of the unknown amount of degassing that led to the formation of the granites. Assuming a reasonable 10 to 100 times enrichment of water from urKREEP into the granites produces an estimate of 100-1000 ppm of water for the urKREEP reservoir. Using the modeling of and the 100-1000 ppm of water in urKREEP suggests a minimum bulk silicate Moon water content between 2 and 20 ppm. However, hydrogen loss was likely very significant in the evolution of the lunar mantle. Conclusions: Lunar granites crystallized between 4.3-3.8 Ga from relatively wet melts that degassed upon crystallization. The formation of these granites likely removed significant amounts of water from some mantle source regions, e.g. later mare basalts predicting derivation from a mantle with <10 ppm water. However, this would have been a heterogeneous pro-cess based on K distribution. Thus some, if not most of the mantle may not have been devolatilized by this process; as seen by water in volcanic glasses and melt inclusions.

Balloon Borne Soundings of Water Vapor, Ozone and Temperature in the Upper Tropospheric and Lower Stratosphere as Part of the Second SAGE III Ozone Loss and Validation Experiment (SOLVE-2)

NASA Technical Reports Server (NTRS)

Voemel, Holger

2004-01-01

The main goal of our work was to provide in situ water vapor and ozone profiles in the upper troposphere and lower stratosphere as reference measurements for the validation of SAGE III water vapor and ozone retrievals. We used the NOAA/CMDL frost point hygrometer and ECC ozone sondes on small research balloons to provide continuous profiles between the surface and the mid stratosphere. The NOAA/CMDL frost point hygrometer is currently the only lightweight balloon borne instrument capable of measuring water vapor between the lower troposphere and middle stratosphere. The validation measurements were based in the arctic region of Scandinavia for northern hemisphere observations and in New Zealand for southern hemisphere observations and timed to coincide with overpasses of the SAGE III instrument. In addition to SAGE III validation we also tried to coordinate launches with other instruments and studied dehydration and transport processes in the Arctic stratospheric vortex.

Spectroscopic signatures of ozone at the air–water interface and photochemistry implications

PubMed Central

Anglada, Josep M.; Martins-Costa, Marilia; Ruiz-López, Manuel F.; Francisco, Joseph S.

2014-01-01

First-principles simulations suggest that additional OH formation in the troposphere can result from ozone interactions with the surface of cloud droplets. Ozone exhibits an affinity for the air–water interface, which modifies its UV and visible light spectroscopic signatures and photolytic rate constant in the troposphere. Ozone cross sections on the red side of the Hartley band (290- to 350-nm region) and in the Chappuis band (450–700 nm) are increased due to electronic ozone–water interactions. This effect, combined with the potential contribution of the O3 + hν → O(3P) + O2(X3Σg−) photolytic channel at the interface, leads to an enhancement of the OH radical formation rate by four orders of magnitude. This finding suggests that clouds can influence the overall oxidizing capacity of the troposphere on a global scale by stimulating the production of OH radicals through ozone photolysis by UV and visible light at the air–water interface. PMID:25071195

Ozone/graphene oxide catalytic oxidation: a novel method to degrade emerging organic contaminant N, N-diethyl-m-toluamide (DEET).

PubMed

Liu, Jia-Nan; Chen, Zhuo; Wu, Qian-Yuan; Li, Ang; Hu, Hong-Ying; Yang, Cheng

2016-08-11

N, N-diethyl-m-toluamide (DEET) is one of the important emerging contaminants that are being increasingly detected in reclaimed water as well as in drinking water sources. However, DEET is refractory to conventional biological treatment and pure ozone which is absent of hydroxyl radical. Current researches on the efficient removal of DEET are still quite limited. This study utilizes a novel method, namely ozone/graphene oxide (O3/GO), to investigate the effects on DEET removal in aqueous systems, especially in reclaimed water. The results indicate that the DEET degradation rate was significantly accelerated through the combined effect of GO and ozonation which can yield abundant hydroxyl radical, compared to pure ozone condition. According to hydroxyl radical scavenging experiments, hydroxyl radical was found to play a dominant role in synergistic removal of DEET. These findings can offer sound suggestions for future research on the removal of emerging organic contaminants. The information could also be beneficial to reclaimed water safety and sustainable management.

Membrane contactor/separator for an advanced ozone membrane reactor for treatment of recalcitrant organic pollutants in water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chan, Wai Kit, E-mail: kekyeung@ust.hk; Joueet, Justine; Heng, Samuel

An advanced ozone membrane reactor that synergistically combines membrane distributor for ozone gas, membrane contactor for pollutant adsorption and reaction, and membrane separator for clean water production is described. The membrane reactor represents an order of magnitude improvement over traditional semibatch reactor design and is capable of complete conversion of recalcitrant endocrine disrupting compounds (EDCs) in water at less than three minutes residence time. Coating the membrane contactor with alumina and hydrotalcite (Mg/Al=3) adsorbs and traps the organics in the reaction zone resulting in 30% increase of total organic carbon (TOC) removal. Large surface area coating that diffuses surface chargesmore » from adsorbed polar organic molecules is preferred as it reduces membrane polarization that is detrimental to separation. - Graphical abstract: Advanced ozone membrane reactor synergistically combines membrane distributor for ozone, membrane contactor for sorption and reaction and membrane separator for clean water production to achieve an order of magnitude enhancement in treatment performance compared to traditional ozone reactor. Highlights: Black-Right-Pointing-Pointer Novel reactor using membranes for ozone distributor, reaction contactor and water separator. Black-Right-Pointing-Pointer Designed to achieve an order of magnitude enhancement over traditional reactor. Black-Right-Pointing-Pointer Al{sub 2}O{sub 3} and hydrotalcite coatings capture and trap pollutants giving additional 30% TOC removal. Black-Right-Pointing-Pointer High surface area coating prevents polarization and improves membrane separation and life.« less

Ozone pretreatment of process waste water generated in course of fluoroquinolone production.

PubMed

Daoud, Fares; Pelzer, David; Zuehlke, Sebastian; Spiteller, Michael; Kayser, Oliver

2017-10-01

During production of active pharmaceutical ingredients, process waste water is generated at several stages of manufacturing. Whenever possible, the resulting waste water will be processed by conventional waste water treatment plants. Currently, incineration of the process waste water is the method to eliminate compounds with high biological activity. Thus, ozone treatment followed by biological waste water treatment was tested as an alternative method. Two prominent representatives of the large group of fluoroquinolone antibiotics (ciprofloxacin and moxifloxacin) were investigated, focussing on waste water of the bulk production. Elimination of the target compounds and generation of their main transformation products were determined by liquid chromatography - high resolution mass spectrometry (LC-HRMS). The obtained results demonstrated, that the concentration of moxifloxacin and its metabolites can be effectively reduced (>99.7%) prior entering the receiving water. On the contrary, the concentration of ciprofloxacin and its metabolites remained too high for safe discharge, necessitating application of prolonged ozonation for its further degradation. The required ozonation time can be estimated based on the determined kinetics. To assure a low biological activity the ecotoxicity of the ozonated waste water was investigated using three trophic levels. By means of multiple-stage mass spectrometry (MS n ) experiments several new transformation products of the fluoroquinolones were identified. Thus, previously published proposed structures could be corrected or confirmed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Major Upgrades to the AIRS Version-6 Ozone Profile Methodology

NASA Technical Reports Server (NTRS)

Susskind, Joel; Blaisdell, John; Iredell, Lena

2015-01-01

This research is a continuation of part of what was shown at the last AIRS Science Team Meeting in the talk Improved Water Vapor and Ozone Profiles in SRT AIRS Version-6.X and the AIRS February 11, 2015 NetMeeting Further improvements in water vapor and ozone profiles compared to Version-6.AIRS Version-6 was finalized in late 2012 and is now operational. Version-6 contained many significant improvements in retrieval methodology compared to Version-5. However, Version-6 retrieval methodology used for the water vapor profile q(p) and ozone profile O3(p) retrievals is basically unchanged from Version-5, or even from Version-4. Subsequent research has made significant improvements in both water vapor and O3 profiles compared to Version-6. This talk will concentrate on O3 profile retrievals. Improvements in water vapor profile retrievals are given in a separate presentation.

[Ru/AC catalyzed ozonation of recalcitrant organic compounds].

PubMed

Wang, Jian-Bing; Hou, Shao-Pei; Zhou, Yun-Rui; Zhu, Wan-Peng; He, Xu-Wen

2009-09-15

Ozonation and Ru/AC catalyzed ozonation of dimethyl phthalate (DMP), phenols and disinfection by-products precursors were studied. It shows that Ru/AC catalyst can obviously enhance the mineralization of organic compounds. In the degradation of DMP, TOC removal was 28.84% by ozonation alone while it was 66.13% by catalytic ozonation. In the oxidation of 23 kinds of phenols, TOC removals were 9.57%-56.08% by ozonation alone while they were 41.81%-82.32% by catalytic ozonation. Compared to ozonation alone, Ru/AC catalyzed ozonation was more effective for the reduction of disinfection by-products formation potentials in source water. The reduction of haloacetic acids formation potentials was more obvious than thichlomethane formation potentials. After the treatment by catalytic ozonation, the haloacetic acids formation potentials decreased from 144.02 microg/L to 58.50 microg/L, which was below the standard value of EPA. However ozonation alone could not make it reach the standard. The treatments of source water by BAC, O3 + BAC, O3/AC + BAC and Ru/AC + O3 + BAC were also studied. In the four processes, TOC removal was 3.80%, 20.14%, 27.45% and 48.30% respectively, COD removal was 4.37%, 27.22%, 39.91% and 50.00% respectively, UV254 removal was 8.16%, 62.24%, 67.03% and 84.95% respectively. Ru/AC + O3 + BAC process is more effective than the other processes for the removal of TOC, COD and UV254 and no ruthenium leaching observed in the solution. It is a promising process for the treatment of micro polluted source water.

EFFECTS OF OZONE AND WATER STRESS ON CANOPY TEMPERATURE, WATER USE, AND WATER USE EFFICIENCY OF ALFALFA

EPA Science Inventory

Ozone (O3) and soil water deficit are two environmental stresses that significantly affect the growth and yield of alfalfa. However, little is known of the responses of field-grown alfalfa to O3, and the effects of the interaction between O3 and water stress on canopy temperature...

Towards reducing DBP formation potential of drinking water by favouring direct ozone over hydroxyl radical reactions during ozonation.

PubMed

De Vera, Glen Andrew; Stalter, Daniel; Gernjak, Wolfgang; Weinberg, Howard S; Keller, Jurg; Farré, Maria José

2015-12-15

When ozonation is employed in advanced water treatment plants to produce drinking water, dissolved organic matter reacts with ozone (O3) and/or hydroxyl radicals (OH) affecting disinfection byproduct (DBP) formation with subsequently used chlorine-based disinfectants. This study presents the effects of varying exposures of O3 and •OH on DBP concentrations and their associated toxicity generated after subsequent chlorination. DBP formation potential tests and in vitro bioassays were conducted after batch ozonation experiments of coagulated surface water with and without addition of tertiary butanol (t-BuOH, 10 mM) and hydrogen peroxide (H2O2, 1 mg/mg O3), and at different pH (6-8) and transferred ozone doses (0-1 mg/mg TOC). Although ozonation led to a 24-37% decrease in formation of total trihalomethanes, haloacetic acids, haloacetonitriles, and trihaloacetamides, an increase in formation of total trihalonitromethanes, chloral hydrate, and haloketones was observed. This effect however was less pronounced for samples ozonated at conditions favoring molecular ozone (e.g., pH 6 and in the presence of t-BuOH) over •OH reactions (e.g., pH 8 and in the presence of H2O2). Compared to ozonation only, addition of H2O2 consistently enhanced formation of all DBP groups (20-61%) except trihalonitromethanes. This proves that •OH-transformed organic matter is more susceptible to halogen incorporation. Analogously, adsorbable organic halogen (AOX) concentrations increased under conditions that favor •OH reactions. The ratio of unknown to known AOX, however, was greater at conditions that promote direct O3 reactions. Although significant correlation was found between AOX and genotoxicity with the p53 bioassay, toxicity tests using 4 in vitro bioassays showed relatively low absolute differences between various ozonation conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nitrate formation during ozonation as a surrogate parameter for abatement of micropollutants and the N-nitrosodimethylamine (NDMA) formation potential.

PubMed

Song, Yang; Breider, Florian; Ma, Jun; von Gunten, Urs

2017-10-01

In this study, nitrate formation from ammonium and/or dissolved organic nitrogen (DON) was investigated as a novel surrogate parameter to evaluate the abatement of micropollutants during ozonation of synthetic waters containing natural organic matter (NOM) isolates, a natural water and secondary wastewater effluents. Nitrate formation during ozonation was compared to the changes in UV absorbance at 254 nm (UVA 254 ) including the effect of pH. For low specific ozone doses UVA 254 was abated more efficiently than nitrate was formed. This is due to a relatively slow rate-limiting step for nitrate formation from the reaction between ozone and a proposed nitrogen-containing intermediate. This reaction cannot compete with the fast reactions between ozone and UV-absorbing moieties (e.g., activated aromatic compounds). To further test the kinetics of nitrate formation, two possible intermediates formed during ozonation of DON were tested. At pH 7, nitrate was formed during ozonation of acetone oxime and methyl nitroacetate with second-order rate constants of 256.7 ± 4.7 M -1  s -1 and 149.5 ± 5.8 M -1  s -1 , respectively. The abatement of the selected micropollutants (i.e., 17α-ethinylestradiol (EE2), carbamazepine (CBZ), bezafibrate (BZF), ibuprofen (IBU), and p-chlorobenzoic acid (pCBA)) was investigated for specific ozone doses ≤1.53 mgO 3 /mgDOC and its efficiency depended strongly on the reactivity of the selected compounds with ozone. The relative abatement of micropollutants (i.e., EE2 and CBZ) with high ozone reactivity showed linear relationships with nitrate formation. The abatement of micropollutants with intermediate-low ozone reactivity (BZF, IBU, and pCBA) followed one- and two-phase behaviors relative to nitrate formation during ozonation of water samples containing high and low concentrations of nitrate-forming DON, respectively. During ozonation of a wastewater sample, the N-nitrosodimethylamine formation potential (NDMA-FP) during chloramination decreased with increasing specific ozone doses. A good correlation was obtained between NDMA-FP abatement and nitrate formation. Therefore, nitrate formation after pre-ozonation may be a useful parameter to estimate the reduction of the NDMA-FP during post-chloramination. Overall, the results of this study suggest that nitrate formation (possibly in combination with UVA 254 abatement) during ozonation of DON-containing waters may be a good surrogate for assessing the abatement of micropollutants and the NDMA-FP. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dissolved organic nitrogen and its biodegradable portion in a water treatment plant with ozone oxidation.

PubMed

Wadhawan, Tanush; Simsek, Halis; Kasi, Murthy; Knutson, Kristofer; Prüβ, Birgit; McEvoy, John; Khan, Eakalak

2014-05-01

Biodegradability of dissolved organic nitrogen (DON) has been studied in wastewater, freshwater and marine water but not in drinking water. Presence of biodegradable DON (BDON) in water prior to and after chlorination may promote formation of nitrogenous disinfectant by-products and growth of microorganisms in the distribution system. In this study, an existing bioassay to determine BDON in wastewater was adapted and optimized, and its application was tested on samples from four treatment stages of a water treatment plant including ozonation and biologically active filtration. The optimized bioassay was able to detect BDON in 50 μg L(-1) as N of glycine and glutamic solutions. BDON in raw (144-275 μg L(-1) as N), softened (59-226 μg L(-1) as N), ozonated (190-254 μg L(-1) as N), and biologically filtered (17-103 μg L(-1) as N) water samples varied over a sampling period of 2 years. The plant on average removed 30% of DON and 68% of BDON. Ozonation played a major role in increasing the amount of BDON (31%) and biologically active filtration removed 71% of BDON in ozonated water. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of ozonation on the removal of cyanobacterial toxins during drinking water treatment.

PubMed Central

Hoeger, Stefan J; Dietrich, Daniel R; Hitzfeld, Bettina C

2002-01-01

Water treatment plants faced with toxic cyanobacteria have to be able to remove cyanotoxins from raw water. In this study we investigated the efficacy of ozonation coupled with various filtration steps under different cyanobacterial bloom conditions. Cyanobacteria were ozonated in a laboratory-scale batch reactor modeled on a system used by a modern waterworks, with subsequent activated carbon and sand filtration steps. The presence of cyanobacterial toxins (microcystins) was determined using the protein phosphatase inhibition assay. We found that ozone concentrations of at least 1.5 mg/L were required to provide enough oxidation potential to destroy the toxin present in 5 X 10(5 )Microcystis aeruginosa cells/mL [total organic carbon (TOC), 1.56 mg/L]. High raw water TOC was shown to reduce the efficiency of free toxin oxidation and destruction. In addition, ozonation of raw waters containing high cyanobacteria cell densities will result in cell lysis and liberation of intracellular toxins. Thus, we emphasize that only regular and simultaneous monitoring of TOC/dissolved organic carbon and cyanobacterial cell densities, in conjunction with online residual O(3) concentration determination and efficient filtration steps, can ensure the provision of safe drinking water from surface waters contaminated with toxic cyanobacterial blooms. PMID:12417484

Technology for Water Treatment (National Water Management)

NASA Technical Reports Server (NTRS)

1992-01-01

The buildup of scale and corrosion is the most costly maintenance problem in cooling tower operation. Jet Propulsion Laboratory successfully developed a non-chemical system that not only curbed scale and corrosion, but also offered advantages in water conservation, cost savings and the elimination of toxic chemical discharge. In the system, ozone is produced by an on-site generator and introduced to the cooling tower water. Organic impurities are oxidized, and the dissolved ozone removes bacteria and scale. National Water Management, a NASA licensee, has installed its ozone advantage systems at some 200 cooling towers. Customers have saved money and eliminated chemical storage and discharge.

21 CFR 184.1563 - Ozone.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ozone. 184.1563 Section 184.1563 Food and Drugs....1563 Ozone. (a) Ozone (O3, CAS Reg. No. 10028-15-6) is an unstable blue gas with a pungent... maximum residual level at the time of bottling of 0.4 milligram of ozone per liter of bottled water...

OZONE-SCAVENGING REAGENTS SUITABLE FOR USE IN THE QUANTITATIVE DETERMINATION OF ALDEHYDES AS THE O-(2,3,4,5,6-PENTAFLUOROBENZYL)OXIMES BY GC-ECD

EPA Science Inventory

Previously, we reported interference due to several ozone-scavenging reagents (OSRs) in the quantitation of aldehydes using 0-(2,3,4,5,6-pentafluorobenzyl)oxylamine (PFBOA) in the analysis of ozonated waters. Scavenging ozone is essential if ozonation byproduct concentrations ar...

Radical production from the interaction of ozone and PUFA as demonstrated by electron spin resonance spin-trapping techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pryor, W.A.; Prier, D.G.; Church, D.F.

1981-02-01

There is considerable evidence that indicates that a fraction of the damage caused by ozone to cellular systems involves radical-mediated reactions. The most direct method for probing the mechanism by which ozone reacts with target molecules such as polyunsaturated fatty acids involves the use of electron spin resonance. In 1968, Goldstein et al. reported that ESR signals were observed when 40 ppM ozone in air is bubbled through linoleic acid. We have repeated this experiment and have performed several experiments modified from this design; in none of these do we observe ESR signals. We have studied the reaction of ozonemore » with PUFA at -78/sup 0/C using spin traps. Spin traps themselves react with ozone, but the following protocol avoids that reaction. (1) Ozone in air or oxygen-free ozone is allowed to bubble through the sample in Freon-11 in an ESR tube at -78/sup 0/C; no ESR absorption is observed. (2) Unreacted ozone is flushed out with argon or nitrogen. (3) The spin trap in Freon-11 is added to give a 0.1 M solution, still at -78/sup 0/C; no ESR signal is observed. (4) The tube is allowed to warm slowly. At about -45/sup 0/C, the ESR spectra of spin adducts appear. Using this method with methyl linoleate we observe spin adducts of alkoxy radicals and also a signal that is consistent with a carbon radical with one ..cap alpha..-H. We hypothesize that an intermediate is formed from the reaction of ozone with PUFA that is stable at -78/sup 0/Cbut decomposes to form radicals at about -45/sup 0/C. We tentatively identify the intermediate as a trioxide on the basis of analogies and its temperature profile for decomposition to radicals. It appears reasonable to suggest that the reaction(s) responsible for the production of radicals under these low-temperature conditions also occurs at room temperature. Although the low-temperature intermediate cannot be observed at ambient temperatures, radicals from it could be responsible for the effects on autoxidation that are induced by ozone.« less

Laboratory measurements of physical, chemical, and optical characteristics of Lake Chicot sediment waters

NASA Technical Reports Server (NTRS)

Witte, W. G.; Whitlock, C. H.; Usry, J. W.; Morris, W. D.; Gurganus, E. A.

1981-01-01

Reflectance, chromaticity, diffuse attenuation, beam attenuation, and several other physical and chemical properties were measured for various water mixtures of lake bottom sediment. Mixture concentrations range from 5 ppm to 700 ppm by weight of total suspended solids in filtered deionized tap water. Upwelled reflectance is a nonlinear function of remote sensing wave lengths. Near-infrared wavelengths are useful for monitoring highly turbid waters with sediment concentrations above 100 ppm. It is found that both visible and near infrared wavelengths, beam attenuation correlates well with total suspended solids ranging over two orders of magnitude.

