Montagna, Maria Teresa; De Giglio, Osvalda; Cristina, Maria Luisa; Napoli, Christian; Pacifico, Claudia; Agodi, Antonella; Baldovin, Tatjana; Casini, Beatrice; Coniglio, Maria Anna; D'Errico, Marcello Mario; Delia, Santi Antonino; Deriu, Maria Grazia; Guida, Marco; Laganà, Pasqualina; Liguori, Giorgio; Moro, Matteo; Mura, Ida; Pennino, Francesca; Privitera, Gaetano; Romano Spica, Vincenzo; Sembeni, Silvia; Spagnolo, Anna Maria; Tardivo, Stefano; Torre, Ida; Valeriani, Federica; Albertini, Roberto; Pasquarella, Cesira
2017-06-22
Healthcare facilities (HF) represent an at-risk environment for legionellosis transmission occurring after inhalation of contaminated aerosols. In general, the control of water is preferred to that of air because, to date, there are no standardized sampling protocols. Legionella air contamination was investigated in the bathrooms of 11 HF by active sampling (Surface Air System and Coriolis ® μ) and passive sampling using settling plates. During the 8-hour sampling, hot tap water was sampled three times. All air samples were evaluated using culture-based methods, whereas liquid samples collected using the Coriolis ® μ were also analyzed by real-time PCR. Legionella presence in the air and water was then compared by sequence-based typing (SBT) methods. Air contamination was found in four HF (36.4%) by at least one of the culturable methods. The culturable investigation by Coriolis ® μ did not yield Legionella in any enrolled HF. However, molecular investigation using Coriolis ® μ resulted in eight HF testing positive for Legionella in the air. Comparison of Legionella air and water contamination indicated that Legionella water concentration could be predictive of its presence in the air. Furthermore, a molecular study of 12 L. pneumophila strains confirmed a match between the Legionella strains from air and water samples by SBT for three out of four HF that tested positive for Legionella by at least one of the culturable methods. Overall, our study shows that Legionella air detection cannot replace water sampling because the absence of microorganisms from the air does not necessarily represent their absence from water; nevertheless, air sampling may provide useful information for risk assessment. The liquid impingement technique appears to have the greatest capacity for collecting airborne Legionella if combined with molecular investigations.
Montagna, Maria Teresa; De Giglio, Osvalda; Cristina, Maria Luisa; Napoli, Christian; Pacifico, Claudia; Agodi, Antonella; Baldovin, Tatjana; Casini, Beatrice; Coniglio, Maria Anna; D’Errico, Marcello Mario; Delia, Santi Antonino; Deriu, Maria Grazia; Guida, Marco; Laganà, Pasqualina; Liguori, Giorgio; Moro, Matteo; Mura, Ida; Pennino, Francesca; Privitera, Gaetano; Romano Spica, Vincenzo; Sembeni, Silvia; Spagnolo, Anna Maria; Tardivo, Stefano; Torre, Ida; Valeriani, Federica; Albertini, Roberto; Pasquarella, Cesira
2017-01-01
Healthcare facilities (HF) represent an at-risk environment for legionellosis transmission occurring after inhalation of contaminated aerosols. In general, the control of water is preferred to that of air because, to date, there are no standardized sampling protocols. Legionella air contamination was investigated in the bathrooms of 11 HF by active sampling (Surface Air System and Coriolis®μ) and passive sampling using settling plates. During the 8-hour sampling, hot tap water was sampled three times. All air samples were evaluated using culture-based methods, whereas liquid samples collected using the Coriolis®μ were also analyzed by real-time PCR. Legionella presence in the air and water was then compared by sequence-based typing (SBT) methods. Air contamination was found in four HF (36.4%) by at least one of the culturable methods. The culturable investigation by Coriolis®μ did not yield Legionella in any enrolled HF. However, molecular investigation using Coriolis®μ resulted in eight HF testing positive for Legionella in the air. Comparison of Legionella air and water contamination indicated that Legionella water concentration could be predictive of its presence in the air. Furthermore, a molecular study of 12 L. pneumophila strains confirmed a match between the Legionella strains from air and water samples by SBT for three out of four HF that tested positive for Legionella by at least one of the culturable methods. Overall, our study shows that Legionella air detection cannot replace water sampling because the absence of microorganisms from the air does not necessarily represent their absence from water; nevertheless, air sampling may provide useful information for risk assessment. The liquid impingement technique appears to have the greatest capacity for collecting airborne Legionella if combined with molecular investigations. PMID:28640202
Corzo, Cesar A; Culhane, Marie; Dee, Scott; Morrison, Robert B; Torremorell, Montserrat
2013-01-01
Airborne transmission of influenza A virus (IAV) in swine is speculated to be an important route of virus dissemination, but data are scarce. This study attempted to detect and quantify airborne IAV by virus isolation and RRT-PCR in air samples collected under field conditions. This was accomplished by collecting air samples from four acutely infected pig farms and locating air samplers inside the barns, at the external exhaust fans and downwind from the farms at distances up to 2.1 km. IAV was detected in air samples collected in 3 out of 4 farms included in the study. Isolation of IAV was possible from air samples collected inside the barn at two of the farms and in one farm from the exhausted air. Between 13% and 100% of samples collected inside the barns tested RRT-PCR positive with an average viral load of 3.20E+05 IAV RNA copies/m³ of air. Percentage of exhaust positive air samples also ranged between 13% and 100% with an average viral load of 1.79E+04 RNA copies/m³ of air. Influenza virus RNA was detected in air samples collected between 1.5 and 2.1 Km away from the farms with viral levels significantly lower at 4.65E+03 RNA copies/m³. H1N1, H1N2 and H3N2 subtypes were detected in the air samples and the hemagglutinin gene sequences identified in the swine samples matched those in aerosols providing evidence that the viruses detected in the aerosols originated from the pigs in the farms under study. Overall our results indicate that pigs can be a source of IAV infectious aerosols and that these aerosols can be exhausted from pig barns and be transported downwind. The results from this study provide evidence of the risk of aerosol transmission in pigs under field conditions.
Corzo, Cesar A.; Culhane, Marie; Dee, Scott; Morrison, Robert B.; Torremorell, Montserrat
2013-01-01
Airborne transmission of influenza A virus (IAV) in swine is speculated to be an important route of virus dissemination, but data are scarce. This study attempted to detect and quantify airborne IAV by virus isolation and RRT-PCR in air samples collected under field conditions. This was accomplished by collecting air samples from four acutely infected pig farms and locating air samplers inside the barns, at the external exhaust fans and downwind from the farms at distances up to 2.1 km. IAV was detected in air samples collected in 3 out of 4 farms included in the study. Isolation of IAV was possible from air samples collected inside the barn at two of the farms and in one farm from the exhausted air. Between 13% and 100% of samples collected inside the barns tested RRT-PCR positive with an average viral load of 3.20E+05 IAV RNA copies/m3 of air. Percentage of exhaust positive air samples also ranged between 13% and 100% with an average viral load of 1.79E+04 RNA copies/m3 of air. Influenza virus RNA was detected in air samples collected between 1.5 and 2.1 Km away from the farms with viral levels significantly lower at 4.65E+03 RNA copies/m3. H1N1, H1N2 and H3N2 subtypes were detected in the air samples and the hemagglutinin gene sequences identified in the swine samples matched those in aerosols providing evidence that the viruses detected in the aerosols originated from the pigs in the farms under study. Overall our results indicate that pigs can be a source of IAV infectious aerosols and that these aerosols can be exhausted from pig barns and be transported downwind. The results from this study provide evidence of the risk of aerosol transmission in pigs under field conditions. PMID:23951164
Luksamijarulkul, Pipat; Sundhiyodhin, Viboonsri; Luksamijarulkul, Soavalug; Kaewboonchoo, Orawan
2004-06-01
The air quality in mass transport buses, especially air-conditioned buses may affect bus drivers who work full time. Bus numbers 16, 63, 67 and 166 of the Seventh Bus Zone of Bangkok Mass Transit Authority were randomly selected to investigate for microbial air quality. Nine air-conditioned buses and 2-4 open-air buses for each number of the bus (36 air-conditioned buses and 12 open-air buses) were included. Five points of in-bus air samples in each studied bus were collected by using the Millipore A ir Tester Totally, 180 and 60 air samples collected from air-conditioned buses and open-air buses were cultured for bacterial and fungal counts. The bus drivers who drove the studied buses were interviewed towards histories of work-related illness while working. The results revealed that the mean +/- SD of bacterial counts in the studied open-air buses ranged from 358.50 +/- 146.66 CFU/m3 to 506 +/- 137.62 CFU/m3; bus number 16 had the highest level. As well as the mean +/- SD of fungal counts which ranged from 93.33 +/- 44.83 CFU/m3 to 302 +/- 294.65 CFU/m3; bus number 166 had the highest level. Whereas, the mean +/- SD of bacterial counts in the studied air-conditioned buses ranged from 115.24 +/- 136.01 CFU/m3 to 244.69 +/- 234.85 CFU/m3; bus numbers 16 and 67 had the highest level. As well as the mean +/- SD of fungal counts which rangedfrom 18.84 +/- 39.42 CFU/m3 to 96.13 +/- 234.76 CFU/m3; bus number 166 had the highest level. When 180 and 60 studied air samples were analyzed in detail, it was found that 33.33% of the air samples from open-air buses and 6.11% of air samples from air-conditioned buses had a high level of bacterial counts (> 500 CFU/m3) while 6.67% of air samples from open-air buses and 2.78% of air samples from air-conditioned buses had a high level of fungal counts (> 500 CFU/m3). Data from the history of work-related illnesses among the studied bus drivers showed that 91.67% of open-air bus drivers and 57.28% of air-conditioned bus drivers had symptoms of work-related illnesses, p = 0.0185.
Contains the Air Sampling Logbook between 1-24-2011 thru 1-28-2011 from the Region 4 Yellow Bluff Air Study Wilcox County, Alabama SESD Project Identification Number:11-0068 November 2010-December 2010
NHEXAS PHASE I ARIZONA STUDY--METALS IN AIR ANALYTICAL RESULTS
The Metals in Air data set contains analytical results for measurements of up to 11 metals in 369 air samples over 175 households. Samples were taken by pumping standardized air volumes through filters at indoor and outdoor sites around each household being sampled. The primary...
U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--METALS IN AIR ANALYTICAL RESULTS
The Metals in Air data set contains analytical results for measurements of up to 11 metals in 344 air samples over 86 households. Samples were taken by pumping standardized air volumes through filters at indoor and outdoor sites around each household being sampled. The primary ...
The purpose of this SOP is to describe the procedures for pre-cleaning filters and polyurethane foam (PUF) plug prior to air sampling with these media. The sampling media are used for sampling indoor air, outdoor air, and personal air. This procedure was followed to ensure consi...
Formaldehyde Exposures in a University Anatomy Laboratory
NASA Astrophysics Data System (ADS)
Winkler, Kyle William
Air sampling studies were conducted within a university anatomical laboratory during the embalmment of a cadaver in order to determine if dangerous concentrations of formaldehyde existed. Three air sampling studies were conducted in the anatomical laboratory on three separate days that a cadaver was being embalmed. Samples were collected and analyzed using the Occupational Safety and Health Administration (OSHA) Sampling and Analytical Methods: Method 52. Each air sampling study sampled for short term exposure limit (STEL) and time weighted mean (TWA) breathing zone formaldehyde concentrations as well as area TWA formaldehyde concentrations. A personal aldehyde monitor was also used in each air sampling study to sample for breathing zone formaldehyde concentrations. Measured TWA mean exposures to formaldehyde ranged from 0.15--1.3 parts per million (ppm), STEL formaldehyde exposures ranged from 0.019--0.64 ppm, and eight-hour TWAs ranged from 0.03 to 3.6 ppm. All 8-hour TWA formaldehyde concentrations sampled in the anatomy laboratory during an embalmment were less than the permissible exposure limit (PEL) required by OSHA.
Study on the impact of industrial flue gases on the PCDD/Fs congener profile in ambient air.
Węgiel, Małgorzata; Chrząszcz, Ryszard; Maślanka, Anna; Grochowalski, Adam
2014-11-01
The aim of this study was to examine the impact of emissions from combustion processes from sinter, medical, waste and sewage waste incineration plants on the PCDD and PCDF congener profile in ambient air in Krakow (city in Poland). The subject matter of the study were air samples from the outskirts and the city center. It was found that in flue gases from industrial sources and in ambient air the share of PCDF congeners in relation to the total content of PCDD/Fs was higher than the share of PCDDs. However, in air samples collected in the city center, this relationship was reversed. The PCDD congener profiles in flue gases and in air samples are comparable. However, in the samples from the city centre, the share of OCDD is significantly higher and amounts to about 80%. The PCDF congener shares show higher spatial diversity, although in all the analyzed air samples, ODCF and 1,2,3,4,6,7,8 HpCDF dominated. Analyzing the share of congeners in regard to the sum of PCDDs/Fs a mutual resemblance of air from the suburbs, exhaust gases from the sinter ore and sewage sludge incinerator plant was observed. The study showed a similarity between the profile of congeners in air from the city centre and exhaust gases from the medical waste incinerator. Copyright © 2014 Elsevier Ltd. All rights reserved.
Tang, Hongmao; Beg, Khaliq R.; Al-Otaiba, Yousef
2006-01-01
Kuwait experiences desert climatic weather. Due to the extreme hot and dry conditions in this country, some analytical phenomena have been discovered. Therefore, a systematic study of sampling and analyzing volatile organic compounds in air by using GC-MS with a cryogenic trap is reported in this paper. This study included comparisons of using different sample containers such as Tedlar bags and SUMMA canisters, and different cryogenic freezing-out air volumes in the trap. Calibration curves for different compounds and improvement of replicated analysis results were also reported here. The study found that using different sample containers produced different results. Analysis of ambient air samples collected in Tedlar bags obtained several volatile organic compounds with large concentrations compared to using SUMMA canisters. Therefore, to choose a sample container properly is a key element for successfully completing a project. Because GC-MS with a cryogenic trap often generates replicated results with poor agreement, an internal standard added to gas standards and air samples by using a gas syringe was tested. The study results proved that it helped to improve the replicated results. PMID:16699723
Tang, Hongmao; Beg, Khaliq R; Al-Otaiba, Yousef
2006-05-12
Kuwait experiences desert climatic weather. Due to the extreme hot and dry conditions in this country, some analytical phenomena have been discovered. Therefore, a systematic study of sampling and analyzing volatile organic compounds in air by using GC-MS with a cryogenic trap is reported in this paper. This study included comparisons of using different sample containers such as Tedlar bags and SUMMA canisters, and different cryogenic freezing-out air volumes in the trap. Calibration curves for different compounds and improvement of replicated analysis results were also reported here. The study found that using different sample containers produced different results. Analysis of ambient air samples collected in Tedlar bags obtained several volatile organic compounds with large concentrations compared to using SUMMA canisters. Therefore, to choose a sample container properly is a key element for successfully completing a project. Because GC-MS with a cryogenic trap often generates replicated results with poor agreement, an internal standard added to gas standards and air samples by using a gas syringe was tested. The study results proved that it helped to improve the replicated results.
Coupe, R H; Manning, M A; Foreman, W T; Goolsby, D A; Majewski, M S
2000-04-05
In April 1995, the US Geological Survey began a study to determine the occurrence and temporal distribution of 49 pesticides and pesticide metabolites in air and rain samples from an urban and an agricultural sampling site in Mississippi. The study was a joint effort between the National Water-Quality Assessment and the Toxic Substances Programs and was part of a larger study examining the occurrence and temporal distribution of pesticides in air and rain in the Mississippi River basin. Concurrent high-volume air and wet-only deposition samples were collected weekly. The air samplers consisted of a glass-fiber filter to collect particles and tandem polyurethane foam plugs to collect gas-phase pesticides. Every rain and air sample collected from the urban and agricultural sites had detectable levels of multiple pesticides. The magnitude of the total concentration was 5-10 times higher at the agricultural site as compared to the urban site. The pesticide with the highest concentration in rain at both sites was methyl parathion. The pesticide with the highest concentration in the air samples from the agricultural site was also methyl parathion, but from the urban site the highest concentration was diazinon followed closely by chlorpyrifos. More than two decades since p,p'-DDT was banned from use in the United States, p,p'-DDE, a metabolite of p,p'-DDT, was detected in every air sample collected from the agricultural site and in more than half of the air samples from the urban site.
Coupe, R.H.; Manning, M.A.; Foreman, W.T.; Goolsby, D.A.; Majewski, M.S.
2000-01-01
In April 1995, the US Geological Survey began a study to determine the occurrence and temporal distribution of 49 pesticides and pesticide metabolites in air and rain samples from an urban and an agricultural sampling site in Mississippi. The study was a joint effort between the National Water-Quality Assessment and the Toxic Substances Programs and was part of a larger study examining the occurrence and temporal distribution of pesticides in air and rain in the Mississippi River basin. Concurrent high-volume air and wet-only deposition samples were collected weekly. The air samplers consisted of a glass-fiber filter to collect particles and tandem polyurethane foam plugs to collect gas-phase pesticides. Every rain and air sample collected from the urban and agricultural sites had detectable levels of multiple pesticides. The magnitude of the total concentration was 5-10 times higher at the agricultural site as compared to the urban site. The pesticide with the highest concentration in rain at both sites was methyl parathion. The pesticide with the highest concentration in the air samples from the agricultural site was also methyl parathion, but from the urban site the highest concentration was diazinon followed closely by chlorpyrifos. More than two decades since p,p'-DDT was banned from use in the United States, p,p'-DDE, a metabolite of p,p'-DDT, was detected in every air sample collected from the agricultural site and in more than half of the air samples from the urban site. Copyright (C) 2000 Elsevier Science B.V.
NHEXAS PHASE I MARYLAND STUDY--PAHS IN AIR ANALYTICAL RESULTS
The PAHs in Air data set contains analytical results for measurements of up to 11 PAHs in 127 air samples over 51 households. Twenty-four-hour samples were taken over a one-week period using a continuous pump and solenoid apparatus pumping a standardized air volume through an UR...
NHEXAS PHASE I MARYLAND STUDY--METALS IN AIR ANALYTICAL RESULTS
The Metals in Air data set contains analytical results for measurements of up to 4 metals in 458 air samples over 79 households. Twenty-four-hour samples were taken over a one-week period using a continuous pump and solenoid apparatus by pumping a standardized air volume through...
NHEXAS PHASE I MARYLAND STUDY--PESTICIDES IN AIR ANALYTICAL RESULTS
The Pesticides in Air data set contains analytical results for measurements of up to 9 pesticides in 127 air samples over 51 households. Samples were taken by pumping standardized air volumes through URG impactors with a 10 um cutpoint and polyurethane foam (PUF) filters at indo...
PCBs were used extensively in school building materials (caulk and lighting fixture ballasts) during the approximate period of 1950-1978. Most of the schools built nationwide during this period have not had indoor air sampling conducted for PCBs. Passive air sampling holds promi...
Diffusive sampling of a mixture of 42 volatile organic compounds (VOCs) in humidified, purified air onto the solid adsorbent Carbopack X was evaluated under controlled laboratory conditions. The evaluation included variations in sample air temperature, relative humidity, and ozon...
Catto, Cyril; Sabrina, Simard; Ginette, Charest-Tardif; Manuel, Rodriguez; Robert, Tardif
2012-01-01
In order to improve disinfection by-product (DBP) exposure assessment, this study was designed to document both water and air levels of these chemical contaminants in two indoor swimming pools and to analyze their within-day and day-to-day variations in both of them. Intensive sampling was carried out during two one-week campaigns to measure trihalomethanes (THMs) and chloramines (CAMs) in water and air, and haloacetic acids (HAAs) in water several times daily. Water samples were systematically collected at three locations in each pool and air samples were collected at various heights around the pool and in other rooms (e.g., changing room) in the buildings. In addition, the ability of various models to predict air concentrations from water was tested using this database. No clear trends, but actual variations of contamination levels, appeared for both water and air according to the sampling locations and times. Likewise, the available models resulted in realistic but imprecise estimates of air contamination levels from water. This study supports the recommendation that suitable minimal air and water sampling should be carried out in swimming pools to assess exposure to DBPs. PMID:23066383
Fogwater Chemistry and Air Quality in the Texas-Louisiana Gulf Coast Corridor
NASA Astrophysics Data System (ADS)
Kommalapati, R. R.; Raja, S.; Ravikrishna, R.; Murugesan, K.; Collett, J. L.; Valsaraj, K.
2007-05-01
The presence of fog water in polluted atmosphere can influence atmospheric chemistry and air quality. The study of interactions between fog water and atmospheric gases and aerosols are very important in understanding the atmospheric fate of the pollutants. In this Study several air samples and fogwater samples were collected in the heavily industrialized area of Gulf Coast corridor( Houston, TX and Baton Rouge, LA). A total of 32 fogwater samples were collected, comprising of nine fog events in Baton Rouge (Nov 2004 to Feb 2005) and two fog events in Houston (Feb, 2006), during the fog sampling campaigns. These samples were analyzed for pH, total and dissolved carbon, major inorganic ions, organic acids, and aromatics, aldehydes, VOCs, and linear alkanes organic compounds. Fogwater samples collected in Houston show clear influence of marine and anthropogenic environment, while Baton Rouge samples reveal a relatively less polluted environment. Also, a time series observation of air samples indicated that fog event at the monitoring site impacted the air concentrations of the pollutants. This is attributed to presence of surface active organic matter in fog water.
Liu, Huan; Zhang, Xu; Zhang, Hao; Yao, Xiangwu; Zhou, Meng; Wang, Jiaqi; He, Zhanfei; Zhang, Huihui; Lou, Liping; Mao, Weihua; Zheng, Ping; Hu, Baolan
2018-02-01
In recent years, air pollution events have occurred frequently in China during the winter. Most studies have focused on the physical and chemical composition of polluted air. Some studies have examined the bacterial bioaerosols both indoors and outdoors. But few studies have focused on the relationship between air pollution and bacteria, especially pathogenic bacteria. Airborne PM samples with different diameters and different air quality index values were collected in Hangzhou, China from December 2014 to January 2015. High-throughput sequencing of 16S rRNA was used to categorize the airborne bacteria. Based on the NCBI database, the "Human Pathogen Database" was established, which is related to human health. Among all the PM samples, the diversity and concentration of total bacteria were lowest in the moderately or heavily polluted air. However, in the PM2.5 and PM10 samples, the relative abundances of pathogenic bacteria were highest in the heavily and moderately polluted air respectively. Considering the PM samples with different particle sizes, the diversities of total bacteria and the proportion of pathogenic bacteria in the PM10 samples were different from those in the PM2.5 and TSP samples. The composition of PM samples with different sizes range may be responsible for the variances. The relative humidity, carbon monoxide and ozone concentrations were the main factors, which affected the diversity of total bacteria and the proportion of pathogenic bacteria. Among the different environmental samples, the compositions of the total bacteria were very similar in all the airborne PM samples, but different from those in the water, surface soil, and ground dust samples. Which may be attributed to that the long-distance transport of the airflow may influence the composition of the airborne bacteria. This study of the pathogenic bacteria in airborne PM samples can provide a reference for environmental and public health researchers. Copyright © 2017 Elsevier Ltd. All rights reserved.
Molecular comparison of the sampling efficiency of four types of airborne bacterial samplers.
Li, Kejun
2011-11-15
In the present study, indoor and outdoor air samples were collected using four types of air samplers often used for airborne bacterial sampling. These air samplers included two solid impactors (BioStage and RCS), one liquid impinger (BioSampler), and one filter sampler with two kinds of filters (a gelatin and a cellulose acetate filter). The collected air samples were further processed to analyze the diversity and abundance of culturable bacteria and total bacteria through standard culture techniques, denaturing gradient gel electrophoresis (DGGE) fingerprinting and quantitative polymerase chain reaction (qPCR) analysis. The DGGE analysis indicated that the air samples collected using the BioStage and RCS samplers have higher culturable bacterial diversity, whereas the samples collected using the BioSampler and the cellulose acetate filter sampler have higher total bacterial diversity. To obtain more information on the sampled bacteria, some gel bands were excised and sequenced. In terms of sampling efficiency, results from the qPCR tests indicated that the collected total bacterial concentration was higher in samples collected using the BioSampler and the cellulose acetate filter sampler. In conclusion, the sampling bias and efficiency of four kinds of air sampling systems were compared in the present study and the two solid impactors were concluded to be comparatively efficient for culturable bacterial sampling, whereas the liquid impactor and the cellulose acetate filter sampler were efficient for total bacterial sampling. Copyright © 2011 Elsevier B.V. All rights reserved.
Nicolaisen, Mogens; West, Jonathan S; Sapkota, Rumakanta; Canning, Gail G M; Schoen, Cor; Justesen, Annemarie F
2017-01-01
Information on the diversity of fungal spores in air is limited, and also the content of airborne spores of fungal plant pathogens is understudied. In the present study, a total of 152 air samples were taken from rooftops at urban settings in Slagelse, DK, Wageningen NL, and Rothamsted, UK together with 41 samples from above oilseed rape fields in Rothamsted. Samples were taken during 10-day periods in spring and autumn, each sample representing 1 day of sampling. The fungal content of samples was analyzed by metabarcoding of the fungal internal transcribed sequence 1 (ITS1) and by qPCR for specific fungi. The metabarcoding results demonstrated that season had significant effects on airborne fungal communities. In contrast, location did not have strong effects on the communities, even though locations were separated by up to 900 km. Also, a number of plant pathogens had strikingly similar patterns of abundance at the three locations. Rooftop samples were more diverse than samples taken above fields, probably reflecting greater mixing of air from a range of microenvironments for the rooftop sites. Pathogens that were known to be present in the crop were also found in air samples taken above the field. This paper is one of the first detailed studies of fungal composition in air with the focus on plant pathogens and shows that it is possible to detect a range of pathogens in rooftop air samplers using metabarcoding.
Weisel, Clifford P; Zhang, Junfeng; Turpin, Barbara J; Morandi, Maria T; Colome, Steven; Stock, Thomas H; Spektor, Dalia M; Korn, Leo; Winer, Arthur; Alimokhtari, Shahnaz; Kwon, Jaymin; Mohan, Krishnan; Harrington, Robert; Giovanetti, Robert; Cui, William; Afshar, Masoud; Maberti, Silvia; Shendell, Derek
2005-03-01
The Relationship of Indoor, Outdoor and Personal Air (RIOPA) Study was undertaken to evaluate the contribution of outdoor sources of air toxics, as defined in the 1990 Clean Air Act Amendments, to indoor concentrations and personal exposures. The concentrations of 18 volatile organic compounds (VOCs), 17 carbonyl compounds, and fine particulate matter mass (PM(2.5)) were measured using 48-h outdoor, indoor and personal air samples collected simultaneously. PM2.5 mass, as well as several component species (elemental carbon, organic carbon, polyaromatic hydrocarbons and elemental analysis) were also measured; only PM(2.5) mass is reported here. Questionnaires were administered to characterize homes, neighborhoods and personal activities that might affect exposures. The air exchange rate was also measured in each home. Homes in close proximity (<0.5 km) to sources of air toxics were preferentially (2:1) selected for sampling. Approximately 100 non-smoking households in each of Elizabeth, NJ, Houston, TX, and Los Angeles, CA were sampled (100, 105, and 105 respectively) with second visits performed at 84, 93, and 81 homes in each city, respectively. VOC samples were collected at all homes, carbonyls at 90% and PM(2.5) at 60% of the homes. Personal samples were collected from nonsmoking adults and a portion of children living in the target homes. This manuscript provides the RIOPA study design and quality control and assurance data. The results from the RIOPA study can potentially provide information on the influence of ambient sources on indoor air concentrations and exposure for many air toxics and will furnish an opportunity to evaluate exposure models for these compounds.
Presence of organophosphorus pesticide oxygen analogs in air samples
NASA Astrophysics Data System (ADS)
Armstrong, Jenna L.; Fenske, Richard A.; Yost, Michael G.; Galvin, Kit; Tchong-French, Maria; Yu, Jianbo
2013-02-01
A number of recent toxicity studies have highlighted the increased potency of oxygen analogs (oxons) of several organophosphorus (OP) pesticides. These findings were a major concern after environmental oxons were identified in environmental samples from air and surfaces following agricultural spray applications in California and Washington State. This paper reports on the validity of oxygen analog measurements in air samples for the OP pesticide, chlorpyrifos. Controlled environmental and laboratory experiments were used to examine artificial formation of chlorpyrifos-oxon using OSHA Versatile Sampling (OVS) tubes as recommended by NIOSH method 5600. Additionally, we compared expected chlorpyrifos-oxon attributable to artificial transformation to observed chlorpyrifos-oxon in field samples from a 2008 Washington State Department of Health air monitoring study using non-parametric statistical methods. The amount of artificially transformed oxon was then modeled to determine the amount of oxon present in the environment. Toxicity equivalency factors (TEFs) for chlorpyrifos-oxon were used to calculate chlorpyrifos-equivalent air concentrations. The results demonstrate that the NIOSH-recommended sampling matrix (OVS tubes with XAD-2 resin) was found to artificially transform up to 30% of chlorpyrifos to chlorpyrifos-oxon, with higher percentages at lower concentrations (<30 ng m-3) typical of ambient or residential levels. Overall, the 2008 study data had significantly greater oxon than expected by artificial transformation, but the exact amount of environmental oxon in air remains difficult to quantify with the current sampling method. Failure to conduct laboratory analysis for chlorpyrifos-oxon may result in underestimation of total pesticide concentration when using XAD-2 resin matrices for occupational or residential sampling. Alternative methods that can accurately measure both OP pesticides and their oxygen analogs should be used for air sampling, and a toxicity equivalent factor approach should be used to determine potential health risks from exposures.
Evaluating fungal contamination indoors is complicated because of the many different sampling methods utilized. In this study, fungal contamination was evaluated using five sampling methods and four matrices for results. The five sampling methods were a 48 hour indoor air sample ...
A metagenomic framework for the study of airborne microbial communities.