Toxicology and carcinogenesis studies of sodium nitrite (CAS NO. 7632-00-0) in F344/N rats and B6C3F1 mice (drinking water studies).

PubMed

2001-05-01

Sodium nitrite is used as a color fixative and preservative in meats and fish. It is also used in manufacturing diazo dyes, nitroso compounds, and other organic compounds; in dyeing and printing textile fabrics and bleaching fibers; in photography; as a laboratory reagent and a corrosion inhibitor; in metal coatings for phosphatizing and detinning; and in the manufacture of rubber chemicals. Sodium nitrite also has been used in human and veterinary medicine as a vasodilator, a bronchial dilator, an intestinal relaxant, and an antidote for cyanide poisoning. Sodium nitrite was nominated by the FDA for toxicity and carcinogenesis studies based on its widespread use in foods. Male and female F344/N rats and B6C3F1 mice were exposed to sodium nitrite (99% pure) in drinking water for 14 weeks or 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium, rat and mouse bone marrow, and mouse peripheral blood. 14-WEEK STUDY IN RATS: Groups of 10 male and 10 female rats were exposed to 0, 375, 750, 1500, 3,000, or 5000 ppm sodium nitrite (equivalent to average daily doses of approximately 30, 55, 115, 200, or 310 mg sodium nitrite/kg body weight to males and 40, 80, 130, 225, or 345 mg/kg to females) in drinking water for 14 weeks. Clinical pathology study groups of 15 male and 15 female rats were exposed to the same concentrations for 70 or 71 days. One female exposed to 3000 ppm died before the end of the study. Body weights of males exposed to 3000 or 5000 ppm and females exposed to 5000 ppm were significantly less than those of the controls. Water consumption by 5000 ppm males and 3000 and 5000 ppm females was less than that by the controls at weeks 2 and 14. Clinical findings related to sodium nitrite exposure included brown discoloration in the eyes and cyanosis of the mouth, tongue, ears, and feet of males exposed to 3000 or 5000 ppm and of females exposed to 1500 ppm or greater. Reticulocyte counts were increased in males and females exposed to 3000 or 5000 ppm. The erythron was decreased on day 19 but increased by week 14 in males and females exposed to 5000 ppm. Methemoglobin concentrations were elevated in almost all exposed groups throughout the 14 week study; a no-observed-adverse-effect level was not achieved. The relative kidney and spleen weights of males and females exposed to 3000 or 5000 ppm were significantly greater than those of the controls. Sperm motility in 1500 and 5000 ppm males was significantly decreased. Increased erythropoietic activity in the bone marrow of exposed males and females was observed. The incidences of squamous cell hyperplasia of the forestomach in 5000 ppm males and females were significantly increased. 14-WEEK STUDY IN MICE: Groups of 10 male and 10 female B6C3F1 mice were exposed to 0, 375, 750, 1500, 3000, or 5000 ppm sodium nitrite (equivalent to average daily doses of approximately 90, 190, 345, 750, or 990 mg/kg to males and 120, 240, 445, 840, or 1230 mg/kg to females) in drinking water for 14 weeks. Body weights of males exposed to 5000 ppm were significantly less than those of the controls. Water consumption by males exposed to 1500 ppm or greater was slightly less than that by the controls at week 13. Relative spleen weights of 3000 and 5000 ppm males and absolute and relative heart, kidney, liver, and spleen weights of females exposed to 3000 or 5000 ppm were greater than those of the control groups. Sperm motility was decreased in 5000 ppm males, and the estrous cycles of 1500 and 5000 ppm females were significantly longer than in the controls. There were increased incidences of squamous cell hyperplasia of the forestomach in 5000 ppm males and females, extramedullary hematopoiesis of the spleen in 3000 and 5000 ppm males and 1500 ppm or greater females, and degeneration of the testis in 3000 and 5000 ppm males. 2-YEAR STUDY IN RATS: Groups of 50 male and 50 female rats were exposed to 0, 750, 1500, or 3000 ppm sodium nitrite (equivalent to average daily doses of approximately 35, 70, or 130 mg/kg to males and 40, 8d 40, 80, or 150 mg/kg to females) in drinking water for 2 years. For toxicokinetic studies of plasma nitrite and blood methemoglobin, 10 male and 10 female special study rats were exposed to the same concentrations for 12 months. Survival of exposed groups was similar to that of the controls. Mean body weights of males and females exposed to 3000 ppm were less than those of the controls throughout the study. Water consumption by males and females exposed to 3000 ppm was less than that by the controls throughout the study, and that by the other exposed groups was generally less after week 14. The incidences of hyperplasia of the forestomach epithelium in males and females exposed to 3000 ppm were significantly greater than those in the control groups. The incidence of fibroadenoma of the mam mary gland was significantly increased in females exposed to 1500 ppm, and the incidences of multiple fibroadenoma were increased in 750 ppm and 1500 ppm females; however, these neoplasms occur with a high background incidence, and no increase was seen in the 3000 ppm group. The incidences of mononuclear cell leukemia were significantly decreased in males and females exposed to 1500 or 3000 ppm. 2-YEAR STUDY IN MICE: Groups of 50 male and 50 female B6C3F1 mice were exposed to 0, 750, 1500, or 3000 ppm sodium nitrite (equivalent to average daily doses of approximately 60, 120, or 220 mg/kg to males and 45, 90, or 165 mg/kg to females) in drinking water for 2 years. Survival of exposed groups was similar to that of the controls; mean body weights of 3000 ppm females were less than those of the controls throughout the study. Exposed groups generally consumed less water than the control groups. The incidences of squamous cell papilloma or carcinoma (combined) in the forestomach of female mice occurred with a positive trend. The incidence of hyperplasia of the glandular stomach epithelium was significantly greater in 3000 ppm males than in the controls. Sodium nitrite was mutagenic in Salmonella typhimurium strain TA100, with and without Aroclor 1254-induced hamster and rat liver S9 enzymes; no mutagenicity was observed in strain TA98. Results of acute bone marrow micronucleus tests with sodium nitrite in male rats and mice by intraperitoneal injection were negative. In addition, a peripheral blood micronucleus assay conducted with mice from the 14-week study gave negative results. Under the conditions of this 2-year drinking water study, there was no evidence of carcinogenic activity of sodium nitrite in male or female F344/N rats exposed to 750, 1500, or 3000 ppm. There was no evidence of carcinogenic activity of sodium nitrite in male B6C3F1 mice exposed to 750, 1500, or 3000 ppm. There was equivocal evidence of carcinogenic activity of sodium nitrite in female B6C3F1 mice based on the positive trend in the incidences of squamous cell papilloma or carcinoma (combined) of the forestomach. Exposure to sodium nitrite in drinking water resulted in increased incidences of epithelial hyperplasia in the forestomach of male and female rats and in the glandular stomach of male mice. Decreased incidences of mononuclear cell leukemia occurred in male and female rats.

Ecosystem Consequences of Prolonged Ozone Pollution in the Southern Sierra Nevada

NASA Astrophysics Data System (ADS)

Cousins, S.; Battles, J. J.; Cisneros, R.; Esperanza, A.; Swenson, D.

2015-12-01

While acute O3 exposure is widely known to damage plant tissues, the chronic effects on long lived organisms such as trees remain unclear. In the southern Sierra Nevada, O3 pollution has afflicted pine-dominated forests for over 40 years. Here we report the results of a long-term study of O3 impact on tree injury, growth, and mortality. Our study employed a network of forest plots along a gradient of O3 pollution with recurring measurements from 1991-2012. Over the same period and locations, summer O3 was monitored via partnership with USNPS and USFS, making this one of the longest known ecosystem studies of O3 pollution and its effects. We found that exposure at the most polluted sites declined 33%, from a W126 index of 20.12 ppm-hrs in 1992 to 13.5 ppm-hrs in 2012. The severity of foliar pollution damage at these sites also declined, from 43.9 on the 0-100 Ozone Injury Index (OII) scale to 34.2, a drop of 22%. At locations with lower O3 exposure, damage declined from OII of 16.9 to 9.2. Mean annual tree mortality rates over the 20 year period, calculated with a profile likelihood approach, were 0.5%/yr (95% CI 0.3 to 0.8 %/yr). This rate is similar to that of healthy canopy trees in similar unpolluted stands. However, low and declining tree growth rates reveal possible ecosystem impacts of prolonged exposure to pollution. Across affected sites, mean relative growth rates were 1.1%/yr in 1991-2000, and just 0.9%/yr in 2000-2011, a decline of 15.6% in the second decade. Initial analyses suggest that tree damage is positively correlated with June-October O3, as indicated by previous studies. Further analysis will explore the drivers of ecosystem impacts and roles of other natural and anthropogenic stressors, including variation in climatic water deficit. Understanding the consequences of prolonged O3 exposure on both individual trees and complex forest ecosystems helps identify the hidden environmental costs of tropospheric O3 and potential benefits of cleaner air.

Ozonation of oil sands process-affected water accelerates microbial bioremediation.

PubMed

Martin, Jonathan W; Barri, Thaer; Han, Xiumei; Fedorak, Phillip M; El-Din, Mohamed Gamal; Perez, Leonidas; Scott, Angela C; Jiang, Jason Tiange

2010-11-01

Ozonation can degrade toxic naphthenic acids (NAs) in oil sands process-affected water (OSPW), but even after extensive treatment a residual NA fraction remains. Here we hypothesized that mild ozonation would selectively oxidize the most biopersistent NA fraction, thereby accelerating subsequent NA biodegradation and toxicity removal by indigenous microbes. OSPW was ozonated to achieve approximately 50% and 75% NA degradation, and the major ozonation byproducts included oxidized NAs (i.e., hydroxy- or keto-NAs). However, oxidized NAs are already present in untreated OSPW and were shown to be formed during the microbial biodegradation of NAs. Ozonation alone did not affect OSPW toxicity, based on Microtox; however, there was a significant acceleration of toxicity removal in ozonated OSPW following inoculation with native microbes. Furthermore, all residual NAs biodegraded significantly faster in ozonated OSPW. The opposite trend was found for ozonated commercial NAs, which are known to contain no significant biopersistent fraction. Thus, we suggest that ozonation preferentially degraded the most biopersistent OSPW NA fraction, and that ozonation is complementary to the biodegradation capacity of microbial populations in OSPW. The toxicity of ozonated OSPW to higher organisms needs to be assessed, but there is promise that this technique could be applied to accelerate the bioremediation of large volumes of OSPW in Northern Alberta, Canada.

Effect of water on hydrogen permeability. [Stirling engines

NASA Technical Reports Server (NTRS)

Hulligan, D. D.; Tomazic, W. A.

1984-01-01

Doping of hydrogen with CO or CO2 was developed to reduce hydrogen permeation in Stirling engines by forming low permeability oxide coatings in the heater tubes. An end product of this process is water - which can condense in the cold parts of the engine system. If the water vapor is reduced to a low enough level, the hydrogen can reduce the oxide coating resulting in increased permeability. The equilibrium level of water (oxygen bearing gas) required to avoid reduction of the oxide coating was investigated. Results at 720 C and 13.8 MPa have shown that: (1) pure hydrogen will reduce the coating; (2) 500 ppm CO (500 ppm water equivalent) does not prevent the reduction; and (3) 500 ppm CO2 (1000 ppm water) appears to be close to the equilibrium level. Further tests are planned to define the equilibrium level more precisely and to extend the data to 820 C and 3.4, 6.9, and 13.8 MPa.

Evidence for midwinter chemical ozone destruction over Antartica

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voemel, H.; Hoffmann, D.J.; Oltmans, S.J.

1995-09-01

Two ozone profiles on June 15 and June 19, obtained over McMurdo, Antartica, showed a strong depletion in stratospheric ozone, and a simultaneous profile of water vapor on June 19 showed the first clear signs of dehydration. The observation of Polar Stratospheric Clouds (PSCs) beginning with the first sounding showing ozone depletion, the indication of rehydration layers, which could be a sign for recent dehydration, and trajectory calculations indicate that the observed low ozone was not the result of transport from lower latitudes. during this time the vortex was strongly distorted, transporting PSC processed air well into sunlit latitudes wheremore » photochemical ozone destruction may have occurred. The correlation of ozone depletion and dehydration indicates that water ice PSCs provided the dominant surface for chlorine activation. An analysis of the time when the observed air masses could have formed type II PSCs for the first time limits the time scale for the observed ozone destruction to about 4 days.« less

Differential regulation of the lung endothelin system by urban particulate matter and ozone.

PubMed

Thomson, Errol; Kumarathasan, Prem; Goegan, Patrick; Aubin, Rémy A; Vincent, Renaud

2005-11-01

Periodic elevation of ambient particulate matter and ozone levels is linked to acute cardiac morbidity and mortality. Increased plasma levels of the potent vasoconstrictor endothelin (ET)-1, a prognostic indicator of cardiac mortality, have been detected in both animal models and humans after exposure to air pollutants. The lungs are the primary source of circulating ET-1, but the direct effects of individual air pollutants and their interaction in modulating the pulmonary endothelin system are unknown. Fischer-344 rats were exposed to particles (0, 5, 50 mg/m3 EHC-93), ozone (0, 0.4, 0.8 ppm), or combinations of particles and ozone for 4 h. Changes in gene expression were measured using real-time reverse transcription polymerase chain reaction immediately after exposure and following 24 h recovery in clean air. Both pollutants individually increased preproET-1, endothelin converting enzyme-1, and endothelial nitric oxide synthase mRNA levels in the lungs shortly after exposure, consistent with the concomitant increase in plasma of the 21 amino acid ET-1[1-21] peptide measured by HPLC-fluorescence. PreproET-1 mRNA remained elevated 24 h after exposure to particles but not after ozone, in line with previously documented changes of the peptide in plasma. Both pollutants transiently increased endothelin-B receptor mRNA expression, while ozone decreased endothelin-A receptor mRNA levels. Coexposure to particles plus ozone increased lung preproET-1 mRNA but not plasma ET-1[1-21], suggesting alternative processing or degradation of endothelins. This coincided with an increase in the lungs of matrix metalloproteinase-2 (MMP-2), an enzyme that cleaves bigET-1 to ET-1[1-32]. Taken together, our data indicate that ozone and particulate matter independently regulate the expression of lung endothelin system genes, but show complex toxicological interaction with respect to plasma ET-1.

Description of the surface water filtration and ozone treatment system at the Northeast Fishery Center

USDA-ARS?s Scientific Manuscript database

A water filtration and ozone disinfection system was installed at the U.S. Fish and Wildlife Service's Northeast Fishery Center in Lamar, Pennsylvania to treat a surface water supply that is used to culture sensitive and endangered fish. The treatment system first passes the surface water through dr...

Climate and Ozone Response to Increased Stratospheric Water Vapor

NASA Technical Reports Server (NTRS)

Shindell, Drew T.

2001-01-01

Stratospheric water vapor abundance affects ozone, surface climate, and stratospheric temperatures. From 30-50 km altitude, temperatures show global decreases of 3-6 K over recent decades. These may be a proxy for water vapor increases, as the Goddard Institute for Space Studies (GISS) climate model reproduces these trends only when stratospheric water vapor is allowed to increase. Observations suggest that stratospheric water vapor is indeed increasing, however, measurements are extremely limited in either spatial coverage or duration. The model results suggest that the observed changes may be part of a global, long-term trend. Furthermore, the required water vapor change is too large to be accounted for by increased production within the stratosphere, suggesting that ongoing climate change may be altering tropospheric input. The calculated stratospheric water vapor increase contributes an additional approximately equals 24% (approximately equals 0.2 W/m(exp 2)) to the global warming from well-mixed greenhouse gases over the past two decades. Observed ozone depletion is also better reproduced when destruction due to increased water vapor is included. If the trend continues, it could increase future global warming and impede stratospheric ozone recovery.

Towards Ideal NOx and CO2 Emission Control Technology for Bio-Oils Combustion Energy System Using a Plasma-Chemical Hybrid Process

NASA Astrophysics Data System (ADS)

Okubo, M.; Fujishima, H.; Yamato, Y.; Kuroki, T.; Tanaka, A.; Otsuka, K.

2013-03-01

A pilot-scale low-emission boiler system consisting of a bio-fuel boiler and plasma-chemical hybrid NOx removal system is investigated. This system can achieve carbon neutrality because the bio-fuel boiler uses waste vegetable oil as one of the fuels. The plasma-chemical hybrid NOx removal system has two processes: NO oxidation by ozone produced from plasma ozonizers and NO2 removal using a Na2SO3 chemical scrubber. Test demonstrations of the system are carried out for mixed oils (mixture of A-heavy oil and waste vegetable oil). Stable combustion is achieved for the mixed oil (20 - 50% waste vegetable oil). Properties of flue gas—e.g., O2, CO2 and NOx—when firing mixed oils are nearly the same as those when firing heavy oil for an average flue gas flow rate of 1000 Nm3/h. NOx concentrations at the boiler outlet are 90 - 95 ppm. Furthermore, during a 300-min continuous operation when firing 20% mixed oil, NOx removal efficiency of more than 90% (less than 10 ppm NOx emission) is confirmed. In addition, the CO2 reduction when heavy oil is replaced with waste vegetable oil is estimated. The system comparison is described between the plasma-chemical hybrid NOx removal and the conventional technology.

Relationship of drinking water disinfectants to plasma cholesterol and thyroid hormone levels in experimental studies.

PubMed Central

Revis, N W; McCauley, P; Bull, R; Holdsworth, G

1986-01-01

The effects of drinking water containing 2 or 15 ppm chlorine (pH 6.5 and 8.5), chlorine dioxide, and monochloramine on thyroid function and plasma cholesterol were studied because previous investigators have reported cardiovascular abnormalities in experimental animals exposed to chlorinated water. Plasma thyroxine (T4) levels, as compared to controls, were significantly decreased in pigeons fed a normal or high-cholesterol diet and drinking water containing these drinking water disinfectants at a concentration of 15 ppm (the exception was chlorine at pH 6.5) for 3 months. In most of the treatment groups, T4 levels were significantly lower following the exposure to drinking water containing the 2 ppm dose. Increases in plasma cholesterol were frequently observed in the groups with lower T4 levels. This association was most evident in pigeons fed the high-cholesterol diet and exposed to these disinfectants at a dose of 15 ppm. For example, after 3 months of exposure to deionized water or water containing 15 ppm monochloramine, plasma cholesterol was 1266 +/- 172 and 2049 +/- 212 mg/dl, respectively, a difference of 783 mg/dl. The factor(s) associated with the effect of these disinfectants on plasma T4 and cholesterol is not known. We suggest however that these effects are probably mediated by products formed when these disinfectants react with organic matter in the upper gastrointestinal tract. PMID:3456597

Detection of Greenhouse Gas Precursors from Diesel Engines Using Electrochemical and Photoacoustic Sensors

PubMed Central

Mothé, Geórgia; Castro, Maria; Sthel, Marcelo; Lima, Guilherme; Brasil, Laisa; Campos, Layse; Rocha, Aline; Vargas, Helion

2010-01-01

Atmospheric pollution is one of the worst threats to modern society. The consequences derived from different forms of atmospheric pollution vary from the local to the global scale, with deep impacts on climate, environment and human health. Several gaseous pollutants, even when present in trace concentrations, play a fundamental role in important processes that occur in atmosphere. Phenomena such as global warming, photochemical smog formation, acid rain and the depletion of the stratospheric ozone layer are strongly related to the increased concentration of certain gaseous species in the atmosphere. The transport sector significantly produces atmospheric pollution, mainly when diesel oil is used as fuel. Therefore, new methodologies based on selective and sensitive gas detection schemes must be developed in order to detect and monitor pollutant gases from this source. In this work, CO2 Laser Photoacoustic Spectroscopy was used to evaluate ethylene emissions and electrochemical analyzers were used to evaluate the emissions of CO, NOx and SO2 from the exhaust of diesel powered vehicles (rural diesel with 5% of biodiesel, in this paper called only diesel) at different engine rotation speeds. Concentrations in the range 6 to 45 ppmV for ethylene, 109 to 1,231 ppmV for carbon monoxide, 75 to 868 ppmV for nitrogen oxides and 3 to 354 ppmV for sulfur dioxide were obtained. The results indicate that the detection techniques used were sufficiently selective and sensitive to detect the gaseous species mentioned above in the ppmV range. PMID:22163437

IDENTIFICATION OF NEW DRINKING WATER DISINFECTION BY-PRODUCTS FORMED IN THE PRESENCE OF BROMIDE

EPA Science Inventory

Using a combination of mass spectrometry and infrared spectroscopy, disinfection by-products (DBPs) were identified in ozonated drinking water containing elevated bromide levels, and in ozonated water treated with secondary chlorine or chloramine. Only one brominated by-product-d...

Impact of oxidative stress and supplementation with vitamins E and C on testes morphology in rats.

PubMed

Jedlinska-Krakowska, Maria; Bomba, Grazyna; Jakubowski, Karol; Rotkiewicz, Tadeusz; Jana, Barbara; Penkowski, Aleksander

2006-04-01

The aim of the study was to verify whether an increased supply of vitamins E and C prevents the detrimental effects of ozone on the testes. The experiment was performed on 5-month-old rats exposed to ozone (0.5 ppm) for 50 days (5 h daily). Simultaneously, the animals were injected with the vitamins in 5-day intervals and at different doses (0.5, 1.5, 4.5, 5 and 15 mg of vitamin E; 0.5, 3, 9, and 50 mg of vitamin C; or both vitamins together, respectively). Gonad sections were PAS stained. In the ozonized males, depletion of germ cells occurred. In the vitamin E groups, the testes were comparable to the controls, excluding the 0.5-mg-dose vitamin E group in which perivascular fibrosis and intertubular hyalinization were observed. In the vitamin C groups, intertubular hyalinization, partial arrested spermatogenesis, and desquamation of the seminiferous epithelium appeared proportional to the vitamin dose. Additionally, premature spermiation was found at a vitamin C dose of 50-mg. In the rats injected with both vitamins, hyalinization and fibrosis appeared in addition to partial arrest of spermatogenesis and vacuolar degeneration. In conclusion, vitamin E protects against the detrimental effects of ozone in rat testes irrespective of the dose applied. This was not observed for vitamin C. Moreover, administration of higher doses of vitamin C intensified the damage to the testes caused by ozone.

Interaction Effects of Temperature and Ozone on Lung Function and Markers of Systemic Inflammation, Coagulation, and Fibrinolysis: A Crossover Study of Healthy Young Volunteers

PubMed Central

Kahle, Juliette J.; Neas, Lucas M.; Devlin, Robert B.; Case, Martin W.; Schmitt, Michael T.; Madden, Michael C.

2014-01-01

Background: Trends in climate suggest that extreme weather events such as heat waves will become more common. High levels of the gaseous pollutant ozone are associated with elevated temperatures. Ozone has been associated with respiratory diseases as well as cardiovascular morbidity and mortality and can reduce lung function and alter systemic markers of fibrinolysis. The interaction between ozone and temperature is unclear. Methods: Sixteen healthy volunteers were exposed in a randomized crossover study to 0.3 ppm ozone and clean air for 2 hr at moderate (22°C) temperature and again at an elevated temperature (32.5°C). In each case lung function was performed and blood taken before and immediately after exposure and the next morning. Results: Ozone exposure at 22°C resulted in a decrease in markers of fibrinolysis the next day. There was a 51.8% net decrease in PAI-1 (plasminogen activator inhibitor-1), a 12.1% net decrease in plasminogen, and a 17.8% net increase in D-dimer. These significantly differed from the response at 32.5°C, where there was a 44.9% (p = 0.002) and a 27.9% (p = 0.001) increase in PAI-1 and plasminogen, respectively, and a 12.5% (p = 0.042) decrease in D-dimer. In contrast, decrements in lung function following ozone exposure were comparable at both moderate and elevated temperatures (forced expiratory volume in 1 sec, –12.4% vs. –7.5%, p > 0.05). No changes in systemic markers of inflammation were observed for either temperature. Conclusion: Ozone-induced systemic but not respiratory effects varied according to temperature. Our study suggests that at moderate temperature ozone may activate the fibrinolytic pathway, while at elevated temperature ozone may impair it. These findings provide a biological basis for the interaction between temperature and ozone on mortality observed in some epidemiologic studies. Citation: Kahle JJ, Neas LM, Devlin RB, Case MW, Schmitt MT, Madden MC, Diaz-Sanchez D. 2015. Interaction effects of temperature and ozone on lung function and markers of systemic inflammation, coagulation, and fibrinolysis: a crossover study of healthy young volunteers. Environ Health Perspect 123:310–316; http://dx.doi.org/10.1289/ehp.1307986 PMID:25514459

Regulation of ozone-induced lung inflammation and injury by the β-galactoside-binding lectin galectin-3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sunil, Vasanthi R., E-mail: sunilva@pharmacy.rutgers.edu; Francis, Mary, E-mail: maryfranrutgers@gmail.com; Vayas, Kinal N., E-mail: kinalv5@gmail.com

Macrophages play a dual role in ozone toxicity, contributing to both pro- and anti-inflammatory processes. Galectin-3 (Gal-3) is a lectin known to regulate macrophage activity. Herein, we analyzed the role of Gal-3 in the response of lung macrophages to ozone. Bronchoalveolar lavage (BAL) and lung tissue were collected 24–72 h after exposure (3 h) of WT and Gal-3{sup -/-} mice to air or 0.8 ppm ozone. In WT mice, ozone inhalation resulted in increased numbers of proinflammatory (Gal-3{sup +}, iNOS{sup +}) and anti-inflammatory (MR-1{sup +}) macrophages in the lungs. While accumulation of iNOS{sup +} macrophages was attenuated in Gal-3{sup -/-}more » mice, increased numbers of enlarged MR-1{sup +} macrophages were noted. This correlated with increased numbers of macrophages in BAL. Flow cytometric analysis showed that these cells were CD11b{sup +} and consisted mainly (> 97%) of mature (F4/80{sup +}CD11c{sup +}) proinflammatory (Ly6GLy6C{sup hi}) and anti-inflammatory (Ly6GLy6C{sup lo}) macrophages. Increases in both macrophage subpopulations were observed following ozone inhalation. Loss of Gal-3 resulted in a decrease in Ly6C{sup hi} macrophages, with no effect on Ly6C{sup lo} macrophages. CD11b{sup +}Ly6G{sup +}Ly6C{sup +} granulocytic (G) and monocytic (M) myeloid derived suppressor cells (MDSC) were also identified in the lung after ozone. In Gal-3{sup -/-} mice, the response of G-MDSC to ozone was attenuated, while the response of M-MDSC was heightened. Changes in inflammatory cell populations in the lung of ozone treated Gal-3{sup -/-} mice were correlated with reduced tissue injury as measured by cytochrome b5 expression. These data demonstrate that Gal-3 plays a role in promoting proinflammatory macrophage accumulation and toxicity in the lung following ozone exposure. - Highlights: • Multiple monocytic-macrophage subpopulations accumulate in the lung after ozone inhalation. • Galectin-3 plays a proinflammatory role in ozone-induced lung injury. • In the absence of gal-3, inflammatory cells with a myeloid derived suppressor cell phenotype contribute to tissue repair.« less

Modeling coupled interactions of carbon, water, and ozone exchange between terrestrial ecosystems and the atmosphere. I: model description.

PubMed

Nikolov, Ned; Zeller, Karl F

2003-01-01

A new biophysical model (FORFLUX) is presented to study the simultaneous exchange of ozone, carbon dioxide, and water vapor between terrestrial ecosystems and the atmosphere. The model mechanistically couples all major processes controlling ecosystem flows trace gases and water implementing recent concepts in plant eco-physiology, micrometeorology, and soil hydrology. FORFLUX consists of four interconnected modules-a leaf photosynthesis model, a canopy flux model, a soil heat-, water- and CO2- transport model, and a snow pack model. Photosynthesis, water-vapor flux and ozone uptake at the leaf level are computed by the LEAFC3 sub-model. The canopy module scales leaf responses to a stand level by numerical integration of the LEAFC3model over canopy leaf area index (LAI). The integration takes into account (1) radiative transfer inside the canopy, (2) variation of foliage photosynthetic capacity with canopy depth, (3) wind speed attenuation throughout the canopy, and (4) rainfall interception by foliage elements. The soil module uses principles of the diffusion theory to predict temperature and moisture dynamics within the soil column, evaporation, and CO2 efflux from soil. The effect of soil heterogeneity on field-scale fluxes is simulated employing the Bresler-Dagan stochastic concept. The accumulation and melt of snow on the ground is predicted using an explicit energy balance approach. Ozone deposition is modeled as a sum of three fluxes- ozone uptake via plant stomata, deposition to non-transpiring plant surfaces, and ozone flux into the ground. All biophysical interactions are computed hourly while model projections are made at either hourly or daily time step. FORFLUX represents a comprehensive approach to studying ozone deposition and its link to carbon and water cycles in terrestrial ecosystems.

Effects of a modular two-step ozone-water and annealing process on silicon carbide graphene

DOE Office of Scientific and Technical Information (OSTI.GOV)

Webb, Matthew J., E-mail: matthew.webb@cantab.net; Lundstedt, Anna; Grennberg, Helena

By combining ozone and water, the effect of exposing epitaxial graphene on silicon carbide to an aggressive wet-chemical process has been evaluated after high temperature annealing in ultra high vacuum. The decomposition of ozone in water produces a number of oxidizing species, however, despite long exposure times to the aqueous-ozone environment, no graphene oxide was observed after the two-step process. The systems were comprehensively characterized before and after processing using Raman spectroscopy, core level photoemission spectroscopy, and angle resolved photoemission spectroscopy together with low energy electron diffraction, low energy electron microscopy, and atomic force microscopy. In spite of the chemicalmore » potential of the aqueous-ozone reaction environment, the graphene domains were largely unaffected raising the prospect of employing such simple chemical and annealing protocols to clean or prepare epitaxial graphene surfaces.« less

Endocrine Activities of Pesticides During Ozonation of Waters.

PubMed

Westlund, Paul; Isazadeh, Siavash; Therrien, Alexandre; Yargeau, Viviane

2018-01-01

Two yeast-based bioassays were used to assess the endocrine activity potential of transformation products formed during the ozonation of water containing a variety of pesticides (propiconazole, atrazine, 2,4-dichlorophenoxyacetic acid [2,4-D], tebuconazole, climbazole, myclobutanil, irgarol, terbutryn, dicamba, mecoprop and diuron). Ozone experiments were conducted first in reverse osmosis water to isolate the effects of the pesticides and then in synthetic wastewater and wastewater effluent to investigate whether the results translated to more complex matrices. The findings demonstrate the recalcitrant nature of most pesticides during ozonation, with removals below 50%, except for irgarol, terbutryn and climbazole with removals up to 70%. This study is the first one to investigate the removal of the fungicides myclobutanil and tebuconazole by ozonation and is one of the first studies to investigate the androgenic activity of ozonation transformation products of contaminants of emerging concern. These findings also demonstrated that during ozonation the initial anti-androgenic activity was removed while the estrogenic activity remained undetected and the androgenic activity increased to levels up to 60% of the anti-androgenic activity of the DHT control. These results indicate that bioactivity should be considered in the evaluation of treatment performance and risks assessment associated to wastewater discharges.

Pepper injury and partitioning response to ozone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennett, J.P.; Oshima, R.J.; Lippert, L.F.

Pepper plants (Capsicum annuum L.) grown in containers and exposed intermittently to 0.12 or 0.20 ppm ozone (O/sub 3/) while they grew to final yield, increased in plant height and total number of leaves in spite of the formation of chlorotic leaves. On an absolute basis, root, stem and leaf dry weights were not significantly affected by O/sub 3/, but fruit dry matter fell by as much as 54%. However, on a relative basis, dry matter partitioning to fruit was not constant and a significant alteration of the expected dry matter distribution was observed in the O/sub 3/ treatment. O/submore » 3/ also significantly accentuated the inverse relationship between crown fruit and leaf production. A conceptual model for whole plant response to O/sub 3/ was developed.« less

Ozonation of cooling tower waters

NASA Technical Reports Server (NTRS)

Humphrey, M. F.; French, K. R.; Howe, R. D. (Inventor)

1979-01-01

Continuous ozone injection into water circulating between a cooling tower and heat exchanger with heavy scale deposits inhibits formation of further deposits, promotes flaking of existing deposits, inhibits chemical corrosion and controls algae and bacteria.

Removal of disinfection by-products from contaminated water using a synthetic goethite catalyst via catalytic ozonation and a biofiltration system.

PubMed

Wang, Yu-Hsiang; Chen, Kuan-Chung

2014-09-10

The effects of synthetic goethite (α-FeOOH) used as the catalyst in catalytic ozonation for the degradation of disinfection by-product (DBP) precursors are investigated. A biofiltration column applied following the catalytic ozonation process is used to evaluate the efficiency of removing DBP precursors via biotreatment. Ozone can rapidly react with aromatic compounds and oxidize organic compounds, resulting in a decrease in the fluorescence intensity of dissolved organic matter (DOM). In addition, catalytic ozonation can break down large organic molecules, which causes a blue shift in the emission-excitation matrix spectra. Water treated with catalytic ozonation is composed of low-molecular structures, including soluble microbial products (SMPs) and other aromatic proteins (APs). The DOM in SMPs and APs is removed by subsequent biofiltration. Catalytic ozonation has a higher removal efficiency for dissolved organic carbon and higher ultraviolet absorbance at 254 nm compared to those of ozonation without a catalyst. The use of catalytic ozonation and subsequent biofiltration leads to a lower DBP formation potential during chlorination compared to that obtained using ozonation and catalytic ozonation alone. Regarding DBP species during chlorination, the bromine incorporation factor (BIF) of trihalomethanes and haloacetic acids increases with increasing catalyst dosage in catalytic ozonation. Moreover, the highest BIF is obtained for catalytic ozonation and subsequent biofiltration.

Removal of Disinfection By-Products from Contaminated Water Using a Synthetic Goethite Catalyst via Catalytic Ozonation and a Biofiltration System·

PubMed Central

Wang, Yu-Hsiang; Chen, Kuan-Chung

2014-01-01

The effects of synthetic goethite (α-FeOOH) used as the catalyst in catalytic ozonation for the degradation of disinfection by-product (DBP) precursors are investigated. A biofiltration column applied following the catalytic ozonation process is used to evaluate the efficiency of removing DBP precursors via biotreatment. Ozone can rapidly react with aromatic compounds and oxidize organic compounds, resulting in a decrease in the fluorescence intensity of dissolved organic matter (DOM). In addition, catalytic ozonation can break down large organic molecules, which causes a blue shift in the emission-excitation matrix spectra. Water treated with catalytic ozonation is composed of low-molecular structures, including soluble microbial products (SMPs) and other aromatic proteins (APs). The DOM in SMPs and APs is removed by subsequent biofiltration. Catalytic ozonation has a higher removal efficiency for dissolved organic carbon and higher ultraviolet absorbance at 254 nm compared to those of ozonation without a catalyst. The use of catalytic ozonation and subsequent biofiltration leads to a lower DBP formation potential during chlorination compared to that obtained using ozonation and catalytic ozonation alone. Regarding DBP species during chlorination, the bromine incorporation factor (BIF) of trihalomethanes and haloacetic acids increases with increasing catalyst dosage in catalytic ozonation. Moreover, the highest BIF is obtained for catalytic ozonation and subsequent biofiltration. PMID:25211774

CO-OCCURRENCE OF OZONE AND ACIDIC CLOUD WATER IN HIGH-ELEVATION FORESTS

EPA Science Inventory

A chemical climatology for high-elevation forests was estimated from ozone and cloudwater acidity data collected in the eastern United States. esides frequent ozone-only and pH-only single-pollutant episodes, both simultaneous and sequential co-occurrence of ozone and acidic clou...

HYDROXYL RADICAL/OZONE RATIOS DURING OZONATION PROCESSES. I. THE RCT CONCEPT

EPA Science Inventory

The ozonation of model systems and several natural waters was examined in bench-scale batch experiments. In addition to measuring the concentration of ozone (03), the rate of depletion of an in situ hydroxyl radical probe compound was monitored, thus providing information on the ...

Formation of assimilable organic carbon during oxidation of natural waters with ozone, chlorine dioxide, chlorine, permanganate, and ferrate.

PubMed

Ramseier, Maaike K; Peter, Andreas; Traber, Jacqueline; von Gunten, Urs

2011-02-01

Five oxidants, ozone, chlorine dioxide, chlorine, permanganate, and ferrate were studied with regard to the formation of assimilable organic carbon (AOC) and oxalate in absence and presence of cyanobacteria in lake water matrices. Ozone and ferrate formed significant amounts of AOC, i.e. more than 100 μg/L AOC were formed with 4.6 mg/L ozone and ferrate in water with 3.8 mg/L dissolved organic carbon. In the same water samples chlorine dioxide, chlorine, and permanganate produced no or only limited AOC. When cyanobacterial cells (Aphanizomenon gracile) were added to the water, an AOC increase was detected with ozone, permanganate, and ferrate, probably due to cell lysis. This was confirmed by the increase of extracellular geosmin, a substance found in the selected cyanobacterial cells. AOC formation by chlorine and chlorine dioxide was not affected by the presence of the cells. The formation of oxalate upon oxidation was found to be a linear function of the oxidant consumption for all five oxidants. The following molar yields were measured in three different water matrices based on oxidant consumed: 2.4-4.4% for ozone, 1.0-2.8% for chlorine dioxide and chlorine, 1.1-1.2% for ferrate, and 11-16% for permanganate. Furthermore, oxalate was formed in similar concentrations as trihalomethanes during chlorination (yield ∼ 1% based on chlorine consumed). Oxalate formation kinetics and stoichiometry did not correspond to the AOC formation. Therefore, oxalate cannot be used as a surrogate for AOC formation during oxidative water treatment. Copyright © 2010 Elsevier Ltd. All rights reserved.

The Observed Relationship Between Water Vapor and Ozone in the Tropical Tropopause Saturation Layer and the Influence of Meridional Transport

NASA Technical Reports Server (NTRS)

Selkirk, Henry B.; Schoeberl, M. R.; Olsen, M. A.; Douglass, A. R.

2011-01-01

We examine balloonsonde observations of water vapor and ozone from three Ticosonde campaigns over San Jose, Costa Rica [10 N, 84 W] during northern summer and a fourth during northern winter. The data from the summer campaigns show that the uppermost portion of the tropical tropopause layer between 360 and 380 K, which we term the tropopause saturation layer or TSL, is characterized by water vapor mixing ratios from proximately 3 to 15 ppmv and ozone from approximately 50 ppbv to 250 ppbv. In contrast, the atmospheric water vapor tape recorder at 380 K and above displays a more restricted 4-7 ppmv range in water vapor mixing ratio. From this perspective, most of the parcels in the TSL fall into two classes - those that need only additional radiative heating to rise into the tape recorder and those requiring some combination of additional dehydration and mixing with drier air. A substantial fraction of the latter class have ozone mixing ratios greater than 150 ppbv, and with water vapor greater than 7 ppmv this air may well have been transported into the tropics from the middle latitudes in conjunction with high-amplitude equatorial waves. We examine this possibility with both trajectory analysis and transport diagnostics based on HIRDLS ozone data. We apply the same approach to study the winter season. Here a very different regime obtains as the ozone-water vapor scatter diagram of the sonde data shows the stratosphere and troposphere to be clearly demarcated with little evidence of mixing in of middle latitude air parcels.

Ozonation kinetics of winery wastewater in a pilot-scale bubble column reactor.

PubMed

Lucas, Marco S; Peres, José A; Lan, Bing Yan; Li Puma, Gianluca

2009-04-01

The degradation of organic substances present in winery wastewater was studied in a pilot-scale, bubble column ozonation reactor. A steady reduction of chemical oxygen demand (COD) was observed under the action of ozone at the natural pH of the wastewater (pH 4). At alkaline and neutral pH the degradation rate was accelerated by the formation of radical species from the decomposition of ozone. Furthermore, the reaction of hydrogen peroxide (formed from natural organic matter in the wastewater) and ozone enhances the oxidation capacity of the ozonation process. The monitoring of pH, redox potential (ORP), UV absorbance (254 nm), polyphenol content and ozone consumption was correlated with the oxidation of the organic species in the water. The ozonation of winery wastewater in the bubble column was analysed in terms of a mole balance coupled with ozonation kinetics modeled by the two-film theory of mass transfer and chemical reaction. It was determined that the ozonation reaction can develop both in and across different kinetic regimes: fast, moderate and slow, depending on the experimental conditions. The dynamic change of the rate coefficient estimated by the model was correlated with changes in the water composition and oxidant species.

Enhanced Biocide Treatments with D-amino Acid Mixtures against a Biofilm Consortium from a Water Cooling Tower.

PubMed

Jia, Ru; Li, Yingchao; Al-Mahamedh, Hussain H; Gu, Tingyue

2017-01-01

Different species of microbes form mixed-culture biofilms in cooling water systems. They cause microbiologically influenced corrosion (MIC) and biofouling, leading to increased operational and maintenance costs. In this work, two D-amino acid mixtures were found to enhance two non-oxidizing biocides [tetrakis hydroxymethyl phosphonium sulfate (THPS) and NALCO 7330 (isothiazoline derivatives)] and one oxidizing biocide [bleach (NaClO)] against a biofilm consortium from a water cooling tower in lab tests. Fifty ppm (w/w) of an equimass mixture of D-methionine, D-leucine, D-tyrosine, D-tryptophan, D-serine, D-threonine, D-phenylalanine, and D-valine (D8) enhanced 15 ppm THPS and 15 ppm NALCO 7330 with similar efficacies achieved by the 30 ppm THPS alone treatment and the 30 ppm NALCO 7330 alone treatment, respectively in the single-batch 3-h biofilm removal test. A sequential treatment method was used to enhance bleach because D-amino acids react with bleach. After a 4-h biofilm removal test, the sequential treatment of 5 ppm bleach followed by 50 ppm D8 achieved extra 1-log reduction in sessile cell counts of acid producing bacteria, sulfate reducing bacteria, and general heterotrophic bacteria compared with the 5 ppm bleach alone treatment. The 10 ppm bleach alone treatment showed a similar efficacy with the sequential treatment of 5 ppm bleach followed by 50 ppm D8. The efficacy of D8 was found better than that of D4 (an equimass mixture of D-methionine, D-leucine, D-tyrosine, and D-tryptophan) in the enhancement of the three individual biocides against the biofilm consortium.