Yooseph, Shibu; Andrews-Pfannkoch, Cynthia; Tenney, Aaron; McQuaid, Jeff; Williamson, Shannon; Thiagarajan, Mathangi; Brami, Daniel; Zeigler-Allen, Lisa; Hoffman, Jeff; Goll, Johannes B; Fadrosh, Douglas; Glass, John; Adams, Mark D; Friedman, Robert; Venter, J Craig
2013-01-01
Understanding the microbial content of the air has important scientific, health, and economic implications. While studies have primarily characterized the taxonomic content of air samples by sequencing the 16S or 18S ribosomal RNA gene, direct analysis of the genomic content of airborne microorganisms has not been possible due to the extremely low density of biological material in airborne environments. We developed sampling and amplification methods to enable adequate DNA recovery to allow metagenomic profiling of air samples collected from indoor and outdoor environments. Air samples were collected from a large urban building, a medical center, a house, and a pier. Analyses of metagenomic data generated from these samples reveal airborne communities with a high degree of diversity and different genera abundance profiles. The identities of many of the taxonomic groups and protein families also allows for the identification of the likely sources of the sampled airborne bacteria.
A Metagenomic Framework for the Study of Airborne Microbial Communities
Tenney, Aaron; McQuaid, Jeff; Williamson, Shannon; Thiagarajan, Mathangi; Brami, Daniel; Zeigler-Allen, Lisa; Hoffman, Jeff; Goll, Johannes B.; Fadrosh, Douglas; Glass, John; Adams, Mark D.; Friedman, Robert; Venter, J. Craig
2013-01-01
Understanding the microbial content of the air has important scientific, health, and economic implications. While studies have primarily characterized the taxonomic content of air samples by sequencing the 16S or 18S ribosomal RNA gene, direct analysis of the genomic content of airborne microorganisms has not been possible due to the extremely low density of biological material in airborne environments. We developed sampling and amplification methods to enable adequate DNA recovery to allow metagenomic profiling of air samples collected from indoor and outdoor environments. Air samples were collected from a large urban building, a medical center, a house, and a pier. Analyses of metagenomic data generated from these samples reveal airborne communities with a high degree of diversity and different genera abundance profiles. The identities of many of the taxonomic groups and protein families also allows for the identification of the likely sources of the sampled airborne bacteria. PMID:24349140
Fang, Guor-Cheng; Lin, Yen-Heng; Zheng, Yu-Cheng
2016-02-01
The main purpose of this study was to monitor ambient air particles and particulate-bound mercury Hg(p) in total suspended particulate (TSP) concentrations and dry deposition at the Hung Kuang (Traffic), Taichung airport and Westing Park sampling sites during the daytime and nighttime, from 2011 to 2012. In addition, the calculated/measured dry deposition flux ratios of ambient air particles and particulate-bound mercury Hg(p) were also studied with Baklanov & Sorensen and the Williams models. For a particle size of 10 μm, the Baklanov & Sorensen model yielded better predictions of dry deposition of ambient air particulates and particulate-bound mercury Hg(p) at the Hung Kuang (Traffic), Taichung airport and Westing Park sampling site during the daytime and nighttime sampling periods. However, for particulates with sizes 20-23 μm, the results obtained in the study reveal that the Williams model provided better prediction results for ambient air particulates and particulate-bound mercury Hg(p) at all sampling sites in this study.
Breiman, R F; Cozen, W; Fields, B S; Mastro, T D; Carr, S J; Spika, J S; Mascola, L
1990-06-01
Epidemiologic studies have suggested that legionnaires' disease can be transmitted to susceptible hosts by contaminated aerosolized water from cooling towers and evaporative condensers; however, epidemic strains of Legionella have not been isolated by air sampling at such sites during epidemiologic investigations. An outbreak of legionnaires' disease occurred at a retirement hotel; Legionella pneumophila serogroup 1 was isolated from an evaporative condenser and from potable water. A case-control study showed that the only significant exposure risk was in area A. L. pneumophila serogroup 1 was isolated during air sampling near the evaporative condenser exhaust site, the air conditioning intake vent, and an air vent in area A, but not in shower stalls. Monoclonal antibody subtype patterns of L. pneumophila serogroup 1 isolates from patients matched those from the evaporative condenser but not from shower water. Air sampling and monoclonal antibody subtyping results support epidemiologic evidence that the evaporative condenser was the source of this outbreak.
Beamer, P.I.; Sugeng, A. J.; Kelly, M.D.; Lothrop, N.; Klimecki, W.; Wilkinson, S.T.; Loh, M.
2014-01-01
Mine tailings are a source of metal exposures in many rural communities. Multiple air samples are necessary to assess the extent of exposures and factors contributing to these exposures. However, air sampling equipment is costly and requires trained personnel to obtain measurements, limiting the number of samples that can be collected. Simple, low-cost methods are needed to allow for increased sample collection. The objective of our study was to assess if dust fall filters can serve as passive air samplers and be used to characterize potential exposures in a community near contaminated mine tailings. We placed filters in cylinders, concurrently with active indoor air samplers, in 10 occupied homes. We calculated an estimated flow rate by dividing the mass on each dust fall filter by the bulk air concentration and the sampling duration. The mean estimated flow rate for dust fall filters was significantly different during sampling periods with precipitation. The estimated flow rate was used to estimate metal concentration in the air of these homes, as well as in 31 additional homes in another rural community impacted by contaminated mine tailings. The estimated air concentrations had a significant linear association with the measured air concentrations for beryllium, manganese and arsenic (p<0.05), whose primary source in indoor air is resuspended soil from outdoors. In the second rural community, our estimated metal concentrations in air were comparable to active air sampling measurements taken previously. This passive air sampler is a simple low-cost method to assess potential exposures near contaminated mining sites. PMID:24469149
Composition Alteration of Stratospheric Air Due to Sampling through a Flow Tube.
1984-02-03
C. C. , Forsberg, C. A. , and Pieri , H. V. (19)83) Stratospheric N 20 CF2 Cl and CFCI3 composition studies utilizing in situ cryogenic whole air...Gas-Surface Interactions in Cryogenic Whole Air Sampling, AFGL-TR-81-0162, AD A108255. 19. Gallagher, C. C., Forsberg, C. A., and Pieri , R. V. (1983...Gallagher, C. C., Forsberg, C. A., Pieri , R. V., and Faucher, G. A. (1983a) Oxides of Nitrogen Content of Whole Air Samples Obtained at Altitudes From 12
Miller, J D; Haisley, P D; Reinhardt, J H
2000-09-01
We studied the extent and nature of fungal colonization of building materials in 58 naturally ventilated apartments that had suffered various kinds of water damage in relation to air sampling done before the physical inspections. The results of air samples from each apartment were compared by rank order of species with pooled data from outdoor air. Approximately 90% of the apartments that had significant amounts of fungi in wall cavities were identified by air sampling. There was no difference in the average fungal colony forming unit values per m3 between the 15 apartments with the most fungal contamination and the 15 with the least. In contrast, the prevalence of samples with fungal species significantly different than the pooled outdoor air between the more contaminated versus the less contaminated apartments was approximately 10-fold. We provide information on methods to document fungal contamination in buildings.
Identifying the effective concentration for spatial repellency of the dengue vector Aedes aegypti
2012-01-01
Background Current efforts are underway to quantify the chemical concentration in a treated air space that elicits a spatial repellent (deterrent) response in a vector population. Such information will facilitate identifying the optimum active ingredient (AI) dosage and intervention coverage important for the development of spatial repellent tools – one of several novel strategies being evaluated for vector-borne disease control. This study reports initial findings from air sampling experiments conducted under field conditions to describe the relationship between air concentrations of repellent AIs and deterrent behavior in the dengue vector, Aedes aegypti. Methods Air samples were taken inside and outdoors of experimental huts located in Pu Tuey Village, Kanchanaburi Province, Thailand in conjunction with mosquito behavioral evaluations. A mark-release-recapture study design using interception traps was used to measure deterrency of Ae. aegypti against 0.00625% metofluthrin coils and DDT-treated fabric (2g/m2) within separate experimental trials. Sentinel mosquito cohorts were positioned adjacent to air sampling locations to monitor knock down responses to AI within the treated air space. Air samples were analyzed using two techniques: the U.S. Environmental Protection Agency (USEPA) Compendium Method TO-10A and thermal desorption (TD). Results Both the USEPA TO-10A and TD air sampling methods were able to detect and quantify volatized AIs under field conditions. Air samples indicated concentrations of both repellent chemicals below thresholds required for toxic responses (mortality) in mosquitoes. These concentrations elicited up to a 58% and 70% reduction in Ae. aegypti entry (i.e., deterrency) into treated experimental huts using metofluthrin coils and DDT-treated fabric, respectively. Minimal knock down was observed in sentinel mosquito cohorts positioned adjacent to air sampling locations during both chemical evaluations. Conclusions This study is the first to describe two air sampling methodologies that are appropriate for detecting and quantifying repellent chemicals within a treated air space during mosquito behavior evaluations. Results demonstrate that the quantity of AI detected by the mosquito vector, Ae. aegypti, that elicits repellency is far lower than that needed for toxicity. These findings have important implications for evaluation and optimization of new vector control tools that function through mosquito behavior modification as opposed to mortality. PMID:23273133
Fang, Guor-Cheng; Lin, Yen-Heng; Chang, Chia-Ying; Zheng, Yu-Cheng
2014-08-01
In this investigation, the concentrations of particles in ambient air, gaseous elemental mercury (GEM), and particulate-bound mercury (Hg(p)) in total suspended particulates (TSP) as well as dry deposition at a (Traffic) sampling site at Hung-kuang were studied during the day and night in 2012. The results reveal that the mean concentrations of TSP in ambient air, GEM, and Hg(p) were 69.72 μg/m(3), 3.17, and 0.024 ng/m(3), respectively, at the Hung-kuang (Traffic) sampling site during daytime sampling periods. The results also reveal that the mean rates of dry deposition of particles from ambient air and Hg(p) were 145.20 μg/m(2) min and 0.022 ng/m(2) min, respectively, at the Hung-kuang (Traffic) sampling site during the daytime sampling period. The mean concentrations of TSP in ambient air, GEM, and Hg(p) were 60.56 μg/m(3), 2.74, and 0.018 ng/m(3), respectively, at the Hung-kuang (Traffic) sampling site during the nighttime sampling period. The mean rates of dry deposition of particles and Hg(p) from ambient air were 132.58 μg/m(2) min and 0.016 ng/m(2) min, respectively, at the Hung-kuang (Traffic) sampling site during the nighttime sampling period.
Sample storage-induced changes in the quantity and quality of soil labile organic carbon
Sun, Shou-Qin; Cai, Hui-Ying; Chang, Scott X.; Bhatti, Jagtar S.
2015-01-01
Effects of sample storage methods on the quantity and quality of labile soil organic carbon are not fully understood even though their effects on basic soil properties have been extensively studied. We studied the effects of air-drying and frozen storage on cold and hot water soluble organic carbon (WSOC). Cold- and hot-WSOC in air-dried and frozen-stored soils were linearly correlated with those in fresh soils, indicating that storage proportionally altered the extractability of soil organic carbon. Air-drying but not frozen storage increased the concentrations of cold-WSOC and carbohydrate in cold-WSOC, while both increased polyphenol concentrations. In contrast, only polyphenol concentration in hot-WSOC was increased by air-drying and frozen storage, suggesting that hot-WSOC was less affected by sample storage. The biodegradability of cold- but not hot-WSOC was increased by air-drying, while both air-drying and frozen storage increased humification index and changed specific UV absorbance of both cold- and hot-WSOC, indicating shifts in the quality of soil WSOC. Our results suggest that storage methods affect the quantity and quality of WSOC but not comparisons between samples, frozen storage is better than air-drying if samples have to be stored, and storage should be avoided whenever possible when studying the quantity and quality of both cold- and hot-WSOC. PMID:26617054
The study of volatile organic compounds in urban and indoor air
NASA Astrophysics Data System (ADS)
Clarkson, Paul Jonathan
Chapter 1 is a review of the literature concerning the study of volatile organic compounds in the atmosphere. It examines the basic chemistry of the atmosphere and the roles that organic compounds play in it. Also investigated are the methods of sampling and analysing the volatile organic compounds in the air, paying particular attention to the role of solid phase sampling. Chapter 1 also examines the role of volatile organic compounds on air quality. Chapter 2 describes the experimental procedures that were employed during the course of this research project. Chapter 3 examines a multi-method approach to the study of volatile organic compounds in urban and indoor air. The methods employed were capillary electrophoresis, high performance liquid chromatography and gas chromatography. Although good results were obtained for the various methods that were investigated Chapter 3 concludes that a more unified analytical approach is needed to the study of the air. Chapter 4 investigates the possibilities of using a unified approach to the study of VOC's. This is achieved by the development of an air sampling method that uses solid phase extraction cartridges. By investigating many aspects of air sampling mechanisms the results show that a simple yet efficient method for the sampling of VOC in air has been developed. The SPE method is a reusable, yet reliable method that by using sequential solvent desorption has been shown to exhibit some degree of selectivity. The solid phase that gave the best results was styrene-divinyl benzene however other phases were also investigated. The use of a single gas chromatography method was also investigated for the purpose of confirmatory identification of the VOC's. Various detection systems were used including MS and AED. It was shown that by optimising the GC's it was possible to get complimentary results. Also investigated was the possibility of compound tagging in an attempt to confirm the identity of several of the compounds found in the air. Chapter 5 is a theoretical discussion of the ways presenting the data obtained experimentally in an easy to understand way. Instead of targeting 7 or 8 compounds as being representative of air quality it is argued that by using a technique such as Air Fingerprinting, it is possible to show data that is indicative of the whole air sample. Using actual data it is possible to show the origin of the air sample in a simple yet effective way using air fingerprints.Also discussed is the Individual Component Air Quality Index, this is a method of quantifying air quality. By taking into account compound toxicity, atmospheric lifetime and UV exposure, the ICAQI, it is argued, is a technique that presents a more accurate picture of air quality.Chapter 6 concludes the thesis by drawing together the themes and issues that were raised.
Mendez, Gregory O.; Foreman, William T.; Morita, Andrew; Majewski, Michael S.
2008-01-01
In 1998, the U.S. Geological Survey, in cooperation with the Sweetwater Authority, began a study to monitor water, air, and sediment at the Sweetwater and Loveland Reservoirs in San Diego County, California. The study includes regular sampling of water and air at Sweetwater Reservoir for chemical constituents, including volatile organic compounds (VOC), polynuclear aromatic hydrocarbons (PAH), pesticides, and major and trace elements. The purpose of this study is to monitor changes in contaminant composition and concentration during the construction and operation of State Route 125. To accomplish this, the study was divided into two phases. Phase One sampling (water years 1998–2004) determined baseline conditions for the detection frequency and the concentrations of target compounds in air and water. Phase Two sampling (starting water year 2005) continues at selected monitoring sites during and after construction of State Route 125 to assess the chemical impact this roadway alignment may have on water quality in the reservoir. Water samples were collected for VOCs and pesticides at Loveland Reservoir during Phase One and will be collected during Phase Two for comparison purposes. Air samples collected to monitor changes in VOCs, PAHs, and pesticides were analyzed by adapting methods used to analyze water samples. Bed-sediment samples have been and will be collected three times during the study; at the beginning of Phase One, at the start of Phase Two, and near the end of the study. In addition to the ongoing data collection, several special studies were initiated to assess the occurrence of specific chemicals of concern, such as trace metals, anthropogenic indicator compounds, and pharmaceuticals. This report describes the study design, and the sampling and analytical methods, and presents data from water and air samples collected during the fourth and fifth years of Phase One of the study (October 2001 to September 2003). Data collected during the first three years has been previously published. Three types of quality-control samples were used in this study: blanks, spikes, and replicates. Blanks and spikes are used to estimate result bias, and replicates are used to estimate result variability. Additionally, surrogate compounds were added at the laboratory to samples of VOCs, PAHs, pesticides, anthropogenic indicator compounds, and pharmaceuticals to monitor sample-specific performance of the analytical method.
A STRINGENT COMPARISON OF SAMPLING AND ANALYSIS METHODS FOR VOCS IN AMBIENT AIR
A carefully designed study was conducted during the summer of 1998 to simultaneously collect samples of ambient air by canisters and compare the analysis results to direct sorbent preconcentration results taken at the time of sample collection. A total of 32 1-h sample sets we...
[Legionella spp. contamination in indoor air: preliminary results of an Italian multicenter study].
Montagna, Maria Teresa; De Giglio, Osvalda; Napoli, Christian; Cannova, Lucia; Cristina, Maria Luisa; Deriu, Maria Grazia; Delia, Santi Antonino; Giuliano, Ada; Guida, Marco; Laganà, Pasqualina; Liguori, Giorgio; Mura, Ida; Pennino, Francesca; Rossini, Angelo; Tardivo, Stefano; Torre, Ida; Torregrossa, Maria Valeria; Villafrate, Maria Rosaria; Albertini, Roberto; Pasquarella, Cesira
2014-01-01
To propose a standardized protocol for the evaluation of Legionella contamination in air. A bathroom having a Legionella contamination in water >1,000 cfu/l was selected in 10 different healthcare facilities. Air contamination was assessed by active (Surface Air System, SAS) and passive (Index of Microbial Air, IMA) sampling for 8 hours, about 1 m away from the floor and 50 cm from the tap water. Two hundred liters of air were sampled by SAS every 12 min, after flushing water for 2 min. The IMA value was calculated as the mean value of colony forming units/16 plates exposed during sampling (2 plates/hour). Water contamination was evaluated at T0, after 4 and 8 hours, according to the standard methods. Air contamination by Legionella was found in three healthcare facilities (one with active and two with passive sampling), showing a concomitant tap water contamination (median=40,000; range 1,100-43,000 cfu/l). The remaining seven hospitals isolated Legionella spp. exclusively from water samples (median=8,000; range 1,200-70,000 cfu/l). Our data suggest that environmental Legionella contamination cannot be assessed only through the air sampling, even in the presence of an important water contamination.
Hayes, Robert
2004-10-01
In most nuclear facilities, fixed air samplers and sometimes portable air samplers are used where some probability of a release exists but is not expected, and so the added expense and effort of using a continuous air monitor is not deemed justified. When a release is suspected, naturally occurring radioactive material buildup on the filter typically prevents any quantitative measurements within the first day or so. Likewise, outdoor air measurements suffer from the same limitations (such as those taken during the Los Alamos fires) and so any rapid quantifiable measurements of fixed air sampler/portable air sampler filters which are technically defendable (even though conservative) are of use. The technique presented here is only intended for use in routine health physics survey applications and does not presently appear to be appropriate for sub pico Curie activity determinations. This study evaluates the utility of using a portable continuous air monitor as an alpha spectrometer to make transuranic activity determinations of samples using both the built in algorithm for air monitoring and a simple region of interest analysis. All samples evaluated were from air sample filters taken using a portable air sampler. Samples were taken over many months to quantify effects from natural variation in radon progeny activity distributions.
SOURCES OF EMISSIONS OF POLYCHLORINATED BIPHENYLS INTO THE AMBIENT ATMOSPHERE AND INDOOR AIR
Polychlorinated biphenyls (PCB) have been identified in air samples from many parts of the world since 1960s. This study was undertaken to identify and compare different sources of PCB in indoor and outdoor air. All sampling was performed in central North Carolina. The suspected ...
The objective of the procedure is to collect a representative sample concentration of total airborne fungal spores (viable and non-viable) that may be present in indoor air and in the outdoor air supplied to the space tested.
Araujo, Ricardo; Cabral, João Paulo; Rodrigues, Acácio Gonçalves
2008-03-01
High-efficiency particulate air (HEPA) filters do not completely prevent nosocomial fungal infections. The first aim of this study was to evaluate the impact of different filters and access conditions upon airborne fungi in hospital facilities. Additionally, this study identified fungal indicators of indoor air concentrations. Eighteen rooms and wards equipped with different air filter systems, and access conditions were sampled weekly, during 16 weeks. Tap water samples were simultaneously collected. The overall mean concentration of atmospheric fungi for all wards was 100 colony forming units/m(3). We found a direct proportionality between the levels of the different fungi in the studied atmospheres. Wards with HEPA filters at positive air flow yielded lower fungal levels. Also, the existence of an anteroom and the use of protective clothes were associated to the lowest fungal levels. Principal component analysis showed that penicillia afforded the best separation between wards' air fungal levels. Fungal strains were rarely recovered from tap water samples. In addition to air filtration systems, some access conditions to hospital units, like presence of anteroom and use of protective clothes, may prevent high fungal air load. Penicillia can be used as a general indicator of indoor air fungal levels at Hospital S. João.
Van Nimmen, Nadine F J; Veulemans, Hendrik A F
2004-05-07
A highly sensitive gas chromatographic-mass spectrometric (GC-MS) analytical method for the determination of the opioid narcotics fentanyl, alfentanil, and sufentanil in industrial hygiene personal air samples and surface contamination wipes was developed and comprehensively validated. Sample preparation involved a single step extraction of the samples with methanol, fortified with a fixed amount of the penta-deuterated analogues of the opioid narcotics as internal standard. The GC-MS analytical procedure using selected ion monitoring (SIM) was shown to be highly selective. Linearity was shown for levels of extracted wipe and air samples corresponding to at least 0.1-2 times their surface contamination limit (SCL) and accordingly to 0.1-2 times their time weighted average occupational exposure limit (OEL-TWA) based on a full shift 9601 air sample. Extraction recoveries were determined for spiked air samples and surface wipes and were found to be quantitative for both sampling media in the entire range studied. The air sampling method's limit of detection (LOD) was determined to be 0.4 ng per sample for fentanyl and sufentanil and 1.6 ng per sample for alfentanil, corresponding to less than 1% of their individual OEL for a full shift air sample (9601). The limit of quantification (LOQ) was found to be 1.4, 1.2, and 5.0 ng per filter for fentanyl, sufentanil, and alfentanil, respectively. The wipe sampling method had LODs of 4 ng per wipe for fentanyl and sufentanil and 16 ng per wipe for alfentanil and LOQs of respectively, 14, 12, and 50 ng per wipe. The analytical intra-assay precision of the air sampling and wipe sampling method, defined as the coefficient of variation on the analytical result of six replicate spiked media was below 10 and 5%, respectively, for all opioids at all spike levels. Accuracy expressed as relative error was determined to be below 10%, except for alfentanil at the lowest spike level (-13.1%). The stability of the opioids during simulated air sampling was investigated. For fentanyl and sufentanil a quantitative recovery was observed at all spike levels, while for alfentanil recoveries ranged from 60.3 to 85.4%. When spiked air samples were stored at ambient temperature and at -15 degrees C quantitative recovery was found for fentanyl and sufentanil after 7 and 14 days. For alfentanil a slight loss seemed to occur upon storage during 7 days, being more explicit after 14 days. Ambient storage of spiked wipes seemed to lead to significant losses of all opioids studied, yielding recoveries of 37.7-88.3%. Upon storage of similar wipes at -15 degrees C a significantly higher recovery was found ranging from 77.3 to 88.3%. The developed analytical and sampling procedures have been recently applied in an explorative field study of which the results of surface contamination wipe sampling are presented in this paper. To our knowledge, this is the first study addressing the development and validation of analytical procedures for the assessment of external occupational exposure to potent opioid narcotics.
Molecular detection of airborne Coccidioides in Tucson, Arizona
Chow, Nancy A.; Griffin, Dale W.; Barker, Bridget M.; Loparev, Vladimir N.; Litvintseva, Anastasia P.
2016-01-01
Environmental surveillance of the soil-dwelling fungus Coccidioides is essential for the prevention of Valley fever, a disease primarily caused by inhalation of the arthroconidia. Methods for collecting and detectingCoccidioides in soil samples are currently in use by several laboratories; however, a method utilizing current air sampling technologies has not been formally demonstrated for the capture of airborne arthroconidia. In this study, we collected air/dust samples at two sites (Site A and Site B) in the endemic region of Tucson, Arizona, and tested a variety of air samplers and membrane matrices. We then employed a single-tube nested qPCR assay for molecular detection. At both sites, numerous soil samples (n = 10 at Site A and n = 24 at Site B) were collected and Coccidioides was detected in two samples (20%) at Site A and in eight samples (33%) at Site B. Of the 25 air/dust samples collected at both sites using five different air sampling methods, we detected Coccidioides in three samples from site B. All three samples were collected using a high-volume sampler with glass-fiber filters. In this report, we describe these methods and propose the use of these air sampling and molecular detection strategies for environmental surveillance of Coccidioides.
Magare, B; Nair, A; Khairnar, K
2017-10-01
Development of a simple and economical air sampler for isolation and enrichment of bacteriophages from air samples. A vacuum filtration unit with simple modifications was used for isolation of bacteriophages from air sampled in the lavatory. Air was sampled at the rate of 62 l min -1 by bubbling into Mcllvaine buffer for 30 min, which was used as bacteriophage solution for enrichment and plaque assessment against individual hosts. Alternatively, the aforementioned phage solution was enriched using a host consortium before plaque assessment. Phages were isolated in the range of 1-12 PFU per ml by the first method, whereas enrichment with host consortium gave phages around 10- to 1000-folds higher in number. Combining with established enrichment method, an improvement of about 10 times in phage isolation efficiency was attained. The method is very useful for studying the natural bacteriophages of air, requiring only a basic microbiological laboratory setup making it simple and economical. This study brings out a simple, economical air sampler for assessing air bacteriophages that can be employed by any microbial laboratory. Although various methods are available for studying bacteriophages in water and soil, very limited are available for air. To the best of our knowledge, the method developed in this study is unique in its design and concept for studying bacteriophages in air. The sampler is sterilizable by autoclaving and maintains a healthy rate of airflow provided by conventional vacuum pumps. The use of a nonspecific 'trapping solution' allows for the qualitative and quantitative study of air bacteriophages. © 2017 The Society for Applied Microbiology.
Maskrey, Joshua R; Insley, Allison L; Hynds, Erin S; Panko, Julie M
2016-07-01
A 3-month air monitoring study was conducted in Washington County, Pennsylvania, at the request of local community members regarding the potential risks resulting from air emissions of pollutants related to hydraulic fracturing operations. Continuous air monitoring for total volatile organic compounds was performed at two sampling sites, including a school and a residence, located within 900 m of a hydraulic fracturing well pad that had been drilled prior to the study. Intermittent 24-hour air samples for 62 individual volatile organic compounds were also collected. The ambient air at both sites was monitored during four distinct periods of unconventional natural gas extraction activity: an inactive period prior to fracturing operations, during fracturing operations, during flaring operations, and during another inactive period after operations. The results of the continuous monitoring during fracturing and flaring sampling periods for total volatile organic compounds were similar to the results obtained during inactive periods. Total volatile organic compound 24-hour average concentrations ranged between 0.16 and 80 ppb during all sampling periods. Several individual volatile compounds were detected in the 24-hour samples, but they were consistent with background atmospheric levels measured previously at nearby sampling sites and in other areas in Washington County. Furthermore, a basic yet conservative screening level evaluation demonstrated that the detected volatile organic compounds were well below health-protective levels. The primary finding of this study was that the operation of a hydraulic fracturing well pad in Washington County did not substantially affect local air concentrations of total and individual volatile organic compounds.
NHEXAS PHASE I ARIZONA STUDY--QA ANALYTICAL RESULTS FOR METALS IN BLANK SAMPLES
The Metals in Blank Samples data set contains the analytical results of measurements of up to 27 metals in 82 blank samples from 26 households. Measurements were made in blank samples of dust, indoor and outdoor air, personal air, food, beverages, blood, urine, and dermal wipe r...
Creamer, E; Shore, A C; Deasy, E C; Galvin, S; Dolan, A; Walley, N; McHugh, S; Fitzgerald-Hughes, D; Sullivan, D J; Cunney, R; Coleman, D C; Humphreys, H
2014-03-01
Meticillin-resistant Staphylococcus aureus (MRSA) can be recovered from hospital air and from environmental surfaces. This poses a potential risk of transmission to patients. To investigate associations between MRSA isolates recovered from air and environmental surfaces with those from patients when undertaking extensive patient and environmental sampling. This was a prospective observational study of patients and their environment in eight wards of a 700-bed tertiary care hospital during 2010 and 2011. Sampling of patients, air and surfaces was carried out on all ward bays, with more extended environmental sampling in ward high-dependency bays and at particular times of the day. The genetic relatedness of isolates was determined by DNA microarray profiling and spa typing. MRSA was recovered from 30/706 (4.3%) patients and from 19/132 (14.4%) air samples. On 9/132 (6.8%) occasions both patient and air samples yielded MRSA. In 32 high-dependency bays, MRSA was recovered from 12/161 (7.4%) patients, 8/32 (25%) air samples, and 21/644 (3.3%) environmental surface samples. On 10/132 (7.6%) occasions, MRSA was isolated from air in the absence of MRSA-positive patients. Patient demographic data combined with spa typing and DNA microarray profiling revealed four likely transmission clusters, where patient and environmental isolates were deemed to be very closely related. Air sampling yielded MRSA on frequent occasions, especially in high-dependency bays. Environmental and air sampling combined with patient demographic data, spa typing and DNA microarray profiling indicated the presence of clusters that were not otherwise apparent. Copyright © 2014 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
Air sampling with solid phase microextraction
NASA Astrophysics Data System (ADS)
Martos, Perry Anthony
There is an increasing need for simple yet accurate air sampling methods. The acceptance of new air sampling methods requires compatibility with conventional chromatographic equipment, and the new methods have to be environmentally friendly, simple to use, yet with equal, or better, detection limits, accuracy and precision than standard methods. Solid phase microextraction (SPME) satisfies the conditions for new air sampling methods. Analyte detection limits, accuracy and precision of analysis with SPME are typically better than with any conventional air sampling methods. Yet, air sampling with SPME requires no pumps, solvents, is re-usable, extremely simple to use, is completely compatible with current chromatographic equipment, and requires a small capital investment. The first SPME fiber coating used in this study was poly(dimethylsiloxane) (PDMS), a hydrophobic liquid film, to sample a large range of airborne hydrocarbons such as benzene and octane. Quantification without an external calibration procedure is possible with this coating. Well understood are the physical and chemical properties of this coating, which are quite similar to those of the siloxane stationary phase used in capillary columns. The log of analyte distribution coefficients for PDMS are linearly related to chromatographic retention indices and to the inverse of temperature. Therefore, the actual chromatogram from the analysis of the PDMS air sampler will yield the calibration parameters which are used to quantify unknown airborne analyte concentrations (ppb v to ppm v range). The second fiber coating used in this study was PDMS/divinyl benzene (PDMS/DVB) onto which o-(2,3,4,5,6- pentafluorobenzyl) hydroxylamine (PFBHA) was adsorbed for the on-fiber derivatization of gaseous formaldehyde (ppb v range), with and without external calibration. The oxime formed from the reaction can be detected with conventional gas chromatographic detectors. Typical grab sampling times were as small as 5 seconds. With 300 seconds sampling, the formaldehyde detection limit was 2.1 ppbv, better than any other 5 minute sampling device for formaldehyde. The first-order rate constant for product formation was used to quantify formaldehyde concentrations without a calibration curve. This spot sampler was used to sample the headspace of hair gel, particle board, plant material and coffee grounds for formaldehyde, and other carbonyl compounds, with extremely promising results. The SPME sampling devices were also used for time- weighted average sampling (30 minutes to 16 hours). Finally, the four new SPME air sampling methods were field tested with side-by-side comparisons to standard air sampling methods, showing a tremendous use of SPME as an air sampler.
NASA Astrophysics Data System (ADS)
Lewtas, Joellen; Goto, Sumio; Williams, Katherine; Chuang, Jane C.; Petersen, Bruce A.; Wilson, Nancy K.
The mutagenicity of indoor air paniculate matter has been measured in a pilot field study of homes in Columbus, Ohio during the 1984 winter. The study was conducted in eight all natural-gas homes and two all electric homes. Paniculate matter and semi-volatile organic compounds were collected indoors using a medium volume sampler. A micro-forward mutation bioassay employing Salmonella typhimurium strain TM 677 was used to quantify the mutagenicity in solvent extracts of microgram quantities of indoor air particles. The mutagenicity was quantified in terms of both mutation frequency per mg of organic matter extracted and per cubic meter of air sampled. The combustion source variables explored in this study included woodburning in fireplaces and cigarette smoking. Homes in which cigarette smoking occurred had the highest concentrations of mutagenicity per cubic meter of air. The average indoor air mutagenicity per cubic meter was highly correlated with the number of cigarettes smoked. When the separate sampling periods in each room were compared, the mutagenicity in the kitchen samples was the most highly correlated with the number of cigarettes smoked.
Łukaszuk, Cecylia; Krajewska-Kułak, Elżbieta; Guzowski, Andrzej; Kułak, Wojciech; Kraszyńska, Bogumiła
2017-07-20
Although several air sampling devices for identifying and enumerating airborne microorganisms are commercially available, each poses some limitations. The aim of this study was to evaluate air pollution fungi using three such samplers: SAS Super 100, Microbiological Air Sampler (MAS) 100, and Air IDEAL. Mycological air was taken from the cellars of a 17th-century church in Siemiatycze, Poland, and the nearby outdoor environment. With samplers placed 1.5 m above the floor, microbial flora in air samples collected inside and outside the cellar were detected. The number of colony-forming units (CFU) of fungi obtained with the three samplers from the cellars and outdoor environment differed; the most CFU were obtained with the Air IDEAL and the least with the SAS Super 100. Significant differences emerged in CFUs collected from air samples with the MAS 100 and SAS Super 100, on the one hand, and the SAS Super 100 and Air IDEAL, on the other. Otherwise, results among the samplers were different. More Cladosporium species were collected with the MAS 100 sampler, whereas more Fusarium and Aspergillus species were collected with the Air IDEAL sampler. Significant differences among CFU/m³ values among the tested sites depended on the sampler used.
Manganese (Mn) is ubiquitous in the environment and essential for normal growth and development, yet excessive exposure can lead to impairments in neurological function. This study modeled ambient Mn concentrations as an alternative to stationary and personal air sampling to asse...
A simple novel device for air sampling by electrokinetic capture
Gordon, Julian; Gandhi, Prasanthi; Shekhawat, Gajendra; ...
2015-12-27
A variety of different sampling devices are currently available to acquire air samples for the study of the microbiome of the air. All have a degree of technical complexity that limits deployment. Here, we evaluate the use of a novel device, which has no technical complexity and is easily deployable. An air-cleaning device powered by electrokinetic propulsion has been adapted to provide a universal method for collecting samples of the aerobiome. Plasma-induced charge in aerosol particles causes propulsion to and capture on a counter-electrode. The flow of ions creates net bulk airflow, with no moving parts. A device and electrodemore » assembly have been re-designed from air-cleaning technology to provide an average air flow of 120 lpm. This compares favorably with current air sampling devices based on physical air pumping. Capture efficiency was determined by comparison with a 0.4 μm polycarbonate reference filter, using fluorescent latex particles in a controlled environment chamber. Performance was compared with the same reference filter method in field studies in three different environments. For 23 common fungal species by quantitative polymerase chain reaction (qPCR), there was 100 % sensitivity and apparent specificity of 87%, with the reference filter taken as “gold standard.” Further, bacterial analysis of 16S RNA by amplicon sequencing showed equivalent community structure captured by the electrokinetic device and the reference filter. Unlike other current air sampling methods, capture of particles is determined by charge and so is not controlled by particle mass. We analyzed particle sizes captured from air, without regard to specific analyte by atomic force microscopy: particles at least as low as 100 nM could be captured from ambient air. This work introduces a very simple plug-and-play device that can sample air at a high-volume flow rate with no moving parts and collect particles down to the sub-micron range. In conclusion, the performance of the device is substantially equivalent to capture by pumping through a filter for microbiome analysis by quantitative PCR and amplicon sequencing.« less
A simple novel device for air sampling by electrokinetic capture
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gordon, Julian; Gandhi, Prasanthi; Shekhawat, Gajendra
A variety of different sampling devices are currently available to acquire air samples for the study of the microbiome of the air. All have a degree of technical complexity that limits deployment. Here, we evaluate the use of a novel device, which has no technical complexity and is easily deployable. An air-cleaning device powered by electrokinetic propulsion has been adapted to provide a universal method for collecting samples of the aerobiome. Plasma-induced charge in aerosol particles causes propulsion to and capture on a counter-electrode. The flow of ions creates net bulk airflow, with no moving parts. A device and electrodemore » assembly have been re-designed from air-cleaning technology to provide an average air flow of 120 lpm. This compares favorably with current air sampling devices based on physical air pumping. Capture efficiency was determined by comparison with a 0.4 μm polycarbonate reference filter, using fluorescent latex particles in a controlled environment chamber. Performance was compared with the same reference filter method in field studies in three different environments. For 23 common fungal species by quantitative polymerase chain reaction (qPCR), there was 100 % sensitivity and apparent specificity of 87%, with the reference filter taken as “gold standard.” Further, bacterial analysis of 16S RNA by amplicon sequencing showed equivalent community structure captured by the electrokinetic device and the reference filter. Unlike other current air sampling methods, capture of particles is determined by charge and so is not controlled by particle mass. We analyzed particle sizes captured from air, without regard to specific analyte by atomic force microscopy: particles at least as low as 100 nM could be captured from ambient air. This work introduces a very simple plug-and-play device that can sample air at a high-volume flow rate with no moving parts and collect particles down to the sub-micron range. In conclusion, the performance of the device is substantially equivalent to capture by pumping through a filter for microbiome analysis by quantitative PCR and amplicon sequencing.« less
A simple novel device for air sampling by electrokinetic capture.
Gordon, Julian; Gandhi, Prasanthi; Shekhawat, Gajendra; Frazier, Angel; Hampton-Marcell, Jarrad; Gilbert, Jack A
2015-12-27
A variety of different sampling devices are currently available to acquire air samples for the study of the microbiome of the air. All have a degree of technical complexity that limits deployment. Here, we evaluate the use of a novel device, which has no technical complexity and is easily deployable. An air-cleaning device powered by electrokinetic propulsion has been adapted to provide a universal method for collecting samples of the aerobiome. Plasma-induced charge in aerosol particles causes propulsion to and capture on a counter-electrode. The flow of ions creates net bulk airflow, with no moving parts. A device and electrode assembly have been re-designed from air-cleaning technology to provide an average air flow of 120 lpm. This compares favorably with current air sampling devices based on physical air pumping. Capture efficiency was determined by comparison with a 0.4 μm polycarbonate reference filter, using fluorescent latex particles in a controlled environment chamber. Performance was compared with the same reference filter method in field studies in three different environments. For 23 common fungal species by quantitative polymerase chain reaction (qPCR), there was 100 % sensitivity and apparent specificity of 87 %, with the reference filter taken as "gold standard." Further, bacterial analysis of 16S RNA by amplicon sequencing showed equivalent community structure captured by the electrokinetic device and the reference filter. Unlike other current air sampling methods, capture of particles is determined by charge and so is not controlled by particle mass. We analyzed particle sizes captured from air, without regard to specific analyte by atomic force microscopy: particles at least as low as 100 nM could be captured from ambient air. This work introduces a very simple plug-and-play device that can sample air at a high-volume flow rate with no moving parts and collect particles down to the sub-micron range. The performance of the device is substantially equivalent to capture by pumping through a filter for microbiome analysis by quantitative PCR and amplicon sequencing.
Biological monitoring of welders' exposure to chromium, molybdenum, tungsten and vanadium.
Ellingsen, Dag G; Chashchin, Maxim; Berlinger, Balazs; Fedorov, Vladimir; Chashchin, Valery; Thomassen, Yngvar
2017-05-01
Welders are exposed to a number of metallic elements during work. Bioaccessability, that is important for element uptake, has been little studied. This study addresses bioaccessability and uptake of chromium (Cr), molybdenum (Mo), tungsten (W) and vanadium (V) among welders. Bioaccessability of Cr, Mo, V and W was studied in airborne particulate matter collected by personal sampling of the workroom air among shipyard welders by using the lung lining fluid simulant Hatch solution. Associations between concentrations of Hatch soluble and non-soluble elements (Hatch sol and Hatch non-sol ) and concentrations of the four elements in whole blood, serum, blood cells and urine were studied. Air concentrations of the four elements were low. Only a small fraction of Cr, V and W was Hatch sol , while similar amounts of Mo were Hatch sol and Hatch non-sol . Welders (N=70) had statistically significantly higher concentrations of all four elements in urine and serum when compared to referents (N=74). Highly statistically significant associations were observed between urinary W and Hatch sol W (p<0.001) and serum V and Hatch sol V (p<0.001), in particular when air samples collected the day before collection of biological samples were considered. Associations between Hatch sol elements in air and their biological concentrations were higher than when Hatch non-sol concentrations were considered. Associations were generally higher when air samples collected the day before biological sampling were considered as compared to air samples collected two days before. Copyright © 2017 Elsevier GmbH. All rights reserved.
Transport of NMHCs and halocarbons observed by CARIBIC: A case study
NASA Astrophysics Data System (ADS)
Baker, A. K.; Brenninkmeijer, C. A. M.; Oram, D. E.; O'Sullivan, D. A.; Schuck, T. J.; Slemr, F.
2009-04-01
The CARIBIC project (Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container) involves the monthly deployment of an instrument container equipped to make atmospheric measurements from onboard a long-range commercial airliner. Since December 2004, flights for the second phase of CARIBIC have been aboard a Lufthansa Airbus A340-600 traveling between Frankfurt, Germany and destinations in Asia, North America and South America. The instrument package housed in the container is fully automated and during each flight carries out a variety of real-time trace gas and aerosol measurements, and also collects 28 air samples, which are analyzed upon return to the laboratory. Routine measurements made from the sampling flasks include greenhouse gases, nonmethane hydrocarbons (NMHCs), and halocarbons; results of air sample analysis form the basis for the data discussed here. While the majority of CARIBIC samples represent background free tropospheric air and air representative of the upper troposphere/lower stratosphere, the aircraft also, less frequently, encounters air parcels influenced by more recent emissions. Here we present a case study of a round-trip flight between Frankfurt and Toronto, Canada during September 2007. During this flight, different air masses of unique origin were encountered; a number of samples were influenced by transport from the Gulf of Mexico, while others had source regions in Central and Southeast Asia. Samples from the Gulf of Mexico exhibited enhancements in C3-C6 alkanes, as well as a number of halogenated compounds with oceanic sources, such as methyl iodide and bromoform, while Asian samples had enhanced levels of combustion products (CO, acetylene, benzene) and anthropogenic halocarbons (methlyene chloride, chloroform, perchloroethylene). Additionally, a number of samples also showed stratospheric influence, and these samples were characterized by relatively depleted levels of many of the compounds measured. Characterization of the different air masses will be discussed, and these results will be compared to samples collected during other CARIBIC flights, which are representative of both background air and air masses influenced by similar source regions.
EVALUATION OF THE FILTER PACK FOR LONG-DURATION SAMPLING OF AMBIENT AIR
A 14-week filter pack (FP) sampler evaluation field study was conducted at a site near Bondville, IL to investigate the impact of weekly sampling duration. Simultaneous samples were collected using collocated filter packs (FP) from two independent air quality monitoring networks...
This protocol describes how quality control samples should be handled in the field, and was designed as a quick reference source for the field staff. The protocol describes quality control samples for air-VOCs, air-particles, water samples, house dust, soil, urine, blood, hair, a...
Napoli, Christian; Marcotrigiano, Vincenzo; Montagna, Maria Teresa
2012-08-02
Since air can play a central role as a reservoir for microorganisms, in controlled environments such as operating theatres regular microbial monitoring is useful to measure air quality and identify critical situations. The aim of this study is to assess microbial contamination levels in operating theatres using both an active and a passive sampling method and then to assess if there is a correlation between the results of the two different sampling methods. The study was performed in 32 turbulent air flow operating theatres of a University Hospital in Southern Italy. Active sampling was carried out using the Surface Air System and passive sampling with settle plates, in accordance with ISO 14698. The Total Viable Count (TVC) was evaluated at rest (in the morning before the beginning of surgical activity) and in operational (during surgery). The mean TVC at rest was 12.4 CFU/m3 and 722.5 CFU/m2/h for active and passive samplings respectively. The mean in operational TVC was 93.8 CFU/m3 (SD = 52.69; range = 22-256) and 10496.5 CFU/m2/h (SD = 7460.5; range = 1415.5-25479.7) for active and passive samplings respectively. Statistical analysis confirmed that the two methods correlate in a comparable way with the quality of air. It is possible to conclude that both methods can be used for general monitoring of air contamination, such as routine surveillance programs. However, the choice must be made between one or the other to obtain specific information.
Legionnaires' Disease Bacteria in power plant cooling systems: downtime report. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tyndall, R.L.; Solomon, J.A.; Christensen, S.W.
1985-04-01
Legionnaires' Disease Bacteria (Legionella) are a normal part of the aquatic community that, when aerosolized, can be pathogenic to man. The downtime study was designed to determine the degree to which Legionella populations are aerosolized during cleaning and maintenance operations in a closed-cycle steam-electric power plant. Both high-volume and impinger air samples were collected prior to and during downtime operations. Emphasis was placed on sampling inside or adjacent to water boxes, condensers, and cooling towers. Control air samples were taken upwind from the plant site. Water and sludge samples were also collected at various locations. In the laboratory, the concentrationsmore » of Groups A, B, and C Legionella were determined using the direct fluorescent antibody method. All positive air samples, and other selected air samples, were injected into guinea pigs to detect infectious Legionella. Legionella could be detected in only 12 of the 126 air samples collected. These were predominantly Group A Legionella (L. pneumophila, serogroups 1 to 6). All 12 positive samples had been collected in the vicinity of water boxes, condensers, detention ponds, and cooling towers during downtime operations where aerosolization of Legionella populations would be expected. None of the air samples yielded infectious Legionella when injected into guinea pigs. Detection of Legionella in air samples taken during downtime was significantly more likely than detection during normal operating conditions (p <0.01). 13 refs., 4 figs., 10 tabs.« less
Effect of different drying methods on moisture ratio and rehydration of pumpkin slices.
Seremet Ceclu, Liliana; Botez, Elisabeta; Nistor, Oana-Viorela; Andronoiu, Doina Georgeta; Mocanu, Gabriel-Danut
2016-03-15
This study was carried to determine the influence of hot air drying process and combined methods on physicochemical properties of pumpkin (Cucurbita moschata) samples. The experiments in hot air chamber were lead at 50, 60 and 70 °C. The combined method consists of a triple combination of the main drying techniques. Thus, in first stage the samples were dried in hot air convection at 60 °C followed by hot air ventilation at 40 °C simultaneous with microwave. The time required to reduce the moisture content to any given level was highly dependent on the drying conditions. So, the highest value of drying time in hot air has been 540 min at 50 °C, while the lowest time has been 189 min in hot air combined by microwave at 40 °C and a power of 315 W. The samples dried by hot air shows a higher rehydration capacity than samples dried by combined method. Copyright © 2015 Elsevier Ltd. All rights reserved.
Variability of indoor fungal microbiome of green and non-green low-income homes in Cincinnati, Ohio.
Coombs, Kanistha; Taft, Diana; Ward, Doyle V; Green, Brett J; Chew, Ginger L; Shamsaei, Behrouz; Meller, Jaroslaw; Indugula, Reshmi; Reponen, Tiina
2018-01-01
"Green" housing is designed to use low-impact materials, increase energy efficiency and improve occupant health. However, little is known about the indoor mycobiome of green homes. The current study is a subset of a multicenter study that aims to investigate the indoor environment of green homes and the respiratory health of asthmatic children. In the current study, the mycobiome in air, bed dust and floor dust was compared between green (study site) and non-green (control site), low-income homes in Cincinnati, Ohio. The samples were collected at baseline (within four months following renovation), and 12months after the baseline at the study site. Parallel sample collection was conducted in non-green control homes. Air samples were collected by PM2.5 samplers over 5-days. Bed and floor dust samples were vacuumed after the air sampling was completed. The DNA sample extracts were analyzed using ITS amplicon sequencing. Analysis indicated that there was no clear trend in the fungal communities between green and non-green homes. Instead, fungal community differences were greatest between sample types - air, bed, and floor. Microbial communities also changed substantially between sampling intervals in both green and non-green homes for all sample types, potentially indicating that there was very little stability in the mycobiomes. Research gaps remain regarding how indoor mycobiome fluctuates over time. Longer follow-up periods might elucidate the effect of green renovation on microbial load in buildings. Copyright © 2017 Elsevier B.V. All rights reserved.
Improved Sampling Method Reduces Isokinetic Sampling Errors.
ERIC Educational Resources Information Center
Karels, Gale G.
The particulate sampling system currently in use by the Bay Area Air Pollution Control District, San Francisco, California is described in this presentation for the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971. The method represents a practical, inexpensive tool that can…
Air-conditioning vs. presence of pathogenic fungi in hospital operating theatre environment.
Gniadek, Agnieszka; Macura, Anna B
2011-01-01
Infections related to modern surgical procedures present a difficult problem for contemporary medicine. Infections acquired during surgery represent a risk factor related to therapeutical interventions. Eradication of microorganisms from hospital operating theatre environment may contribute to reduction of infections as the laminar flow air-conditioning considerably reduces the number of microorganisms in the hospital environment. The objective of the study was to evaluate the occurrence of fungi in air-conditioned operating theatre rooms. The study was carried out in one of the hospitals in Krak6w during December 2009. Indoor air samples and imprints from the walls were collected from five operating theatre rooms. A total of fifty indoor air samples were collected with a MAS-100 device, and twenty five imprints from the walls were collected using a Count Tact method. Fungal growth was observed in 48 air samples; the average numbers of fungi were within the range of 5-100 c.f.u. in one cubic metre of the air. Fungi were detected only in four samples of the wall imprints; the number of fungi was 0.01 c.f.u. per one square centimetre of the surface. The mould genus Aspergillus was most frequently isolated, and the species A. fumigatus and A. versicolor were the dominating ones. To ensure microbiological cleanness of hospital operating theatre, the air-conditioning system should be properly maintained. Domination of the Aspergillus fungi in indoor air as well as increase in the number of moulds in the samples taken in evenings (p < 0.05) may suggest that the room decontamination procedures were neglected.
Khan, Muhammad Usman; Besis, Athanasios; Li, Jun; Zhang, Gan; Malik, Riffat Naseem
2017-10-01
Data regarding flame retardants (FRs) in indoor and outdoor air and their exposure to population are scarce and especially unknown in the case of Pakistan. The current study was designed to probe FR concentrations and distribution pattern in indoor and outdoor air at different altitudinal zones (DAZs) of Pakistan with special emphasis on their risk to the exposed population. In this study, passive air samplers for the purpose of FR deposition were deployed in indoor and outdoor air at the industrial, rural, and background/colder zones/sites. All the indoor and outdoor air samples collected from DAZs were analyzed for the target FRs (9.30-472.30 pg/m 3 ), showing a decreasing trend as follows: ∑NBFRs > ∑PBDEs > ∑DP. However, significant correlations among FRs in the indoor and outdoor air at DAZs signified a similar source of FR origin that is used in different consumer goods. Furthermore, air mass trajectories revealed that movement of air over industrial area sources influenced concentrations of FRs at rural sites. The FR concentrations, estimated daily intake (EDI) and the hazard quotient (HQ), were recorded to be higher in toddlers than those in adults. In addition, indoor air samples showed higher FR levels, EDI and HQ, than outdoor air samples. An elevated FR concentrations and their prevalent exposure risks were recorded in the industrial zones followed by rural and background zones. The HQ for BDE-47 and BDE-99 in the indoor and outdoor air samples at different industrial and rural sites were recorded to be >1 in toddlers and adults, this further warrants a health risk in the population. However, FR investigation in indoor and outdoor air samples will provide a baseline data in Pakistan to take further steps by the government and agencies for its implementations. Copyright © 2017 Elsevier Ltd. All rights reserved.
Investigation of Air Quality Problems in an Indoor Swimming Pool: A Case Study.
Lévesque, Benoit; Vézina, Lorraine; Gauvin, Denis; Leroux, Patrice
2015-10-01
Trichloramine (NCl3) is the contaminant suspected the most to cause irritative respiratory symptoms among swimmers and swimming pool workers. Following complaints by employees working in an indoor swimming pool, this study set out to identify the determinants of NCl3 air concentrations in that particular swimming pool. To document NCl3 air levels, air samples (n = 26) were collected once or twice a day for 3 h, at least 3 days per week, between October and December 2011. Water samples were taken three times during air sampling to verify free chlorine, chloramines, alkalinity, conductivity, pH, water temperature, and turbidity. Water changes were also recorded, along with the number of bathers. Ventilation (outdoor air flow) was modified to verify the influence of this important variable. Data were evaluated by analysis of variance. Mean NCl3 air concentration was 0.38 mg m(-3). The best model explaining variations of NCl3 air levels (r2 = 0.83) included sampling period (P = 0.002, NCl3 was higher in the evening versus the morning), water changes (P = 0.02, NCl3 was lower with water changes between 60 and 90 min day(-1) versus <60 min day(-1)), and ventilation (P = 0.0002, NCl3 was lower with ≥2 air changes per hour (ACH) versus <1 ACH). Although based on only 26 air samples, our results indicate that ventilation is an important determinant of NCl3 air concentration in swimming pool air. There is limited information available on the air quality of indoor swimming pools and the relationship with ventilation. Efforts are needed to document the situation and to develop state-of-the-art facilities for ventilation of indoor swimming pools. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
Alamdar, Ambreen; Syed, Jabir Hussain; Malik, Riffat Naseem; Katsoyiannis, Athanasios; Liu, Junwen; Li, Jun; Zhang, Gan; Jones, Kevin C
2014-02-01
This study was conducted to examine organochlorine pesticides (OCPs) contamination levels in the surface soil and air samples together with air-soil exchange fluxes at an obsolete pesticide dumping ground and the associated areas from Hyderabad City, Pakistan. Among all the sampling sites, concentrations of OCPs in the soil and air samples were found highest in obsolete pesticide dumping ground, whereas dominant contaminants were dichlorodiphenyltrichloroethane (DDTs) (soil: 77-212,200 ng g(-1); air: 90,700 pg m(-3)) and hexachlorocyclohexane (HCHs) (soil: 43-4,090 ng g(-1); air: 97,400 pg m(-3)) followed by chlordane, heptachlor and hexachlorobenzene (HCB). OCPs diagnostic indicative ratios reflect historical use as well as fresh input in the study area. Moreover, the air and soil fugacity ratios (0.9-1.0) at the dumping ground reflecting a tendency towards net volatilization of OCPs, while at the other sampling sites, the fugacity ratios indicate in some cases deposition and in other cases volatilization. Elevated concentrations of DDTs and HCHs at pesticide dumping ground and its surroundings pose potential exposure risk to biological organisms, to the safety of agricultural products and to the human health. Our study thus emphasizes the need of spatio-temporal monitoring of OCPs at local and regional scale to assess and remediate the future adverse implications. © 2013.
Korves, T M; Piceno, Y M; Tom, L M; Desantis, T Z; Jones, B W; Andersen, G L; Hwang, G M
2013-02-01
Air travel can rapidly transport infectious diseases globally. To facilitate the design of biosensors for infectious organisms in commercial aircraft, we characterized bacterial diversity in aircraft air. Samples from 61 aircraft high-efficiency particulate air (HEPA) filters were analyzed with a custom microarray of 16S rRNA gene sequences (PhyloChip), representing bacterial lineages. A total of 606 subfamilies from 41 phyla were detected. The most abundant bacterial subfamilies included bacteria associated with humans, especially skin, gastrointestinal and respiratory tracts, and with water and soil habitats. Operational taxonomic units that contain important human pathogens as well as their close, more benign relatives were detected. When compared to 43 samples of urban outdoor air, aircraft samples differed in composition, with higher relative abundance of Firmicutes and Gammaproteobacteria lineages in aircraft samples, and higher relative abundance of Actinobacteria and Betaproteobacteria lineages in outdoor air samples. In addition, aircraft and outdoor air samples differed in the incidence of taxa containing human pathogens. Overall, these results demonstrate that HEPA filter samples can be used to deeply characterize bacterial diversity in aircraft air and suggest that the presence of close relatives of certain pathogens must be taken into account in probe design for aircraft biosensors. A biosensor that could be deployed in commercial aircraft would be required to function at an extremely low false alarm rate, making an understanding of microbial background important. This study reveals a diverse bacterial background present on aircraft, including bacteria closely related to pathogens of public health concern. Furthermore, this aircraft background is different from outdoor air, suggesting different probes may be needed to detect airborne contaminants to achieve minimal false alarm rates. This study also indicates that aircraft HEPA filters could be used with other molecular techniques to further characterize background bacteria and in investigations in the wake of a disease outbreak. © 2012 John Wiley & Sons A/S.
Davis, Meghan F; Pisanic, Nora; Rhodes, Sarah M; Brown, Alexis; Keller, Haley; Nadimpalli, Maya; Christ, Andrea; Ludwig, Shanna; Ordak, Carly; Spicer, Kristoffer; Love, David C; Larsen, Jesper; Wright, Asher; Blacklin, Sarah; Flowers, Billy; Stewart, Jill; Sexton, Kenneth G; Rule, Ana M; Heaney, Christopher D
2018-05-01
Occupational exposure to swine has been associated with increased Staphylococcus aureus carriage, including antimicrobial-resistant strains, and increased risk of infections. To characterize animal and environmental routes of worker exposure, we optimized methods to identify S. aureus on operations that raise swine in confinement with antibiotics (industrial hog operation: IHO) versus on pasture without antibiotics (antibiotic-free hog operation: AFHO). We associated findings from tested swine and environmental samples with those from personal inhalable air samplers on worker surrogates at one IHO and three AFHOs in North Carolina using a new One Health approach. We determined swine S. aureus carriage status by collecting swab samples from multiple anatomical sites, and we determined environmental positivity for airborne bioaerosols with inhalable and impinger samplers and a single-stage impactor (ambient air) cross-sectionally. All samples were analyzed for S. aureus, and isolates were tested for antimicrobial susceptibility, absence of scn (livestock marker), and spa type. Seventeen of twenty (85%) swine sampled at the one IHO carried S. aureus at >1 anatomical sites compared to none of 30 (0%) swine sampled at the three AFHOs. All S. aureus isolates recovered from IHO swine and air samples were scn negative and spa type t337; almost all isolates (62/63) were multidrug resistant. S. aureus was recovered from eight of 14 (67%) ambient air and two (100%) worker surrogate personal air samples at the one IHO, whereas no S. aureus isolates were recovered from 19 ambient and six personal air samples at the three AFHOs. Personal worker surrogate inhalable sample findings were consistent with both swine and ambient air data, indicating the potential for workplace exposure. IHO swine and the one IHO environment could be a source of potential pathogen exposure to workers, as supported by the detection of multidrug-resistant S. aureus (MDRSA) with livestock-associated spa type t337 among swine, worker surrogate personal air samplers and environmental air samples at the one IHO but none of the three AFHOs sampled in this study. Concurrent sampling of swine, personal swine worker surrogate air, and ambient airborne dust demonstrated that IHO workers may be exposed through both direct (animal contact) and indirect (airborne) routes of transmission. Investigation of the effectiveness of contact and respiratory protections is warranted to prevent IHO worker exposure to multidrug-resistant livestock-associated S. aureus and other pathogens. Copyright © 2017 Elsevier Inc. All rights reserved.
The purpose of this SOP is to describe the procedures for extracting and preparing an air sample consisting of a polyurethane foam (PUF) plug and Teflon-coated glass fiber filter (Pallflex T60A20) for analysis of pesticides. This procedure covers sample preparation for samples t...
Analytical results obtained by thermal desorption GC/MS for 24h diffusive sampling of 11 volatile organic compounds (VOCs) are compared with results of time-averaged active sampling at a known constant flow rate. Air samples were collected with co-located duplicate diffusive samp...
Design and validation of a wind tunnel system for odour sampling on liquid area sources.
Capelli, L; Sironi, S; Del Rosso, R; Céntola, P
2009-01-01
The aim of this study is to describe the methods adopted for the design and the experimental validation of a wind tunnel, a sampling system suitable for the collection of gaseous samples on passive area sources, which allows to simulate wind action on the surface to be monitored. The first step of the work was the study of the air velocity profiles. The second step of the work consisted in the validation of the sampling system. For this purpose, the odour concentration of some air samples collected by means of the wind tunnel was measured by dynamic olfactometry. The results of the air velocity measurements show that the wind tunnel design features enabled the achievement of a uniform and homogeneous air flow through the hood. Moreover, the laboratory tests showed a very good correspondence between the odour concentration values measured at the wind tunnel outlet and the odour concentration values predicted by the application of a specific volatilization model, based on the Prandtl boundary layer theory. The agreement between experimental and theoretical trends demonstrate that the studied wind tunnel represents a suitable sampling system for the simulation of specific odour emission rates from liquid area sources without outward flow.
The relationships between air exposure, negative pressure, and hemolysis.