Enhanced Biocide Treatments with D-amino Acid Mixtures against a Biofilm Consortium from a Water Cooling Tower

PubMed Central

Jia, Ru; Li, Yingchao; Al-Mahamedh, Hussain H.; Gu, Tingyue

2017-01-01

Different species of microbes form mixed-culture biofilms in cooling water systems. They cause microbiologically influenced corrosion (MIC) and biofouling, leading to increased operational and maintenance costs. In this work, two D-amino acid mixtures were found to enhance two non-oxidizing biocides [tetrakis hydroxymethyl phosphonium sulfate (THPS) and NALCO 7330 (isothiazoline derivatives)] and one oxidizing biocide [bleach (NaClO)] against a biofilm consortium from a water cooling tower in lab tests. Fifty ppm (w/w) of an equimass mixture of D-methionine, D-leucine, D-tyrosine, D-tryptophan, D-serine, D-threonine, D-phenylalanine, and D-valine (D8) enhanced 15 ppm THPS and 15 ppm NALCO 7330 with similar efficacies achieved by the 30 ppm THPS alone treatment and the 30 ppm NALCO 7330 alone treatment, respectively in the single-batch 3-h biofilm removal test. A sequential treatment method was used to enhance bleach because D-amino acids react with bleach. After a 4-h biofilm removal test, the sequential treatment of 5 ppm bleach followed by 50 ppm D8 achieved extra 1-log reduction in sessile cell counts of acid producing bacteria, sulfate reducing bacteria, and general heterotrophic bacteria compared with the 5 ppm bleach alone treatment. The 10 ppm bleach alone treatment showed a similar efficacy with the sequential treatment of 5 ppm bleach followed by 50 ppm D8. The efficacy of D8 was found better than that of D4 (an equimass mixture of D-methionine, D-leucine, D-tyrosine, and D-tryptophan) in the enhancement of the three individual biocides against the biofilm consortium. PMID:28861053

MODELING CRYPTOSPORIDIUM PARVUM OOCYST INACTIVATION AND BROMATE IN A FLOW-THROUGH OZONE CONTACTOR TREATING NATURAL WATER

EPA Science Inventory

A reactive transport model was developed to simultaneously predict Cryptosporidium parvum oocyst inactivation and bromate formation during ozonation of natural water. A mechanistic model previously established to predict bromate formation in organic-free synthetic waters w...

IDENTIFICATION OF DRINKING WATER DISINFECTION BY-PRODUCTS FROM OZONE, CHLORINE DIOXIDE, CHLORAMINE, AND CHLORINE

EPA Science Inventory

Many drinking water treatment plants are currently using alternative disinfectants to treat drinking water, with ozone, chlorine dioxide, and chloramine being the most popular. However, compared to chlorine, which has been much more widely studied, there is little information abo...

Effects of ammonium perchlorate on the reproductive performance and thyroid follicle histology of zebrafish

USGS Publications Warehouse

Patino, R.; Wainscott, M.R.; Cruz-Li, E. I.; Balakrishnan, S.; McMurry, C.; Blazer, V.S.; Anderson, T.A.

2003-01-01

Adult zebrafish were reared up to eight weeks in control water or in water containing ammonium perchlorate (AP) at measured perchlorate concentrations of 18 (environmentally relevant, high) and 677 ppm. Groups of eight females were paired with four males on a weekly basis to assess AP effects on spawned egg volume, an index of reproductive performance. All treatments were applied to four to five spawning replicates. At 677 ppm, spawn volume was reduced within one week and became negligible after four weeks. At 18 ppm, spawn volume was unaffected even after eight weeks. Also, perchlorate at 18 ppm did not affect percentage egg fertilization. Fish were collected at the end of the exposures (677 ppm, four weeks; control and 18 ppm, eight weeks) for whole-body perchlorate content and thyroid histopathological analysis. Fish perchlorate levels were about one-hundredth of those of treatment water levels, indicating that waterborne perchlorate does not accumulate in whole fish. At 677 ppm for four weeks, perchlorate caused thyroid follicle cell (nuclear) hypertrophy and angiogenesis, whereas at 18 ppm for eight weeks, its effects were more pronounced and included hypertrophy, angiogenesis, hyperplasia, and colloid depletion. In conclusion, an eight-week exposure of adult zebrafish to 18 ppm perchlorate (high environmentally relevant concentrations) affected the histological condition of their thyroid follicles but not their reproductive performance. The effect of 677 ppm perchlorate on reproduction may be due to extrathyroidal toxicity. Further research is needed to determine if AP at lower environmentally relevant concentrations also affects the thyroid follicles of zebrafish.

Quality of Delaware River water at Trenton, New Jersey

USGS Publications Warehouse

McCarthy, Leo T.; Keighton, Walter B.

1964-01-01

Water in the Delaware River at Trenton, NJ, is a mixture of several types--water from the mountainous headwater region, water from the coal-mining regions, and water from the limestone valleys. The quantities of these types of water, in relation to the total quantity of water at Trenton, vary with changes in season and reservoir releases. The chemical quality of the water during the 17-year period 1945-61 was excellent, and the water was suitable for most uses after little or no treatment. The average concentration of dissolved solids was 86 ppm (parts per million), and 90 percent of the time it ranged from 57 to 126 ppm. Usually the pH of the water was close to 7.0 (considered to be a neutral point-neither acid nor alkaline). The hardness was less than 86 ppm 95 percent of the time. The general composition of the dissolved-solids content, in terms of equivalents, is 28 percent calcium, 14 percent magnesium, 8 percent sodium plus potassium, 43 percent bicarbonate plus sulfate, 5 percent chloride, and 2 percent nitrate. Concentrations of minerals in the river water are lowest during March, April and May (median concentration of dissolved solids 66 PPM) and are highest during August and September (median, 107 PPM). Each year an average of 880,000 tons of dissolved solids and 932,000 tons of suspended solids are carried past Trenton by the Delaware River. The greatest monthly loads of dissolved solids are in March and April, and the smallest are from July to October. Suspended-solids loads are greater when the streamflow is high but small the rest of the time. Concentration of suspended solids exceeds 100 PPM only 5 percent of the time. The headwaters in the Delaware River basin are the source of water of excellent quality. Much of this water is stored in reservoirs, and when released during August and September, it improves the quality of the water at Trenton. These releases to augment low flow have the effect of narrowing the range of concentrations of dissolved constituents. In 1952 and 1962, 6 and 19 percent, respectively, of the drainage area above Trenton was regulated by reservoirs. After proposed construction, 60 percent will be regulated by 1975. Thus, it may be that the high concentrations of dissolved constituents observed in the 1945-61 period will not occur again. It is possible that the water quality observed during the period 1945-61 (dissolved solids 57-126 PPM 90 percent of the time, pH close to 7.0, hardness less than 86 PPM 95 percent of the time) is representative of what can be expected in the future, for a variety of hydrologic conditions were experienced in the 17-year period.

Development of a hybrid ozonation biofilm-membrane filatration process for the production of drinking water.

PubMed

Leiknes, T; Lazarova, M; Odegaard, H

2005-01-01

Drinking water sources in Norway are characterized by high concentrations of natural organic matter (NOM), low alkalinity and low turbidity. The removal of NOM is therefore a general requirement in producing potable water. Drinking water treatment plants are commonly designed with coagulation direct filtration or NF spiral wound membrane processes. This study has investigated the feasibility and potential of a hybrid process combining ozonation and biofiltration with a rotating disk membrane for treating drinking water with high NOM concentrations. Ozonation will oxidize the NOM content removing colour and form biodegradable organic compounds, which can be removed in biological filters. A constructed water was used in this study which is representative of ozonated NOM-containing water. A rotating membrane disk bioreactor downstream the ozonation process was used to carry out both the biodegradation as well as biomass separation in the same reactor. Maintenance of biodegradation of the organic matter while controlling biofouling of the membrane and acceptable water production rates was the focus in the study. Three operating modes were investigated. Removal of the biodegradable organics was consistent throughout the study indicating that sufficient biomass was maintained in the reactor for all operating conditions tested. Biofouling control was not achieved through shear-induced cleaning by periodically rotating the membrane disks at high speed. By adding a small amount of sponges in the membrane chamber the biofouling could be controlled by mechanical cleaning of the membrane surface during disk rotation. The overall results indicate that the system can favorably be used in an ozonation/biofiltration process by carrying out both biodegradation as well as biomass separation in the same reactor.

Inactivation of Ichthyophonus spores using sodium hypochlorite and polyvinyl pyrrolidone iodine

USGS Publications Warehouse

Hershberger, P.K.; Pacheco, C.A.; Gregg, J.L.

2008-01-01

Chlorine and iodine solutions were effective at inactivating Ichthyophonus spores in vitro. Inactivation in sea water increased directly with halogen concentration and exposure duration, with significant differences (P < 0.05) from controls occurring at all chlorine concentrations and exposure durations tested (1.5-13.3 ppm for 1-60 min) and at most iodine concentrations and exposure durations tested (1.2 ppm for 60 min and 5.9-10.7 ppm for 1-60 min). However, 10-fold reductions in spore viability occurred only after exposure to halogen solutions at higher concentrations and/or longer durations (13 ppm total chlorine for 1-60 min, 5.9 ppm total iodine for 60 min, and 10.7 ppm total iodine for 1-60 min). Inactivation efficacy was greater when halogen solutions were prepared in fresh water, presumably because of combined effects of halogen-induced inactivation and general spore instability in fresh water. The results have practical implications for disinfection and biocontainment in research laboratories and other facilities that handle live Ichthyophonus cultures and/or infected fish.

Geographical mapping of fluoride levels in drinking water sources in Nigeria.

PubMed

Akpata, Enosakhare S; Danfillo, I S; Otoh, E C; Mafeni, J O

2009-12-01

Knowledge of fluoride levels in drinking water is of importance in dental public health, yet this information is lacking, at national level, in Nigeria. To map out fluoride levels in drinking water sources in Nigeria. Fluoride levels in drinking water sources from 109 randomly selected Local Government Areas (LGAs) in the 6 Nigerian geopolitical zones were determined. From the results, maps showing LGAs with fluoride concentrations exceeding 0.3 ppm, were drawn. ANOVA and t-test were used to determine the significance of the differences between the fluoride levels in the drinking water sources. Fluoride levels were low in most parts of the country, being 0.3 ppm or less in 62% of the LGAs. Fluoride concentrations were generally higher in North Central geopolitical zone, than the other zones in the country (p<0.05). In a few drinking water sources, fluoride concentrations exceeded 1.5 ppm, but was as high as 6.7 ppm in one well. Only 9% of the water sources were from waterworks. Most of the water sources in Nigeria contained low fluoride levels; but few had excessive concentrations and need to be partially defluoridated, or else alternative sources of drinking water provided for the community.

Survival of two bacterial fish pathogens (Aeromonas salmonicida and the Enteric Redmouth Bacterium) in ozonated, chlorinated, and untreated waters

USGS Publications Warehouse

Wedemeyer, Gary A.; Nelson, Nancy C.

1977-01-01

Ozone and chlorine inactivation curves were determined in three water types at 20 °C for the destruction of the fish pathogens Aeromonas salmonicida, the etiologic agent of furunculosis, and the enteric redmouth bacterium (ERM). In phosphate-buffered distilled water, 0.01 mg/ℓ ozone inactivated 103 cells/ml of ERM and A. salmonicida in 1/2 and 10 min, respectively. Chlorine at this concentration had little effect on either pathogen and a residual of at least 0.05 mg/ℓ was needed to achieve a complete kill within a 10-min contact time. In soft lake water (30 mg/ℓ as CaCO3) a chlorine residual of 0.1 mg/ℓ rapidly  inactivated A. salmonicida and ERM but in hard water (120 mg/ℓ) A. salmonicida was more resistant and 0.2 mg/ℓ chlorine was required. Ozonation of the two lake waters at 90 mg O3∙h−1∙ℓ−1 (equivalent to a 0.01 mg/ℓ residual in ozone demand-free water) was required to destroy both pathogens within 10 min.In untreated soft lake water 103 cells/ml of A. salmonicida survived only 2 days, while the ERM bacterium (103 cells/ml) survived even after 20 day s in soft and hard untreated lake waters.

The lethality of hot water and ozone to aquatic invasive species

USGS Publications Warehouse

Buley, Riley

2017-01-01

The spread of Aquatic Invasive Species (AIS) between the Great Lakes and Mississippi River Basin by way of the Chicago Area Waterway System (CAWS) is a pressing concern to resource managers in the Midwest region. Augmenting this spread are watercrafts traveling through the CAWS locks and dams. AIS are able to attach to boat hulls, equipment, or are present in the surrounding water during lock transfers. It has been proposed that chemically treating boats during lock transfers would be an effective way to reduce the spread of AIS. Of a range of treatments identified as candidates to do this, hot water and dissolved ozone ranked high as effective treatments causing the least amount of environmental impact. This study assessed the lethality of hot water and dissolved ozone, separately and in combination, on select AIS in a laboratory setting. Species were exposed to water temperatures ranging from 18 to 50°C, ozone concentrations ranging from 0 to 920 ORP (Oxidation-Reduction Potential), and exposure durations ranging from 10 to 60 min to find treatments capable of inducing 100% mortality. Results indicated that water at 45°C achieved 100% mortality in all species tested with a 10 min exposure. Ozone concentrations induced significant mortality to all species tested, particularly when combined with elevated temperatures.

Removal of dimethyl phthalate from water by ozone microbubbles.

PubMed

Jabesa, Abdisa; Ghosh, Pallab

2017-08-01

This work investigates the removal of dimethyl phthalate (DMP) from water using ozone microbubbles in a pilot plant of 20 dm 3 capacity. Experiments were performed under various reaction conditions to examine the effects of the initial concentration of DMP, pH of the medium, ozone generation rate, and the role of H 2 O 2 on the removal of DMP. The DMP present in water was effectively removed by the ozone microbubbles. The removal was effective in neutral and alkaline media. Increase in the initial concentration of the target pollutant negatively affected its removal efficiency. The removal efficiency dramatically increased from 1% to 99% when the ozone generation rate was increased from 0.28 to 1.94 mg s -1 at pH 7. The total organic carbon measurements revealed that a complete mineralization of DMP was achieved within 1.8 ks at the high ozone feed rate. The use of t-butyl alcohol as the hydroxyl radical scavenger confirmed that the reaction between the target organic compound and ·OH radical dominated over its direct reaction with ozone. The reaction between DMP and ozone followed an overall second-order kinetics. The volumetric mass transfer coefficient of ozone in the reacting system and the enhancement factor increased with increasing initial concentration of DMP. Very low values of Hatta number were obtained at all initial concentrations of DMP and pH, which show that the mass transfer resistance was small.

Inactivation of Template-Directed Misfolding of Infectious Prion Protein by Ozone

PubMed Central

Ding, Ning; Price, Luke M.; Braithwaite, Shannon L.; Balachandran, Aru; Belosevic, Miodrag

2012-01-01

Misfolded prions (PrPSc) are well known for their resistance to conventional decontamination processes. The potential risk of contamination of the water environment, as a result of disposal of specified risk materials (SRM), has raised public concerns. Ozone is commonly utilized in the water industry for inactivation of microbial contaminants and was tested in this study for its ability to inactivate prions (263K hamster scrapie = PrPSc). Treatment variables included initial ozone dose (7.6 to 25.7 mg/liter), contact time (5 s and 5 min), temperature (4°C and 20°C), and pH (pH 4.4, 6.0, and 8.0). Exposure of dilute suspensions of the infected 263K hamster brain homogenates (IBH) (0.01%) to ozone resulted in the in vitro destruction of the templating properties of PrPSc, as measured by the protein misfolding cyclic amplification (PMCA) assay. The highest levels of prion inactivation (≥4 log10) were observed with ozone doses of 13.0 mg/liter, at pH 4.4 and 20°C, resulting in a CT (the product of residual ozone concentration and contact time) value as low as 0.59 mg · liter−1 min. A comparison of ozone CT requirements among various pathogens suggests that prions are more susceptible to ozone degradation than some model bacteria and protozoa and that ozone treatment may be an effective solution for inactivating prions in water and wastewater. PMID:22138993

Incidence of heavy metal contamination in water supplies in northern Mexico.

PubMed

Wyatt, C J; Fimbres, C; Romo, L; Méndez, R O; Grijalva, M

1998-02-01

Contaminants in drinking water present public health risks. The objective of this study was to analyze water samples taken from wells or storage tanks, direct sources for domestic water in Northern Mexico, for the presence of lead (Pb), copper (Cu), cadmium (Cd), arsenic (As), and mercury (Hg). The samples were analyzed by atomic absorption coupled with a hydride generator or a graphite furnace. High levels of Pb (0.05-0.12 ppm) were found in Hermosillo, Guaymas, and Nacozari. Forty-three percent of the samples in Sonora exceeded the action level (0.015 ppm) established by the EPA for Pb. For As, 8.92% exceeded the limit with a range of 0.002-0.305 ppm. Several studies have indicated a possible link between As and fluoride (F) in drinking water. This study showed a positive correlation between F and As (r = 0.53, P = 0.01, and n = 116). One location in Hermosillo had 7.36 ppm of F and 0.117 ppm of As, 3.5 times the recommended F levels in drinking water and 2 times higher than the level permitted for As. Hg contamination was found in 42% of the samples. Based on the results of this study, it appears that As, Hg, and Pb contamination in the drinking water for some areas of the state of Sonora is a major concern.

Effects of water-soluble natural antioxidants on photosensitized oxidation of conjugated linoleic acid in an oil-in-water emulsion system.

PubMed

Liu, T-T; Yang, T-S

2008-05-01

The effect of photosensitized oxidation of conjugated linoleic acid in an oil-in-water (o/w) emulsion system was studied. Water-soluble natural antioxidants, including apple polyphenols from apple extract, green tea extract, 4-hydroxy-2(or 5)-ethyl-5(or2)-methyl-3(2H)-furanone(HEMF), 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF), and ascorbic acid, were tested for antioxidant activity in this system. The green tea extract showed the highest antioxidant activity followed by ascorbic acid. Apple polyphenols did not give significant antioxidant activity. HEMF and HDMF exhibited a prooxidant effect. The antioxidant activity of tea catechins was also investigated. Of them, EGCG and ECG exhibited antioxidant activity at 50 ppm, but the antioxidant activity between them was not significantly different (P < 0.05). Comparatively, EC, EGC, and GCG showed no significant antioxidative effect at 50 ppm. When the concentration increased to 100 ppm, the antioxidant activity of ECG and EGCG significantly increased compared with that at 50 ppm, and EGCG had higher antioxidant activity than ECG. GCG also showed significant antioxidant activity at 100 ppm. EGCG exhibited the highest antioxidant activity among the tea catechins in the emulsion system at 100 ppm.

MTBE OXIDATION BYPRODUCTS FROM THE TREATMENT OF SURFACE WATERS BY OZONATION AND UV-OZONATION

EPA Science Inventory

In recent years, there has been considerable concern over the release of methyl tert-butyl ether (MTBE), as gasoline additive, into the aquifers used as potable water sources. MTBE readily dissolves in water and has entered the environment via gasoline spills and leaking...

Removal of soluble microbial products as the precursors of disinfection by-products in drinking water supplies.

PubMed

Liu, Jin-Lin; Li, Xiao-Yan

2015-01-01

Water pollution worsens the problem of disinfection by-products (DBPs) in drinking water supply. Biodegradation of wastewater organics produces soluble microbial products (SMPs), which can be important DBP precursors. In this laboratory study, a number of enhanced water treatment methods for DBP control, including enhanced coagulation, ozonation, and activated carbon adsorption, were evaluated for their effectiveness in treating SMP-containing water for the DBP reduction purpose. The results show that enhanced coagulation with alum could remove SMPs only marginally and decrease the DBP formation potential (DBPFP) of the water by less than 20%. Although ozone could cause destruction of SMPs in water, the overall DBPFP of the water did not decrease but increased after ozonation. In contrast, adsorption by granular activated carbon could remove the SMP organics from water by more than 60% and reduce the DBPFP by more than 70%. It is apparent that enhanced coagulation and ozonation are not suitable for the removal of SMPs as DBP precursors from polluted water, although enhanced coagulation has been commonly used to reduce the DBP formation caused by natural organic matter. In comparison, activated carbon adsorption is shown as a more effective means to remove the SMP content from water and hence to control the wastewater-derived DBP problem in water supply.

Assess and improve the sustainability of water treatment facility using Computational Fluid Dynamics

NASA Astrophysics Data System (ADS)

Zhang, Jie; Tejada-Martinez, Andres; Lei, Hongxia; Zhang, Qiong

2016-11-01

Fluids problems in water treatment industry are often simplified or omitted since the focus is usually on chemical process only. However hydraulics also plays an important role in determining effluent water quality. Recent studies have demonstrated that computational fluid dynamics (CFD) has the ability to simulate the physical and chemical processes in reactive flows in water treatment facilities, such as in chlorine and ozone disinfection tanks. This study presents the results from CFD simulations of reactive flow in an existing full-scale ozone disinfection tank and in potential designs. Through analysis of the simulation results, we found that baffling factor and CT10 are not optimal indicators of disinfection performance. We also found that the relationship between effluent CT (the product of disinfectant concentration and contact time) obtained from CT transport simulation and baffling factor depends on the location of ozone release. In addition, we analyzed the environmental and economic impacts of ozone disinfection tank designs and developed a composite indicator to quantify the sustainability of ozone disinfection tank in technological, environmental and economic dimensions.