Pohlmann, Joshua R; Toomasian, John M; Hampton, Claire E; Cook, Keith E; Annich, Gail M; Bartlett, Robert H
2009-01-01
The purpose of this study was to describe the hemolytic effects of both negative pressure and an air-blood interface independently and in combination in an in vitro static blood model. Samples of fresh ovine or human blood (5 ml) were subjected to a bubbling air interface (0-100 ml/min) or negative pressure (0-600 mm Hg) separately, or in combination, for controlled periods of time and analyzed for hemolysis. Neither negative pressure nor an air interface alone increased hemolysis. However, when air and negative pressure were combined, hemolysis increased as a function of negative pressure, the air interface, and time. Moreover, when blood samples were exposed to air before initiating the test, hemolysis was four to five times greater than samples not preexposed to air. When these experiments were repeated using freshly drawn human blood, the same phenomena were observed, but the hemolysis was significantly higher than that observed in sheep blood. In this model, hemolysis is caused by combined air and negative pressure and is unrelated to either factor alone.
Singh, Ajit Pratap; Chakrabarti, Sumanta; Kumar, Sumit; Singh, Anjaney
2017-08-01
This paper deals with assessment of air quality in Haora River basin using two techniques. Initially, air quality indices were evaluated using a modified EPA method. The indices were also evaluated using a fuzzy comprehensive assessment (FCA) method. The results obtained from the fuzzy comprehensive assessment method were compared to that obtained from the modified EPA method. To illustrate the applicability of the methodology proposed herein, a case study has been presented. Air samples have been collected at 10 sampling sites located along Haora River. Six important air pollutants, namely, carbon monoxide, sulfur dioxide, nitrogen dioxide, suspended particulate matter (SPM), PM 10 , and lead, were monitored continuously, and air quality maps were generated on the GIS platform. Comparison of the methodologies has clearly highlighted superiority and robustness of the fuzzy comprehensive assessment method in determining air quality indices under study. It has effectively addressed the inherent uncertainties involved in the evaluation, modeling, and interpretation of sampling data, which was beyond the scope of the traditional weighted approaches employed otherwise. The FCA method is robust and prepares a credible platform of air quality evaluation and identification, in face of the uncertainties that remain eclipsed in the traditional approaches like the modified EPA method. The insights gained through the present study are believed to be of pivotal significance in guiding the development and implementation of effective environmental remedial action plans in the study area.
Legionnaires' disease bacteria in power plant cooling systems: downtime report. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tyndall, R.L.; Solomon, J.A.; Christensen, S.W.
1985-11-01
Legionnaires' disease bacteria (Legionella) are a normal part of the aquatic community that, when aerosolized, can be pathogenic to man. The downtime study was designed to determine the degree to which Legionella populations are aerosolized during cleaning and maintenance operations in a closed-cycle steam-electric power plant. Both high-volume and impinger air samples were collected prior to and during downtime operations. Emphasis was placed on sampling inside or adjacent to water boxes, condensers, and cooling towers. Control air samples were taken upwind from the plant site. Water and sludge samples were also collected at various locations. In the laboratory, the concentrationsmore » of Legionella were determined using the direct fluorescent antibody method. All positive air samples, and other selected air samples, were injected into guinea pigs to detect infectious Legionella. Legionella could be detected in only 12 of the 127 air samples collected. These were predominantly L. pneumophila, serogroups 1-6. In contrast to the air samples, most of the water and sludge samples were positive for Legionella, again predominantly L. pneumophila, serogroups 1-6. The highest Legionella concentrations were found in sludge samples associated with condenser tube cleaning. Among the water samples, the highest Legionella concentrations were found in cooling towers, immediately after the tower basins were cleaned and refilled, and in condenser tubes. Two of the three cooling tower water samples collected prior to downtime operations were infectious for guinea pigs. 16 refs., 4 figs., 11 tabs.« less
Gibbs, Jenna L; Yost, Michael G; Negrete, Maria; Fenske, Richard A
2017-03-01
Recent studies have highlighted the increased potency of oxygen analogs of organophosphorus pesticides. These pesticides and oxygen analogs have previously been identified in the atmosphere following spray applications in the states of California and Washington. We used two passive sampling methods to measure levels of the ollowing organophosphorus pesticides: chlorpyrifos, azinphos-methyl, and their oxygen analogs at 14 farmworker and 9 non-farmworker households in an agricultural region of central Washington State in 2011. The passive methods included polyurethane foam passive air samplers deployed outdoors and indoors and polypropylene deposition plates deployed indoors. We collected cumulative monthly samples during the pesticide application seasons and during the winter season as a control. Monthly outdoor air concentrations ranged from 9.2 to 199 ng/m 3 for chlorpyrifos, 0.03 to 20 ng/m 3 for chlorpyrifos-oxon, < LOD (limit of detection) to 7.3 ng/m 3 for azinphos-methyl, and < LOD to 0.8 ng/m 3 for azinphos-methyl-oxon. Samples from proximal households (≤ 250 m) had significantly higher outdoor air concentrations of chlorpyrifos, chlorpyrifos-oxon, and azinphos-methyl than did samples from nonproximal households ( p ≤ 0.02). Overall, indoor air concentrations were lower than outdoors. For example, all outdoor air samples for chlorpyrifos and 97% of samples for azinphos-methyl were > LOD. Indoors, only 78% of air samples for chlorpyrifos and 35% of samples for azinphos-methyl were > LOD. Samples from farmworker households had higher indoor air concentrations of both pesticides than did samples from non-farmworker households. Mean indoor and outdoor air concentration ratios for chlorpyrifos and azinphos-methyl were 0.17 and 0.44, respectively. We identified higher levels in air and on surfaces at both proximal and farmworker households. Our findings further confirm the presence of pesticides and their oxygen analogs in air and highlight their potential for infiltration of indoor living environments. Citation: Gibbs JL, Yost MG, Negrete M, Fenske RA. 2017. Passive sampling for indoor and outdoor exposures to chlorpyrifos, azinphos-methyl, and oxygen analogs in a rural agricultural community. Environ Health Perspect 125:333-341; http://dx.doi.org/10.1289/EHP425.
Comparison of stationary and personal air sampling with an ...
Manganese (Mn) is ubiquitous in the environment and essential for normal growth and development, yet excessive exposure can lead to impairments in neurological function. This study modeled ambient Mn concentrations as an alternative to stationary and personal air sampling to assess exposure for children enrolled in the Communities Actively Researching Exposure Study in Marietta, OH. Ambient air Mn concentration values were modeled using US Environmental Protection Agency’s Air Dispersion Model AERMOD based on emissions from the ferromanganese refinery located in Marietta. Modeled Mn concentrations were compared with Mn concentrations from a nearby stationary air monitor. The Index of Agreement for modeled versus monitored data was 0.34 (48 h levels) and 0.79 (monthly levels). Fractional bias was 0.026 for 48 h levels and −0.019 for monthly levels. The ratio of modeled ambient air Mn to measured ambient air Mn at the annual time scale was 0.94. Modeled values were also time matched to personal air samples for 19 children. The modeled values explained a greater degree of variability in personal exposures compared with time-weighted distance from the emission source. Based on these results modeled Mn concentrations provided a suitable approach for assessing airborne Mn exposure in this cohort. The purpose of the study was to investigate the use of air-dispersion modeling as an approach to exposure assessment for ambient manganese.
AirCore-HR: a high-resolution column sampling to enhance the vertical description of CH4 and CO2
NASA Astrophysics Data System (ADS)
Membrive, Olivier; Crevoisier, Cyril; Sweeney, Colm; Danis, François; Hertzog, Albert; Engel, Andreas; Bönisch, Harald; Picon, Laurence
2017-06-01
An original and innovative sampling system called AirCore was presented by NOAA in 2010 Karion et al.(2010). It consists of a long ( > 100 m) and narrow ( < 1 cm) stainless steel tube that can retain a profile of atmospheric air. The captured air sample has then to be analyzed with a gas analyzer for trace mole fraction. In this study, we introduce a new AirCore aiming to improve resolution along the vertical with the objectives to (i) better capture the vertical distribution of CO2 and CH4, (ii) provide a tool to compare AirCores and validate the estimated vertical resolution achieved by AirCores. This (high-resolution) AirCore-HR consists of a 300 m tube, combining 200 m of 0.125 in. (3.175 mm) tube and a 100 m of 0.25 in. (6.35 mm) tube. This new configuration allows us to achieve a vertical resolution of 300 m up to 15 km and better than 500 m up to 22 km (if analysis of the retained sample is performed within 3 h). The AirCore-HR was flown for the first time during the annual StratoScience campaign from CNES in August 2014 from Timmins (Ontario, Canada). High-resolution vertical profiles of CO2 and CH4 up to 25 km were successfully retrieved. These profiles revealed well-defined transport structures in the troposphere (also seen in CAMS-ECMWF high-resolution forecasts of CO2 and CH4 profiles) and captured the decrease of CO2 and CH4 in the stratosphere. The multi-instrument gondola also carried two other low-resolution AirCore-GUF that allowed us to perform direct comparisons and study the underlying processing method used to convert the sample of air to greenhouse gases vertical profiles. In particular, degrading the AirCore-HR derived profiles to the low resolution of AirCore-GUF yields an excellent match between both sets of CH4 profiles and shows a good consistency in terms of vertical structures. This fully validates the theoretical vertical resolution achievable by AirCores. Concerning CO2 although a good agreement is found in terms of vertical structure, the comparison between the various AirCores yields a large and variable bias (up to almost 3 ppm in some parts of the profiles). The reasons of this bias, possibly related to the drying agent used to dry the air, are still being investigated. Finally, the uncertainties associated with the measurements are assessed, yielding an average uncertainty below 3 ppb for CH4 and 0.25 ppm for CO2 with the major source of uncertainty coming from the potential loss of air sample on the ground and the choice of the starting and ending point of the collected air sample inside the tube. In an ideal case where the sample would be fully retained, it would be possible to know precisely the pressure at which air was sampled last and thus to improve the overall uncertainty to about 0.1 ppm for CO2 and 2 ppb for CH4.
Cleary, Erika; Asher, Mary; Olawoyin, Richard; Zhang, Kuangyuan
2017-11-01
Ambient air pollution is a public health issue which could potentially exacerbate pre-existing respiratory conditions and contribute to increases in asthma incidence. This study aims to address gaps in understanding how IAQ is impacted by outdoor air quality, which was done by sampling for indoor gaseous and particulate pollutants in residence and facilities near the sources of pollution. The study areas were selected due to non-attainment status with air quality standards, as well as demographic and socioeconomic status of those residing in these areas. Samples are obtained from five locations around the study areas. The sampling procedure involves active sampling methodologies for particulate matter (PM) and gases. Average volatile organic compounds (VOC) levels of 2.71 ppm were measured at a location, while the average particulate matter (PM) concentrations in three study locations were; 15,979 pt/cc, 9533 pt/cc, 5267 pt/cc respectively, which exceeded clean background environment level of 500-2000 pt/cc. All locations had average CO concentrations above 0.3 ppm, which is potentially associated with elevated asthma symptoms. Results demonstrated that facilities in the study area have increased levels of indoor air pollutants that potentially increase asthma and respiratory issues. The study concludes that particulate and gaseous pollutant levels in the study areas are a concerning human health issue. The study outcomes have significant implications for air quality exposure modeling and potential exposure mitigation strategies, which are expected to facilitate the implementation of public policies for improved human health conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.
2012-01-01
Background Since air can play a central role as a reservoir for microorganisms, in controlled environments such as operating theatres regular microbial monitoring is useful to measure air quality and identify critical situations. The aim of this study is to assess microbial contamination levels in operating theatres using both an active and a passive sampling method and then to assess if there is a correlation between the results of the two different sampling methods. Methods The study was performed in 32 turbulent air flow operating theatres of a University Hospital in Southern Italy. Active sampling was carried out using the Surface Air System and passive sampling with settle plates, in accordance with ISO 14698. The Total Viable Count (TVC) was evaluated at rest (in the morning before the beginning of surgical activity) and in operational (during surgery). Results The mean TVC at rest was 12.4 CFU/m3 and 722.5 CFU/m2/h for active and passive samplings respectively. The mean in operational TVC was 93.8 CFU/m3 (SD = 52.69; range = 22-256) and 10496.5 CFU/m2/h (SD = 7460.5; range = 1415.5-25479.7) for active and passive samplings respectively. Statistical analysis confirmed that the two methods correlate in a comparable way with the quality of air. Conclusion It is possible to conclude that both methods can be used for general monitoring of air contamination, such as routine surveillance programs. However, the choice must be made between one or the other to obtain specific information. PMID:22853006
Cox, Jennie; Indugula, Reshmi; Vesper, Stephen; Zhu, Zheng; Jandarov, Roman; Reponen, Tiina
2017-10-18
Evaluating fungal contamination indoors is complicated because of the many different sampling methods utilized. In this study, fungal contamination was evaluated using five sampling methods and four matrices for results. The five sampling methods were a 48 hour indoor air sample collected with a Button™ inhalable aerosol sampler and four types of dust samples: a vacuumed floor dust sample, newly settled dust collected for four weeks onto two types of electrostatic dust cloths (EDCs) in trays, and a wipe sample of dust from above floor surfaces. The samples were obtained in the bedrooms of asthmatic children (n = 14). Quantitative polymerase chain reaction (qPCR) was used to analyze the dust and air samples for the 36 fungal species that make up the Environmental Relative Moldiness Index (ERMI). The results from the samples were compared by four matrices: total concentration of fungal cells, concentration of fungal species associated with indoor environments, concentration of fungal species associated with outdoor environments, and ERMI values (or ERMI-like values for air samples). The ERMI values for the dust samples and the ERMI-like values for the 48 hour air samples were not significantly different. The total cell concentrations of the 36 species obtained with the four dust collection methods correlated significantly (r = 0.64-0.79, p < 0.05), with the exception of the vacuumed floor dust and newly settled dust. In addition, fungal cell concentrations of indoor associated species correlated well between all four dust sampling methods (r = 0.68-0.86, p < 0.01). No correlation was found between the fungal concentrations in the air and dust samples primarily because of differences in concentrations of Cladosporium cladosporioides Type 1 and Epicoccum nigrum. A representative type of dust sample and a 48 hour air sample might both provide useful information about fungal exposures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wallace, L.A.; Pellizzari, E.; Hartwell, T.
A pilot study to test methods of estimating personal exposures to toxic substances and corresponding body burdens was carried out between July and December 1980. Individual exposures to about a dozen volatile organic compounds in air and drinking water were measured for volunteers in New Jersey and North Carolina. Breath samples were also collected from all subjects. About 230 personal air samples, 170 drinking water samples, 66 breath samples, and 4 food samples (16 composites) were analyzed for the target chemicals. Ten compounds were present in air and eight were transmitted mainly through that medium. Chloroform and bromodichloromethane were predominantlymore » transmitted through water and beverages. Food appeared to be a miner route of exposure, except possibly for trichloroethylene in margarine. Seven compounds were present in more than half of the breath samples. Diurnal and seasonal variations were noted in air and water concentrations of some compounds. Some, but not all, of the potentially occupationally exposed individuals had significantly higher workplace exposures to several chemicals. Distributions of air exposures were closer to log normal than normal for most chemicals. Several chemicals were highly correlated with each other in personal air samples, indicating possible common sources of exposures. Compounds detected included benzene, chlorinated aromatic hydrocarbons, chlorinated aliphatic hydrocarbons, halogens and vinyl chloride.« less
Applicability of canisters for sample storage in the determination of hazardous air pollutants
NASA Astrophysics Data System (ADS)
Kelly, Thomas J.; Holdren, Michael W.
This paper evaluates the applicability of canisters for storage of air samples containing volatile organic compounds listed among the 189 hazardous air pollutants (HAPs) in the 1990 U.S. Clean Air Act Amendments. Nearly 100 HAPs have sufficient vapor pressure to be considered volatile compounds. Of those volatile organic HAPs, 52 have been tested previously for stability during storage in canisters. The published HAP stability studies are reviewed, illustrating that for most of the 52 HAPs tested, canisters are an effective sample storage approach. However, the published stability studies used a variety of canister types and test procedures, and generally considered only a few compounds in a very small set of canisters. A comparison of chemical and physical properties of the HAPs has also been conducted, to evaluate the applicability of canister sampling for other HAPs, for which canister stability testing has never been conducted. Of 45 volatile HAPs never tested in canisters, this comparison identifies nine for which canisters should be effective, and 17 for which canisters are not likely to be effective. For the other 19 HAPs, no clear decision can be reached on the likely applicability of air sample storage in canisters.
Quantitative filter forensics for indoor particle sampling.
Haaland, D; Siegel, J A
2017-03-01
Filter forensics is a promising indoor air investigation technique involving the analysis of dust which has collected on filters in central forced-air heating, ventilation, and air conditioning (HVAC) or portable systems to determine the presence of indoor particle-bound contaminants. In this study, we summarize past filter forensics research to explore what it reveals about the sampling technique and the indoor environment. There are 60 investigations in the literature that have used this sampling technique for a variety of biotic and abiotic contaminants. Many studies identified differences between contaminant concentrations in different buildings using this technique. Based on this literature review, we identified a lack of quantification as a gap in the past literature. Accordingly, we propose an approach to quantitatively link contaminants extracted from HVAC filter dust to time-averaged integrated air concentrations. This quantitative filter forensics approach has great potential to measure indoor air concentrations of a wide variety of particle-bound contaminants. Future studies directly comparing quantitative filter forensics to alternative sampling techniques are required to fully assess this approach, but analysis of past research suggests the enormous possibility of this approach. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
ATMOSPHERIC VOLATILE ORGANIC COMPOUND MEASUREMENTS DURING THE 1996 PASO DEL NORTE OZONE STUDY
Ambient air VOC samples were collected at surface air quality monitoring sites, near sources of interest, and aloft on the US (El Paso) and Mexican (Ciudad Juarez) side of the border during a six-week period of the 1996 Paso del Norte Ozone Study. Samples were collected at five...
SAMPLE DESIGN CONSIDERATIONS FOR INDOOR AIR EXPOSURE SURVEYS
Recent studies have shown that the traditional practice of monitoring outdoor (ambient) air quality leads to little information regarding the exposures of people in indoor surroundings. Consequently, EPA has begun a series of studies to determine the air pollution exposures peopl...
Shimose, Luis A; Masuda, Eriko; Sfeir, Maroun; Berbel Caban, Ana; Bueno, Maria X; dePascale, Dennise; Spychala, Caressa N; Cleary, Timothy; Namias, Nicholas; Kett, Daniel H; Doi, Yohei; Munoz-Price, L Silvia
2016-07-01
OBJECTIVE To concomitantly determine the differential degrees of air and environmental contamination by Acinetobacter baumannii based on anatomic source of colonization and type of ICU layout (single-occupancy vs open layout). DESIGN Longitudinal prospective surveillance study of air and environmental surfaces in patient rooms. SETTING A 1,500-bed public teaching hospital in Miami, Florida. PATIENTS Consecutive A. baumannii-colonized patients admitted to our ICUs between October 2013 and February 2014. METHODS Air and environmental surfaces of the rooms of A. baumannii-colonized patients were sampled daily for up to 10 days. Pulsed-field gel electrophoresis (PFGE) was used to type and match the matching air, environmental, and clinical A. baumannii isolates. RESULTS A total of 25 A. baumannii-colonized patients were identified during the study period; 17 were colonized in the respiratory tract and 8 were colonized in the rectum. In rooms with rectally colonized patients, 38.3% of air samples were positive for A. baumannii; in rooms of patients with respiratory colonization, 13.1% of air samples were positive (P=.0001). In rooms with rectally colonized patients, 15.5% of environmental samples were positive for A. baumannii; in rooms of patients with respiratory colonization, 9.5% of environmental samples were positive (P=.02). The rates of air contamination in the open-layout and single-occupancy ICUs were 17.9% and 21.8%, respectively (P=.5). Environmental surfaces were positive in 9.5% of instances in open-layout ICUs versus 13.4% in single-occupancy ICUs (P=.09). CONCLUSIONS Air and environmental surface contaminations were significantly greater among rectally colonized patients; however, ICU layout did not influence the rate of contamination. Infect Control Hosp Epidemiol 2016;37:777-781.
Low concentrations of persistent organic pollutants (POPs) in air at Cape Verde.
Nøst, Therese Haugdahl; Halse, Anne Karine; Schlabach, Martin; Bäcklund, Are; Eckhardt, Sabine; Breivik, Knut
2018-01-15
Ambient air is a core medium for monitoring of persistent organic pollutants (POPs) under the Stockholm Convention and is used in studies of global transports of POPs and their atmospheric sources and source regions. Still, data based on active air sampling remain scarce in many regions. The primary objectives of this study were to (i) monitor concentrations of selected POPs in air outside West Africa, and (ii) to evaluate potential atmospheric processes and source regions affecting measured concentrations. For this purpose, an active high-volume air sampler was installed on the Cape Verde Atmospheric Observatory at Cape Verde outside the coast of West Africa. Sampling commenced in May 2012 and 43 samples (24h sampling) were collected until June 2013. The samples were analyzed for selected polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB) and chlordanes. The concentrations of these POPs at Cape Verde were generally low and comparable to remote sites in the Arctic for several compounds. Seasonal trends varied between compounds and concentrations exhibited strong temperature dependence for chlordanes. Our results indicate net volatilization from the Atlantic Ocean north of Cape Verde as sources of these POPs. Air mass back trajectories demonstrated that air masses measured at Cape Verde were generally transported from the Atlantic Ocean or the North African continent. Overall, the low concentrations in air at Cape Verde were likely explained by absence of major emissions in areas from which the air masses originated combined with depletion during long-range atmospheric transport due to enhanced degradation under tropical conditions (high temperatures and concentrations of hydroxyl radicals). Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.
Bartkow, M.E.; Huckins, J.N.; Muller, J.F.
2004-01-01
Semipermeable membrane devices (SPMDs) have been used as passive air samplers of semivolatile organic compounds in a range of studies. However, due to a lack of calibration data for polyaromatic hydrocarbons (PAHs), SPMD data have not been used to estimate air concentrations of target PAHs. In this study, SPMDs were deployed for 32 days at two sites in a major metropolitan area in Australia. High-volume active sampling systems (HiVol) were co-deployed at both sites. Using the HiVol air concentration data from one site, SPMD sampling rates were measured for 12 US EPA Priority Pollutant PAHs and then these values were used to determine air concentrations at the second site from SPMD concentrations. Air concentrations were also measured at the second site with co-deployed HiVols to validate the SPMD results. PAHs mostly associated with the vapour phase (Fluorene to Pyrene) dominated both the HiVol and passive air samples. Reproducibility between replicate passive samplers was satisfactory (CV<20%) for the majority of compounds. Sampling rates ranged between 0.6 and 6.1 m3 d-1. SPMD-based air concentrations were calculated at the second site for each compound using these sampling rates and the differences between SPMD-derived air concentrations and those measured using a HiVol were, on average, within a factor of 1.5. The dominant processes for the uptake of PAHs by SPMDs were also assessed. Using the SPMD method described herein, estimates of particulate sorbed airborne PAHs with five rings or greater were within 1.8-fold of HiVol measured values. ?? 2004 Elsevier Ltd. All rights reserved.
The purpose of this SOP is to describe the procedure for sampling personal air for metals and pesticides during a predetermined time period. The SOP includes the set up of the samplers for collection of either a metals sample or a pesticides sample, the calibration and initial c...
Bowling, Frank L; Stickings, Daryl S; Edwards-Jones, Valerie; Armstrong, David G; Boulton, Andrew Jm
2009-05-08
The purpose of this study was to assess the level of air contamination with bacteria after surgical hydrodebridement and to determine the effectiveness of hydro surgery on bacterial reduction of a simulated infected wound. Four porcine samples were scored then infected with a broth culture containing a variety of organisms and incubated at 37 degrees C for 24 hours. The infected samples were then debrided with the hydro surgery tool (Versajet, Smith and Nephew, Largo, Florida, USA). Samples were taken for microbiology, histology and scanning electron microscopy pre-infection, post infection and post debridement. Air bacterial contamination was evaluated before, during and after debridement by using active and passive methods; for active sampling the SAS-Super 90 air sampler was used, for passive sampling settle plates were located at set distances around the clinic room. There was no statistically significant reduction in bacterial contamination of the porcine samples post hydrodebridement. Analysis of the passive sampling showed a significant (p < 0.001) increase in microbial counts post hydrodebridement. Levels ranging from 950 colony forming units per meter cubed (CFUs/m3) to 16780 CFUs/m3 were observed with active sampling of the air whilst using hydro surgery equipment compared with a basal count of 582 CFUs/m3. During removal of the wound dressing, a significant increase was observed relative to basal counts (p < 0.05). Microbial load of the air samples was still significantly raised 1 hour post-therapy. The results suggest a significant increase in bacterial air contamination both by active sampling and passive sampling. We believe that action might be taken to mitigate fallout in the settings in which this technique is used.
Final Report Yellow Bluff Air Study SESD Project ID #11-0068
On November 16 – December 16, 2010, and January 23 - 28, 2011, EPA conducted an air sampling study in Yellow Bluff, Alabama in response to concerns about potential health impacts related to air emissions emanating from a nearby paper mill.
Guo, Peng-ran; Lei, Yong-qian; Zhou, Qiao-li; Wang, Chang; Pan, Jia-chuan
2015-09-01
This study aimed to investigate the pollution degree and human health risk of heavy metals in soil and air samples around electroplating factories. Soil, air and waste gas samples were collected to measure 8 heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) in two electroplating factories, located in Baiyun district of Guangzhou city. Geoaccumulation index and USEPA Risk Assessment Guidance for Superfund (RAGS) were respectively carried out. Results showed that concentrations of Hg and Pb in waste gas and Cr in air samples were higher than limits of the corresponding quality standards, and concentrations of Cd, Hg and Zn in soil samples reached the moderate pollution level. The HQ and HI of exposure by heavy metals in air and soil samples were both lower than 1, indicating that there was no non-carcinogen risk. CRAs and CRCr in soil samples were beyond the maximum acceptable level of carcinogen risk (10(-4)), and the contribution rate of CRCr to TCR was over 81%. CRCr, CRNi and TCR in air samples were in range of 10(-6) - 10(-4), indicating there was possibly carcinogen risk but was acceptable risk. CR values for children were higher than adults in soils, but were higher for adults in air samples. Correlation analysis revealed that concentrations of heavy metals in soils were significantly correlated with these in waste gas samples, and PCA data showed pollution sources of Cd, Hg and Zn in soils were different from other metals.
NASA Astrophysics Data System (ADS)
Johnston, N. A. C.; Bundy, B. A.; Andrew, J. P.; Grimm, B. K.; Ketcherside, D.; Rivero-Zevallos, J. A.; Uhlorn, R. P.
2017-12-01
Lewiston, Idaho is a small city in the Snake River Valley bordering North-Central Idaho and Southeastern Washington, with a population of over 40,000 including the surrounding areas. One of the main industries and employers in the region is a kraft paper mill in North Lewiston, which results in odorous levels of sulfur air pollutants there. The Idaho Department of Environmental Quality has an air monitoring station in Lewiston but measures only air particulate matter (PM). Surprisingly, not much long-term data exists on this area for specific air constituents such as volatile organics, hazardous air pollutants, and sulfur compounds. One year-long study conducted in 2006-2007 by the Nez Perce Tribe found high formaldehyde levels in the area, and warranted further study in July of 2016-2017. Our ongoing study began in the fall of 2016 and investigates the seasonal air composition in the Lewiston area. Specifically, active air sampling via sorbent tubes and analysis by thermal desorption gas chromatography-mass spectrometry (TD-GC-MS). was utilized to measure over 50 volatile organic compounds, hazardous air pollutants, and sulfurous compounds in ambient air (adapted from EPA Method TO-17). Seasonal, diurnal, and spatial variations in air composition were explored with weekly to monthly grab sampling. Dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) were the primary sulfur compounds detected, and these varied considerably depending on time of day, season, location and meteorology. DMS was more prevalent in the summer months, while DMDS was more prevalent in the spring. Elevated concentrations of benzene and chloroform were found in the region during 2017, with average values of short term grab samples over three times the acceptable ambient concentrations in Idaho. These levels did not persist during longer term sampling of 12-hours, however further monitoring is needed to assess a potential health concern.
Preliminary study of the distribution of gaseous mercury species in the air of Guiyang city, China
NASA Astrophysics Data System (ADS)
Shang, L.; Feng, X.; Zheng, W.; Yan, H.
2003-05-01
Total gaseous mercury (TGM) in ambient air consists of Hg^0 and reactive gaseous mercury (RGM) in general. Although RGM only constitutes a small portion of TGM in the air, it contributes the most to both dry and wet deposition of mercury from the atmosphere. TGM and RGM concentrations in ambient air at one site of Guiyang City were determined in March 2002. TGM concentrations were monitored using an automated mercury vapor analyzer Tekran2537A, and RGM in ambient air was sampled using KCI coated tubular denuders. The sampled RGM denuders were analyzed using thermal desorption coupled with CVAFS detection. The average concentrations of TGM and RGM are 7.09 ng m^{-3} and 37.5pg m^{-3} respectively during the sampling period. The primary anthropogenic source for both Hg^0 and RGM is coal combustion in the study area. TGM concentrations are significantly elevated comparing to the global background values, whereas RGM concentrations are only slightly higher than the reported values in remote areas in Europe and US. RGM only constitutes 0.5% ofTGM in the air at the sampling period. There is a significant negative correlation between RGM concentration and relative humidity (RH), with a coefficient correlation of 0.39 (α<0.01). High relative humidity during the sampling is responsible for the relatively low RGM concentrations observed.
US EPA BASE Study Standard Operating Procedure for Sampling of Particulates
The objective of the procedure described is to collect a sample of particles of respirable and inhalable size (approx. 0.1 to 10 microns in diameter) from indoor air and from the outdoor air supplied to the indoor space tested.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Newton, G.J.; Hoover, M.D.
1995-12-01
Determination of the appropriate number and placement of air monitors in the workplace is quite subjective and is generally one of the more difficult tasks in radiation protection. General guidance for determining the number and placement of air sampling and monitoring instruments has been provided by technical reports such as Mishima, J. These two documents and other published guidelines suggest that some insight into sampler placement can be obtained by conducting airflow studies involving the dilution and clearance of the relatively inert tracer gas sulfur hexafluoride (SF{sub 6}) in sampler placement studies and describes the results of a study donemore » within the ITRI alpha inhalation exposure laboratories. The objectives of the study were to document an appropriate method for conducting SF{sub 6} dispersion studies, and to confirm the appropriate number and placement of air monitors and air samplers within a typical ITRI inhalation exposure laboratory. The results of this study have become part of the technical bases for air sampling and monitoring in the test room.« less
Avian influenza H9N2 virus isolated from air samples in LPMs in Jiangxi, China.
Zeng, Xiaoxu; Liu, Mingbin; Zhang, Heng; Wu, Jingwen; Zhao, Xiang; Chen, Wenbing; Yang, Lei; He, Fenglan; Fan, Guoyin; Wang, Dayan; Chen, Haiying; Shu, Yuelong
2017-07-24
Recently, avian influenza virus has caused repeated worldwide outbreaks in humans. Live Poultry Markets (LPMs) play an important role in the circulation and reassortment of novel Avian Influenza Virus (AIVs). Aerosol transmission is one of the most important pathways for influenza virus to spread among poultry, from poultry to mammals, and among mammals. In this study, air samples were collected from LPMs in Nanchang city between April 2014 and March 2015 to investigate possible aerosol transmission of AIVs. Air samples were detected for Flu A by Real-Time Reverse Transcription-Polymerase Chain Reaction (RRT-PCR). If samples were positive for Flu A, they were inoculated into 9- to 10-day-old specific-pathogen-free embryonated eggs. If the result was positive, the whole genome of the virus was sequenced by MiSeq. Phylogenetic trees of all 8 segments were constructed using MEGA 6.05 software. To investigate the possible aerosol transmission of AIVs, 807 air samples were collected from LPMs in Nanchang city between April 2014 and March 2015. Based on RRT-PCR results, 275 samples (34.1%) were Flu A positive, and one virus was successfully isolated with embryonated eggs. The virus shared high nucleotide homology with H9N2 AIVs from South China. Our study provides further evidence that the air in LPMs can be contaminated by influenza viruses and their nucleic acids, and this should be considered when choosing and evaluating disinfection strategies in LPMs, such as regular air disinfection. Aerosolized viruses such as the H9N2 virus detected in this study can increase the risk of human infection when people are exposed in LPMs.
Results from the 1987 total exposure assessment methodology (team) study in Southern California
NASA Astrophysics Data System (ADS)
Hartwell, T. D.; Perritt, R. L.; Pellizzari, E. D.; Michael, L. C.
Volatile organic compound (VOC) levels in breath, personal air and fixed-site (indoor and outdoor) air were measured and compared for a sample of 50 individuals in the Los Angeles area of California. Comparisons were also made between seasons (winter and summer), between breath samples taken at three different times during the 24-h monitoring period, and between exposure levels of smokers and non-smokers. Personal air levels were higher than indoor air levels and indoor levels were much higher than outdoor levels. Air concentrations in the kitchen and living area were quite similar. Air and breath levels were higher in the winter than in the summer. Little difference was found between levels for the three breath sampling periods. Mean personal air levels of VOCs related to smoking were higher in individuals exposed to tobacco smoke vs those who were not exposed. The personal air levels of smokers and passive smokers (those non-smokers exposed to tobacco smoke) were not significantly different; while similar air levels were found in the kitchen and primary living area of homes with smokers.
The Relationships between Air Exposure, Negative Pressure and Hemolysis
Pohlmann, Joshua R.; Toomasian, John M.; Hampton, Claire E.; Cook, Keith E.; Annich, Gail M.; Bartlett, Robert H.
2013-01-01
The purpose of this study was to describe the hemolytic effects of both negative pressure and an air-blood interface independently and in combination in an in-vitro static blood model. Samples of fresh ovine or human blood (5 mL) were subjected to a bubbling air interface (0–100 mL/min) or negative pressure (0–600 mmHg) separately, or in combination, for controlled periods of time, and analyzed for hemolysis. Neither negative pressure nor an air interface alone increased hemolysis. However, when air and negative pressure were combined, hemolysis increased as a function of negative pressure, the air interface, and time. Moreover, when blood samples were exposed to air prior to initiating the test, hemolysis was 4–5 times greater than samples not pre-exposed to air. When these experiments were repeated using freshly drawn human blood the same phenomena were observed, but the hemolysis was significantly higher than that observed in sheep blood. In this model, hemolysis is caused by combined air and negative pressure and is unrelated to either factor alone. PMID:19730004
1997-01-01
Not Sampled f PJ)ll PARSONS SAA - Some As Above Y Water level drilled LF-JENGINEERING SCIENCE.INC. Denver, Colorado L:\\45021\\,DRAWINGS\\BORELOGS\\OT-24...Remnediotion TS TOC - Top of Cosing G - GRAB MacDill Air Force Base, Florida NS- Not Sampled .PARUONU SAA - Same As Above VWater level drilled L!LJ...GRAB MacDill Air Force Base. Florida NS - Not Sampled fj•--PAMMMNuI SAA - Some As Above Y Water level drilled *NIIN I N Denver. Colorado L:\\45021
NASA Astrophysics Data System (ADS)
Johnson, Markey M.; Williams, Ron; Fan, Zhihua; Lin, Lin; Hudgens, Edward; Gallagher, Jane; Vette, Alan; Neas, Lucas; Özkaynak, Halûk
2010-12-01
The Mechanistic Indicators of Childhood Asthma (MICA) study in Detroit, Michigan introduced a participant-based approach to reduce the resource burden associated with collection of indoor and outdoor residential air sampling data. A subset of participants designated as MICA-Air conducted indoor and outdoor residential sampling of nitrogen dioxide (NO 2), volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs). This participant-based methodology was subsequently adapted for use in the Vanguard phase of the U.S. National Children's Study. The current paper examines residential indoor and outdoor concentrations of these pollutant species among health study participants in Detroit, Michigan. Pollutants measured under MICA-Air agreed well with other studies and continuous monitoring data collected in Detroit. For example, NO 2 and BTEX concentrations reported for other Detroit area monitoring were generally within 10-15% of indoor and outdoor concentrations measured in MICA-Air households. Outdoor NO 2 concentrations were typically higher than indoor NO 2 concentration among MICA-Air homes, with a median indoor/outdoor (I/O) ratio of 0.6 in homes that were not impacted by environmental tobacco smoke (ETS) during air sampling. Indoor concentrations generally exceeded outdoor concentrations for VOC and PAH species measured among non-ETS homes in the study. I/O ratios for BTEX species (benzene, toluene, ethylbenzene, and m/p- and o-xylene) ranged from 1.2 for benzene to 3.1 for toluene. Outdoor NO 2 concentrations were approximately 4.5 ppb higher on weekdays versus weekends. As expected, I/O ratios pollutants were generally higher for homes impacted by ETS. These findings suggest that participant-based air sampling can provide a cost-effective alternative to technician-based approaches for assessing indoor and outdoor residential air pollution in community health studies. We also introduced a technique for estimating daily concentrations at each home by weighting 2- and 7-day integrated concentrations using continuous measurements from regulatory monitoring sites. This approach may be applied to estimate short-term daily or hourly pollutant concentrations in future health studies.
Luksamijarulkul, Pipat; Suknongbung, Siranee; Vatanasomboon, Pisit; Sujirarut, Dusit
2017-03-01
A large number of migrants have move to cities in Thailand seeking employment. These people may be at increased risk for environmental health problems. We studied the health status, environmental living conditions and microbial indoor air quality (IAQ) among selected groups of migrant workers and their households in Mueang District, Samut Sakhon, central Thailand. We conducted a cross sectional study of 240 migrant workers and their households randomly selected by multistage sampling. The person responsible for hygiene at each studied household was interviewed using a structured questionnaire. Two indoor air samples were taken from each household (480 indoor air samples) to determine bacterial and fungal counts using a Millipore air tester; 240 outdoor air samples were collected for comparison. Ninety-nine point six percent of study subjects were Myanmar, 74.2% were aged 21-40 years, 91.7% had a primary school level education or lower and 53.7% had stayed in Thailand less than 5 years. Eight point three percent had a history of an underlying disease, 20.8% had a recent history of pulmonary tuberculosis in a family member within the previous year. Forty-three point eight percent had a current illness related to IAQ during a previous month. Twenty-one point three were current cigarette smokers, 15.0% were current alcohol consumers, and 5.0% exercises ≥3 times per week. Forty-nine point two percent never opened the windows of their bedrooms or living rooms for ventilation, 45% never cleaned their window screens, and 38.3% never put their pillows or mattresses in the sunlight. The mean(±SD) air bacterial count was 230(±229) CFU/m3 (outdoor air = 128±82 CFU/ m3), and the mean fungal count was 630(±842) CFU/m3 (outdoor air = 138±94 CFU/ m3). When the bacterial and fungal counts were compared with the guidelines of the American Conference of Governmental Industrial Hygienists, the bacterial counts in 6.5% of houses surveyed and the fungal counts in 28.8% of house surveyed were higher than the recommended levels (<500 CFU/m3). Bacterial and fungal counts in the sample households were not significantly correlated with household hygiene practice scores (p>0.05). There was a positive correlation between bacterial counts and fungal counts in household air samples, r=0.28, p<0.001.
Mirzaee, Seyyed Abbas; Nikaeen, Mahnaz; Hajizadeh, Yaghob; Nabavi, BiBi Fatemeh; Hassanzadeh, Akbar
2015-01-01
Background: Wastewater contains a variety of pathogens and bio -aerosols generated during the wastewater treatment process, which could be a potential health risk for exposed individuals. This study was carried out to detect Legionella spp. in the bio -aerosols generated from different processes of a wastewater treatment plant (WWTP) in Isfahan, Iran, and the downwind distances. Materials and Methods: A total of 54 air samples were collected and analyzed for the presence of Legionella spp. by a nested- polymerase chain reaction (PCR) assay. A liquid impingement biosampler was used to capture bio -aerosols. The weather conditions were also recorded. Results: Legionella were detected in 6% of the samples, including air samples above the aeration tank (1/9), belt filter press (1/9), and 250 m downwind (1/9). Conclusion: The result of this study revealed the presence of Legionella spp. in air samples of a WWTP and downwind distance, which consequently represent a potential health risk to the exposed individuals. PMID:25802817
Gibbs, Jenna L.; Yost, Michael G.; Negrete, Maria; Fenske, Richard A.
2016-01-01
Background: Recent studies have highlighted the increased potency of oxygen analogs of organophosphorus pesticides. These pesticides and oxygen analogs have previously been identified in the atmosphere following spray applications in the states of California and Washington. Objectives: We used two passive sampling methods to measure levels of the ollowing organophosphorus pesticides: chlorpyrifos, azinphos-methyl, and their oxygen analogs at 14 farmworker and 9 non-farmworker households in an agricultural region of central Washington State in 2011. Methods: The passive methods included polyurethane foam passive air samplers deployed outdoors and indoors and polypropylene deposition plates deployed indoors. We collected cumulative monthly samples during the pesticide application seasons and during the winter season as a control. Results: Monthly outdoor air concentrations ranged from 9.2 to 199 ng/m3 for chlorpyrifos, 0.03 to 20 ng/m3 for chlorpyrifos-oxon, < LOD (limit of detection) to 7.3 ng/m3 for azinphos-methyl, and < LOD to 0.8 ng/m3 for azinphos-methyl-oxon. Samples from proximal households (≤ 250 m) had significantly higher outdoor air concentrations of chlorpyrifos, chlorpyrifos-oxon, and azinphos-methyl than did samples from nonproximal households (p ≤ 0.02). Overall, indoor air concentrations were lower than outdoors. For example, all outdoor air samples for chlorpyrifos and 97% of samples for azinphos-methyl were > LOD. Indoors, only 78% of air samples for chlorpyrifos and 35% of samples for azinphos-methyl were > LOD. Samples from farmworker households had higher indoor air concentrations of both pesticides than did samples from non-farmworker households. Mean indoor and outdoor air concentration ratios for chlorpyrifos and azinphos-methyl were 0.17 and 0.44, respectively. Conclusions: We identified higher levels in air and on surfaces at both proximal and farmworker households. Our findings further confirm the presence of pesticides and their oxygen analogs in air and highlight their potential for infiltration of indoor living environments. Citation: Gibbs JL, Yost MG, Negrete M, Fenske RA. 2017. Passive sampling for indoor and outdoor exposures to chlorpyrifos, azinphos-methyl, and oxygen analogs in a rural agricultural community. Environ Health Perspect 125:333–341; http://dx.doi.org/10.1289/EHP425 PMID:27517732
Mold contamination in a controlled hospital environment: a 3-year surveillance in southern Italy.
Caggiano, Giuseppina; Napoli, Christian; Coretti, Caterina; Lovero, Grazia; Scarafile, Giancarlo; De Giglio, Osvalda; Montagna, Maria Teresa
2014-11-15
Environmental monitoring of airborne filamentous fungi is necessary to reduce fungal concentrations in operating theaters and in controlled environments, and to prevent infections. The present study reports results of a surveillance of filamentous fungi carried out on samples from air and surfaces in operating theaters and controlled environments in an Italian university hospital. Sampling was performed between January 2010 and December 2012 in 32 operating theaters and five departments with high-risk patients. Indoor air specimens were sampled using a microbiological air sampler; Rodac contact plates were used for surface sampling. Fungal isolates were identified at the level of genera and species. Sixty-one samples (61/465; 13.1%) were positive for molds, with 18 from controlled environments (18/81; 22.2%) and 43 (43/384; 11.2%) from operating theaters. The highest air fungal load (AFL, colony-forming units per cubic meter [CFU/m(3)]) was recorded in the ophthalmology operating theater, while the pediatric onco-hematology ward had the highest AFL among the wards (47 CFU/m(3)). The most common fungi identified from culture of air specimens were Aspergillus spp. (91.8%), Penicillium spp., (6%) and Paecilomyces spp. (1.5%). During the study period, a statistically significant increase in CFU over time was recorded in air-controlled environments (p = 0.043), while the increase in AFL in operating theaters was not statistically significant (p = 0.145). Molds were found in 29.1% of samples obtained from surfaces. Aspergillus fumigatus was the most commonly isolated (68.5%). Our findings will form the basis for action aimed at improving the air and surface quality of these special wards. The lack of any genetic analysis prevented any correlation of fungal environmental contamination with onset of fungal infection, an analysis that will be undertaken in a prospective study in patients admitted to the same hospital.
Relationship between vapor intrusion and human exposure to trichloroethylene.
Archer, Natalie P; Bradford, Carrie M; Villanacci, John F; Crain, Neil E; Corsi, Richard L; Chambers, David M; Burk, Tonia; Blount, Benjamin C
2015-01-01
Trichloroethylene (TCE) in groundwater has the potential to volatilize through soil into indoor air where it can be inhaled. The purpose of this study was to determine whether individuals living above TCE-contaminated groundwater are exposed to TCE through vapor intrusion. We examined associations between TCE concentrations in various environmental media and TCE concentrations in residents. For this assessment, indoor air, outdoor air, soil gas, and tap water samples were collected in and around 36 randomly selected homes; blood samples were collected from 63 residents of these homes. Additionally, a completed exposure survey was collected from each participant. Environmental and blood samples were analyzed for TCE. Mixed model multiple linear regression analyses were performed to determine associations between TCE in residents' blood and TCE in indoor air, outdoor air, and soil gas. Blood TCE concentrations were above the limit of quantitation (LOQ; ≥ 0.012 µg L(-1)) in 17.5% of the blood samples. Of the 36 homes, 54.3%, 47.2%, and >84% had detectable concentrations of TCE in indoor air, outdoor air, and soil gas, respectively. Both indoor air and soil gas concentrations were statistically significantly positively associated with participants' blood concentrations (P = 0.0002 and P = 0.04, respectively). Geometric mean blood concentrations of residents from homes with indoor air concentrations of >1.6 µg m(-3) were approximately 50 times higher than geometric mean blood TCE concentrations in participants from homes with no detectable TCE in indoor air (P < .0001; 95% CI 10.4-236.4). This study confirms the occurrence of vapor intrusion and demonstrates the magnitude of exposure from vapor intrusion of TCE in a residential setting.
Relationship between vapor intrusion and human exposure to trichloroethylene
ARCHER, NATALIE P.; BRADFORD, CARRIE M.; VILLANACCI, JOHN F.; CRAIN, NEIL E.; CORSI, RICHARD L.; CHAMBERS, DAVID M.; BURK, TONIA; BLOUNT, BENJAMIN C.
2015-01-01
Trichloroethylene (TCE) in groundwater has the potential to volatilize through soil into indoor air where it can be inhaled. The purpose of this study was to determine whether individuals living above TCE-contaminated groundwater are exposed to TCE through vapor intrusion. We examined associations between TCE concentrations in various environmental media and TCE concentrations in residents. For this assessment, indoor air, outdoor air, soil gas, and tap water samples were collected in and around 36 randomly selected homes; blood samples were collected from 63 residents of these homes. Additionally, a completed exposure survey was collected from each participant. Environmental and blood samples were analyzed for TCE. Mixed model multiple linear regression analyses were performed to determine associations between TCE in residents' blood and TCE in indoor air, outdoor air, and soil gas. Blood TCE concentrations were above the limit of quantitation (LOQ; ≥0.012 μg/L) in 17.5% of the blood samples. Of the 36 homes, 54.3%, 47.2%, and >84% had detectable concentrations of TCE in indoor air, outdoor air, and soil gas, respectively. Both indoor air and soil gas concentrations were statistically significantly positively associated with participants' blood concentrations (p=0.0002 and p=0.04, respectively). Geometric mean blood concentrations of residents from homes with indoor air concentrations of >1.6 μg/m3 were approximately 50 times higher than geometric mean blood TCE concentrations in participants from homes with no detectable TCE in indoor air (p<.0001; 95% CI 10.4 – 236.4). This study confirms the occurrence of vapor intrusion and demonstrates the magnitude of exposure from vapor intrusion of TCE in a residential setting. PMID:26259926
NASA Astrophysics Data System (ADS)
Wu, Xiangmei (May); Fan, Zhihua (Tina); Zhu, Xianlei; Jung, Kyung Hwa; Ohman-Strickland, Pamela; Weisel, Clifford P.; Lioy, Paul J.
2012-09-01
To address disparities in health risks associated with ambient air pollution for racial/ethnic minority groups, this study characterized personal and ambient concentrations of volatile organic compounds (VOCs) in a suspected hot spot of air pollution - the Village of Waterfront South (WFS), and an urban reference community - the Copewood/Davis Streets (CDS) neighborhood in Camden, New Jersey. Both are minority-dominant, impoverished communities. We collected 24-h integrated personal air samples from 54 WFS residents and 53 CDS residents, with one sample on a weekday and one on a weekend day during the summer and winter seasons of 2004-2006. Ambient air samples from the center of each community were also collected simultaneously during personal air sampling. Toluene, ethylbenzene, and xylenes (TEX) presented higher (p < 0.05) ambient levels in WFS than in CDS, particularly during weekdays. A stronger association between personal and ambient concentrations of MTBE and TEX was found in WFS than in CDS. Fourteen to forty-two percent of the variation in personal MTBE, hexane, benzene, and TEX was explained by local outdoor air pollution. These observations indicated that local sources impacted the community air pollution and personal exposure in WFS. The estimated cancer risks resulting from two locally emitted VOCs, benzene and ethylbenzene, and non-cancer neurological and respiratory effects resulting from hexane, benzene, toluene, and xylenes exceeded the US EPA risk benchmarks in both communities. These findings emphasized the need to address disparity in health risks associated with ambient air pollution for the socio-economically disadvantaged groups. This study also demonstrated that air pollution hot spots similar to WFS can provide robust setting to investigate health effects of ambient air pollution.
The use of an air filtration system in podiatry clinics.
McLarnon, Nichola; Burrow, Gordon; Maclaren, William; Aidoo, Kofi; Hepher, Mike
2003-06-01
A small-scale study was conducted to ascertain the efficiency and effectiveness of an air filtration system for use in podiatry/chiropody clinics (Electromedia Model 35F (A), Clean Air Ltd, Scotland, UK). Three clinics were identified, enabling comparison of data between podiatry clinics in the West of Scotland. The sampling was conducted using a portable Surface Air Sampler (Cherwell Laboratories, Bicester, UK). Samples were taken on two days at three different times before and after installation of the filtration units. The global results of the study indicate the filter has a statistically significant effect on microbial counts, with an average percentage decrease of 65%. This study is the first time, to the authors' knowledge, such a system has been tested within podiatric practice.
NASA Astrophysics Data System (ADS)
Hyttinen, Marko; Masalin-Weijo, Marika; Kalliokoski, Pentti; Pasanen, Pertti
2010-12-01
Heat-treated wood is an increasingly popular decoration material. Heat-treatment improves dimensional stability of the wood and also prevents rot fungus growth. Although production of heat-treated wood has been rapidly increasing, there is only little information about the VOC emissions of heat-treated wood and its possible influences on indoor air quality. In the present study, VOC emissions from three untreated (air-dried) and heat-treated wood species were compared during a four weeks test period. It appeared that different wood species had clearly different VOC emission profiles. Heat-treatment was found to decrease VOC emissions significantly and change their composition. Especially, emissions of terpenes decreased from softwood samples and aldehydes from European aspen samples. Emissions of total aldehydes and organic acids were at the same level or slightly higher from heat treated than air-dried softwood samples. In agreement with another recent study, the emissions of furfural were found to increase and those of hexanal to decrease from all the wood species investigated. In contrast to air-dried wood samples, emissions of VOCs were almost in steady state from heat treated wood samples even in the beginning of the test.
Tsiropoulos, Nikolaos G; Bakeas, Evangelos B; Raptis, Vasilios; Batistatou, Stavroula S
2006-07-28
A methodology is described for greenhouse air analysis by sampling fenhexamid, pyrimethanil, malathion, metalaxyl-M and myclobutanil in solid sorbents. Pesticides were determined by gas chromatography with NP Detector. The trapping efficiency of XAD-2, XAD-4, Supelpak-2, Florisil and C-18 at different sampling conditions (rate, time and air humidity) and pesticides concentration levels has been evaluated. No breakthrough was observed in the range of concentration studied (0.10-75 microg of each pesticide). In almost all the cases good stability results were obtained. Personal pumps have been used with selected sorbents (Supelpak-2 and C-18) in order to sample malathion and fenhexamid in air of experimental greenhouse after their application in a tomato crop. The dissipation process of the analytes in various time periods after application has been studied. Malathion concentrations varied between 20.1 microg m(-3) just after application and 1.06 microg m(-3) 3 days later. Fenhexamid concentrations, determined by high performance liquid chromatography with UV detection, fall rapidly; after 12 h post-application being below 0.50 microg m(-3).
Oxidation Behavior of Ferritic Stainless Steels under SOFC Interconnect Exposure Conditions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Zhenguo; Walker, Matthew S.; Singh, Prabhakar
The oxidation of ferritic stainless steels has been studied under solid oxide fuel cell (SOFC) interconnect “dual” exposure conditions, i.e. simultaneous exposure to air on one side of the sample, and moist hydrogen on the other side. This paper focuses on the oxidation behavior of ferritic stainless steels during the isothermal oxidation in the dual environments. It was found that scales grown on the air side under these dual exposure conditions can be significantly different from scales grown on samples exposed to air on both sides. In contrast, no substantial difference was observed between the scales grown on the fuelmore » side of the dual atmosphere samples and scales grown on samples exposed to moist hydrogen on both sides. AISI430, with 17% Cr, suffered localized attack via formation of Fe2O3 hematite-rich nodules on the air side of dual exposure samples, while the spinel top layer of the air side scale of Crofer22 APU (23% Cr) was enriched in iron. For E-brite, with the highest Cr content (27%), no unusual phases were found in the scale on the air side, but it was noticed the air side scale was less dense and appeared to be more prone to defects than the scale grown in air only. The anomalous oxidation behavior of ferritic stainless steels on the air side of dual exposure specimens is related to the transport of hydrogen through the steel and its subsequent presence in the air side scale.« less
Pacheco, J M; Brito, B; Hartwig, E; Smoliga, G R; Perez, A; Arzt, J; Rodriguez, L L
2017-04-01
Foot-and-mouth disease (FMD) is a highly contagious livestock disease of high economic impact. Early detection of FMD virus (FMDV) is fundamental for rapid outbreak control. Air sampling collection has been demonstrated as a useful technique for detection of FMDV RNA in infected animals, related to the aerogenous nature of the virus. In the current study, air from rooms housing individual (n = 17) or two groups (n = 4) of cattle experimentally infected with FDMV A24 Cruzeiro of different virulence levels was sampled to assess the feasibility of applying air sampling as a non-invasive, screening tool to identify sources of FMDV infection. Detection of FMDV RNA in air was compared with first detection of clinical signs and FMDV RNA levels in serum and oral fluid. FMDV RNA was detected in room air samples 1-3 days prior (seven animals) or on the same day (four animals) as the appearance of clinical signs in 11 of 12 individually housed cattle. Only in one case clinical signs preceded detection in air samples by one day. Overall, viral RNA in oral fluid or serum preceded detection in air samples by 1-2 days. Six individually housed animals inoculated with attenuated strains did not show clinical signs, but virus was detected in air in one of these cases 3 days prior to first detection in oral fluid. In groups of four cattle housed together, air detection always preceded appearance of clinical signs by 1-2 days and coincided more often with viral shedding in oral fluid than virus in blood. These data confirm that air sampling is an effective non-invasive screening method for detecting FMDV infection in confined to enclosed spaces (e.g. auction barns, milking parlours). This technology could be a useful tool as part of a surveillance strategy during FMD prevention, control or eradication efforts. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
Passive sampling of gas-phase air toxics and criteria pollutants has become an attractive monitoring method in human exposure studies due to the relatively low sampling cost and ease of use. This study evaluates the performance of Model 3300 Ogawa(TM) Passive NO2 Samplers and 3...
NASA Astrophysics Data System (ADS)
Mayer, Simon; Jenner, Florian; Aeschbach, Werner
2017-04-01
Applications of inert gases in groundwater hydrology require a profound understanding of underlying biogeochemical processes. Some of these processes are, however, not well understood and therefore require further investigation. This is the first study simultaneously investigating soil air and groundwater in the context of noble gas tracer applications, accounting for seasonal effects in different climate regions. The sampled data confirm a general reliability of common assumptions proposed in the literature. In particular, a solubility-controlled description of excess air formation and of groundwater degassing can be confirmed. This study identifies certain effects which need to be taken into account to reliably evaluate noble gas patterns. First, long-term samplings suggest a permanent temperature-driven equilibration of shallow groundwater with entrapped air bubbles, even some years after recharge. Second, minor groundwater degassing is found to challenge existing excess air model approaches, depending on the amount and the fractionation of excess air. Third, soil air composition data of this study imply a potential bias of noble gas temperatures by up to about 2℃ due to microbial oxygen depletion and a reduced sum value of O2+CO2. This effect causes systematically lower noble gas temperatures in tropical groundwater samples and in shallow mid-latitude groundwater samples after strong recharge during the warm season. However, a general bias of noble gas temperatures in mid-latitudes is probably prevented by a predominant recharge during the cold season, accompanied by nearly atmospheric noble gas mixing ratios in the soil air. Findings of this study provide a remarkable contribution to the reliability of noble gas tracer applications in hydrology, in particular with regard to paleoclimate reconstructions and an understanding of subsurface gas dynamics.
Study on Aerosol Penetration Through Clothing and Individual Protective Equipment
2009-05-01
8.4X10-3 mg.m-3 (2.57X105 particles per cubic meter of air) over a 30 minute period. This scenario represents a very high end threat with a large... Isokinetic air sampling was applied and the effect of aerosol losses in sampling lines and other parts of the test rig were incorporated in analysis...eliminate any “memory” effect. The aerosol sampling (airflow direction control, start of sampling) was operated manually. Isokinetic sampling conditions
Bender, David A.; Rowe, Barbara L.
2015-01-01
Ellsworth Air Force Base is an Air Combat Command located approximately 10 miles northeast of Rapid City, South Dakota. Ellsworth Air Force Base occupies about 6,000 acres within Meade and Pennington Counties, and includes runways, airfield operations, industrial areas, housing, and recreational facilities. Fuels Area C within Ellsworth Air Force Base is a fuels storage area that is used to support the mission of the base. In fall of 2013, the U.S. Geological Survey began a study in cooperation with the U.S. Air Force, Ellsworth Air Force Base, to estimate groundwater-flow direction, select locations for permanent monitoring wells, and install and sample monitoring wells for petroleum hydrocarbon compounds within Fuels Area C. Nine monitoring wells were installed for the study within Fuels Area C during November 4–7, 2014. Soil core samples were collected during installation of eight of the monitoring wells and analyzed for benzene, toluene, ethylbenzene, total xylenes, naphthalene,m- and p-xylene, o-xylene, and gasoline- and diesel-range organic compounds. Groundwater samples were collected from seven of the nine wells (two of the monitoring wells did not contain enough water to sample or were dry) during November 19–21, 2014, and analyzed for select physical properties, benzene, toluene, ethylbenzene, total xylenes, naphthalene, m- and p-xylene, o-xylene, and gasoline- and diesel-range organic compounds. This report describes the nine monitoring well locations and presents the soil- and groundwater-quality data collected in 2014 for this study.
NASA Astrophysics Data System (ADS)
Wu, Ted Hsin-Yeh
A region of concern for persistent organic pollutants (POPS) contamination is the Arctic, because of POPs' ability to migrate long distances through the atmosphere toward cold regions, condense out of the atmosphere in those region, deposit in sensitive arctic ecosystems and bioaccumulate in Arctic species. Thus, monitoring of POP concentrations in the Arctic is necessary. However, traditional active air monitoring techniques for POPs may not be feasible in the Arctic, because of logistics and cost. While these issues may be overcome using passive air sampling devices, questions arise about the interpretation of the contaminant concentrations detected using the passive air samplers. In this dissertation semi-permeable membrane devices (SPMDs) containing triolein were characterized and evaluated for use in sampling the ambient air of Alaska for three classes of POPS (organochlorines [OCs], polychlorinated biphenyls [PCBs] and polyaromatic hydrocarbons [PAHs]). In addition, a SPMD-based sampling campaign for POPS was conducted simultaneously at five sites in Alaska during a one-year period. The POP concentrations obtained from the SPMDs were examined to determine the spatial and seasonal variability at the locations. POP concentrations detected in SPMDs were influenced by exposure to sunlight, concentrations of particulate-bound contaminants and changes in temperature. PAH concentrations in a SPMD mounted in a sunlight-blocking deployment unit were higher than in a SPMD exposed to sunlight (P = 0.007). PCB concentrations in SPMD exposed to filtered and non-filtered air were significantly different (P < 0.0001). Derived PAH air concentrations measured using SPMD were within a factor of approximately 7 of those obtained from an air sampler in Barrow, Alaska. The field study showed three distinct groups of samples. Barrow was separated from the sub-Arctic samples and a Homer sample (September-December) was distinct from the sub-Arctic samples. The separations suggest different air masses are being sampled by SPMDs. Lower concentrations of total POPs were measured at the coastal sites than the Interior sites.