Fluoride contamination sensor based on optical fiber grating technology

NASA Astrophysics Data System (ADS)

Jadhav, Mangesh S.; Laxmeshwar, Lata S.; Akki, Jyoti F.; Raikar, P. U.; Kumar, Jitendra; Prakash, Om; Raikar, U. S.

2017-11-01

A number of distinct advantages of the optical fiber technology in the field of sensors and communications which leads to enormous applications. Fiber Bragg grating (FBG) developed from the fabrication of photosensitive fiber through phase mask technique is used in the present report. The designed fiber sensor used for the detection and determination of contaminants in drinking water at ppm & ppb level and it is considered as a special type of concentration sensor. The test samples of drinking water have been collected from different regions. In this paper we have calibrated the FBG sensor to detect Flouride concentration in drinking water in the range of 0.05-8 ppm. According to WHO, the normal range of fluoride content in drinking water is about 0.7 ppm to 1.5 ppm. The results for resultant spectral shifts for test samples are closely agree with standard values.

A Review of the Properties and Applications of Ozone in Endodontics: An Update

PubMed Central

Mohammadi, Zahed; Shalavi, Sousan; Soltani, Mohammad Karim; Asgary, Saeed

2013-01-01

Ozone is a triatomic molecule consisting of three oxygen atoms. It is applied to oral tissues in the forms of ozonated water, ozonated olive oil and oxygen/ozone gas. This paper presents a brief review on the chemistry of ozone as well as its medical and dental applications focusing on its use in endodontics. Ozone’s antimicrobial activity, its effect on dentin bonding, toxicity and contra-indications are also reviewed. PMID:23717326

Air pollution alters brain and pituitary endothelin-1 and inducible nitric oxide synthase gene expression.

PubMed

Thomson, Errol M; Kumarathasan, Prem; Calderón-Garcidueñas, Lilian; Vincent, Renaud

2007-10-01

Recent work suggests that air pollution is a risk factor for cerebrovascular and neurodegenerative disease. Effects of inhaled pollutants on the production of vasoactive factors such as endothelin (ET) and nitric oxide (NO) in the brain may be relevant to disease pathogenesis. Inhaled pollutants increase circulating levels of ET-1 and ET-3, and the pituitary is a potential source of plasma ET, but the effects of pollutants on the expression of ET and NO synthase genes in the brain and pituitary are not known. In the present study, Fischer-344 rats were exposed by nose-only inhalation to particles (0, 5, 50mg/m3 EHC-93), ozone (0, 0.4, 0.8 ppm), or combinations of particles and ozone for 4 h. Real-time reverse transcription polymerase chain reaction was used to measure mRNA levels in the cerebral hemisphere and pituitary 0 and 24 h post-exposure. Ozone inhalation significantly increased preproET-1 but decreased preproET-3 mRNAs in the cerebral hemisphere, while increasing mRNA levels of preproET-1, preproET-3, and the ET-converting enzyme (ECE)-1 in the pituitary. Inducible NO synthase (iNOS) was initially decreased in the cerebral hemisphere after ozone inhalation, but increased 24 h post-exposure. Particles decreased tumour necrosis factor (TNF)-alpha mRNA in the cerebral hemisphere, and both particles and ozone decreased TNF-alpha mRNA in the pituitary. Our results show that ozone and particulate matter rapidly modulate the expression of genes involved in key vasoregulatory pathways in the brain and pituitary, substantiating the notion that inhaled pollutants induce cerebrovascular effects.

Combined treatment technology based on synergism between hydrodynamic cavitation and advanced oxidation processes.

PubMed

Gogate, Parag R; Patil, Pankaj N

2015-07-01

The present work highlights the novel approach of combination of hydrodynamic cavitation and advanced oxidation processes for wastewater treatment. The initial part of the work concentrates on the critical analysis of the literature related to the combined approaches based on hydrodynamic cavitation followed by a case study of triazophos degradation using different approaches. The analysis of different combinations based on hydrodynamic cavitation with the Fenton chemistry, advanced Fenton chemistry, ozonation, photocatalytic oxidation, and use of hydrogen peroxide has been highlighted with recommendations for important design parameters. Subsequently degradation of triazophos pesticide in aqueous solution (20 ppm solution of commercially available triazophos pesticide) has been investigated using hydrodynamic cavitation and ozonation operated individually and in combination for the first time. Effect of different operating parameters like inlet pressure (1-8 bar) and initial pH (2.5-8) have been investigated initially. The effect of addition of Fenton's reagent at different loadings on the extent of degradation has also been investigated. The combined method of hydrodynamic cavitation and ozone has been studied using two approaches of injecting ozone in the solution tank and at the orifice (at the flow rate of 0.576 g/h and 1.95 g/h). About 50% degradation of triazophos was achieved by hydrodynamic cavitation alone under optimized operating parameters. About 80% degradation of triazophos was achieved by combination of hydrodynamic cavitation and Fenton's reagent whereas complete degradation was achieved using combination of hydrodynamic cavitation and ozonation. TOC removal of 96% was also obtained for the combination of ozone and hydrodynamic cavitation making it the best treatment strategy for removal of triazophos. Copyright © 2014 Elsevier B.V. All rights reserved.

Interactive effects of ozone and climate on water use, soil moisture content and streamflow in a southern Appalachian forest in the USA

Treesearch

S.B. McLaughlin; S.D. Wullschleger; G. Sun; M. Nosal

2007-01-01

Documentation of the degree and direction of effects of ozone on transpiration of canopies of mature forest trees is critically needed to model ozone effects on forest water use and growth in a warmer future climate.Patterns of sap flow in stems and soil moisture in the rooting zones of mature trees, coupled with late-season...

Comparative toxicity of two Iodophors to rainbow trout eggs

USGS Publications Warehouse

Amend, Donald F.

1974-01-01

Toxicity of Wescodyne(R) and Betadine(R) to eyed eggs was not adversely affected by water hardness (as calcium and magnesium) or by exposure periods up to 60 min. Both iodophors were much more toxic below pH 6.0 than at pH 8.0. In general Wescodyne was slightly more toxic than Betadine. Significant egg loss occurred if freshly fertilized eggs were water-hardened in either iodophor at 100 ppm of iodine, but egg loss at 25 ppm of iodine or at 100 ppm if the eggs were disinfected 30 min after water hardening was comparable to the control. Also, there was no effect on the egg mortality or fry development following single or multiple exposures after eggs were water hardened. At pH 6.0 and above, Wescodyne and Betadine at 100 ppm iodine in a 15-min dip would be safe to use on rainbow trout eggs at any stage of development after water hardening. Recommendations and precautions for hatchery use are given.

Fluoride Consumption and Its Impact on Oral Health

PubMed Central

Jiménez-Farfán, María Dolores; Hernández-Guerrero, Juan Carlos; Juárez-López, Lilia Adriana; Jacinto-Alemán, Luis Fernando; de la Fuente-Hernández, Javier

2011-01-01

Objective The purpose of this study was to evaluate caries and dental fluorosis among Mexican preschoolers and school-aged children in a non-endemic zone for fluorosis and to measure its biological indicators. Methods DMFT, DMFS, dmft, dmfs, and CDI indexes were applied. Fluoride urinary excretion and fluoride concentrations in home water, table salt, bottled water, bottled drinks, and toothpaste were determined. Results Schoolchildren presented fluorosis (CDI = 0.96) and dental caries (DMFT = 2.64 and DMFS = 3.97). Preschoolers presented dmft = 4.85 and dmfs = 8.80. DMFT and DMFS were lower in children with mild to moderate dental fluorosis (DF). Variable fluoride concentrations were found in the analyzed products (home water = 0.18–0.44 ppm F, table salt = 0–485 ppm F, bottled water = 0.18–0.47 ppm F, juices = 0.08–1.42 ppm F, nectars = 0.07–1.30 ppm F, bottled drinks = 0.10–1.70 ppm F, toothpaste = 0–2,053 ppm F). Mean daily fluoride excretion was 422 ± 176 μg/24 h for schoolchildren and 367 ± 150 μg/24 h for preschoolers. Conclusions Data from our study show that, despite values of excretion within an optimal fluoride intake range, the prevalence of caries was significant in both groups, and 60% of the 11- to 12-year-old children presented with dental fluorosis. In addition, variable fluoride concentrations in products frequently consumed by children were found. PMID:21318021

METHODS FOR PEROXIDES

EPA Science Inventory

The application of ozone as an alternative disinfectant for drinking water treatment has received increased attention in recent years. Ozone offers advantages for water treatment such as removal of taste and odor compounds, some dissolved inorganics and even color, which makes i...

Ozone treatment of coal- and coffee grounds-based active carbons: Water vapor adsorption and surface fractal micropores

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsunoda, Ryoichi; Ozawa, Takayoshi; Ando, Junichi

1998-09-15

Characteristics of the adsorption iostherms of water vapor on active carbons from coal and coffee grounds and those ozonized ones from the surface fractal dimension analysis are discussed. The upswing of the adsorption isotherms in the low relative pressure of coffee grounds-based active carbon, of which isotherms were not scarcely affected on ozonization, was attributed to the adsorption of water molecules on the metallic oxides playing the role of oxygen-surface complexes, which formed the corrugated surfaces on the basal planes of micropore walls with the surface fractal dimension D{sub s} > 2. On the other hand, coal-based active carbon withmore » D{sub s} < 2, which indicated the flat surfaces of micropore walls, showed little effect on the upswing even on ozonization, even though the adsorption amounts of water vapor were increased in the low relative pressure.« less

Cardiovascular protection of deep-seawater drinking water in high-fat/cholesterol fed hamsters.

PubMed

Hsu, Chin-Lin; Chang, Yuan-Yen; Chiu, Chih-Hsien; Yang, Kuo-Tai; Wang, Yu; Fu, Shih-Guei; Chen, Yi-Chen

2011-08-01

Cardiovascular protection of deep-seawater (DSW) drinking water was assessed using high-fat/cholesterol-fed hamsters in this study. All hamsters were fed a high-fat/cholesterol diet (12% fat/0.2% cholesterol), and drinking solutions were normal distiled water (NDW, hardness: 2.48ppm), DSW300 (hardness: 324.5ppm), DSW900 (hardness: 858.5ppm), and DSW1500 (hardness: 1569.0ppm), respectively. After a 6-week feeding period, body weight, heart rates, and blood pressures of hamsters were not influenced by DSW drinking waters. Serum total cholesterol (TC), triacylglycerol (TAG), atherogenic index, and malondialdehyde (MDA) levels were decreased (p<0.05) in the DSW-drinking-water groups, as compared to those in the NDW group. Additionally, increased (p<0.05) serum Trolox equivalent antioxidant capacity (TEAC), and faecal TC, TAG, and bile acid outputs were measured in the DSW-drinking-water groups. Hepatic low-density-lipoprotein receptor (LDL receptor) and cholesterol-7α-hydroxylase (CYP7A1) gene expressions were upregulated (p<0.05) by DSW drinking waters. These results demonstrate that DSW drinking water benefits the attenuation of high-fat/cholesterol-diet-induced cardiovascular disorders in hamsters. Copyright © 2011 Elsevier Ltd. All rights reserved.

Validation of Alternative to Ozone-Depleting Chemicals Used in Oxygen Line Cleaning

DTIC Science & Technology

2006-07-01

concentration in air purge stream is continuously below 600 ppm ASTM G88 Leak testing B-1B mock-up and actual 2.9 To be determined from system...to determine the effectiveness of the solvent: the solvent chosen, its concentration , and the shear stress exerted on the surface by the cleaning...operators must be trained in its use. 11 3.0 DEMONSTRATION DESIGN 3.1 PERFORMANCE OBJECTIVES The objective for this project was to produce a

Mutagenic activity of disinfection by-products

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cognet, L.; Courtois, Y.; Mallevialle, J.

1986-11-01

Data on raw water quality, disinfection treatment practices, and the resulting mutagenic properties of the treated water were compiled from pilot- and full-scale treatment experiments to evaluate that parameter which might produce variability in the results of a mutagenic study. Analysis of the data and comparison of treatment practices indicated that the measured mutagenic activity is strongly related to the characteristics of the organic matter in the raw water, the methodology used to sample and detect mutagens, the scale of the study both in terms of treatment flow and period of study, and the point at which and the conditionsmore » under which oxidants are added during treatment. Conclusions regarding disinfection systems in full-scale water treatment plants include the following: When raw water is pretreated and high concentrations of organics are present in the raw water, both ozonation and chlorination increased mutagenic activity. However, no significant difference in mutagenicity was found between the two oxidants. Both in the case of a nitrified groundwater and a clarified surface water, the mutagenic activity of the water after ozonation was related to its mutagenic activity before ozonation. With ozonation, mutagenic activity decreased after granular activated carbon (GAC) filtration. Thus, when GAC filtration follows ozone disinfection, early addition of oxidants may not be deleterious to the finished water quality. When chlorine or chlorine dioxide is added after GAC filtration, chlorine dioxide was found to produce a less mutagenic water than chlorine. Although these conclusions suggest means of controlling mutagenic activity during treatment, it must be stressed that the measurement of mutagenicity is a presumptive index of contamination level.« less

Efficacy of detergents and fresh produce disinfectants against microorganisms associated with mixed raw vegetables.

PubMed

Samadi, Nasrin; Abadian, Neda; Bakhtiari, Donya; Fazeli, Mohammad Reza; Jamalifar, Hossein

2009-07-01

Efficacy of commercial detergent and disinfectants to eliminate microorganisms associated with fresh vegetables eaten raw in Iran, including radish, parsley, basil, coriander (cilantro), Allium porrum (leek), and peppermint were studied. The raw vegetables were subjected to a triple wash treatment of washing in tap water for mud removal, washing in water containing a detergent (dishwashing liquid) or disinfectant individually, and rinsing in tap water. The population of total mesophilic microbes on the surface of untreated vegetables ranged from 10(5) to 10(6) CFU/g. Washing in tap water or treatment with detergent (333 ppm for 10 min) or benzalkonium chloride (92 ppm for 15 min) reduced the total microbial count, most probable number (MPN) of coliforms, MPN of fecal coliforms, and MPN of fecal streptococci by about 1.2 to 2.3 log. No significant differences in microbial populations were found on vegetables after decontamination with tap water, detergent, or benzalkonium chloride (P > 0.05). Treatments with peracetic acid (100 ppm for 15 min) and hydrogen peroxide (133 ppm for 30 min) reduced the total mesophilic microbial counts by about 2.8 log. The microbial reductions with calcium hypochlorite (300 ppm for 15 min) and combined hydrogen peroxide and silver ion (133 ppm for 30 min) were significantly higher than those obtained after rinsing in tap water or after detergent or benzalkonium chloride wash (P < 0.05). Pretreatment with detergent slightly enhanced the efficacy of all decontamination treatments, but results were not significantly different from those obtained after individual application of disinfectants.

Pivotal role of IL-6 in the hyperinflammatory responses to subacute ozone in adiponectin-deficient mice

PubMed Central

Kim, Hye Y.; Mathews, Joel A.; Verbout, Norah G.; Williams, Alison S.; Wurmbrand, Allison P.; Ninin, Fernanda M. C.; Neto, Felippe L.; Benedito, Leandro A. P.; Hug, Christopher; Umetsu, Dale T.; Shore, Stephanie A.

2013-01-01

Adiponectin is an adipose-derived hormone with anti-inflammatory activity. Following subacute ozone exposure (0.3 ppm for 24–72 h), neutrophilic inflammation and IL-6 are augmented in adiponectin-deficient (Adipo−/−) mice. The IL-17/granulocyte colony-stimulating factor (G-CSF) axis is required for this increased neutrophilia. We hypothesized that elevated IL-6 in Adipo−/− mice contributes to their augmented responses to ozone via effects on IL-17A expression. Therefore, we generated mice deficient in both adiponectin and IL-6 (Adipo−/−/IL-6−/−) and exposed them to ozone or air. In ozone-exposed mice, bronchoalveolar lavage (BAL) neutrophils, IL-6, and G-CSF, and pulmonary Il17a mRNA expression were greater in Adipo−/− vs. wild-type mice, but reduced in Adipo−/−/IL-6−/− vs. Adipo−/− mice. IL-17A+ F4/80+ cells and IL-17A+ γδ T cells were also reduced in Adipo−/−/IL-6−/− vs. Adipo−/− mice exposed to ozone. Only BAL neutrophils were reduced in IL-6−/− vs. wild-type mice. In wild-type mice, IL-6 was expressed in Gr-1+F4/80−CD11c− cells, whereas in Adipo−/− mice F4/80+CD11c+ cells also expressed IL-6, suggesting that IL-6 is regulated by adiponectin in these alveolar macrophages. Transcriptomic analysis identified serum amyloid A3 (Saa3), which promotes IL-17A expression, as the gene most differentially augmented by ozone in Adipo−/− vs. wild-type mice. After ozone, Saa3 mRNA expression was markedly greater in Adipo−/− vs. wild-type mice but reduced in Adipo−/−/IL-6−/− vs. Adipo−/− mice. In conclusion, our data support a pivotal role of IL-6 in the hyperinflammatory condition observed in Adipo−/− mice after ozone exposure and suggest that this role of IL-6 involves its ability to induce Saa3, IL-17A, and G-CSF. PMID:24381131

Editor's Highlight: Role of Spleen-Derived Macrophages in Ozone-Induced Lung Inflammation and Injury.

PubMed

Francis, Mary; Sun, Richard; Cervelli, Jessica A; Choi, Hyejeong; Mandal, Mili; Abramova, Elena V; Gow, Andrew J; Laskin, Jeffrey D; Laskin, Debra L

2017-01-01

Macrophages and inflammatory mediators have been implicated in ozone toxicity. In these studies, we used splenectomized (SPX) mice to assess the contribution of splenic monocytes to pulmonary inflammation and injury induced by ozone. Cells and tissue were collected 24-72 h after exposure of mice to air or ozone (0.8 ppm, 3 h). Following ozone exposure, increased numbers of pro-inflammatory CD11b  +  Ly6C Hi and anti-inflammatory CD11b  +  Ly6C Lo monocytes were observed in spleens of control (CTL) mice. CD11b  +  Ly6C Hi and MMP-9 +  pro-inflammatory macrophages were also observed in lungs of CTL mice after ozone, along with CD11b  +  Ly6C Lo and mannose receptor (MR) + anti-inflammatory macrophages. This was accompanied by increased lung expression of proteins involved in monocyte/macrophage trafficking including CCL3, CCL4, CCR1, and AT1R. Splenectomy resulted in decreases in pro-inflammatory macrophages in the lung and down regulation of CCR2, CCL2, and CCL4, but increases in CD11b  +  Ly6C Lo anti-inflammatory macrophages. CD11b + Ly6G + Ly6C + granulocytic (G)- and monocytic (M)-myeloid derived suppressor cells (MDSC)s were also detected in the lungs and spleens of CTL mice; these increased after ozone exposure. Splenectomy was associated with a decrease in G-MDSCs in the lung, with no effect on M-MDSCs. Changes in lung macrophage subpopulations and MDSCs in SPX mice were correlated with reduced ozone toxicity, as measured by decreases in bronchoalveolar lavage protein content and reduced 4-hydroxynonenal expression in the lung. These data suggest that the spleen is a source of pro-inflammatory/cytotoxic macrophages that contribute to ozone-induced lung injury, inflammation, and oxidative stress. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Efficacy of combination of ozonated water with oil for treatment of tinea pedis.

PubMed

Lu, Jianyun; Guo, Min; Ligui, Hongfa; Wu, Kathy; Xiang, Yaping; Huang, Jinhua; Gao, Lihua

2018-02-28

To evaluate efficacy of combined therapy with ozonated water and oil on patients with tinea pedis.
 Methods: A total of 60 patients with tinea pedis were divided into 2 groups in a randomized and blinded test. Patients in a control group were treated with naftinfine hydrochloride and ketoconazole cream once a day. Patients in an ozone group were treated with ozonated water bath and then ozonated oil topical application once a day. Patients in the 2 groups were treated for 4 weeks. Clinical and laboratory data were collected for both groups at the end of the 1st week, the 2nd week, and the 4th week. The Pearson chi-square was performed to compare scores of the clinical signs and symptoms (CSS) and the mycological result between the 2 groups. Independent samples T-test was performed to compare the curative effect between the 2 groups.
 Results: After 4 weeks' treatment, 6 patients were positive in the control group determined by mycological examination while 1 patient was positive in the ozone group, with no significant difference between the 2 groups (P>0.05). Changes in CSS at the end of the 1st week, 2nd week, and 4th week were obtained and showed no significant difference between the 2 groups at the 3 different time points (P>0.05). No side effects were observed.
 Conclusion: Combination of ozonated water with oil is effective on treatment of tinea pedis and it shows no side effects.

Coagulation and oxidation for controlling ultrafiltration membrane fouling in drinking water treatment: Application of ozone at low dose in submerged membrane tank.

PubMed

Yu, Wenzheng; Graham, Nigel J D; Fowler, Geoffrey D

2016-05-15

Coagulation prior to ultrafiltration (UF) is widely applied for treating contaminated surface water sources for potable supply. While beneficial, coagulation alone is unable to control membrane fouling effectively in many cases, and there is continuing interest in the use of additional, complementary methods such as oxidation in the pre-treatment of raw water prior to UF. In this study, the application of ozone at low dose in the membrane tank immediately following coagulation has been evaluated at laboratory-scale employing model raw water. In parallel tests with and without the application of ozone, the impact of applied ozone doses of 0.5 mg L(-1) and 1.5 mg L(-1) (approximately 0.18 mg L(-1) and 0.54 mg L(-1) consumed ozone, respectively) on the increase of trans-membrane pressure (TMP) was evaluated and correlated with the quantity and nature of membrane deposits, both as a cake layer and within membrane pores. The results showed that a dose of 0.5 mgO3 L(-1) gave a membrane fouling rate that was substantially lower than without ozone addition, while a dose of 1.5 mgO3 L(-1) was able to prevent fouling effects significantly (no increase in TMP). Ozone was found to decrease the concentration of bacteria (especially the concentration of bacteria per suspended solid) in the membrane tank, and to alter the nature of dissolved organic matter by increasing the proportion of hydrophilic substances. Ozone decreased the concentration of extracellular polymeric substances (EPS), such as polysaccharides and proteins, in the membrane cake layer; the reduced EPS and bacterial concentrations resulted in a much thinner cake layer, although the suspended solids concentration was much higher in the ozone added membrane tank. Ozone also decreased the accumulation and hydrophobicity of organic matter within the membrane pores, leading to minimal irreversible fouling. Therefore, the application of low-dose ozone within the UF membrane tank is a potentially important approach for fully mitigating membrane fouling. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Ozone and biofiltration as an alternative to reverse osmosis for removing PPCPs and micropollutants from treated wastewater.

PubMed

Lee, Carson O; Howe, Kerry J; Thomson, Bruce M

2012-03-15

This pilot-scale research project investigated and compared the removal of pharmaceuticals and personal care products (PPCPs) and other micropollutants from treated wastewater by ozone/biofiltration and reverse osmosis (RO). The reduction in UV254 absorbance as a function of ozone dose correlated well with the reduction in nonbiodegradable dissolved organic carbon and simultaneous production of biodegradable dissolved organic carbon (BDOC). BDOC analyses demonstrated that ozone does not mineralize organics in treated wastewater and that biofiltration can remove the organic oxidation products of ozonation. Biofiltration is recommended for treatment of ozone contactor effluent to minimize the presence of unknown micropollutant oxidation products in the treated water. Ozone/biofiltration and RO were compared on the basis of micropollutant removal efficiency, energy consumption, and waste production. Ozone doses of 4-8 mg/L were nearly as effective as RO for removing micropollutants. When wider environmental impacts such as energy consumption, water recovery, and waste production are considered, ozone/biofiltration may be a more desirable process than RO for removing PPCPs and other trace organics from treated wastewater. Copyright © 2011 Elsevier Ltd. All rights reserved.

Advanced oxidation-based treatment of furniture industry wastewater.

PubMed

Tichonovas, Martynas; Krugly, Edvinas; Grybauskas, Arturas; Jankūnaitė, Dalia; Račys, Viktoras; Martuzevičius, Dainius

2017-07-16

The paper presents a study on the treatment of the furniture industry wastewater in a bench scale advanced oxidation reactor. The researched technology utilized a simultaneous application of ozone, ultraviolet radiation and surface-immobilized TiO 2 nanoparticle catalyst. Various combinations of processes were tested, including photolysis, photocatalysis, ozonation, catalytic ozonation, photolytic ozonation and photocatalytic ozonation were tested against the efficiency of degradation. The efficiency of the processes was primarily characterized by the total organic carbon (TOC) analysis, indicating the remaining organic material in the wastewater after the treatment, while the toxicity changes in wastewater were researched by Daphnia magna toxicity tests. Photocatalytic ozonation was confirmed as the most effective combination of processes (99.3% of TOC reduction during 180 min of treatment), also being the most energy efficient (4.49-7.83 MJ/g). Photocatalytic ozonation and photolytic ozonation remained efficient across a wide range of pH (3-9), but the pH was an important factor in photocatalysis. The toxicity of wastewater depended on the duration of the treatment: half treated water was highly toxic, while fully treated water did not possess any toxicity. Our results indicate that photocatalytic ozonation has a high potential for the upscaling and application in industrial settings.

Is There Evidence that Mid-Latitude Stratospheric Ozone Depletion Occurs in Conjunction with North American Monsoon Convection?

NASA Astrophysics Data System (ADS)

Rosenlof, K. H.; Ray, E. A.; Portmann, R. W.

2017-12-01

A recent study suggests that during the period of the summertime North American Monsoon (NAM), ozone depletion could occur as a result of catalytic ozone destruction associated with the cold and wet conditions caused by overshooting convection. Aura Microwave Limb Sounder (MLS) water vapor measurements do show that the NAM region is wetter than other parts of the globe in regards to both the mean and extremes. However, definitive evidence of ozone depletion occurring in that region has not been presented. In this study, we examine coincident measurements of water vapor, ozone, and tropospheric tracers from aircraft data taken during the Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) aircraft campaign looking specifically for ozone depletion in regions identified as impacted by overshooting convection. Although we do find evidence of lower ozone values in air impacted by convective overshoots, using tropospheric tracers we attribute those observations to input of tropospheric air rather than catalytic ozone destruction. Additionally, we explore the consequences of these lower ozone values on surface UV, and conclude that there is minimal impact on the UV index.

Management of Chronic Periodontitis Using Subgingival Irrigation of Ozonized Water: A Clinical and Microbiological Study.

PubMed

Issac, Annie V; Mathew, Jayan Jacob; Ambooken, Majo; Kachappilly, Arun Jose; Pk, Ajithkumar; Johny, Thomas; Vk, Linith; Samuel, Anju

2015-08-01

Adjunctive use of professional subgingival irrigation with scaling and root planing (SRP) has been found to be beneficial in eradicating the residual microorganisms in the pocket. To evaluate the effect of ozonized water subgingival irrigation on microbiologic parameters and clinical parameters namely Gingival index, probing pocket depth, and clinical attachment level. Thirty chronic periodontitis patients with probing pocket depth ≥6mm on at least one tooth on contra lateral sides of opposite arches were included in the study. The test sites were subjected to ozonized water subgingival irrigation with subgingival irrigation device fitted with a modified subgingival tip. Control sites were subjected to scaling and root planing only. The following clinical parameters were recorded initially and after 4 weeks at the test sites and control sites. Plaque Index, Gingival Index, probing pocket depth, clinical attachment level. Microbiologic sampling was done for the test at the baseline, after scaling, immediately after ozonized water subgingival irrigation and after 4 weeks. In control sites microbiologic sampling was done at the baseline, after scaling and after 4 weeks. The following observations were made after 4 weeks. The results were statistically analysed using independent t-test and paired t-test. Test sites showed a greater reduction in pocket depth and gain in clinical attachment compared to control sites. The total anaerobic counts were significantly reduced by ozonized water subgingival irrigation along with SRP compared to SRP alone. Ozonized water subgingival irrigation can improve the clinical and microbiological parameters in patients with chronic periodontitis when used as an adjunct to scaling and root planing.

Study on an integrated process combining ozonation with ceramic ultra-filtration for decentralized supply of drinking water.

PubMed

Zhu, Jia; Fan, Xiao J; Tao, Yi; Wei, De Q; Zhang, Xi H

2014-09-19

An integrated process was specifically developed for the decentralized supply of drinking water from micro-polluted surface water in the rural areas of China. The treatment process combined ozonation with ceramic ultra-filtration (UF), coagulation for pre-treatment and granular activated carbon filtration. A flat-sheet ceramic membrane was used with a cut-off of 60 nm and the measurement of 254 mm (length) × 240 mm (width) × 6 mm (thickness). Ozonation and ceramic UF was set up whthin one reactor. The experimental results showed that the removal efficiencies of the dissolved organic carbon (DOC) and the formation potential of trihalomethanes (THMs), haloacetic acids (HAAs) and ammonia were 80%, 76%, 70% and 90%, respectively; that the turbidity of the product water was below 0.2 NTU and the particle count number (particles larger than 2 μm) was less than 50 counts per mL. The result also showed that all the pathogenic microorganisms were retained by the ceramic and that UF. Ozonation played a critical role in the control of membrane fouling and the removal of contaminants. Exactly, the membrane fouling can be controlled in situ with 3 mg L(-1) ozone at the permeate flux of 80 L m(-2) h(-1), yet the required dosage of ozone was dependent on the quality of the raw water. Therefore, this study is able to provide a highly compacted system for decentralized supply of high-quality drinking water in terms of both chemical and microbiological safety for the rural areas in China.

Comparison of tropospheric ozone profiles measured by lidars simultaneously over land and water during the 2017 NASA OWLETS campaign

NASA Astrophysics Data System (ADS)

Gronoff, G.; Sullivan, J.; Berkoff, T.; Carrion, W.; Farris, B.

2017-12-01

The NASA Langley Mobile Ozone Lidar (LMOL) and NASA Goddard's lidar (TROPOZ) have routinely measured tropospheric ozone profiles in support of various NASA campaigns and local field studies since 2013 (e.g. DISCOVER-AQ 2014). They are both charter members of the NASA Tropospheric Lidar Network (TOLNet) and were constructed within transportable containers, allowing for observations directly within a variety of complex environments. To gain a better understanding of ozone's interactions close to the surface, both of these instruments have recently designed and optimized near field optical elements for ozone detection. One of the major difficulties for the modeling and satellite communities are the sharp transition regions, both horizontal and vertical, such as the land-water gradients in O3 near coastal/urban regions that are driven by differences in surface deposition, boundary layer height, and cloud coverage.To better understand these gradients, both lidars were deployed in the Hampton Roads / Tidewater region, in Virginia, in July-August 2017, in the context of the OWLETS (Ozone Water Land Environment Transition Study) campaign. The TROPOZ lidar was deployed above land at NASA LaRC, while the LMOL lidar was deployed on the Chesapeake Bay Bridge Tunnel third island, being de-facto an over-water lidar. The distance between the two lidars was approximately 30 km. Strong differences between the two lidars measurements were observed. Some influence of the ship traffic can be seen over water, but does not affect the observations above 300m. Overall, some important discrepancies between the modeling and the lidar observations over water were found. These results shows the importance of making more measurements over water to better constrain pollution models.

Efficacy of chlorine, acidic electrolyzed water and aqueous chlorine dioxide solutions to decontaminate Escherichia coli O157:H7 from lettuce leaves.

PubMed

Keskinen, Lindsey A; Burke, Angela; Annous, Bassam A

2009-06-30

This study compared the efficacy of chlorine (20-200 ppm), acidic electrolyzed water (50 ppm chlorine, pH 2.6), acidified sodium chlorite (20-200 ppm chlorite ion concentration, Sanova), and aqueous chlorine dioxide (20-200 ppm chlorite ion concentration, TriNova) washes in reducing populations of Escherichia coli O157:H7 on artificially inoculated lettuce. Fresh-cut leaves of Romaine or Iceberg lettuce were inoculated by immersion in water containing E. coli O157:H7 (8 log CFU/ml) for 5 min and dried in a salad spinner. Leaves (25 g) were then washed for 2 min, immediately or following 24 h of storage at 4 degrees C. The washing treatments containing chlorite ion concentrations of 100 and 200 ppm were the most effective against E. coli O157:H7 populations on Iceberg lettuce, with log reductions as high as 1.25 log CFU/g and 1.05 log CFU/g for TriNova and Sanova wash treatments, respectively. All other wash treatments resulted in population reductions of less than 1 log CFU/g. Chlorine (200 ppm), TriNova, Sanova, and acidic electrolyzed water were all equally effective against E. coli O157:H7 on Romaine, with log reductions of approximately 1 log CFU/g. The 20 ppm chlorine wash was as effective as the deionized water wash in reducing populations of E. coli O157:H7 on Romaine and Iceberg lettuce. Scanning electron microscopy indicated that E. coli O157:H7 that was incorporated into biofilms or located in damage lettuce tissue remained on the lettuce leaf, while individual cells on undamaged leaf surfaces were more likely to be washed away.

Detection of trace amount of arsenic in groundwater by laser-induced breakdown spectroscopy and adsorption

NASA Astrophysics Data System (ADS)

Haider, A. F. M. Y.; Hedayet Ullah, M.; Khan, Z. H.; Kabir, Firoza; Abedin, K. M.

2014-03-01

LIBS technique coupled with adsorption has been applied for the efficient detection of arsenic in liquid. Several adsorbents like tea leaves, bamboo slice, charcoal and zinc oxide have been used to enable sensitive detection of arsenic presence in water using LIBS. Among these, zinc oxide and charcoal show the better results. The detection limits for arsenic in water were 1 ppm and 8 ppm, respectively, when ZnO and charcoal were used as adsorbents of arsenic. To date, the determination of 1 ppm of As in water is the lowest concentration of detected arsenic in water by the LIBS technique. The detection limit of As was lowered to even less than 100 ppb by a combination of LIBS technique, adsorption by ZnO and concentration enhancement technique. Using the combination of these three techniques the ultimate concentration of arsenic was found to be 0.083 ppm (83 ppb) for arsenic polluted water collected from a tube-well of Farajikandi union (longitude 90.64°, latitude 23.338° north) of Matlab Upozila of Chandpur district in Bangladesh. This result compares fairly well with the finding of arsenic concentration of 0.078 ppm in the sample by the AAS technique at the Bangladesh Council of Scientific and Industrial Research (BCSIR) lab. Such a low detection limit (1 ppm) of trace elements in liquid matrix has significantly enhanced the scope of LIBS as an analytical tool.

A kinetic study of 3-chlorophenol enhanced hydroxyl radical generation during ozonation.

PubMed

Utsumi, Hideo; Han, Youn-Hee; Ichikawa, Kazuhiro

2003-12-01

Hydroxyl (OH) radical is proposed as an important factor in the ozonation of water. In the present study, the enhancing effect of 3-chlorophenol on OH radical generation was mathematically evaluated using electron spin resonance (ESR)/spin-trapping technique. OH radical was trapped with a 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a stable adduct, DMPO-OH. The initial velocity of DMPO-OH generation in ozonated water containing 3-chlorophenol was quantitatively measured using a combined system of ESR spectroscopy with stopped-flow apparatus which was controlled by home-made software. The initial velocity of DMPO-OH generation increased as a function of the concentration of ozone and the more effectively of 3-chlorophenol concentration. The relation among ozone concentration, amount of 3-chlorophenol and the initial velocity (nu(0)) of DMPO-OH generation was mathematically analyzed and the following equation was obtained, nu(0) (10(-6)M/s)=[9.7 x [3-chlorophenol (10(-9)M)] + 0.0005]exp(57 x [ozone (10(-9)M)]). The equation fitted very well with the experimental results, and the correlation coefficient was larger than 0.99. The equation for the enhancing effect by 3-chlorophenol should provide useful information to optimize the condition in ozone treatment process of water containing phenolic pollutants.

Ozonation catalyzed by the raw bauxite for the degradation of 2,4,6-trichloroanisole in drinking water.

PubMed

Qi, Fei; Xu, Bingbing; Chen, Zhonglin; Ma, Jun; Sun, Dezhi; Zhang, Liqiu; Wu, Fengchang

2009-08-30

A kind of inexpensive and environmental friendly mineral, the raw bauxite has been used successfully as a catalyst combined with ozonation in the degradation of 2,4,6-trichloroanisole (TCA). The catalyst was characterized by using various analytical techniques. X-ray powder diffraction (XRD) characterization showed that the raw bauxite containing boehmite (gamma-AlOOH), kaolinite (Al(2)Si(2)O(5)(OH)(4)) and quartz (SiO(2)), and gamma-AlOOH was the major composition. The catalytic ozonation removal effectiveness of TCA was investigated under various physicochemical conditions. Both the adsorption and the single ozonation were not effective for the degradation of TCA, and the presence of the raw bauxite in ozonation enhanced the TCA removal effectiveness. Both the hydroxyl radicals (OH) scavenging experiment and R(ct) characterization confirmed that the generation of OH was accounted for the enhancement of the degradation of TCA. The generation of OH was inhibited faintly by the presence of both natural organic matters (NOMs) and alkalinity in the natural water during catalyzed ozonation with the raw bauxite. The increasing of both the bauxite dosage and the ozone dosage enhanced the removal effectiveness of TCA. The raw bauxite was an efficient green catalyst for TCA degradation in drinking water.

Characterization of N-nitrosodimethylamine formation from the ozonation of ranitidine.

PubMed

Lv, Juan; Wang, Lin; Li, Yongmei

2017-08-01

N-nitrosodimethylamine (NDMA) is an emerging disinfection by-product which is formed during water disinfection in the presence of amine-based precursors. Ranitidine, as one kind of amine-based pharmaceuticals, has been identified as NDMA precursor with high NDMA molar conversion during chloramination. This study focused on the characterization of NDMA formation during ozonation of ranitidine. Influences of operational variables (ozone dose, pH value) and water matrix on NDMA generation as well as ranitidine degradation were evaluated. The results indicate high reactivity of ranitidine with ozone. Dimethylamine (DMA) and NDMA were generated due to ranitidine oxidation. High pH value caused more NDMA accumulation. NDMA formation was inhibited under acid conditions (pH≤5) mainly due to the protonation of amines. Water matrix such as HCO 3 - and humic acid impacted NDMA generation due to OH scavenging. Compared with OH, ozone molecules dominated the productions of DMA and NDMA. However, OH was a critical factor in NDMA degradation. Transformation products of ranitidine during ozonation were identified using gas chromatography-mass spectrometry. Among these products, just DMA and N,N-dimethylformamide could contribute to NDMA formation due to the DMA group in the molecular structures. The NDMA formation pathway from ranitidine ozonation was also proposed. Copyright © 2017. Published by Elsevier B.V.

Changes in Air CO₂ Concentration Differentially Alter Transcript Levels of NtAQP1 and NtPIP2;1 Aquaporin Genes in Tobacco Leaves.

PubMed

Secchi, Francesca; Schubert, Andrea; Lovisolo, Claudio

2016-04-14

The aquaporin specific control on water versus carbon pathways in leaves is pivotal in controlling gas exchange and leaf hydraulics. We investigated whether Nicotiana tabacum aquaporin 1 (NtAQP1) and Nicotiana tabacum plasma membrane intrinsic protein 2;1 (NtPIP2;1) gene expression varies in tobacco leaves subjected to treatments with different CO₂ concentrations (ranging from 0 to 800 ppm), inducing changes in photosynthesis, stomatal regulation and water evaporation from the leaf. Changes in air CO₂ concentration ([CO₂]) affected net photosynthesis (Pn) and leaf substomatal [CO₂] (Ci). Pn was slightly negative at 0 ppm air CO₂; it was one-third that of ambient controls at 200 ppm, and not different from controls at 800 ppm. Leaves fed with 800 ppm [CO₂] showed one-third reduced stomatal conductance (gs) and transpiration (E), and their gs was in turn slightly lower than in 200 ppm- and in 0 ppm-treated leaves. The 800 ppm air [CO₂] strongly impaired both NtAQP1 and NtPIP2;1 gene expression, whereas 0 ppm air [CO₂], a concentration below any in vivo possible conditions and specifically chosen to maximize the gene expression alteration, increased only the NtAQP1 transcript level. We propose that NtAQP1 expression, an aquaporin devoted to CO₂ transport, positively responds to CO₂ scarcity in the air in the whole range 0-800 ppm. On the contrary, expression of NtPIP2;1, an aquaporin not devoted to CO₂ transport, is related to water balance in the leaf, and changes in parallel with gs. These observations fit in a model where upregulation of leaf aquaporins is activated at low Ci, while downregulation occurs when high Ci saturates photosynthesis and causes stomatal closure.

DRINKING WATER DISINFECTION BY-PRODUCTS: WHAT IS KNOWN

EPA Science Inventory

Chlorine, ozone, chlorine dioxide, and chloramine are currently the major disinfectants being used to disinfect drinking water. Although the alternative disinfectants (ozone, chlorine dioxide, and chloramine) are increasing in popularity in the United States, chlorine is still us...

Use of ozone in a water reuse system for salmonids

USGS Publications Warehouse

Williams, R.C.; Hughes, S.G.; Rumsey, G.L.

1982-01-01

A water reuse system is described in which ozone is used in addition to biological filters to remove toxic metabolic wastes from the water. The system functions at a higher rate of efficiency than has been reported for other reuse systems and supports excellent growth of rainbow trout (Salmo gairdneri).

Prevention of Cross-contamination Risk by Disinfection of Irreversible Hydrocolloid Impression Materials with Ozonated Water.