Microbiological contamination of compressed air used in dentistry: an investigation.
Conte, M; Lynch, R M; Robson, M G
2001-11-01
The purpose of this preliminary investigation was twofold: 1) to examine the possibility of cross-contamination between a dental-evacuation system and the compressed air used in dental operatories and 2) to capture and identify the most common microflora in the compressed-air supply. The investigation used swab, water, and air sampling that was designed to track microorganisms from the evacuation system, through the air of the mechanical room, into the compressed-air system, and back to the patient. Samples taken in the vacuum system, the air space in the mechanical room, and the compressed-air storage tank had significantly higher total concentrations of bacteria than the outside air sampled. Samples of the compressed air returning to the operatory were found to match the outside air sample in total bacteria. It was concluded that the air dryer may have played a significant role in the elimination of microorganisms from the dental compressed-air supply.
Air Pollution Source/receptor Relationships in South Coast Air Basin, CA
NASA Astrophysics Data System (ADS)
Gao, Ning
This research project includes the application of some existing receptor models to study the air pollution source/receptor relationships in the South Coast Air Basin (SoCAB) of southern California, the development of a new receptor model and the testing and the modifications of some existing models. These existing receptor models used include principal component factor analysis (PCA), potential source contribution function (PSCF) analysis, Kohonen's neural network combined with Prim's minimal spanning tree (TREE-MAP), and direct trilinear decomposition followed by a matrix reconstruction. The ambient concentration measurements used in this study are a subset of the data collected during the 1987 field exercise of Southern California Air Quality Study (SCAQS). It consists of a number of gaseous and particulate pollutants analyzed from samples collected by SCAQS samplers at eight sampling sites, Anaheim, Azusa, Burbank, Claremont, Downtown Los Angeles, Hawthorne, Long Beach, and Rubidoux. Based on the information of emission inventories, meteorology and ambient concentrations, this receptor modeling study has revealed mechanisms that influence the air quality in SoCAB. Some of the mechanisms affecting the air quality in SoCAB that were revealed during this study include the following aspects. The SO_2 collected at sampling sites is mainly contributed by refineries in the coastal area and the ships equipped with oil-fired boilers off shore. Combustion of fossil fuel by automobiles dominates the emission of NO_{rm x} that is subsequently transformed and collected at sampling sites. Electric power plants also contribute HNO_3 to the sampling sites. A large feedlot in the eastern region of SoCAB has been identified as the major source of NH_3. Possible contributions from other industrial sources such as smelters and incinerators were also revealed. The results of this study also suggest the possibility of DMS (dimethylsulfide) and NH_3 emissions from off-shore sediments that have been contaminated by waste sludge disposal. The study also discovered that non-anthropogenic sources account for the observation of many chemical components being brought to the sampling sites, such as seasalt particles, soil particles, and Cl emission from Mojave Desert. The potential and limitation of the receptor models have been evaluated and some modifications have been made to improve the value of the models. A source apportionment method has been developed based on the application results of the potential source contribution function (PSCF) analysis.
Near-infrared spectroscopy (NIRS) as a tool to monitor exhaust air from poultry operations.
Druckenmüller, Katharina; Günther, Klaus; Elbers, Gereon
2018-07-15
Intensive poultry operation systems emit a considerable volume of inorganic and organic matter in the surrounding environment. Monitoring cleaning properties of exhaust air cleaning systems and to detect small but significant changes in emission characteristics during a fattening cycle is important for both emission and fattening process control. In the present study, we evaluated the potential of near-infrared spectroscopy (NIRS) combined with chemometric techniques as a monitoring tool of exhaust air from poultry operation systems. To generate a high-quality data set for evaluation, the exhaust air of two poultry houses was sampled by applying state-of-the-art filter sampling protocols. The two stables were identical except for one crucial difference, the presence or absence of an exhaust air cleaning system. In total, twenty-one exhaust air samples were collected at the two sites to monitor spectral differences caused by the cleaning device, and to follow changes in exhaust air characteristics during a fattening period. The total dust load was analyzed by gravimetric determination and included as a response variable in multivariate data analysis. The filter samples were directly measured with NIR spectroscopy. Principal component analysis (PCA), linear discriminant analysis (LDA), and factor analysis (FA) were effective in classifying the NIR exhaust air spectra according to fattening day and origin. The results indicate that the dust load and the composition of exhaust air (inorganic or organic matter) substantially influence the NIR spectral patterns. In conclusion, NIR spectroscopy as a tool is a promising and very rapid way to detect differences between exhaust air samples based on still not clearly defined circumstances triggered during a fattening period and the availability of an exhaust air cleaning system. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alexander, W.J.; Liddle, S.K.
1986-09-01
The primary objectives of this project were to collect and analyze groundwater, surface water, and sediment samples and to perform an initial characterization of the hydrogeochemical regime at potential contamination sites on Shaw Air Force Base near Sumter, South Carolina. This study constituted Phase II of the U.S. Air Force Installation Restoration Program (IRP). Five potential sources of groundwater pollution were studied. The evaluation primarily included the drilling of soil test borings, the installation, development, and sampling of groundwater monitoring wells, and the analyses of soil, surface water, and groundwater samples. Also used in the study were field measurements ofmore » water quality, water-level measurements site observations, published hydrogeologic data and Shaw AFB documents.« less
Hazrati, Sadegh; Harrad, Stuart
2007-03-01
PUF disk passive air samplers are increasingly employed for monitoring of POPs in ambient air. In order to utilize them as quantitative sampling devices, a calibration experiment was conducted. Time integrated indoor air concentrations of PCBs and PBDEs were obtained from a low volume air sampler operated over a 50 d period alongside the PUF disk samplers in the same office microenvironment. Passive sampling rates for the fully-sheltered sampler design employed in our research were determined for the 51 PCB and 7 PBDE congeners detected in all calibration samples. These values varied from 0.57 to 1.55 m3 d(-1) for individual PCBs and from 1.1 to 1.9 m3 d(-1) for PBDEs. These values are appreciably lower than those reported elsewhere for different PUF disk sampler designs (e.g. partially sheltered) employed under different conditions (e.g. in outdoor air), and derived using different calibration experiment configurations. This suggests that sampling rates derived for a specific sampler configuration deployed under specific environmental conditions, should not be extrapolated to different sampler configurations. Furthermore, our observation of variable congener-specific sampling rates (consistent with other studies), implies that more research is required in order to understand fully the factors that influence sampling rates. Analysis of wipe samples taken from the inside of the sampler housing, revealed evidence that the housing surface scavenges particle bound PBDEs.
Mendez, Gregory O.; Foreman, William T.; Sidhu, Jagdeep S.; Majewski, Michael S.
2007-01-01
In 1998, the U.S. Geological Survey, in cooperation with the Sweetwater Authority, began a study to assess the overall health of the Sweetwater watershed with respect to chemical contamination. The study included regular sampling of air and water at Sweetwater Reservoir for chemical contaminants, including volatile organic compounds, polycyclic aromatic hydrocarbons, pesticides, and major and trace elements. Background water samples were collected at Loveland Reservoir for volatile organic compounds and pesticides. The purpose of this study was to monitor changes in contaminant composition and concentration in the air and water resulting from the construction and operation of State Route 125 near Sweetwater Reservoir. To accomplish this, the study was divided into two phases. Phase One sampling was designed to establish baseline conditions for target compounds in terms of detection frequency and concentration in air and water. Phase Two sampling is planned to continue at the established monitoring sites during and after construction of State Route 125 to assess the chemical impact this roadway alignment project may have on the water quality in the reservoir. In addition to the ongoing data collection, several special studies were initiated to assess the occurrence of specific chemicals of concern, such as low-use pesticides, trace metals, and wastewater compounds. This report describes the study design, and the sampling and analytical methods, and presents the results for the second and third years of the study (October 1999 to September 2001). Data collected during the first year of sampling (October 1998 to September 1999) were published in 2002.
Lohmann, Rainer; Jaward, Foday M; Durham, Louise; Barber, Jonathan L; Ockenden, Wendy; Jones, Kevin C; Bruhn, Regina; Lakaschus, Soenke; Dachs, Jordi; Booij, Kees
2004-07-15
Air samples were taken onboard the RRS Bransfield on an Atlantic cruise from the United Kingdom to Halley, Antarctica, from October to December 1998, with the aim of establishing PCB oceanic background air concentrations and assessing their latitudinal distribution. Great care was taken to minimize pre- and post-collection contamination of the samples, which was validated through stringent QA/QC procedures. However, there is evidence that onboard contamination of the air samples occurred,following insidious, diffusive emissions on the ship. Other data (for PCBs and other persistent organic pollutants (POPs)) and examples of shipboard contamination are presented. The implications of these findings for past and future studies of global POPs distribution are discussed. Recommendations are made to help critically appraise and minimize the problems of insidious/diffusive shipboard contamination.
Nieguitsila, Adélaïde; Arné, Pascal; Durand, Benoît; Deville, Manjula; Benoît-Valiergue, Hélène; Chermette, René; Cottenot-Latouche, Sophie; Guillot, Jacques
2011-02-01
Fungal elements represent a significant part of the biological contaminants that could be detected in the air of animal facilities. The aim of this study was to assess the relative efficiencies of two air sampling methods and three culture conditions for the quantification of airborne culturable fungi in a poultry farmhouse in France. Air samples were collected every week throughout a 15-week period. Two devices were simultaneously used-a rotative cup air sampler (CIP 10-M, Arelco, France) and an air sampler based on filtration (AirPort MD8, Sartorius, Germany). Culture of airborne viable fungi was performed on malt extract agar (ME) and dichloran glycerol-18 (DG18) at 25 or 37°C. CIP 10-M and AirPort MD8 were shown to display comparable performances but significant differences were observed between culture conditions for Aspergillus spp. (p<0.01), Scopulariopsis spp. (p=0.02) and unidentified molds (p<0.01). Copyright © 2010 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Senthil Kumar, R.; Rajkumar, P.
2014-11-01
The abstract of this paper explains the presence of minerals in air which causes great concern regarding public health issues. The spectroscopic investigation of air dust particles of several samples in various locations in the state of Tamilnadu, India is reported. Qualitative analyses were carried out to determine the major and minor constituent minerals present in the samples based on the FTIR, XRD absorption peaks. This study also identified the minerals like quartz, asbestos, kaolinite, calcite, hematite, montmorillonite, nacrite and several other trace minerals in the air dust particles. The presents of quartz is mainly found in all the samples invariably. Hence the percentage of quartz and its crystalline nature were determined with the help of extinction co-efficient and crystallinity index respectively. The shape and size of the particulates are studied with SEM analysis.
The purpose of this SOP is to describe the methods used to collect indoor and outdoor air samples for the determination of selected volatile organic compounds (VOC's) using a pump to draw air through a Carbotrap Sampler. Volatile organic compounds (VOCs) present in the air are p...
Diagnosing AIRS Sampling with CloudSat Cloud Classes
NASA Technical Reports Server (NTRS)
Fetzer, Eric; Yue, Qing; Guillaume, Alexandre; Kahn, Brian
2011-01-01
AIRS yield and sampling vary with cloud state. Careful utilization of collocated multiple satellite sensors is necessary. Profile differences between AIRS and ECMWF model analyses indicate that AIRS has high sampling and excellent accuracy for certain meteorological conditions. Cloud-dependent sampling biases may have large impact on AIRS L2 and L3 data in climate research. MBL clouds / lower tropospheric stability relationship is one example. AIRS and CloudSat reveal a reasonable climatology in the MBL cloud regime despite limited sampling in stratocumulus. Thermodynamic parameters such as EIS derived from AIRS data map these cloud conditions successfully. We are working on characterizing AIRS scenes with mixed cloud types.
The objective of this procedure is to collect a representative sample of air containing volatile organic compound (VOC) contaminants present in an indoor environment using an evacuated canister, and to subsequently analyze the concentration of VOCs, as selected by EPA.
The purpose of this SOP is to describe methods for extracting and preparing an air sample consisting of a quartz fiber filter (Pallflex) and an XAD-2 cartridge for analysis of pesticides and polyaromatic hydrocarbons (PAHs). It covers the preparation of samples that are to be an...
Brebeck, Anne-Kathrin; Deussen, Andreas; Range, Ursula; Balestra, Costantino; Cleveland, Sinclair; Schipke, Jochen D
2018-03-01
Bubble formation during scuba diving might induce decompression sickness. This prospective randomised and double-blind study included 108 advanced recreational divers (38 females). Fifty-four pairs of divers, 1 breathing air and the other breathing nitrox28 undertook a standardised dive (24 ± 1 msw; 62 ± 5min) in the Red Sea. Venous gas bubbles were counted (Doppler) 30-<45 min (early) and 45-60 min (late) post-dive at jugular, subclavian and femoral sites. Only 7% (air) vs. 11% (air28®) (n.s.) were bubble-free after a dive. Independent of sampling time and breathing gas, there were more bubbles in the jugular than in the femoral vein. More bubbles were counted in the air-group than in the air28-group (pooled vein: early: 1845 vs. 948; P = 0.047, late: 1817 vs. 953; P = 0.088). The number of bubbles was sex-dependent. Lastly, 29% of female air divers but only 14% of male divers were bubble-free (P = 0.058). Air28® helps to reduce venous gas emboli in recreational divers. The bubble number depended on the breathing gas, sampling site and sex. Thus, both exact reporting the dive and in particular standardising sampling characteristics seem mandatory to compare results from different studies to further investigate the hitherto incoherent relation between inert gas bubbles and DCS.
Whyatt, Robin M; Barr, Dana B; Camann, David E; Kinney, Patrick L; Barr, John R; Andrews, Howard F; Hoepner, Lori A; Garfinkel, Robin; Hazi, Yair; Reyes, Andria; Ramirez, Judyth; Cosme, Yesenia; Perera, Frederica P
2003-01-01
We have measured 29 pesticides in plasma samples collected at birth between 1998 and 2001 from 230 mother and newborn pairs enrolled in the Columbia Center for Children's Environmental Health prospective cohort study. Our prior research has shown widespread pesticide use during pregnancy among this urban minority cohort from New York City. We also measured eight pesticides in 48-hr personal air samples collected from the mothers during pregnancy. The following seven pesticides were detected in 48-83% of plasma samples (range, 1-270 pg/g): the organophosphates chlorpyrifos and diazinon, the carbamates bendiocarb and 2-isopropoxyphenol (metabolite of propoxur), and the fungicides dicloran, phthalimide (metabolite of folpet and captan), and tetrahydrophthalimide (metabolite of captan and captafol). Maternal and cord plasma levels were similar and, except for phthalimide, were highly correlated (p < 0.001). Chlorpyrifos, diazinon, and propoxur were detected in 100% of personal air samples (range, 0.7-6,010 ng/m(3)). Diazinon and propoxur levels were significantly higher in the personal air of women reporting use of an exterminator, can sprays, and/or pest bombs during pregnancy compared with women reporting no pesticide use or use of lower toxicity methods only. A significant correlation was seen between personal air level of chlorpyrifos, diazinon, and propoxur and levels of these insecticides or their metabolites in plasma samples (maternal and/or cord, p < 0.05). The fungicide ortho-phenylphenol was also detected in 100% of air samples but was not measured in plasma. The remaining 22 pesticides were detected in 0-45% of air or plasma samples. Chlorpyrifos, diazinon, propoxur, and bendiocarb levels in air and/or plasma decreased significantly between 1998 and 2001. Findings indicate that pesticide exposures are frequent but decreasing and that the pesticides are readily transferred to the developing fetus during pregnancy. PMID:12727605
Biobriefcase aerosol collector
Bell, Perry M [Tracy, CA; Christian, Allen T [Madison, WI; Bailey, Christopher G [Pleasanton, CA; Willis, Ladona [Manteca, CA; Masquelier, Donald A [Tracy, CA; Nasarabadi, Shanavaz L [Livermore, CA
2009-09-22
A system for sampling air and collecting particles entrained in the air that potentially include bioagents. The system comprises providing a receiving surface, directing a liquid to the receiving surface and producing a liquid surface. Collecting samples of the air and directing the samples of air so that the samples of air with particles entrained in the air impact the liquid surface. The particles potentially including bioagents become captured in the liquid. The air with particles entrained in the air impacts the liquid surface with sufficient velocity to entrain the particles into the liquid but cause minor turbulence. The liquid surface has a surface tension and the collector samples the air and directs the air to the liquid surface so that the air with particles entrained in the air impacts the liquid surface with sufficient velocity to entrain the particles into the liquid, but cause minor turbulence on the surface resulting in insignificant evaporation of the liquid.
Development and testing of a portable wind sensitive directional air sampler
NASA Technical Reports Server (NTRS)
Deyo, J.; Toma, J.; King, R. B.
1975-01-01
A portable wind sensitive directional air sampler was developed as part of an air pollution source identification system. The system is designed to identify sources of air pollution based on the directional collection of field air samples and their analysis for TSP and trace element characteristics. Sources can be identified by analyzing the data on the basis of pattern recognition concepts. The unit, designated Air Scout, receives wind direction signals from an associated wind vane. Air samples are collected on filter slides using a standard high volume air sampler drawing air through a porting arrangement which tracks the wind direction and permits collection of discrete samples. A preset timer controls the length of time each filter is in the sampling position. At the conclusion of the sampling period a new filter is automatically moved into sampling position displacing the previous filter to a storage compartment. Thus the Air Scout may be set up at a field location, loaded with up to 12 filter slides, and left to acquire air samples automatically, according to the wind, at any timer interval desired from 1 to 30 hours.
Monitoring of Microscopic Filamentous Fungi in Indoor Air of Transplant Unit.
Holý, Ondřej; Matoušková, Ivanka; Kubátová, Alena; Hamal, Petr; Svobodová, Lucie; Jurásková, Eva; Raida, Luděk
2015-12-01
The aim of the study was to control the microbial contamination of indoor air monitored monthly at the Transplant Unit of the University Hospital Olomouc from August 2010 to July 2011. The unit is equipped with a three-stage air filtration system with HEPA filters. The MAS-100 air sampler (Merck, GER) was used. Twenty locations were singled out for the purposes of collecting a total of 720 samplings of the indoor air. Swabs of the HVAC diffusers at the sampling locations were always carried out after the sampling of the indoor air. In total, 480 samples of the indoor air were taken for Sabouraud chloramphenicol agar. In 11 cases (2.29%) the cultivation verified the presence of microscopic filamentous fungi. Only two cases involved the sanitary facilities of a patient isolation box; the other positive findings were from the facilities. The most frequent established genus was Aspergillus spp. (4x), followed by Trichoderma spp. (2x) and Penicillium spp. (2x), Paecilomyces spp., Eurotium spp., and Chrysonilia spp. (1x each). In 2 cases the cultivation established sterile aerial mycelium, unfortunately no further identification was possible. A total of 726 swabs of HVAC diffusers were collected (2 positive-0.28%). The study results demonstrated the efficacy of the HVAC equipment. With the continuing increase in the number of severely immunocompromised patients, hospitals are faced with the growing problem of invasive aspergillosis and other opportunistic infections. Preventive monitoring of microbial air contaminants is of major importance for the control of invasive aspergillosis. Copyright© by the National Institute of Public Health, Prague 2015.
Yan, Cheing-Tong; Chien, Hai-Ying
2012-07-13
In this study, a simple and novel one-step hollow-fiber supported liquid-phase sampling (HF-LPS) technique was developed for enriched sampling of gaseous toxic species prior to chemical analysis for workplace air monitoring. A lab-made apparatus designed with a gaseous sample generator and a microdialysis sampling cavity (for HF-LPS) was utilized and evaluated to simulate gaseous contaminant air for occupational workplace analysis. Gaseous phenol was selected as the model toxic species. A polyethersulfone hollow fiber dialysis module filled with ethylene glycol in the shell-side was applied as the absorption solvent to collect phenol from a gas flow through the tube-side, based on the concentration distribution of phenol between the absorption solvent and the gas flow. After sampling, 20 μL of the extractant was analyzed by high performance liquid chromatography with ultraviolet detection (HPLC-UV). Factors that influence the generation of gaseous standards and the HF-LPS were studied thoroughly. Results indicated that at 25 °C the phenol (2000 μg/mL) standard solution injected at 15-μL/min can be vaporized into sampling cavity under nitrogen flow at 780 mL/min, to generate gaseous phenol with concentration approximate to twice the permissible exposure limit. Sampling at 37.3 mL/min for 30 min can meet the requirement of the workplace air monitoring. The phenol in air ranged between 0.7 and 10 cm³/m³ (shows excellent linearity) with recovery between 98.1 and 104.1%. The proposed method was identified as a one-step sampling for workplace monitoring with advantages of convenience, rapidity, sensitivity, and usage of less-toxic solvent. Copyright © 2012 Elsevier B.V. All rights reserved.
Synthetic turf field investigation in Connecticut.
Simcox, Nancy J; Bracker, Anne; Ginsberg, Gary; Toal, Brian; Golembiewski, Brian; Kurland, Tara; Hedman, Curtis
2011-01-01
The primary purpose of this study was to characterize the concentrations of volatile organic compounds (VOC), semivolatile organic compounds (SVOC), rubber-related chemicals such as benzothiazole (BZT) and nitrosamine, and particulate matter (PM(10)) in air at synthetic turf crumb rubber fields. Both new and older fields were evaluated under conditions of active use. Three types of fields were targeted: four outdoor crumb rubber fields, one indoor facility with crumb rubber turf, and an outdoor natural grass field. Background samples were collected at each field on grass. Personal air sampling was conducted for VOC, BZT, nitrosamines, and other chemicals. Stationary air samples were collected at different heights to assess the vertical profile of release. Air monitoring for PM(10) was conducted at one height. Bulk samples of turf grass and crumb rubber were analyzed, and meteorological data were recorded. Results showed that personal concentrations were higher than stationary concentrations and were higher on turf than in background samples for certain VOC. In some cases, personal VOC concentrations from natural grass fields were as high as those on turf. Naphthalene, BZT, and butylated hydroxytoluene (BHT) were detected in greater concentration at the indoor field compared to the outdoor fields. Nitrosamine air levels were below reporting levels. PM(10) air concentrations were not different between on-field and upwind locations. All bulk lead (Pb) samples were below the public health target of 400 ppm. More research is needed to better understand air quality at indoor facilities. These field investigation data were incorporated into a separate human health risk assessment.
Su, Yushan; Hung, Hayley
2010-11-01
Measurements of semi-volatile organic chemicals (SVOCs) were compared among 21 laboratories from 7 countries through the analysis of standards, a blind sample, an air extract, and an atmospheric dust sample. Measurement accuracy strongly depended on analytes, laboratories, and types of standards and samples. Intra-laboratory precision was generally good with relative standard deviations (RSDs) of triplicate injections <10% and with median differences of duplicate samples between 2.1 and 22%. Inter-laboratory variability, measured by RSDs of all measurements, was in the range of 2.8-58% in analyzing standards, and 6.9-190% in analyzing blind sample and air extract. Inter-laboratory precision was poorer when samples were subject to cleanup processes, or when SVOCs were quantified at low concentrations. In general, inter-laboratory differences up to a factor of 2 can be expected to analyze atmospheric SVOCs. When comparing air measurements from different laboratories, caution should be exercised if the data variability is less than the inter-laboratory differences. 2010. Published by Elsevier Ltd. All rights reserved.
Conway, Thomas [NOAA Climate Monitoring and Diagnostics Laboratory, Boulder, CO (USA); Tans, Pieter [NOAA Climate Monitoring and Diagnostics Laboratory, Boulder, CO (USA)
2009-01-01
The National Oceanic and Atmospheric Administration's Climate Monitoring and Diagnostics Laboratory (NOAA/CMDL) has measured CO2 in air samples collected weekly at a global network of sites since the late 1960s. Atmospheric CO2 mixing ratios reported in these files were measured by a nondispersive infrared absorption technique in air samples collected in glass flasks. All CMDL flask samples are measured relative to standards traceable to the World Meteorological Organization (WMO) CO2 mole fraction scale. These measurements constitute the most geographically extensive, carefully calibrated, internally consistent atmospheric CO2 data set available and are essential for studies aimed at better understanding the global carbon cycle budget.
Indoor air quality in urban and rural kindergartens: short-term studies in Silesia, Poland.
Błaszczyk, Ewa; Rogula-Kozłowska, Wioletta; Klejnowski, Krzysztof; Kubiesa, Piotr; Fulara, Izabela; Mielżyńska-Švach, Danuta
2017-01-01
More than 80% of people living in urban areas who monitor air pollution are exposed to air quality levels that exceed limits defined by the World Health Organization (WHO). Although all regions of the world are affected, populations in low-income cities are the most impacted. According to average annual levels of fine particulate matter (PM2.5, ambient particles with aerodynamic diameter of 2.5 μm or less) presented in the urban air quality database issued by WHO in 2016, as many as 33 Polish cities are among the 50 most polluted cities in the European Union (EU), with Silesian cities topping the list. The aim of this study was to characterize the indoor air quality in Silesian kindergartens based on the concentrations of gaseous compounds (SO 2 , NO 2 ), PM2.5, and the sum of 15 PM2.5-bound polycyclic aromatic hydrocarbons (PAHs), including PM2.5-bound benzo(a)pyrene (BaP), as well as the mutagenic activity of PM2.5 organic extracts in Salmonella assay (strains: TA98, YG1024). The assessment of the indoor air quality was performed taking into consideration the pollution of the atmospheric air (outdoor). I/O ratios (indoor/outdoor concentration) for each investigated parameter were also calculated. Twenty-four-hour samples of PM2.5, SO 2 , and NO 2 were collected during spring in two sites in southern Poland (Silesia), representing urban and rural areas. Indoor samples were taken in naturally ventilated kindergartens. At the same time, in the vicinity of the kindergarten buildings, the collection of outdoor samples of PM2.5, SO 2 , and NO 2 was carried out. The content of BaP and the sum of 15 studied PAHs was determined in each 24-h sample of PM2.5 (indoor and outdoor). In the urban site, statistically lower concentrations of SO 2 and NO 2 were detected indoors compared to outdoors, whereas in the rural site, such a relationship was observed only for NO 2 . No statistically significant differences in the concentrations of PM2.5, PM2.5-bound BaP, and Σ15 PAHs in kindergartens (indoor) versus atmospheric (outdoor) air in the two studied areas were identified. Mutagenic effect of indoor PM2.5 samples was twice as low as in outdoor samples. The I/O ratios indicated that all studied air pollutants in the urban kindergarten originated from the ambient air. In the rural site concentrations of SO 2 , PM2.5 and BaP in the kindergarten were influenced by internal sources (gas and coal stoves).
Microbial communities in air and wine of a winery at two consecutive vintages.
Pérez-Martín, Fátima; Seseña, Susana; Fernández-González, Mónica; Arévalo, María; Palop, María Llanos
2014-11-03
The aim of this study was to assess, both quantitatively and qualitatively, the populations of lactic acid bacteria (LAB) and yeasts in air and wine of a winery, in order to evaluate the possible exchange of microorganisms between them. Samples were taken in a winery located in Castilla-La Mancha (Spain) during the winemaking period of two consecutive vintages (2011 and 2012). The microbial composition was determined by using both a culture-dependent method and a culture-independent method, PCR-denaturing gradient gel electrophoresis (PCR-DGGE). In addition, genetic characterization of isolates from plates was carried out. A high diversity of species was detected in air and wine samples from both vintages. Leuconostoc mesenteroides was the predominant lactic acid bacteria in air from both vintages while Oenococcus oeni was the predominant in wine. Saccharomyces cerevisiae was the most frequently isolated yeast in both air and wine. Typing of O. oeni and S. cerevisiae isolates from air and wine samples showed the presence of coincident genotypes in both samples, that would confirm the exchange of microorganisms between the two environments, air and wine, and furthermore some of these genotypes were also found at samples taken at different vintages, indicating that they would remain in the winery. The results display the influence of the activity taking place in the winery and the moment of fermentation of the wines in tanks, on the microorganisms present in the air and the role of the air for the dispersal of microorganisms within the winery. Copyright © 2014 Elsevier B.V. All rights reserved.
As part of the Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS) investigating the respiratory health impacts of traffic-related air pollutants on asthmatic children in Detroit, Michigan, residential dust samples were collected to quantify mold exposure. Sett...
The primary objective of this study is to characterize the genotoxic potential of the ambient air aerosols collected within an air shed impacted primarily by wood smoke and automotive emissions. The study also examines the relative merits of a microsuspension assay and the standa...
Suryawanshi, Shalini; Chauhan, Amit Singh; Verma, Ritika; Gupta, Tarun
2016-11-01
There is a growing concern regarding the adverse health effects due to indoor air pollution in developing countries including India. Hence, it becomes important to study the causes and sources of indoor air pollutants. This study presents the indoor concentrations of PM0.6 (particles with aerodynamic diameter less than 0.6μm) and identifies sources leading to indoor air pollution. Indoor air samples were collected at IIT Kanpur campus. Ninety-eight PM0.6 samples were collected during November 2013 to September 2014. PM0.6 concentration was measured using a single stage impactor type PM0.6 sampler. The average PM0.6 concentration indoor was about 94.44μg/m(3). Samples collected were then analysed for metal concentrations using ICP-OES (Inductively Coupled Plasma - Optical Emission Spectrometer). Eight metals Ba, Ca, Cr, Cu, Fe, Mg, Ni and Pb were quantified from PM samples using ICP-OES. Positive Matrix Factorization (PMF) was used for source apportionment of indoor air pollution. PMF is a factor analysis tool which helps in resolving the profile and contribution of the sources from an unknown mixture. Five possible sources of indoor pollutants were identified by factor analysis - (1) Coal combustion (21.8%) (2) Tobacco smoking (9.8%) (3) Wall dust (25.7%) (4) Soil particles (17.5%) (5) Wooden furniture/paper products (25.2%). Copyright © 2016 Elsevier B.V. All rights reserved.
Air Quality and Road Emission Results for Fort Stewart, Georgia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kirkham, Randy R.; Driver, Crystal J.; Chamness, Mickie A.
2004-02-02
The Directorate of Public Works Environmental & Natural Resources Division (Fort Stewart /Hunter Army Airfield) contracted with the Pacific Northwest National Laboratory (PNNL) to monitor particulate matter (PM) concentrations on Fort Stewart, Georgia. The purpose of this investigation was to establish a PM sampling network using monitoring equipment typically used in U.S. Environmental Protection Agency (EPA) ''saturation sampling'', to determine air quality on the installation. In this initial study, the emphasis was on training-generated PM, not receptor PM loading. The majority of PM samples were 24-hr filter-based samples with sampling frequency ranging from every other day, to once every sixmore » days synchronized with the EPA 6th day national sampling schedule. Eight measurement sites were established and used to determine spatial variability in PM concentrations and evaluate whether fluctuations in PM appear to result from training activities and forest management practices on the installation. Data collected to date indicate the average installation PM2.5 concentration is lower than that of nearby urban Savannah, Georgia. At three sites near the installation perimeter, analyses to segregate PM concentrations by direction of air flow across the installation boundary indicate that air (below 80 ft) leaving the installation contains less PM2.5 than that entering the installation. This is reinforced by the observation that air near the ground is cleaner on average than the air at the top of the canopy.« less
Adaptive Sampling for Urban Air Quality through Participatory Sensing
Zeng, Yuanyuan; Xiang, Kai
2017-01-01
Air pollution is one of the major problems of the modern world. The popularization and powerful functions of smartphone applications enable people to participate in urban sensing to better know about the air problems surrounding them. Data sampling is one of the most important problems that affect the sensing performance. In this paper, we propose an Adaptive Sampling Scheme for Urban Air Quality (AS-air) through participatory sensing. Firstly, we propose to find the pattern rules of air quality according to the historical data contributed by participants based on Apriori algorithm. Based on it, we predict the on-line air quality and use it to accelerate the learning process to choose and adapt the sampling parameter based on Q-learning. The evaluation results show that AS-air provides an energy-efficient sampling strategy, which is adaptive toward the varied outside air environment with good sampling efficiency. PMID:29099766
Sampling for Air Chemical Emissions from the Life Sciences Laboratory II
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ballinger, Marcel Y.; Lindberg, Michael J.
Sampling for air chemical emissions from the Life Science Laboratory II (LSL-II) ventilation stack was performed in an effort to determine potential exposure of maintenance staff to laboratory exhaust on the building roof. The concern about worker exposure was raised in December 2015 and several activities were performed to assist in estimating exposure concentrations. Data quality objectives were developed to determine the need for and scope and parameters of a sampling campaign to measure chemical emissions from research and development activities to the outside air. The activities provided data on temporal variation of air chemical concentrations and a basis formore » evaluating calculated emissions. Sampling for air chemical emissions was performed in the LSL-II ventilation stack over the 6-week period from July 26 to September 1, 2016. A total of 12 sampling events were carried out using 16 sample media. Resulting analysis provided concentration data on 49 analytes. All results were below occupational exposure limits and most results were below detection limits. When compared to calculated emissions, only 5 of the 49 chemicals had measured concentrations greater than predicted. This sampling effort will inform other study components to develop a more complete picture of a worker’s potential exposure from LSL-II rooftop activities. Mixing studies were conducted to inform spatial variation in concentrations at other rooftop locations and can be used in conjunction with these results to provide temporal variations in concentrations for estimating the potential exposure to workers working in and around the LSL-II stack.« less
The role of open-air inhalatoria in the air quality improvement in spa towns.
Burkowska-But, Aleksandra; Kalwasińska, Agnieszka; Brzezinska, Maria Swiontek
2014-08-01
The present study was aimed at evaluating microbiological contamination of air in Ciechocinek and Inowrocław - Polish lowland spa towns. Additionally, the impact of open-air inhalatoria on the quality of air was evaluated. Air samples were collected seasonally in the urban areas, in the recreation areas and in the vicinity of inhalatoria in both towns using impaction. The numbers of mesophilic bacteria, staphylococci, hemolytic bacteria and actinomycetes were determined on media according to the Polish Standard PN-86/Z-04111/02. The number of moulds was determined on media according to the Polish Standard PN-86/Z-04111/03. While the highest numbers of microorganisms were noted at the sites located in the urban areas, the lowest numbers were noted in the vicinity of the open-air inhalatoria. In all the investigated air samples the values of bioaerosol concentrations were below the recommended TLVs (≤ 5000 CFU×m(-3) for both bacteria and fungi in outdoor environments). Location of the sampling site was invariably a decisive factor in determining the number of microorganisms in the air. The aerosol which is formed in the open-air inhalatoria has a positive influence on microbiological air quality. Owing to a unique microclimate and low air contamination, Ciechocinek and Inowrocław comply with all necessary requirements set for health resorts specializing in treating upper respiratory tract infections.
Agodi, A; Auxilia, F; Barchitta, M; Cristina, M L; D'Alessandro, D; Mura, I; Nobile, M; Pasquarella, C
2015-07-01
Recent studies have shown a higher rate of surgical site infections in hip prosthesis implantation using unidirectional airflow ventilation compared with turbulent ventilation. However, these studies did not measure the air microbial quality of operating theatres (OTs), and assumed it to be compliant with the recommended standards for this ventilation technique. To evaluate airborne microbial contamination in OTs during hip and knee replacement surgery, and compare the findings with values recommended for joint replacement surgery. Air samplings were performed in 28 OTs supplied with unidirectional, turbulent and mixed airflow ventilation. Samples were collected using passive sampling to determine the index of microbial air contamination (IMA). Active sampling was also performed in some of the OTs. The average number of people in the OT and the number of door openings during the sampling period were recorded. In total, 1228 elective prosthesis procedures (60.1% hip and 39.9% knee) were included in this study. Of passive samplings performed during surgical activity in unidirectional airflow ventilation OTs (U-OTs) and mixed airflow OTs (M-OTs), 58.9% and 87.6% had IMA values >2, respectively. Of samplings performed during surgical activity in turbulent airflow OTs (T-OTs) and in turbulent airflow OTs with the surgical team wearing Steri-Shield Turbo Helmets (TH-OTs), 8.6% and 60% had IMA values ≤ 2, respectively. Positive correlation was found between IMA values and the number of people in the OT and the number of door openings (P < 0.001). In addition, correlation was found between active and passive sampling (P < 0.001). These findings challenge the belief that unidirectional systems always provide acceptable airborne bacterial counts. Copyright © 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
Influence of air quality on the composition of microbial pathogens in fresh rainwater.
Kaushik, Rajni; Balasubramanian, Rajasekhar; de la Cruz, Armah A
2012-04-01
In this study, the microbiological quality of fresh rainwater was assessed from 50 rain events under tropical weather conditions for a year. The levels of four major opportunistic waterborne pathogens, namely, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Aeromonas hydrophila, in rainwater samples were quantified by using a robust and sensitive quantitative PCR (qPCR) method. Of the 50 rainwater samples, 25 were found to be positive for at least one pathogen: 21 for E. coli, 16 for P. aeruginosa, 6 for K. pneumoniae, and 1 for A. hydrophila. In addition to the microbiological assessment of rainwater samples, we also studied the influence of prevailing air quality on the microbial quality of rainwater over the sampling period. A significant change in the diversity and relative abundance of the basic microbial indicator organisms in rainwater was observed during a major regional air pollution episode in Southeast Asia due to biomass-burning emissions.
Determination of tricresyl phosphate air contamination in aircraft.
Denola, G; Hanhela, P J; Mazurek, W
2011-08-01
Monitoring of tricresyl phosphate (TCP) contamination of cockpit air was undertaken in three types of military aircraft [fighter trainer (FT), fighter bomber (FB), and cargo transport (CT) aircraft]. The aircraft had a previous history of pilot complaints about cockpit air contamination suspected to originate from the engine bleed air supply through the entry of aircraft turbine engine oil (ATO) into the engine compressor. Air samples were collected in flight and on the ground during engine runs using sorbent tubes packed with Porapak Q and cellulose filters. A total of 78 air samples were analysed, from 46 different aircraft, and 48 samples were found to be below the limit of detection. Nine incidents of smoke/odour were identified during the study. The concentrations of toxic o-cresyl phosphate isomers were below the level of detection in all samples. The highest total TCP concentration was 51.3 μg m(-3), while most were generally found to be <5 μg m(-3) compared with the 8-h time-weighted average exposure limit of 100 μg m(-3) for tri-o-cresyl phosphate. The highest concentrations were found at high engine power. Although TCP contamination of cabin/cockpit air has been the subject of much concern in aviation, quantitative data are sparse.
Eight Year Climatologies from Observational (AIRS) and Model (MERRA) Data
NASA Technical Reports Server (NTRS)
Hearty, Thomas; Savtchenko, Andrey; Won, Young-In; Theobalk, Mike; Vollmer, Bruce; Manning, Evan; Smith, Peter; Ostrenga, Dana; Leptoukh, Greg
2010-01-01
We examine climatologies derived from eight years of temperature, water vapor, cloud, and trace gas observations made by the Atmospheric Infrared Sounder (AIRS) instrument flying on the Aqua satellite and compare them to similar climatologies constructed with data from a global assimilation model, the Modern Era Retrospective-Analysis for Research and Applications (MERRA). We use the AIRS climatologies to examine anomalies and trends in the AIRS data record. Since sampling can be an issue for infrared satellites in low earth orbit, we also use the MERRA data to examine the AIRS sampling biases. By sampling the MERRA data at the AIRS space-time locations both with and without the AIRS quality control we estimate the sampling bias of the AIRS climatology and the atmospheric conditions where AIRS has a lower sampling rate. While the AIRS temperature and water vapor sampling biases are small at low latitudes, they can be more than a few degrees in temperature or 10 percent in water vapor at higher latitudes. The largest sampling biases are over desert. The AIRS and MERRA data are available from the Goddard Earth Sciences Data and Information Services Center (GES DISC). The AIRS climatologies we used are available for analysis with the GIOVANNI data exploration tool. (see, http://disc.gsfc.nasa.gov).
NASA Astrophysics Data System (ADS)
Sadiq, M.; Mian, A. A.
Air particulates, both the total suspended (TSP) and inhalable (PM 10, smaller than 10 microns in size), were collected during and after the Kuwait oil fires (from March 1991 to July 1992) using Hi-Vol samplers. These samples were wet-digested at 120°C in an aqua regia and perchloric acids mixture for 3 h. Air particulate samples collected in 1982 at the same location were prepared similarly. Concentrations of nickel and vanadium were determined in the aliquot samples using an inductively coupled argon plasma analyser (ICAP). The monthly mean concentrations of nickel and vanadium, on volume basis, increased rapidly from March to June and decreased sharply during July-August in 1991. The minimum mean concentrations of these elements were found in the particulate samples collected in December 1991 which gradually increased through May 1992. Like 1991, nickel and vanadium concentrations in the air particulates spiked in June and decreased again in July 1992. This distribution pattern of nickel and vanadium concentrations was similar to that of the predominant wind from the north (Kuwait). In general, concentrations of these elements were higher in the air particulates collected during April-July 1991 as compared with those collected in 1992 during the same period. The TSPs contained higher concentrations of nickel and vanadium than those found in the PM 10 samples. However, this trend was reversed when concentrations of nickel and vanadium, on were expressed on particulate weight basis. The monthly mean concentrations of nickel and vanadium, on weight basis, decreased gradually through 1991 and increased slightly from March to July 1992. Concentrations of these elements were significantly higher in the air particulate samples collected in 1991 than those samples collected during 1982 at the same location. The data of this study suggest a contribution of the Kuwait oil fires in elevating nickel and vanadium concentrations in the air particulates at Dhahran during April-July 1991. Concentrations of these elements were largely below their proposed limits in the ambient air (for nickel-50 μg m -3, air; for vanadium—1 μg m -3 air). It is, therefore, anticipated that concentrations of nickel and vanadium in the air particulate samples were not a health concern during Kuwait oil fires at Dhahran, Saudi Arabia.
Isolating and identifying atmospheric ice-nucleating aerosols: a new technique
NASA Astrophysics Data System (ADS)
Kreidenweis, S. M.; Chen, Y.; Rogers, D. C.; DeMott, P. J.
Laboratory studies examined two key aspects of the performance of a continuous-flow diffusion chamber (CFD) instrument that detects ice nuclei (IN) concentrations in air samples: separating IN from non-IN, and collecting IN aerosols to determine chemical composition. In the first study, submicron AgI IN particles were mixed in a sample stream with submicron non-IN salt particles, and the sample stream was processed in the CFD at -19°C and 23% supersaturation with respect to ice. Examination of the residual particles from crystals nucleated in the CFD confirmed that only AgI particles served as IN in the mixed stream. The second study applied this technique to separate and analyze IN and non-IN particles in a natural air sample. Energy-dispersive X-ray analyses (EDS) of the elemental composition of selected particles from the IN and non-IN fractions in ambient air showed chemical differences: Si and Ca were present in both, but S, Fe and K were also detected in the non-IN fraction.
NASA Astrophysics Data System (ADS)
Arp, Hans Peter H.; Goss, Kai-Uwe
Due to the apparent environmental omnipresence of perfluorocarboxylic acids (PFAs), an increasing number of researchers are investigating their ambient particle- and gas-phase concentrations. Typically this is done using a high-volume air sampler equipped with Quartz Fiber Filters (QFFs) or Glass Fiber Filters (GFFs) to sample the particle-bound PFAs and downstream sorbents to sample the gas-phase PFAs. This study reports that at trace, ambient concentrations gas-phase PFAs sorb to QFFs and GFFs irreversibly and hardly pass through these filters to the downstream sorbents. As a consequence, it is not possible to distinguish between particle- and gas-phase concentrations, or to distinguish concentrations on different particle size fractions, unless precautions are taken. Failure to take such precautions could have already caused reported data to be misinterpreted. Here it is also reported that deactivating QFFs and GFFs with a silylating agent renders them suitable for sampling PFAs. Based on the presented study, a series of recommendations for air-sampling PFAs are provided.
Koong, Heng Nung; Khoo, Deborah; Higbee, Cheryl; Travers, Mark; Hyland, Andrew; Cummings, K Michael; Dresler, Carolyn
2009-03-01
A local study completed in Singapore, which was part of an international multi-country study that aims to develop a global assessment of exposure to second-hand smoke in indoor workplaces, gathered data regarding the indoor air quality of public areas. It was hypothesised that air would be less polluted in non-smoking venues compared to places where smoking occurred. A TSI SidePak AM510 Personal Aerosol Monitor was used to sample and record the levels of respirable suspended particles (RSP) in the air. A broad range of venues were sampled in Singapore. The primary goal of data analysis was to assess the difference in the average levels of RSP in smoke-free and non smoke-free venues. Data was assessed at 3 levels: (a) the mean RSP across all venues sampled compared with the mean levels of smoke-free and non smoke-free venues, (b) levels in venues where smoking occurred compared with similar venues in Ireland, and (c) comparison between smoke-free and non smoke-free areas according to the type of venue. Statistical significance was assessed using the Mann-Whitney U-test. The level of indoor air pollution was 96% lower in smoke-free venues compared to non smoke-free venues. Averaged across each type of venue, the lowest levels of indoor air pollution were found in restaurants (17 microg/m3) and the highest in bars (622 microg/m3); both well above the US EPA Air Quality Index hazardous level of >or=251 ug/m3. This study demonstrates that workers and patrons are exposed to harmful levels of a known carcinogen and toxin. Policies that prohibit smoking in public areas dramatically reduce exposure and improve worker and patron health.
Balderrama-Carmona, Ana Paola; Gortáres-Moroyoqui, Pablo; Álvarez-Valencia, Luis Humberto; Castro-Espinoza, Luciano; Mondaca-Fernández, Iram; Balderas-Cortés, José de Jesús; Chaidez-Quiroz, Cristóbal; Meza-Montenegro, María Mercedes
2014-09-01
Cryptosporidium oocysts and Giardia cysts can be transmitted by the fecal-oral route and may cause gastrointestinal parasitic zoonoses. These zoonoses are common in rural zones due to the parasites being harbored in fecally contaminated soil. This study assessed the risk of illness (giardiasis and cryptosporidiosis) from inhaling and/or ingesting soil and/or airborne dust in Potam, Mexico. To assess the risk of infection, Quantitative Microbial Risk Assessment (QMRA) was employed, with the following steps: (1) hazard identification, (2) hazard exposure, (3) dose-response, and (4) risk characterization. Cryptosporidium oocysts and Giardia cysts were observed in 52% and 57%, respectively, of total soil samples (n=21), and in 60% and 80%, respectively, of air samples (n=12). The calculated annual risks were higher than 9.9 × 10(-1) for both parasites in both types of sample. Soil and air inhalation and/or ingestion are important vehicles for these parasites. To our knowledge, the results obtained in the present study represent the first QMRAs for cryptosporidiosis and giardiasis due to soil and air inhalation/ingestion in Mexico. In addition, this is the first evidence of the microbial air quality around these parasites in rural zones. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.
Evaluation of the release of dioxins and PCBs during kiln-firing of ball clay.
Broadwater, Kendra; Meeker, John D; Luksemburg, William; Maier, Martha; Garabrant, David; Demond, Avery; Franzblau, Alfred
2014-01-01
Ball clay is known to be naturally contaminated with high levels of polychlorinated di-benzo-p-dioxins (PCDDs). This study evaluated the potential for PCDD, polychlorinated dibenzofuran (PCDF) and polychlorinated biphenyl (PCB) release during the kiln firing of ball clay in an art studio. Toxic equivalence (TEQ) were calculated using World Health Organization (WHO) 2005 toxic equivalence factors (TEF) and congener concentrations. Ten bags of commercial ball clay were found to have an average TEQ of 1,370 nanograms/kilogram (ng kg(-1)) dry weight (dw), almost exclusively due to PCDDs (99.98% of TEQ). After firing, none of the 29 dioxin-like analytes was measured above the limits of detection (LOD) in the clay samples. Air samples were taken during firings using both low-flow and high-flow air samplers. Few low-flow air samples contained measurable levels of dioxin congeners above the LOD. The mean TEQ in the high volume air samples ranged from 0.07 pg m(-3) to 0.21 pg m(-3) when firing ball clay, and was 0.11 pg m(-3) when no clay was fired. These concentrations are within the range measured in typical residences and well-controlled industrial settings. The congener profiles in the high-flow air samples differed from the unfired clay; the air samples had a considerable contribution to the TEQ from PCDFs and PCBs. Given that the TEQs of all air samples were very low and the profiles differed from the unfired clay, it is likely that the PCDDs in dry ball clay were destroyed during kiln firing. These results suggest that inhalation of volatilized dioxins during kiln firing of dry ball clay is an unlikely source of exposure for vocational and art ceramicists. Copyright © 2013 Elsevier Ltd. All rights reserved.
A study of atmospheric mixing of trace gases by aerial sampling with a multi-rotor drone
NASA Astrophysics Data System (ADS)
Chang, Chih-Chung; Chang, Chih-Yuan; Wang, Jia-Lin; Lin, Ming-Ren; Ou-Yang, Chang-Feng; Pan, Hsiang-Hsu; Chen, Yen-Chen
2018-07-01
We exploited a novel sampling vehicle, a multi-rotor drone carrying a remote-controlled whole air sampling device, to collect aerial samples with high sample integrity and preservation conditions. An array of 106 volatile organic compounds (VOCs), CO, CH4, and CO2 were analyzed and compared between the aerial samples (300-m height) and the ground-level samples in pairs to inspect for vertical mixing of the trace gases at a coastal site under three different meteorological conditions of local circulation, frontal passage, and high-pressure peripheral circulation. A rather homogeneous composition was observed for the sample pairs immediately after the frontal passage, indicating a well-mixed condition below 300 m. In contrast, inhomogeneous mixing was observed for the sample pairs under the other two conditions (local circulation and high-pressure peripheral circulation), suggesting different layers of air masses. Furthermore, information of unique source markers, composition profiles, and lifetimes of compounds were used to differentiate the origins of the air masses aloft and at the surface to substantiate the observed inhomogeneity. The study demonstrates that, with the availability of the near-surface aerial sampling coupling with in-laboratory analysis, detailed compositions of trace gases can now be readily obtained with superior data quality. Based on the distinctive chemical compositions, the sources, transport, and atmospheric mixing of the airborne pollutants in the near-surface atmosphere can be better studied and understood.
Friese, Anika; Klees, Sylvia; Tenhagen, Bernd A.; Fetsch, Alexandra; Rösler, Uwe; Hartung, Jörg
2012-01-01
During 1 year, samples were taken on 4 days, one sample in each season, from pigs, the floor, and the air inside pig barns and from the ambient air and soil at different distances outside six commercial livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA)-positive pig barns in the north and east of Germany. LA-MRSA was isolated from animals, floor, and air samples in the barn, showing a range of airborne LA-MRSA between 6 and 3,619 CFU/m3 (median, 151 CFU/m3). Downwind of the barns, LA-MRSA was detected in low concentrations (11 to 14 CFU/m3) at distances of 50 and 150 m; all upwind air samples were negative. In contrast, LA-MRSA was found on soil surfaces at distances of 50, 150, and 300 m downwind from all barns, but no statistical differences could be observed between the proportions of positive soil surface samples at the three different distances. Upwind of the barns, positive soil surface samples were found only sporadically. Significantly more positive LA-MRSA samples were found in summer than in the other seasons both in air and soil samples upwind and downwind of the pig barns. spa typing was used to confirm the identity of LA-MRSA types found inside and outside the barns. The results show that there is regular airborne LA-MRSA transmission and deposition, which are strongly influenced by wind direction and season, of up to at least 300 m around positive pig barns. The described boot sampling method seems suitable to characterize the contamination of the vicinity of LA-MRSA-positive pig barns by the airborne route. PMID:22685139
Schulz, Jochen; Friese, Anika; Klees, Sylvia; Tenhagen, Bernd A; Fetsch, Alexandra; Rösler, Uwe; Hartung, Jörg
2012-08-01
During 1 year, samples were taken on 4 days, one sample in each season, from pigs, the floor, and the air inside pig barns and from the ambient air and soil at different distances outside six commercial livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA)-positive pig barns in the north and east of Germany. LA-MRSA was isolated from animals, floor, and air samples in the barn, showing a range of airborne LA-MRSA between 6 and 3,619 CFU/m(3) (median, 151 CFU/m(3)). Downwind of the barns, LA-MRSA was detected in low concentrations (11 to 14 CFU/m(3)) at distances of 50 and 150 m; all upwind air samples were negative. In contrast, LA-MRSA was found on soil surfaces at distances of 50, 150, and 300 m downwind from all barns, but no statistical differences could be observed between the proportions of positive soil surface samples at the three different distances. Upwind of the barns, positive soil surface samples were found only sporadically. Significantly more positive LA-MRSA samples were found in summer than in the other seasons both in air and soil samples upwind and downwind of the pig barns. spa typing was used to confirm the identity of LA-MRSA types found inside and outside the barns. The results show that there is regular airborne LA-MRSA transmission and deposition, which are strongly influenced by wind direction and season, of up to at least 300 m around positive pig barns. The described boot sampling method seems suitable to characterize the contamination of the vicinity of LA-MRSA-positive pig barns by the airborne route.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Monroy, G.J. Keene, F.E.
A study to address Ambos (Both) Nogales' air quality concerns was conducted by the Arizona Department of Environmental Quality (ADEQ), in conjunction with Mexico's Secretaria de Medio Ambiente, Recursos Naturales y Pesca (SEMARNAP), from 1994 to 1998. The study, which is part of the US-Mexico Border XXI Program, consisted of the following tasks: (1) air sampling/monitoring; (2) emissions inventory; (3) meteorological modeling; and, (4) health risk assessment. The following types of samples were collected: particulate matter (PM); volatile organic compounds; semi-volatile organic compounds; and aldehydes. All samples were collected for a 24-hour period; every sixth day during the warm monthsmore » (April--September), and every third day during the cold months (October--March). There were a total of six sampling stations; three on each side of the border. PM samples were collected at all six sites, while samples for Hazardous Air Pollutants (HAPs) were collected at four of those sites. Sample analyses were performed at the Desert Research Institute (DRI) in Reno, Nevada. Furthermore, four of the sites were outfitted with meteorological equipment, in order to gather data on wind speed and direction. PM and meteorological data are still being collected at two sampling sites, one in Arizona and one in Sonora. An emissions inventory of point, mobile and area sources for the Ambos Nogales area (12 x 19 km. domain), was developed following completion of the sampling effort. In order to accomplish this task, ADEQ contracted the services of RADIAN International and Powers Engineering; which in turn enlisted the services of Heuristica Ambiental of Hermosillo, Sonora. This task was completed in July, 1997. Vehicular emissions were found to be one of the main contributors of air emissions in the Ambos Nogales area. The third task of this project consisted developing meteorological models of the study area.« less
ERIC Educational Resources Information Center
Safara, Maryam; Ghasemi, Pejman
2017-01-01
The aim of this study was to evaluate the efficacy of yoga on spiritual intelligence in air traffic controllers in Tehran flight control center. This was a quasi-experimental research and the study population includes all air traffic controllers in Tehran flight control center. The sample consisted of 40 people of the study population that were…
Are We Biologically Safe with Snow Precipitation? A Case Study in Beijing
Shen, Fangxia; Yao, Maosheng
2013-01-01
In this study, the bacterial and fungal abundances, diversities, conductance levels as well as total organic carbon (TOC) were investigated in the snow samples collected from five different snow occurrences in Beijing between January and March, 2010. The collected snow samples were melted and cultured at three different temperatures (4, 26 and 37°C). The culturable bacterial concentrations were manually counted and the resulting colony forming units (CFUs) at 26°C were further studied using V3 region of 16 S rRNA gene-targeted polymerase chain reaction -denaturing gradient gel electrophoresis (PCR-DGGE). The clone library was constructed after the liquid culturing of snow samples at 26°C. And microscopic method was employed to investigate the fungal diversity in the samples. In addition, outdoor air samples were also collected using mixed cellulose ester (MCE) filters and compared with snow samples with respect to described characteristics. The results revealed that snow samples had bacterial concentrations as much as 16000 CFU/ml for those cultured at 26°C, and the conductance levels ranged from 5.6×10−6 to 2.4×10−5 S. PCR-DGGE, sequencing and microscopic analysis revealed remarkable bacterial and fungal diversity differences between the snow samples and the outdoor air samples. In addition, DGGE banding profiles for the snow samples collected were also shown distinctly different from one another. Absent from the outdoor air, certain human, plant, and insect fungal pathogens were found in the snow samples. By calculation, culturable bacteria accounted for an average of 3.38% (±1.96%) of TOC for the snow samples, and 0.01% for that of outdoor air samples. The results here suggest that snow precipitations are important sources of fungal pathogens and ice nucleators, thus could affect local climate, human health and agriculture security. PMID:23762327
Are we biologically safe with snow precipitation? A case study in beijing.
Shen, Fangxia; Yao, Maosheng
2013-01-01
In this study, the bacterial and fungal abundances, diversities, conductance levels as well as total organic carbon (TOC) were investigated in the snow samples collected from five different snow occurrences in Beijing between January and March, 2010. The collected snow samples were melted and cultured at three different temperatures (4, 26 and 37°C). The culturable bacterial concentrations were manually counted and the resulting colony forming units (CFUs) at 26°C were further studied using V3 region of 16 S rRNA gene-targeted polymerase chain reaction -denaturing gradient gel electrophoresis (PCR-DGGE). The clone library was constructed after the liquid culturing of snow samples at 26°C. And microscopic method was employed to investigate the fungal diversity in the samples. In addition, outdoor air samples were also collected using mixed cellulose ester (MCE) filters and compared with snow samples with respect to described characteristics. The results revealed that snow samples had bacterial concentrations as much as 16000 CFU/ml for those cultured at 26°C, and the conductance levels ranged from 5.6×10(-6) to 2.4×10(-5) S. PCR-DGGE, sequencing and microscopic analysis revealed remarkable bacterial and fungal diversity differences between the snow samples and the outdoor air samples. In addition, DGGE banding profiles for the snow samples collected were also shown distinctly different from one another. Absent from the outdoor air, certain human, plant, and insect fungal pathogens were found in the snow samples. By calculation, culturable bacteria accounted for an average of 3.38% (±1.96%) of TOC for the snow samples, and 0.01% for that of outdoor air samples. The results here suggest that snow precipitations are important sources of fungal pathogens and ice nucleators, thus could affect local climate, human health and agriculture security.
Kuehl, Richard; Banderet, Florian; Egli, Adrian; Keller, Peter M; Frei, Reno; Döbele, Thomas; Eckstein, Friedrich; Widmer, Andreas F
2018-05-28
OBJECTIVEWorldwide, Mycobacterium chimaera infections have been linked to contaminated aerosols from heater-cooler units (HCUs) during open-heart surgery. These infections have mainly been associated with the 3T HCU (LivaNova, formerly Sorin). The reasons for this and the risk of transmission from other HCUs have not been systematically assessed.DESIGNProspective observational study.SETTINGUniversity Hospital Basel, Switzerland.METHODSContinuous microbiological surveillance of 3 types of HCUs in use (3T from LivaNova/Sorin and HCU30 and HCU40 from Maquet) was initiated in June 2014, coupled with an epidemiologic workup. Monthly water and air samples were taken. Construction design was analyzed, and exhausted airflow was measured.RESULTS Mycobacterium chimaera grew in 8 of 12 water samples (66%) and 22 of 24 air samples (91%) of initial 3T HCUs in use, and in 2 of 83 water samples (2%) and 0 of 41 (0%) air samples of new replacement 3T HCUs. Moreover, 7 of 12 water samples (58%) and 0 of 4 (0%) air samples from the HCU30 were positive, and 0 of 64 (0%) water samples and 0 of 50 (0%) air samples from the HCU40 were positive. We identified 4 relevant differences in HCU design compared to the 3T: air flow direction, location of cooling ventilators, continuous cooling of the water tank at 4°C, and an electronic alarm in the HCU40 reminding the user of the next disinfection cycle.CONCLUSIONSAll infected patients were associated with a 3T HCU. The individual HCU design may explain the different risk of disseminating M. chimaera into the air of the operating room. These observations can help the construction of improved devices to ensure patient safety during cardiac surgery.Infect Control Hosp Epidemiol 2018;1-7.