PubMed

Savabi, Omid; Nejatidanesh, Farahnaz; Bagheri, Kamran Poshang; Karimi, Leila; Savabi, Ghazal

2018-01-01

Disinfection of dental impression is mandatory for preventing the cross infection between dental staff and dental laboratory. Ozone as a disinfectant can be used in various ways in dentistry. The aim of this study was to evaluate the efficacy of ozonated water for disinfection of irreversible hydrocolloid impression materials and preventing cross-contamination. Thirty-two circular specimens (1 cm diameter and 2 mm thickness) of irreversible hydrocolloid impression material were made. Thirty specimens were contaminated with Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 51299), and Candida albicans (PTCC 5027). Except control samples ( n = 2), the other specimens were immersed in ozonated water for 5 and 10 min (5 sample each group). Trypsin was used for separating microorganisms. Diluted microbial solution was analyzed microbiologically for colony-forming units (CFUs). Two-way repeated measure ANOVA and Scheffe post hoc test were used for data analysis (α = 0.05). The number of CFUs after disinfection with ozonated water was decreased significantly (11.84%, 61.55%, and 20.27% after 5 min and 11.03%, 14.50%, and 16.99% after 10 min for P. aeruginosa , S. aureus , and C. albicans , respectively) ( P < 0.001). Increasing the time of disinfection resulted in significant reduction in a number of S. aureus only ( P < 0.001) although they did not vanish microorganisms completely. Immersion of irreversible hydrocolloid impression material in ozonated water for 10 min will not lead to complete disinfection but decreases the microorganisms to a level that can prevent infection transmission.

Membrane fouling by extracellular polymeric substances after ozone pre-treatment: Variation of nano-particles size.

PubMed

Yu, Wenzheng; Zhang, Dizhong; Graham, Nigel J D

2017-09-01

The application of ozone pre-treatment for ultrafiltration (UF) in drinking water treatment has been studied for more than 10 years, but its performance in mitigating or exacerbating membrane fouling has been inconclusive, and sometimes contradictory. To help explain this, our study considers the significance of the influent organic matter and its interaction with ozone on membrane fouling, using solutions of two representative types of extracellular polymeric substances (EPS), alginate and bovine serum albumin (BSA), and samples of surface water. The results show that at typical ozone doses there is no measurable mineralization of alginate and BSA, but substantial changes in their structure and an increase in the size of nano-particle aggregates (micro-flocculation). The impact of ozonation on membrane fouling, as indicated by the membrane flux, was markedly different for the two types of EPS and found to be related to the size of the nano-particle aggregates formed in comparison with the UF pore size. Thus, for BSA, ozonation created aggregate sizes similar to the UF pore size (100 k Dalton) which led to an increase in fouling. In contrast, ozonation of alginate created the nano-particle aggregates greater than the UF pore size, giving reduced membrane fouling/greater flux. For solutions containing a mixture of the two species of EPS the overall impact of ozonation on UF performance depends on the relative proportion of each, and the ozone dose, and the variable behaviour has been demonstrated by the surface water. These results provide new information about the role of nano-particle aggregate size in explaining the reported ambiguity over the benefits of applying ozone as pre-treatment for ultrafiltration. Copyright © 2017. Published by Elsevier Ltd.

Effective degradation of methylisothiazolone biocide using ozone: Kinetics, mechanisms, and decreases in toxicity.

PubMed

Li, Ang; Wu, Qian-Yuan; Tian, Gui-Peng; Hu, Hong-Ying

2016-12-01

Methylisothiazolone (MIT) is a common biocide that is widely used in water-desalination reverse-osmosis processes. The transformation of MIT during water treatment processes is poorly understood. The kinetics and mechanisms involved in the degradation of MIT during ozonation were investigated in this study. Ozonation was found to be a useful way of degrading MIT in water, and the degradation rate constant was 0.11 (±0.1) × 10 3  L/(mol·s). The degradation rate constant did not change when the pH was increased from 3 to 9. The pre-exponential factor A and the activation energy E a for the ozonation process were 7.564 × 10 13  L/(mol·s) and 66.74 kJ/mol, respectively. The decrease in the MIT concentration and the amount of ozone consumed were measured, and the stoichiometric factor α for the ozone consumption to MIT removal ratio was found to be 1.8. Several ozonation products were detected using time-of-flight mass spectrometry. Almost 32% of the organic sulfur in the MIT was oxidized to release sulfate ions, which caused a decrease in pH. Sulfur atoms were oxidized to sulfone species and then hydrolyzed to give sulfate during ozonation. Addition reactions involving carbon-carbon double bonds and the oxidation of α-carbon atoms also occurred. MIT was found to be lethal to Daphnia magna Straus (D. magna) with a median lethal concentration of 18.2 μmol/L. Even though the primary ozonation products of MIT still showed some toxicity to D. magna, ozone could minimize the toxic effect after a long reaction time. Copyright © 2016 Elsevier Ltd. All rights reserved.

Lower stratospheric observations from aircraft and satellite during the 2015/2016 El Nino

NASA Astrophysics Data System (ADS)

Rosenlof, K. H.; Avery, M. A.; Davis, S. M.; Gao, R. S.; Thornberry, T. D.

2016-12-01

Winter 2015/2016 experienced a strong El Nino that was heavily observed by aircraft, radiosonde and satellite platforms. During the National Oceanographic and Atmospheric Administration's (NOAA) Sensing Hazards with Operational Unmanned Technology (SHOUT)/El Nino Rapid Response (ENRR) flights of the NASA Global Hawk, in situ ozone measurements were made in the lower stratosphere over the Pacific. These will be contrasted with ozone measurements taken during La Nina and ENSO neutral conditions during past Global Hawk aircraft campaigns. Additionally, lower stratospheric water vapor and ozone measurements from the Microwave Limb Sounder satellite instrument and stratospheric ice measurements above the tropopause from the Cloud-Aerosol Aerosol Lidar with Orthogonal Polarization (CALIOP) will be presented. Our aircraft ozone measurements are higher for the El Nino flights than during other missions previously sampled, while zonally averaged lower stratospheric water vapor and central Pacific ice path above the tropopause reached record highs. Implications and possible reasons for these anomalous observations will be discussed. Winter 2015/2016 experienced a strong El Nino that was heavily observed by aircraft, radiosonde and satellite platforms. During the National Oceanographic and Atmospheric Administration's (NOAA) Sensing Hazards with Operational Unmanned Technology (SHOUT)/El Nino Rapid Response (ENRR) flights of the NASA Global Hawk, in situ ozone measurements were made in the upper troposphere and lower stratosphere (UTLS) over the Pacific. These will be contrasted with ozone measurements made during La Nina and ENSO neutral conditions during past Global Hawk aircraft campaigns. Additionally, UTLS water vapor and ozone measurements from the Microwave Limb Sounder (MLS) satellite instrument and stratospheric ice measurements above the tropopause from the Cloud-Aerosol Aerosol Lidar with Orthogonal Polarization (CALIOP) will be presented. Our aircraft ozone measurements are higher in the upper troposphere for the El Nino flights than during other missions previously sampled, while zonally averaged lower stratospheric water vapor and ice water paths above the tropopause over the central Pacific reached record highs. Implications and possible reasons for these anomalous observations will be discussed.

MBR/RO/ozone processes for TFT-LCD industrial wastewater treatment and recycling.

PubMed

Chen, T K; Ni, C H; Chan, Y C; Lu, M C

2005-01-01

This research is mainly to explore the treatment capacity for TFT-LCD industrial wastewater recycling by the processes combined with membrane bioreactor (MBR), reverse osmosis (RO) and ozone(O3). The organic wastewater from the TFT-LCD industry was selected as the target. MBR, RO and ozone plants were established for evaluation. An MBR plant consisted of a 2-stage anoxic/aerobic bioreactor and an immersed UF membrane unit was employed. The effluent of MBR was conducted into the RO system then into the ozone system. The RO system consisted of a spiral membrane in the vessel. One bubble column, 75 cm high and diameter 5 cm, were used as the ozonation reactor. On the bottom of ozonation reactor is a porous diffuser for releasing gas, with an aperture of 100 microm (0.1 cm). Over the whole experimental period, the MBR process achieved a satisfactory organic removal. The COD could be removed with an average of over 98.5%. For the TOC item, the average removal efficiency was 97.4%. The stable effluent quality and satisfactory removal performance were ensured by the efficient interception performance of an immersed UF membrane device incorporated with the biological reactor. Moreover, the MBR effluent did not contain any suspended solids and the SDI value was under 3. After the treatment of RO, excellent water quality was found. The water quality of permeate was under 5 mg/I, 2 mg/l and 50 micros/cm for COD, TOC and conductivity respectively. The treated water can be recycled and reused for the cooling tower make-up water or other purposes. After the treatment of ozone, the treated water quality was under 5 mg/l and 0.852 mg/l for COD and TOC respectively. The test results of MBR, MBR/RO and MBR/RO/ozone processes were compared as possible appropriate treatment technologies applied in TFT-LCD industrial wastewater reuse and recycling.

The impacts of ozonation on oil sands process-affected water biodegradability and biofilm formation characteristics in bioreactors.

PubMed

Hwang, Geelsu; Dong, Tao; Islam, Md Sahinoor; Sheng, Zhiya; Pérez-Estrada, Leónidas A; Liu, Yang; Gamal El-Din, Mohamed

2013-02-01

To examine the effects of the ozonation process (as an oxidation treatment for water and wastewater treatment applications) on microbial biofilm formation and biodegradability of organic compounds present in oil sands process-affected water (OSPW), biofilm reactors were operated continuously for 6weeks. Two types of biofilm substrate materials: polyethylene (PE) and polyvinylchloride (PVC), and two types of OSPW-fresh and ozonated OSPWs-were tested. Endogenous microorganisms, in OSPW, quickly formed biofilms in the reactors. Without ozonation, the bioreactor (using endogenous microorganisms) removed 13.8% of the total acid-extractable organics (TAO) and 18.5% of the parent naphthenic acids (NAs) from fresh OSPW. The combined ozonation and biodegradation process removed 87.2% of the OSPW TAO and over 99% of the OSPW parent NAs. Further UPLC/HRMS analysis showed that NA biodegradability decreased as the NA cyclization number increased. Microbial biofilm formation was found to depend on the biofilm substrate type. Copyright © 2012 Elsevier Ltd. All rights reserved.

Combination of ozone and packaging treatments maintained the quality and improved the shelf life of tomato fruit

NASA Astrophysics Data System (ADS)

Zainuri; Jayaputra; Sauqi, A.; Sjah, T.; Desiana, R. Y.

2018-01-01

Tomato is very important vegetable crop but has short shelf life. The objective of this research was to determine the effect of ozone and packaging combination treatment on the quality and the storage life of tomato fruit. There were six treatments including: control (without ozone and packaging); without ozone and packaged with polyethylene bag; without ozone and polyethylene terephtalate punnet; with ozone but without packaging; with ozone and packaged with polyethylene bag; and with ozone and polyethylene terephtalate punnet. Each treatment was made into 3 replications. Tomato samples were harvested at turning stage. Ozone treatment was applied for 60 seconds. Tomatoes were then treated with and without packaging. The fruit were then stored at room temperature for up to 12 days. The parameters for assessment were water content, color, texture, weight loss and the population of naturally contamination Escherichia coli. Each parameter was assessed on day 0, 6 and 12 of storage. The results indicated that combination of ozone and packaging treatments significantly affected the physical and biochemical changes (water content, color, texture and weight loss) of the fruit, suppressed the microbiological contamination on the fruit and maintained fruit freshness or quality after 12 days of storage. The combination of ozone and perforated polyethylene packaging treatment was the best treatment to maintain the quality and prolonged the shelf life of tomato fruit to be 12 days at room temperature.

On the Climate Impacts of Upper Tropospheric and Lower Stratospheric Ozone

NASA Astrophysics Data System (ADS)

Xia, Yan; Huang, Yi; Hu, Yongyun

2018-01-01

The global warming simulations of the general circulation models (GCMs) are generally performed with different ozone prescriptions. We find that the differences in ozone distribution, especially in the upper tropospheric and lower stratospheric (UTLS) region, account for important model discrepancies shown in the ozone-only historical experiment of the Coupled Model Intercomparison Project Phase 5 (CMIP5). These discrepancies include global high cloud fraction, stratospheric temperature, and stratospheric water vapor. Through a set of experiments conducted by an atmospheric GCM with contrasting UTLS ozone prescriptions, we verify that UTLS ozone not only directly radiatively heats the UTLS region and cools the upper parts of the stratosphere but also strongly influences the high clouds due to its impact on relative humidity and static stability in the UTLS region and the stratospheric water vapor due to its impact on the tropical tropopause temperature. These consequences strongly affect the global mean effective radiative forcing of ozone, as noted in previous studies. Our findings suggest that special attention should be paid to the UTLS ozone when evaluating the climate effects of ozone depletion in the 20th century and recovery in the 21st century. UTLS ozone difference may also be important for understanding the intermodel discrepancy in the climate projections of the CMIP6 GCMs in which either prescribed or interactive ozone is used.

Influence of conjunctive use of coffee effluent and fresh water on performance of robusta coffee and soil properties.

PubMed

Salakinkop, S R; Shivaprasad, P

2012-01-01

A field experiment was conducted to study the influence of treated coffee effluent irrigation on performance of established robusta coffee, nutrient contribution and microbial activities in the soil. The results revealed that the field irrigated with coffee effluent from aerobic tank having COD of 1009 ppm, did not affect the yield of clean coffee (1309 kg/ha) and it was statistically similar (on par) with the plots irrigated with fresh water (1310 kg/ha) with respect to clean coffee yield. Effluent irrigation increased significantly the population bacteria, yeast, fungi, actinomycetes and PSB (122, 52, 12, 34 and 6 x 104/g respectively)) in the soil compared to the soil irrigated with fresh water (87, 22, 5, 24 and 2 x 10(4)/g respectively). The organic carbon (2.60%), available nutrients in the soil like P (57.2 kg/ha), K (401.6 kg/ha, Ca (695.3 ppm), S (5.3 ppm),Cu (4.09 ppm) and Zn(4.78 ppm) were also increased due to effluent irrigation compared to fresh water irrigation. Thus analysis of coffee effluent for major and minor plant nutrients content revealed its potential as source of nutrients and water for plant growth.

46 CFR 162.050-27 - Oil content meter: Approval tests.

Code of Federal Regulations, 2011 CFR

2011-10-01

... with water for 15 minutes and then with mixtures in the following concentrations: 15 ppm, 50 ppm, 100 ppm, and each additional concentration, in increments of 50 ppm up to the highest oil concentration that can be read on the meter. Each mixture is fed to the meter in the order listed in Table 162.050-27...

Effect of Ozone on Intestinal Epithelial Homeostasis in a Rat Model

PubMed Central

Sukhotnik, Igor; Starikov, Alona; Coran, Arnold G.; Pollak, Yulia; Sohotnik, Rima; Shaoul, Ron

2015-01-01

Background: The positive effects of ozone therapy have been described in many gastrointestinal disorders. The mechanisms of this positive effect of ozone therapy are poorly understood. The purpose of the present study was to investigate whether the use of ozone may potentiate the gut intestinal mucosal homeostasis in a rat model. Methods: Adult rats weighing 250–280 g were randomly assigned to one of three experimental groups of 8 rats each: 1) Control rats were given 2 mL of water by gavage and intraperitoneally (IP) for 5 days; 2) O3-PO rats were treated with 2 mL of ozone/oxygen mixture by gavage and 2 mL of water IP for 5 days; 3) O3-IP rats were treated with 2 mL of water by gavage and 2 mL of ozone/oxygen mixture IP for 5 days. Rats were sacrificed on day 6. Bowel and mucosal weight, mucosal DNA and protein, villus height and crypt depth, and cell proliferation and apoptosis were evaluated following sacrifice. Results: The group of O3-IP rats demonstrated a greater jejunal and ileal villus height and crypt depth, a greater enterocyte proliferation index in jejunum, and lower enterocyte apoptosis in ileum compared to control animals. Oral administration of the ozone/oxygen mixture resulted in a less significant effect on cell turnover. Conclusions: Treatment with an ozone/oxygen mixture stimulates intestinal cell turnover in a rat model. Intraperitoneal administration of ozone resulted in a more significant intestinal trophic effect than oral administration. PMID:25717388

Naphthenic acids speciation and removal during petroleum-coke adsorption and ozonation of oil sands process-affected water.

PubMed

Gamal El-Din, Mohamed; Fu, Hongjing; Wang, Nan; Chelme-Ayala, Pamela; Pérez-Estrada, Leonidas; Drzewicz, Przemysław; Martin, Jonathan W; Zubot, Warren; Smith, Daniel W

2011-11-01

The Athabasca Oil Sands industry produces large volumes of oil sands process-affected water (OSPW) as a result of bitumen extraction and upgrading processes. Constituents of OSPW include chloride, naphthenic acids (NAs), aromatic hydrocarbons, and trace heavy metals, among other inorganic and organic compounds. To address the environmental issues associated with the recycling and/or safe return of OSPW into the environment, water treatment technologies are required. This study examined, for the first time, the impacts of pretreatment steps, including filtration and petroleum-coke adsorption, on ozonation requirements and performance. The effect of the initial OSPW pH on treatment performance, and the evolution of ozonation and its impact on OSPW toxicity and biodegradability were also examined. The degradation of more than 76% of total acid-extractable organics was achieved using a semi-batch ozonation system at a utilized ozone dose of 150 mg/L. With a utilized ozone dose of 100 mg/L, the treated OSPW became more biodegradable and showed no toxicity towards Vibrio fischeri. Changes in the NA profiles in terms of carbon number and number of rings were observed after ozonation. The filtration of the OSPW did not improve the ozonation performance. Petroleum-coke adsorption was found to be effective in reducing total acid-extractable organics by a 91%, NA content by an 84%, and OSPW toxicity from 4.3 to 1.1 toxicity units. The results of this study indicate that the combination of petroleum-coke adsorption and ozonation is a promising treatment approach to treat OSPW. Copyright © 2011 Elsevier B.V. All rights reserved.

A smog chamber study coupling a photoionization aerosol electron/ion spectrometer to VUV synchrotron radiation: organic and inorganic-organic mixed aerosol analysis

NASA Astrophysics Data System (ADS)

Baeza-Romero, María Teresa; Gaie-Levrel, Francois; Mahjoub, Ahmed; López-Arza, Vicente; Garcia, Gustavo A.; Nahon, Laurent

2016-07-01

A reaction chamber was coupled to a photoionization aerosol time-of-flight mass spectrometer based on an electron/ion coincidence scheme and applied for on-line analysis of organic and inorganic-organic mixed aerosols using synchrotron tunable vacuum ultraviolet (VUV) photons as the ionization source. In this proof of principle study, both aerosol and gas phase were detected simultaneously but could be differentiated. Present results and perspectives for improvement for this set-up are shown in the study of ozonolysis ([O3] = 0.13-3 ppm) of α-pinene (2-3 ppm), and the uptake of glyoxal upon ammonium sulphate. In this work the ozone concentration was monitored in real time, together with the particle size distributions and chemical composition, the latter taking advantage of the coincidence spectrometer and the tuneability of the synchrotron radiation as a soft VUV ionization source.

Activation of calcitonin gene-related peptide receptor during ozone inhalation contributes to airway epithelial injury and repair.

PubMed

Oslund, Karen L; Hyde, Dallas M; Putney, Leialoha F; Alfaro, Mario F; Walby, William F; Tyler, Nancy K; Schelegle, Edward S

2009-10-01

The authors investigated the importance of the neuropeptide, calcitonin gene-related peptide (CGRP), in epithelial injury, repair, and neutrophil emigration after ozone exposure. Wistar rats were administered either a CGRP-receptor antagonist (CGRP(8-37)) or saline and exposed to 8 hours of 1-ppm ozone or filtered air with an 8-hour postexposure period. Immediately after exposure, ethidium homodimer was instilled into lungs as a marker of necrotic airway epithelial cells. After fixation, airway dissected lung lobes were stained for 5'-bromo-2'-deoxyuridine, a marker of epithelial proliferation. Positive epithelial cells were quantified in specific airway generations. Rats treated with CGRP(8-37) had significantly reduced epithelial injury in terminal bronchioles and reduced epithelial proliferation in proximal airways and terminal bronchioles. Bronchoalveolar lavage and sections of terminal bronchioles showed no significant difference in the number of neutrophils emigrating into airways in CGRP(8-37)-treated rats. The airway epithelial cell line, HBE-1, showed no difference in the number of oxidant stress positive cells during exposure to hydrogen peroxide and a range of CGRP(8-37) doses, demonstrating no antioxidant effect of CGRP(8-37). We conclude that activation of CGRP receptors during ozone inhalation contributes to airway epithelial injury and subsequent epithelial proliferation, a critical component of repair, but does not influence neutrophil emigration into airways.

Repeated episodes of ozone inhalation attenuates airway injury/repair and release of substance P, but not adaptation.

PubMed

Schelegle, Edward S; Walby, William F; Alfaro, Mario F; Wong, Viviana J; Putney, Lei; Stovall, Mary Y; Sterner-Kock, Anja; Hyde, Dallas M; Plopper, Charles G

2003-02-01

To determine the impact of repeated episodes of ozone exposure on physiologic adaptation, epithelial injury/repair, and tracheal substance P levels, adult rats were subjected to episodes of ozone (5 days, 1 ppm, 8 h/day) followed by 9 days of filtered air for four cycles. Rats were sampled on days 1 and 5 of each episode and 9 days after day 5 of episodes 1, 2, and 4. One hour before being euthanized each rat was injected with 5-bromo-2'-deoxyuridine to label proliferating cells. Each 5-day episode showed a characteristic pattern of rapid shallow breathing (days 1 and 2), epithelial injury, and interstitial and intraluminal inflammation. In contrast, the neutrophil component of inflammation, tracheal substance P release, and cell proliferation became attenuated with each consecutive episode of exposure. Concurrent with this cyclic and attenuated response there was progressive hypercellularity and hyperplasia in all airways studied and a progressive remodeling present in the terminal bronchioles. Our findings are consistent with the notion that the cumulative distal airway lesion is at least in part the result of a depressed cell proliferative response to injury in these airways. This depressed cell proliferative response may be in part the result of diminished neutrophil inflammation and/or release of mitogenic neuropeptides in response to ozone-induced injury.

Technical note: Examining ozone deposition over seawater

EPA Science Inventory

Surface layer resistance plays an important role in determining ozone deposition velocity over sea-water and can be influenced by chemical interactions at the air-water interface. Here, we examine the effect of chemical interactions of iodide, dimethylsulfide, dissolved organic c...

Chemical effect on ozone deposition over seawater

EPA Science Inventory

Surface layer resistance plays an important role in determining ozone deposition velocity over seawater. Recent studies suggest that surface layer resistance over sea-water is influenced by wind-speed and chemical interaction at the air-water interface. Here, we investigate the e...

Sequential disinfection of E. coli O157:H7 on shredded lettuce leaves by aqueous chlorine dioxide, ozonated water, and thyme essential oil

NASA Astrophysics Data System (ADS)

Singh, Nepal; Singh, Rakesh K.; Bhunia, Arun K.; Stroshine, Richard L.; Simon, James E.

2001-03-01

There have been numerous studies on effectiveness of different sanitizers for microbial inactivation. However, results obtained from different studies indicate that microorganism cannot be easily removed from fresh cut vegetables because of puncture and cut surfaces with varying surface topographies. In this study, three step disinfection approach was evaluated for inactivation of E. coli O157:H7 on shredded lettuce leaves. Sequential application of thyme oil, ozonated water, and aqueous chlorine dioxide was evaluated in which thyme oil was applied first followed by ozonated water and aqueous chlorine dioxide. Shredded lettuce leaves inoculated with cocktail culture of E. coli O157:H7 (C7927, EDL 933 and 204 P), were washed with ozonated water (15 mg/l for 10min), aqueous chlorine dioxide (10 mg/l,for 10min) and thyme oil suspension (0.1%, v/v for 5min). Washing of lettuce leaves with ozonated water, chlorine dioxide and thyme oil suspension resulted in 0.44, 1.20, and 1.46 log reduction (log10 cfu/g), respectively. However, the sequential treatment achieved approximately 3.13 log reductions (log10 cfu/g). These results demonstrate the efficacy of sequential treatments in decontaminating shredded lettuce leaves containing E. coli O157:H7.

Seasonal/Diurnal Mapping of Ozone and Water in the Martian Atmosphere

NASA Technical Reports Server (NTRS)

Novak, R. E.; Mumma, M. J.; DiSanti, M. A.; DelloRusso, N.; Magee-Sauer, K.; Bonev, B.

2003-01-01

Ozone and water are key species for understanding the stability and evolution of Mars atmosphere; they are closely linked (along with CO, H, OH, and O) through photochemistry. Photolysis of water produces the OH radical (thought to catalyze reformation of CO2 from CO and O2) and atomic hydrogen (which reacts with O3 forming OH and O2). Atomic hydrogen also reacts with O2 (forming HO2), thereby reducing the amount of O2 available to reform O3 from collisions between O and O2. Hence ozone and water should be anti-correlated on Mars. Photolysis of O3 produces O2(a(sup 1) delta g) with 90% efficiency, and the resulting emission band system near 1.27 mm traces the presence and abundance of ozone. This approach was initially used to study ozone on Earth and then applied to Mars. In 1997, we measured several lines of the O2(a(sup 1) delta g) emission using CSHELL at the NASA IRTF; the O2(a(sup 1) delta g) state is also quenched by collisions with CO2. This quenching dominates at lower altitudes so that the detected emissions are used to detect ozone column densities above 20 km. The slit was positioned N-S along Mars' central meridian resulting in a one-dimensional map of ozone. Nearly simultaneous maps may be made of water using CSHELL by detecting the v1 fundamental band of HDO near 3.67 microns and using the D/H ratio for Mars. This technique was used by DiSanti and Mumma. With CSHELL, measurements for both O2(a(sup 1) delta g) emissions and HDO absorptions can be made during the day or night. Since January, 1997, we have repeated these measurements at different times during the Martian year. For all of these dates, we have positioned the slit N-S along the central meridian; for some of these dates, we have also stepped the slit across the planet at 1 arc-sec intervals generating a 2-dimensional map. We have also positioned the slit E-W on Mars thus providing diurnal variations of ozone and water along the slit.

Recovery of Fresh Water Resources from Desalination of Brine Produced During Oil and Gas Production Operations

DOE Office of Scientific and Technical Information (OSTI.GOV)

David B. Burnett; Mustafa Siddiqui

2006-12-29

Management and disposal of produced water is one of the most important problems associated with oil and gas (O&G) production. O&G production operations generate large volumes of brine water along with the petroleum resource. Currently, produced water is treated as a waste and is not available for any beneficial purposes for the communities where oil and gas is produced. Produced water contains different contaminants that must be removed before it can be used for any beneficial surface applications. Arid areas like west Texas produce large amount of oil, but, at the same time, have a shortage of potable water. Amore » multidisciplinary team headed by researchers from Texas A&M University has spent more than six years is developing advanced membrane filtration processes for treating oil field produced brines The government-industry cooperative joint venture has been managed by the Global Petroleum Research Institute (GPRI). The goal of the project has been to demonstrate that treatment of oil field waste water for re-use will reduce water handling costs by 50% or greater. Our work has included (1) integrating advanced materials into existing prototype units and (2) operating short and long-term field testing with full size process trains. Testing at A&M has allowed us to upgrade our existing units with improved pre-treatment oil removal techniques and new oil tolerant RO membranes. We have also been able to perform extended testing in 'field laboratories' to gather much needed extended run time data on filter salt rejection efficiency and plugging characteristics of the process train. The Program Report describes work to evaluate the technical and economical feasibility of treating produced water with a combination of different separation processes to obtain water of agricultural water quality standards. Experiments were done for the pretreatment of produced water using a new liquid-liquid centrifuge, organoclay and microfiltration and ultrafiltration membranes for the removal of hydrocarbons from produced water. The results of these experiments show that hydrocarbons from produced water can be reduced from 200 ppm to below 29 ppm level. Experiments were also done to remove the dissolved solids (salts) from the pretreated produced water using desalination membranes. Produced water with up to 45,000 ppm total dissolved solids (TDS) can be treated to agricultural water quality water standards having less than 500 ppm TDS. The Report also discusses the results of field testing of various process trains to measure performance of the desalination process. Economic analysis based on field testing, including capital and operational costs, was done to predict the water treatment costs. Cost of treating produced water containing 15,000 ppm total dissolved solids and 200 ppm hydrocarbons to obtain agricultural water quality with less than 200 ppm TDS and 2 ppm hydrocarbons range between $0.5-1.5 /bbl. The contribution of fresh water resource from produced water will contribute enormously to the sustainable development of the communities where oil and gas is produced and fresh water is a scarce resource. This water can be used for many beneficial purposes such as agriculture, horticulture, rangeland and ecological restorations, and other environmental and industrial application.« less

Water contents of clinopyroxenes from sub-arc mantle peridotites

USGS Publications Warehouse

Turner, Michael; Turner, Simon; Blatter, Dawnika; Maury, Rene; Perfit, Michael; Yogodzinski, Gene

2017-01-01

One poorly constrained reservoir of the Earth's water budget is that of clinopyroxene in metasomatised, mantle peridotites. This study presents reconnaissance Sensitive High-Resolution, Ion Microprobe–Stable Isotope (SHRIMP–SI) determinations of the H2O contents of (dominantly) clinopyroxenes in rare mantle xenoliths from four different subduction zones, i.e. Mexico, Kamchatka, Philippines, and New Britain (Tabar-Feni island chain) as well as one intra-plate setting (western Victoria). All of the sub-arc xenoliths have been metasomatised and carry strong arc trace element signatures. Average measured H2O contents of the pyroxenes range from 70 ppm to 510 ppm whereas calculated bulk H2O contents range from 88 ppm to 3 737 ppm if the variable presence of amphibole is taken into account. In contrast, the intra-plate, continental mantle xenolith from western Victoria has higher water contents (3 447 ppm) but was metasomatised by alkali and/or carbonatitic melts and does not carry a subduction-related signature. Material similar to the sub-arc peridotites can either be accreted to the base of the lithosphere or potentially be transported by convection deeper into the mantle where it will lose water due to amphibole breakdown.

Selective oxidation of key functional groups in cyanotoxins during drinking water ozonation.

PubMed

Onstad, Gretchen D; Strauch, Sabine; Meriluoto, Jussi; Codd, Geoffrey A; Von Gunten, Urs

2007-06-15

Chemical kinetics were determined for the reactions of ozone and hydroxyl radicals with the three cyanotoxins microcystin-LR (MC-LR), cylindrospermopsin (CYN) and anatoxin-a (ANTX). The second-order rate constants (k(O3)) at pH 8 were 4.1 +/- 0.1 x 10(5) M(-1) s(-1) for MC-LR, approximately 3.4 x 10(5) M(-1) s(-1) for CYN, and approximately 6.4 x 10(4) M(-1) s(-1) for ANTX. The reaction of ozone with MC-LR exhibits a k(O3) similar to that of the conjugated diene in sorbic acid (9.6 +/- 0.3 x 10(5) M(-1) s(-1)) at pH 8. The pH dependence and value of k(O3) for CYN at pH > 8 (approximately 2.5 +/- 0.1 x 10(6) M(-1) s(-1)) are similar to deprotonated amines of 6-methyluracil. The k(O3) of ANTX at pH > 9 (approximately 8.7 +/- 2.2 x 10(5) M(-1) s(-1)) agrees with that of neutral diethylamine, and the value at pH < 8 (2.8 +/- 0.2 x 10(4) M(-1) s(-1)) corresponds to an olefin. Second-order rate constants for reaction with OH radicals (*OH), k(OH) for cyanotoxins were measured at pH 7 to be 1.1 +/- 0.01 x 10(10) M(-1) s(-1) for MC-LR, 5.5 +/- 0.01 x 10(9) M(-1) s(-1) for CYN, and 3.0 +/- 0.02 x 10(9) M(-1) s(-1) for ANTX. Natural waters from Switzerland and Finland were examined for the influence of variations of dissolved organic matter, SUVA254, and alkalinity on cyanotoxin oxidation. For a Swiss water (1.6 mg/L DOC), 0.2, 0.4, and 0.8 mg/L ozone doses were required for 95% oxidation of MC-LR, CYN, and ANTX, respectively. For the Finnish water (13.1 mg/L DOC), >2 mg/L ozone dose was required for each toxin. The contribution of hydroxyl radicals to toxin oxidation during ozonation of natural water was greatest for ANTX > CYN > MC-LR. Overall, the order of reactivity of cyanotoxins during ozonation of natural waters corresponds to the relative magnitudes of the second-order rate constants for their reaction with ozone and *OH. Ozone primarily attacks the structural moieties responsible for the toxic effects of MC-LR, CYN, and ANTX, suggesting that ozone selectively detoxifies these cyanotoxins.

Process analysis and economics of drinking water production from coastal aquifers containing chromophoric dissolved organic matter and bromide using nanofiltration and ozonation.

PubMed

Sobhani, R; McVicker, R; Spangenberg, C; Rosso, D

2012-01-01

In regions characterized by water scarcity, such as coastal Southern California, groundwater containing chromophoric dissolved organic matter is a viable source of water supply. In the coastal aquifer of Orange County in California, seawater intrusion driven by coastal groundwater pumping increased the concentration of bromide in extracted groundwater from 0.4 mg l⁻¹ in 2000 to over 0.8 mg l⁻¹ in 2004. Bromide, a precursor to bromate formation is regulated by USEPA and the California Department of Health as a potential carcinogen and therefore must be reduced to a level below 10 μg l⁻¹. This paper compares two processes for treatment of highly coloured groundwater: nanofiltration and ozone injection coupled with biologically activated carbon. The requirement for bromate removal decreased the water production in the ozonation process to compensate for increased maintenance requirements, and required the adoption of catalytic carbon with associated increase in capital and operating costs per unit volume. However, due to the absence of oxidant addition in nanofiltration processes, this process is not affected by bromide. We performed a process analysis and a comparative economic analysis of capital and operating costs for both technologies. Our results show that for the case studied in coastal Southern California, nanofiltration has higher throughput and lower specific capital and operating cost, when compared to ozone injection with biologically activate carbon. Ozone injection with biologically activated carbon, compared to nanofiltration, has 14% higher capital cost and 12% higher operating costs per unit water produced while operating at the initial throughput. Due to reduced ozone concentration required to accommodate for bromate reduction, the ozonation process throughput is reduced and the actual cost increase (per unit water produced) is 68% higher for capital cost and 30% higher for operations. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of ozone and granular activated coal (GAC) on the bioactivity of drinking water.

PubMed

Sallanko, Jarmo; Iivari, Pekka; Heiska, Eeva

2009-02-15

In this research, the appearance of easily biodegradable organic material in ozonation and granular activated coal (GAC) filtration was studied. The amount of bioactivity was measured by conventional AOC analyses used in two different modes and also using quite a new growth potential (GP) method. GAC filtration without ozone doubled the amount of AOC of the chemically treated surface water, whereas by ozonation with GAC filtration it was possible to halve the amount of the AOC. The measurement of GP was noticeably simpler than measuring AOC, but for wider use more parallel studies are needed for the comparability of the results of the analysis.

Application of ozone for the removal of bisphenol A from water and wastewater--a review.

PubMed

Umar, Muhammad; Roddick, Felicity; Fan, Linhua; Aziz, Hamidi Abdul

2013-02-01

The extensive use of Bisphenol A (BPA) in the plastics industry has led to increasing reports of its presence in the aquatic environment, with concentrations of ng L(-1) to μg L(-1). Various advanced oxidation processes, including ozonation, have been shown to effectively degrade BPA. This paper reviews the current advancements in using ozone to remove BPA from water and wastewater. Most of the published work on the oxidation of BPA by ozone has focused on the efficiency of BPA removal in terms of the disappearance of BPA, and the effect of various operational parameters such as ozone feed rate, contact time and pH; some information is available on the estrogenic activity of the treated water. Due to increasing operational reliability and cost effectiveness, there is great potential for industrial scale application of ozone for the treatment of BPA. However, there is a significant lack of information on the formation of oxidation by-products and their toxicities, particularly in more complex matrices such as wastewater, and further investigation is needed for a better understanding of the environmental fate of BPA. Copyright © 2012 Elsevier Ltd. All rights reserved.

The vertical structure of ozone and water vapor profiles in Lhasa within Asia summer monsoon anticyclone during the stratospheric intrusion

NASA Astrophysics Data System (ADS)

Li, Dan; Vogel, Bärbel; Bian, Jianchun; Müller, Rolf; Günther, Gebhard; Bai, Zhixuan; Li, Qian; Fan, Qiujun; Zhang, Jinqiang

2017-04-01

A stratospheric intrusion process occurred over the southeastern side of the Asia summer monsoon (ASM) region is investigated using the balloon-borne measurements of ozone and water vapor during 18-20 August 2013. Data from Lhasa (29.66° N, 91.14° E, above sea level (asl.) 3,650 m) show that the positive relative change of the ozone mixing ratios in the tropopause layer attained to 90 % on 19 and 20 August. The backward trajectory calculation from CLaMS model and the satellite data from the ozone monitoring instrument (OMI) and the atmospheric infrared sounder (AIRS) indicate that the (stratospheric) air parcels intruded (originated) from the Northeast Asia to the southeastern edge of the ASM anticyclone. Meanwhile, typhoon Utor occurred over the sourtheastern edge of the ASM and lasted from 8 to 18 August 2013. The convection associated with Utor uplifted air with low ozone from the Western Pacific to the middle/upper troposphere. Air parcels with high ozone from the high latitude and with low ozone from the Western Pacific met at the sourtheastern side of the ASM and then transported westward to Lhasa over long-distances (˜2,000 km). In addition, the laminated identification method is used to identify the laminae structure of the ozone and water vapor profiles from the middle troposphere to the lower stratosphere in Lhasa, confirming the role of the dynamic disturbance (e.g., Rossby and gravity wave)

Kinetics of ozone-initiated oxidation of textile dye, Amaranth in aqueous systems.

PubMed

Dachipally, Purnachandar; Jonnalagadda, Sreekanth B

2011-01-01

The ozone facilitated oxidation mechanism of water soluble azo anionic dye, amaranth (Am) was investigated monitoring the depletion kinetics of the dye spectrometrically at 521 nm. The oxidation kinetics of the dye by ozone was studied under semi-batch conditions, by bubbling ozone enriched oxygen through the aqueous reaction mixture of dye, as function of flow rate, ionic strength, [O(3)] and pH variations. With excess concentration of ozone and other reagents and low [amaranth], reaction followed pseudo-first-order kinetics with respect to the dye. Added neutral salts had marginal effect on the reaction rate and the variation of pH from 7 to 2 and 7 to 12 exerted only small increases in the reaction rate suggesting molecular ozone possibly is the principle reactive species in oxidation of dye. The reaction order with respect ozone was near unity and it varied slightly with pH and flow rate variations. The overall second-order rate constant for the reaction was (105 ± 4) M(-1) min(-1). The main oxidation products immediately after amaranth decolorization were identified. The reaction mechanism and overall rate law were proposed. After spiking the seawater, river water and wastewaters with Amaranth dye, the reaction rates and trends in BOD and COD under control and natural conditions were investigated. The rate of depletion of the dye in natural waters was relatively lower, but the ozonation process significantly decreased both the BOD and COD levels.

Accumulation of Pb and Cu heavy metals in sea water, sediment, and leaf and root tissue of Enhalus sp. in the seagrass bed of Banten Bay

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fauziah, Faiza, E-mail: faiza.fauziah@gmail.com; Choesin, Devi N., E-mail: faiza.fauziah@gmail.com

2014-03-24

Banten Bay in Indonesia is a coastal area which has been highly affected by human activity. Previous studies have reported the presence of lead (Pb) and copper (Cu) heavy metals in the seawater of this area. This study was conducted to measure the accumulation of Pb and Cu in seawater, sediment, leaf tissue, and root tissue of the seagrass species Enhalus sp. Sampling was conducted at two observation stations in Banten Bay: Station 1 (St.1) was located closer to the coastline and to industrial plants as source of pollution, while Station 2 (St.2) was located farther away offshore. At eachmore » station, three sampling points were established by random sampling. Field sampling was conducted at two different dates, i.e., on 29 May 2012 and 30 June 2012. Samples were processed by wet ashing using concentrated HNO{sub 3} acid and measured using Atomic Absorption Spectrometry (AAS). Accumulation of Pb was only detected in sediment samples in St.1, while Cu was detected in all samples. Average concentrations of Cu in May were as follows: sediment St.1 = 0.731 ppm, sediment St.2 = 0.383 ppm, seawater St.1 = 0.163 ppm, seawater St.2 = 0.174 ppm, leaf St.1 = 0.102 ppm, leaf St.2 = 0.132 ppm, root St.1= 0.139 ppm, and root St.2 = 0.075 ppm. Average measurements of Cu in June were: sediment St.1 = 0.260 ppm, leaf St.1 = 0.335 ppm, leaf St.2 = 0.301 ppm, root St.1= 0.047 ppm, and root St.2 = 0.060 ppm. In June, Cu was undetected in St.2 sediment and seawater at both stations. In May, Cu concentration in seawater exceeded the maximum allowable threshold for water as determined by the Ministry of the Environment. Spatial and temporal variation in Pb and Cu accumulation were most probably affected by distance from source and physical conditions of the environment (e.g., water current and mixing)« less

Evaluation of empirical process design relationships for ozone disinfection of water and wastewater

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finch, G.R.; Smith, D.W.

A research program was undertaken to examine the dose-response of Escherichia coli ATCC 11775 in ozone demand-free phosphate buffer solution and in a high quality secondary wastewater effluent with a total organic carbon content of 8 mg/L and a chemical oxygen demand of 26 mg/L. The studies were conducted in bench-scale batch reactors for both water types. In addition, studies using secondary effluent also were conducted in a pilot-scale, semi-batch reactor to evaluate scale-up effects. It was found that the ozone dose was the most important design parameter in both types of water. Contact time was of some importance inmore » the ozone demand-free water and had no detectable effect in the secondary effluent. Pilot-scale data confirmed the results obtained at bench-scale for the secondary effluent. Regression analysis of the logarithm of the E. coli response on the logarithm of the utilized ozone dose revealed that there was lack-of-fit using the model form which has been used frequently for the design of wastewater disinfection systems. This occurred as a result of a marked tailing effect of the log-log plot as the ozone dose increased and the kill increased. It was postulated that this was caused by some unknown physiological differences within the E. coli population due to age or another factor.« less

Reductions in bacterial microorganisms by filtration and ozonation of the surface water supply at the USFWS Northeast Fishery Center

USDA-ARS?s Scientific Manuscript database

A water filtration and ozonation system was recently installed to treat creek water used to culture species of concern at the U.S. Fish and Wildlife Service's Northeast Fishery Center, Lamar National Fish Hatchery (NFH). Past experience with fish culture indicates that the following bacterial pathog...