Genet, Chalachew; Kibru, Gebre; Tsegaye, Wondewosen
2011-03-01
Surgical site infection is the second most common health care associated infection. One of the risk factors for such infection is bacterial contamination of operating rooms' and surgical wards' indoor air. In view of that, the microbiological quality of air can be considered as a mirror of the hygienic condition of these rooms. Thus, the objective of this study was to determine the bacterial load and antibiotic susceptibility pattern of isolates in operating rooms' and surgical wards' indoor air of Jimma University Specialized Hospital. A cross sectional study was conducted to measure indoor air microbial quality of operating rooms and surgical wards from October to January 2009/2010 on 108 indoor air samples collected in twelve rounds using purposive sampling technique by Settle Plate Method (Passive Air Sampling following 1/1/1 Schedule). Sample processing and antimicrobial susceptibility testing were done following standard bacteriological techniques. The data was analyzed using SPSS version 16 and interpreted according to scientifically determined baseline values initially suggested by Fisher. The mean aerobic colony counts obtained in OR-1(46cfu/hr) and OR-2(28cfu/hr) was far beyond the set 5-8cfu/hr acceptable standards for passive room. Similarly the highest mean aerobic colony counts of 465cfu/hr and 461cfu/hr were observed in Female room-1 and room-2 respectively when compared to the acceptable range of 250-450cfu/hr. In this study only 3 isolates of S. pyogenes and 48 isolates of S. aureus were identified. Over 66% of S. aureus was identified in Critical Zone of Operating rooms. All isolates of S. aureus showed 100% and 82.8% resistance to methicillin and ampicillin respectively. Higher degree of aerobic bacterial load was measured from operating rooms' and surgical wards' indoor air. Reducing foot trafficking, improving the ventilation system and routine cleaning has to be made to maintain the aerobic bacteria load with in optimal level.
USDA-ARS?s Scientific Manuscript database
Whole air sampling using containers such as flexible bags or rigid canisters is commonly used to collect samples of volatile organic compounds (VOC) in air. The objective of this study was to compare the stability of polyester aluminum (PEA) and polyvinyl fluoride (PVF, brand name Tedlar®) bags for ...
High frequency resolution terahertz time-domain spectroscopy
NASA Astrophysics Data System (ADS)
Sangala, Bagvanth Reddy
2013-12-01
A new method for the high frequency resolution terahertz time-domain spectroscopy is developed based on the characteristic matrix method. This method is useful for studying planar samples or stack of planar samples. The terahertz radiation was generated by optical rectification in a ZnTe crystal and detected by another ZnTe crystal via electro-optic sampling method. In this new characteristic matrix based method, the spectra of the sample and reference waveforms will be modeled by using characteristic matrices. We applied this new method to measure the optical constants of air. The terahertz transmission through the layered systems air-Teflon-air-Quartz-air and Nitrogen gas-Teflon-Nitrogen gas-Quartz-Nitrogen gas was modeled by the characteristic matrix method. A transmission coefficient is derived from these models which was optimized to fit the experimental transmission coefficient to extract the optical constants of air. The optimization of an error function involving the experimental complex transmission coefficient and the theoretical transmission coefficient was performed using patternsearch algorithm of MATLAB. Since this method takes account of the echo waveforms due to reflections in the layered samples, this method allows analysis of longer time-domain waveforms giving rise to very high frequency resolution in the frequency-domain. We have presented the high frequency resolution terahertz time-domain spectroscopy of air and compared the results with the literature values. We have also fitted the complex susceptibility of air to the Lorentzian and Gaussian functions to extract the linewidths.
Carson, Christine F; Inglis, Timothy JJ
2018-01-01
This study investigated aerosolized viable bacteria in a university research laboratory during operation of an acoustic-assisted flow cytometer for antimicrobial susceptibility testing by sampling room air before, during and after flow cytometer use. The aim was to assess the risk associated with use of an acoustic-assisted flow cytometer analyzing unfixed bacterial suspensions. Air sampling in a nearby clinical laboratory was conducted during the same period to provide context for the existing background of microorganisms that would be detected in the air. The three species of bacteria undergoing analysis by flow cytometer in the research laboratory were Klebsiella pneumoniae, Burkholderia thailandensis and Streptococcus pneumoniae. None of these was detected from multiple 1000 L air samples acquired in the research laboratory environment. The main cultured bacteria in both locations were skin commensal and environmental bacteria, presumed to have been disturbed or dispersed in laboratory air by personnel movements during routine laboratory activities. The concentrations of bacteria detected in research laboratory air samples were reduced after interventional cleaning measures were introduced and were lower than those in the diagnostic clinical microbiology laboratory. We conclude that our flow cytometric analyses of unfixed suspensions of K. pneumoniae, B. thailandensis and S. pneumoniae do not pose a risk to cytometer operators or other personnel in the laboratory but caution against extrapolation of our results to other bacteria and/or different flow cytometric experimental procedures. PMID:29608197
Air bubbles and hemolysis of blood samples during transport by pneumatic tube systems.
Mullins, Garrett R; Bruns, David E
2017-10-01
Transport of blood samples through pneumatic tube systems (PTSs) generates air bubbles in transported blood samples and, with increasing duration of transport, the appearance of hemolysis. We investigated the role of air-bubble formation in PTS-induced hemolysis. Air was introduced into blood samples for 0, 1, 3 or 5min to form air bubbles. Hemolysis in the blood was assessed by (H)-index, lactate dehydrogenase (LD) and potassium in plasma. In an effort to prevent PTS-induced hemolysis, blood sample tubes were completely filled, to prevent air bubble formation, and compared with partially filled samples after PTS transport. We also compared hemolysis in anticoagulated vs clotted blood subjected to PTS transport. As with transport through PTSs, the duration of air bubble formation in blood by a gentle stream of air predicted the extent of hemolysis as measured by H-index (p<0.01), LD (p<0.01), and potassium (p<0.02) in plasma. Removing air space in a blood sample prevented bubble formation and fully protected the blood from PTS-induced hemolysis (p<0.02 vs conventionally filled collection tube). Clotted blood developed less foaming during PTS transport and was partially protected from hemolysis vs anticoagulated blood as indicated by lower LD (p<0.03) in serum than in plasma after PTS sample transport. Prevention of air bubble formation in blood samples during PTS transport protects samples from hemolysis. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Melymuk, Lisa; Bohlin-Nizzetto, Pernilla; Prokeš, Roman; Kukučka, Petr; Přibylová, Petra; Vojta, Šimon; Kohoutek, Jiří; Lammel, Gerhard; Klánová, Jana
2017-10-01
Degradation of semivolatile organic compounds (SVOCs) occurs naturally in ambient air due to reactions with reactive trace gases (e.g., ozone, NOx). During air sampling there is also the possibility for degradation of SVOCs within the air sampler, leading to underestimates of ambient air concentrations. We investigated the possibility of this sampling artifact in commonly used active and passive air samplers for seven classes of SVOCs, including persistent organic pollutants (POPs) typically covered by air monitoring programs, as well as SVOCs of emerging concern. Two active air samplers were used, one equipped with an ozone denuder and one without, to compare relative differences in mass of collected compounds. Two sets of passive samplers were also deployed to determine the influence of degradation during longer deployment times in passive sampling. In active air samplers, comparison of the two sampling configurations suggested degradation of particle-bound polycyclic aromatic hydrocarbons (PAHs), with concentrations up to 2× higher in the denuder-equipped sampler, while halogenated POPs did not have clear evidence of degradation. In contrast, more polar, reactive compounds (e.g., organophosphate esters and current use pesticides) had evidence of losses in the sampler with denuder. This may be caused by the denuder itself, suggesting sampling bias for these compounds can be created when typical air sampling apparatuses are adapted to limit degradation. Passive air samplers recorded up to 4× higher concentrations when deployed for shorter consecutive sampling periods, suggesting that within-sampler degradation may also be relevant in passive air monitoring programs.
Holton, Chase; Luo, Hong; Dahlen, Paul; Gorder, Kyle; Dettenmaier, Erik; Johnson, Paul C
2013-01-01
Current vapor intrusion (VI) pathway assessment heavily weights concentrations from infrequent (monthly-seasonal) 24 h indoor air samples. This study collected a long-term and high-frequency data set that can be used to assess indoor air sampling strategies for answering key pathway assessment questions like: "Is VI occurring?", and "Will VI impacts exceed thresholds of concern?". Indoor air sampling was conducted for 2.5 years at 2-4 h intervals in a house overlying a dilute chlorinated solvent plume (10-50 μg/L TCE). Indoor air concentrations varied by 3 orders of magnitude (<0.01-10 ppbv TCE) with two recurring behaviors. The VI-active behavior, which was prevalent in fall, winter, and spring involved time-varying impacts intermixed with sporadic periods of inactivity; the VI-dormant behavior, which was prevalent in the summer, involved long periods of inactivity with sporadic VI impacts. These data were used to study outcomes of three simple sparse data sampling plans; the probabilities of false-negative and false-positive decisions were dependent on the ratio of the (action level/true mean of the data), the number of exceedances needed, and the sampling strategy. The analysis also suggested a significant potential for poor characterization of long-term mean concentrations with sparse sampling plans. The results point to a need for additional dense data sets and further investigation into the robustness of possible VI assessment paradigms. As this is the first data set of its kind, it is unknown if the results are representative of other VI-sites.
Evaluation of air quality in a megacity using statistics tools
NASA Astrophysics Data System (ADS)
Ventura, Luciana Maria Baptista; de Oliveira Pinto, Fellipe; Soares, Laiza Molezon; Luna, Aderval Severino; Gioda, Adriana
2018-06-01
Local physical characteristics (e.g., meteorology and topography) associate to particle concentrations are important to evaluate air quality in a region. Meteorology and topography affect air pollutant dispersions. This study used statistics tools (PCA, HCA, Kruskal-Wallis, Mann-Whitney's test and others) to a better understanding of the relationship between fine particulate matter (PM2.5) levels and seasons, meteorological conditions and air basins. To our knowledge, it is one of the few studies performed in Latin America involving all parameters together. PM2.5 samples were collected in six sampling sites with different emission sources (industrial, vehicular, soil dust) in Rio de Janeiro, Brazil. The PM2.5 daily concentrations ranged from 1 to 61 µg m-3, with averages higher than the annual limit (15 µg m-3) for some of the sites. The results of the statistics evaluation showed that PM2.5 concentrations were not influenced by seasonality. Furthermore, air basins defined previously were not confirmed, because some sites presented similar emission sources. Therefore, new redefinitions of air basins need to be done, once they are important to air quality management.
Evaluation of air quality in a megacity using statistics tools
NASA Astrophysics Data System (ADS)
Ventura, Luciana Maria Baptista; de Oliveira Pinto, Fellipe; Soares, Laiza Molezon; Luna, Aderval Severino; Gioda, Adriana
2017-03-01
Local physical characteristics (e.g., meteorology and topography) associate to particle concentrations are important to evaluate air quality in a region. Meteorology and topography affect air pollutant dispersions. This study used statistics tools (PCA, HCA, Kruskal-Wallis, Mann-Whitney's test and others) to a better understanding of the relationship between fine particulate matter (PM2.5) levels and seasons, meteorological conditions and air basins. To our knowledge, it is one of the few studies performed in Latin America involving all parameters together. PM2.5 samples were collected in six sampling sites with different emission sources (industrial, vehicular, soil dust) in Rio de Janeiro, Brazil. The PM2.5 daily concentrations ranged from 1 to 61 µg m-3, with averages higher than the annual limit (15 µg m-3) for some of the sites. The results of the statistics evaluation showed that PM2.5 concentrations were not influenced by seasonality. Furthermore, air basins defined previously were not confirmed, because some sites presented similar emission sources. Therefore, new redefinitions of air basins need to be done, once they are important to air quality management.
Microbiological quality of air in free-range and box-stall stable horse keeping systems.
Wolny-Koładka, Katarzyna
2018-04-07
The aim of this study was to assess the microbiological quality of air in three horse riding centers differing in the horse keeping systems. The air samples were collected in one facility with free-range horse keeping system and two with box stalls of different sizes. The samples were collected over a period of 3 years (2015-2017), four times per year (spring, summer, autumn, winter) to assess the effect of seasonal changes. The prevalence of aerobic mesophilic bacteria, mold fungi, actinomycetes, Staphylococcus spp., and Escherichia coli was determined by the air collision method on Petri dishes with appropriate microbiological media. At the same time, air temperature, relative humidity, and particulate matter concentration (PM 10 , PM 2.5 ) were measured. It was found that the horse keeping system affects the occurrence of the examined airborne microorganisms. Over the 3-year period of study, higher temperature and humidity, as well as particulate matter concentration-which notoriously exceeded limit values-were observed in the facilities with the box-stall system. The air sampled from the largest horse riding center, with the largest number of horses and the box-stall system of horse keeping, was also characterized by the heaviest microbiological contamination. Among others, bacteria from the following genera: Staphylococcus spp., Streptococcus spp., Bacillus spp., and E. coli and fungi from the genera Aspergillus, Fusarium, Mucor, Rhizopus, Penicillium, Trichothecium, Cladosporium, and Alternaria were identified in the analyzed samples.
Wan, Gwo-Hwa; Huang, Chung-Guei; Chung, Fen-Fang; Lin, Tzou-Yien; Tsao, Kuo-Chien; Huang, Yhu-Chering
2016-04-01
Few studies have assessed viral contamination in the rooms of hospital wards. This cross-sectional study evaluated the air and objects in patient-occupied rooms in pediatric wards for the presence of common respiratory viruses and Mycoplasma pneumoniae.Air samplers were placed at a short (60-80 cm) and long (320 cm) distance from the head of the beds of 58 pediatric patients, who were subsequently confirmed to be infected with enterovirus (n = 17), respiratory syncytial virus (RSV) (n = 13), influenza A virus (n = 13), adenovirus (n = 9), or M pneumoniae (n = 6). Swab samples were collected from the surfaces of 5 different types of objects in the patients' rooms. All air and swab samples were analyzed via real-time quantitative polymerase chain reaction assay for the presence of the above pathogens.All pathogens except enterovirus were detected in the air, on the objects, or in both locations in the patients' rooms. The detection rates of influenza A virus, adenovirus, and M pneumoniae for the long distance air sampling were 15%, 67%, and 17%, respectively. Both adenovirus and M pneumoniae were detected at very high rates, with high concentrations, on all sampled objects.The respiratory pathogens RSV, influenza A virus, adenovirus, and M pneumoniae were detected in the air and/or on the objects in the pediatric ward rooms. Appropriate infection control measures should be strictly implemented when caring for such patients.
Biomass fuel use and the exposure of children to particulate air pollution in southern Nepal
Devakumar, D.; Semple, S.; Osrin, D.; Yadav, S.K.; Kurmi, O.P.; Saville, N.M.; Shrestha, B.; Manandhar, D.S.; Costello, A.; Ayres, J.G.
2014-01-01
The exposure of children to air pollution in low resource settings is believed to be high because of the common use of biomass fuels for cooking. We used microenvironment sampling to estimate the respirable fraction of air pollution (particles with median diameter less than 4 μm) to which 7–9 year old children in southern Nepal were exposed. Sampling was conducted for a total 2649 h in 55 households, 8 schools and 8 outdoor locations of rural Dhanusha. We conducted gravimetric and photometric sampling in a subsample of the children in our study in the locations in which they usually resided (bedroom/living room, kitchen, veranda, in school and outdoors), repeated three times over one year. Using time activity information, a 24-hour time weighted average was modeled for all the children in the study. Approximately two-thirds of homes used biomass fuels, with the remainder mostly using gas. The exposure of children to air pollution was very high. The 24-hour time weighted average over the whole year was 168 μg/m3. The non-kitchen related samples tended to show approximately double the concentration in winter than spring/autumn, and four times that of the monsoon season. There was no difference between the exposure of boys and girls. Air pollution in rural households was much higher than the World Health Organization and the National Ambient Air Quality Standards for Nepal recommendations for particulate exposure. PMID:24533994
Liu, Xiaojun; Wu, Yanyan; Hu, Yongxin; Liu, Denglai; Zhang, Jin; Chen, Cheng; Yuan, Zhaokang; Lu, Yuanan
2016-11-01
To improve the public's awareness of urban air pollution and promote establishment of more efficient policy toward urban air pollution, we investigated the government employees' perceptions of current urban air pollution and their willingness to pay (WTP) taxes for improved quality in Nanchang, China. Stratified cluster sampling strategy was used to distribute 629 questionnaires, and 608 were completed anonymously, yielding a 96.7 % response rate. Descriptive statistics frequencies and proportions were used to summarize the sample characteristics, and logistic regression models were performed to assess the associations of perception of urban air quality and WTP versus demographic variables. We found low awareness of urban air pollution (34.5 %) as well as low WTP (44.9 %), especially among the middle aged people (age 30-39 and age 40-49). Our study shows that female employees have better awareness of urban air pollution but much less willingness to pay for air quality improvement. Majority of the government employees showed their support to the government for more effective policies toward environmental protection, indicating more enhanced public education and environmental protection campaigns to improve the public's awareness of air pollution and work with every citizen to improve air quality. This study also obtained baseline information useful to the local regional and even national government in developing nations in their attempt to control urban air pollution in future.
Air Combat Training: Good Stick Index Validation. Final Report for Period 3 April 1978-1 April 1979.
ERIC Educational Resources Information Center
Moore, Samuel B.; And Others
A study was conducted to investigate and statistically validate a performance measuring system (the Good Stick Index) in the Tactical Air Command Combat Engagement Simulator I (TAC ACES I) Air Combat Maneuvering (ACM) training program. The study utilized a twelve-week sample of eighty-nine student pilots to statistically validate the Good Stick…
Air- and Dustborne Mycoflora in Houses Free of Water Damage and Fungal Growth
Horner, W. Elliott; Worthan, Anthony G.; Morey, Philip R.
2004-01-01
Typically, studies on indoor fungal growth in buildings focus on structures with known or suspected water damage, moisture, and/or indoor fungal growth problems. Reference information on types of culturable fungi and total fungal levels are generally not available for buildings without these problems. This study assessed 50 detached single-family homes in metropolitan Atlanta, Ga., to establish a baseline of “normal and typical” types and concentrations of airborne and dustborne fungi in urban homes which were predetermined not to have noteworthy moisture problems or indoor fungal growth. Each home was visually examined, and samples of indoor and outdoor air and of indoor settled dust were taken in winter and summer. The results showed that rankings by prevalence and abundance of the types of airborne and dustborne fungi did not differ from winter to summer, nor did these rankings differ when air samples taken indoors were compared with those taken outdoors. Water indicator fungi were essentially absent from both air and dust samples. The air and dust data sets were also examined specifically for the proportions of colonies from ecological groupings such as leaf surface fungi and soil fungi. In the analysis of dust for culturable fungal colonies, leaf surface fungi constituted a considerable portion (>20%) of the total colonies in at least 85% of the samples. Thus, replicate dust samples with less than 20% of colonies from leaf surface fungi are unlikely to be from buildings free of moisture or mold growth problems. PMID:15528497
Ambient air metallic pollutant study at HAF areas during 2013-2014
NASA Astrophysics Data System (ADS)
Fang, Guor-Cheng; Kuo, Yu-Chen; Zhuang, Yuan-Jie
2015-05-01
This study characterized diurnal variations of the total suspended particulate (TSP) concentrations, dry deposition flux and dry deposition velocity of metallic elements at Taichung Harbor (Harbor), Gong Ming Junior High School (Airport) and Sha lu Farmland (Farmland) sampling sites in central Taiwan between August, 2013 and July, 2014 in this study. The result indicated that: 1) the ambient air particulate concentrations, dry depositions were displayed as Harbor > Farmland > Airport during the day time sampling period. However, dry deposition velocities were shown as Airport > Harbor > Farmland for this study. 2) The ambient air particulate concentrations, dry depositions were displayed as Airport > Harbor > Farmland during the night time sampling period. However, dry deposition velocities were shown as Farmland > Harbor > Airport for this study. 3) The metallic element Zn has the average highest concentrations at Airport, Harbor and Farmland among all the metallic elements during the day time sampling period in this study. 4) There were significant differences for the metallic elements (Cr, Cu, Zn and Pb) in dry depositions at these three characteristic sampling sites (HAF) for the night time sampling period. The only exception is metallic element Cd. It displayed that there were no significant differences for the metallic element Cd at the Airport and Farmland sampling sites during the night time sampling period. 5) The average highest values for the metallic element Cu in TSP among the three characteristic sampling sites occurred during the fall and winter seasons for this study. As for the dry depositions, the average highest values in dry deposition among the three characteristic sampling sites occurred during the spring and summer seasons for this study. 6) The average highest values for the metallic element Cd in TSP among the three characteristic sampling sites occurred during the spring and summer seasons for this study. As for the dry depositions, the average highest values in dry deposition among the three characteristic sampling sites occurred during fall and winter for this study.
Pistonesi, Marcelo F; Di Nezio, María S; Centurión, María E; Lista, Adriana G; Fragoso, Wallace D; Pontes, Márcio J C; Araújo, Mário C U; Band, Beatriz S Fernández
2010-12-15
In this study, a novel, simple, and efficient spectrofluorimetric method to determine directly and simultaneously five phenolic compounds (hydroquinone, resorcinol, phenol, m-cresol and p-cresol) in air samples is presented. For this purpose, variable selection by the successive projections algorithm (SPA) is used in order to obtain simple multiple linear regression (MLR) models based on a small subset of wavelengths. For comparison, partial least square (PLS) regression is also employed in full-spectrum. The concentrations of the calibration matrix ranged from 0.02 to 0.2 mg L(-1) for hydroquinone, from 0.05 to 0.6 mg L(-1) for resorcinol, and from 0.05 to 0.4 mg L(-1) for phenol, m-cresol and p-cresol; incidentally, such ranges are in accordance with the Argentinean environmental legislation. To verify the accuracy of the proposed method a recovery study on real air samples of smoking environment was carried out with satisfactory results (94-104%). The advantage of the proposed method is that it requires only spectrofluorimetric measurements of samples and chemometric modeling for simultaneous determination of five phenols. With it, air is simply sampled and no pre-treatment sample is needed (i.e., separation steps and derivatization reagents are avoided) that means a great saving of time. Copyright © 2010 Elsevier B.V. All rights reserved.
Kamal, Ali; Burke, Janet; Vesper, Stephen; Batterman, Stuart; Vette, Alan; Godwin, Christopher; Chavez-Camarena, Marina; Norris, Gary
2014-01-01
The Near-Road Exposures and Effects of Urban Air Pollutants Study (NEXUS) investigated the impact of exposure to traffic-related air pollution on the respiratory health of asthmatic children in Detroit, Michigan. Since indoor mold exposure may also contribute to asthma, floor dust samples were collected in participants homes (n = 112) to assess mold contamination using the Environmental Relative Moldiness Index (ERMI). The repeatability of the ERMI over time, as well as ERMI differences between rooms and dust collection methods, was evaluated for insights into the application of the ERMI metric. ERMI values for the standard settled floor dust samples had a mean ± standard deviation of 14.5 ± 7.9, indicating high levels of mold contamination. ERMI values for samples collected from the same home 1 to 7 months apart (n = 52) were consistent and without systematic bias. ERMI values for separate bedroom and living room samples were highly correlated (r = 0.69, n = 66). Vacuum bag dust ERMI values were lower than for floor dust but correlated (r = 0.58, n = 28). These results support the use of the ERMI to evaluate residential mold exposure as a confounder in air pollution health effects studies.
2014-01-01
Background Naphthalene exposures for most non-occupationally exposed individuals occur primarily indoors at home. Residential indoor sources include pest control products (specifically moth balls), incomplete combustion such as cigarette smoke, woodstoves and cooking, some consumer and building products, and emissions from gasoline sources found in attached garages. The study aim was to assess naphthalene exposure in pregnant women from Canada, using air measurements and biomarkers of exposure. Methods Pregnant women residing in Ottawa, Ontario completed personal and indoor air sampling, and questionnaires. During pregnancy, pooled urine voids were collected over two 24-hour periods on a weekday and a weekend day. At 2–3 months post-birth, they provided a spot urine sample and a breast milk sample following the 24-hour air monitoring. Urines were analyzed for 1-naphthol and 2-naphthol and breast milk for naphthalene. Simple linear regression models examined associations between known naphthalene sources, air and biomarker samples. Results Study recruitment rate was 11.2% resulting in 80 eligible women being included. Weekday and weekend samples were highly correlated for both personal (r = 0.83, p < 0.0001) and indoor air naphthalene (r = 0.91, p < 0.0001). Urine specific gravity (SG)-adjusted 2-naphthol concentrations collected on weekdays and weekends (r = 0.78, p < 0.001), and between pregnancy and postpartum samples (r = 0.54, p < 0.001) were correlated. Indoor and personal air naphthalene concentrations were significantly higher post-birth than during pregnancy (p < 0.0001 for signed rank tests); concurrent urine samples were not significantly different. Naphthalene in breast milk was associated with urinary 1-naphthol: a 10% increase in 1-naphthol was associated with a 1.6% increase in breast milk naphthalene (95% CI: 0.2%-3.1%). No significant associations were observed between naphthalene sources reported in self-administered questionnaires and the air or biomarker concentrations. Conclusions Median urinary concentrations of naphthalene metabolites tended to be similar to (1-naphthol) or lower (2-naphthol) than those reported in a Canadian survey of women of reproductive age. Only urinary 1-naphthol and naphthalene in breast milk were associated. Potential reasons for the lack of other associations include a lack of sources, varying biotransformation rates and behavioural differences over time. PMID:24767676
NASA Astrophysics Data System (ADS)
Handa, D.; Nakajima, H.; Nakaema, F.; Arakaki, T.; Tanahara, A.
2008-12-01
The economic development and population growth in recent Asia spread air pollution. Emission rate of air pollutants from Asia, in particular oxides of nitrogen, surpassed those from North America and Europe and should continue to exceed them for decades. The study of the air pollution transported from Asian continent has gained a special attention in Japan. Okinawa Island is situated approximately 1500 km south of Tokyo, Japan, 2000 km southeast of Beijing, China, and 1000 km south of South Korea. Its location is ideal in observing East Asian atmospheric aerosols because maritime air mass prevails during summer, while continental air mass dominates during fall, winter, and spring. The maritime air mass data can be seen as background and can be compared with continental air masses which have been affected by anthropogenic activities. In 2005, Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS) was established by the National Institute for Environmental Studies (NIES) at the northern tip of Okinawa Island, Japan to monitor the air quality of Asia. Bulk aerosol samples were collected on quartz filters by using a high volume air sampler. Sampling duration was one week for each sample. We determined the concentrations of water-soluble anions, cations and dissolved organic carbon in the bulk aerosols collected at the CHAAMS, using ion chromatography, atomic absorption spectrometry, and total organic carbon analyzer, respectively. Seasonal variation of water-soluble chemical components showed that the concentrations were relatively low in summer, higher in fall and winter, and the highest in spring. When air mass came from Asian Continent, the concentrations of water-soluble chemical components were much higher compared to the other directions.
Bacterial Community in Water and Air of Two Sub-Alpine Lakes in Taiwan.
Tandon, Kshitij; Yang, Shan-Hua; Wan, Min-Tao; Yang, Chia-Chin; Baatar, Bayanmunkh; Chiu, Chih-Yu; Tsai, Jeng-Wei; Liu, Wen-Cheng; Tang, Sen-Lin
2018-04-21
Very few studies have attempted to profile the microbial communities in the air above freshwater bodies, such as lakes, even though freshwater sources are an important part of aquatic ecosystems and airborne bacteria are the most dispersible microorganisms on earth. In the present study, we investigated microbial communities in the waters of two high mountain sub-alpine montane lakes-located 21 km apart and with disparate trophic characteristics-and the air above them. Although bacteria in the lakes had locational differences, their community compositions remained constant over time. However, airborne bacterial communities were diverse and displayed spatial and temporal variance. Proteobacteria, Actinobacteria, Bacteroidetes, and Cyanobacteria were dominant in both lakes, with different relative abundances between lakes, and Parcubacteria (OD1) was dominant in air samples for all sampling times, except two. We also identified certain shared taxa between lake water and the air above it. The results obtained on these communities in the present study provide putative candidates to study how airborne communities shape lake water bacterial compositions and vice versa.
Stability of athlete blood passport parameters during air freight.
Ashenden, M; Sharpe, K; Plowman, J; Allbon, G; Lobigs, L; Baron, A; Gore, C J
2014-10-01
Fluctuations in ambient temperature and pressure, as well as physical jostling, may affect the stability of whole blood samples transported by air freight. The aim of this study was to characterize the stability of key blood variables during air freight and to investigate whether vibration or reduced pressure alone affected results. Over a 72-h interval, we evaluated the stability of full blood count indices (plus reticulocytes) in tubes that were air-freighted a total of 2, 10 and 28 h. We also examined the impact of 24 h of reduced atmospheric pressure (750 hpa or approximately 2500 m.a.s.l) and vibration (5 Hz). Samples were measured on a Sysmex XT-2000i instrument. The two key variables in the context of antidoping (haemoglobin concentration, reticulocytes) remained stable over a 72-h period regardless of the duration of air freight. Atmospheric pressure and vibration had no discernible effect. Whole blood samples stored in NanoCool devices can be relied upon to remain stable for at least 72 h despite interim air freight. © 2013 John Wiley & Sons Ltd.
Abdollahi, Atousa; Eng, Anita; Jantunen, Liisa M; Ahrens, Lutz; Shoeib, Mahiba; Parnis, J Mark; Harner, Tom
2017-01-01
This study aimed to characterize the uptake of organophosphate esters (OPEs) by polyurethane foam (PUF) and sorbent-impregnated polyurethane foam (SIP) disk passive air samplers (PAS). Atmospheric OPE concentrations were monitored with high-volume active air samplers (HV-AAS) that were co-deployed with passive air samplers. Samples were analyzed for tris(2-chloroisopropyl) phosphate (TCIPP), tri(phenyl) phosphate (TPhP), tris(2-chloroethyl) phosphate (TCEP), and tris(2,3-dichloropropyl) phosphate (TDCIPP). The mean concentration of ∑OPEs in air was 2650 pg/m 3 for the HV-AAS. Sampling rates and the passive sampler medium (PSM)-air partition coefficient (K PSM-Air ) were calculated for individual OPEs. The average calculated sampling rates (R) for the four OPEs were 3.6 ± 1.2 and 4.2 ± 2.0 m 3 /day for the PUF and SIP disks, respectively, and within the range of the recommended default value of 4 ± 2 m 3 /day. Since most of the OPEs remained in the linear uptake phase during the study, COSMO-RS solvation theory and an oligomer-based model were used to estimate K PUF-Air for the OPEs. The estimated values of log K PUF-Air were 7.45 (TCIPP), 9.35 (TPhP), 8.44 (TCEP), and 9.67 (TDCIPP). Finally, four configurations of the PUF and SIP disks were tested by adjusting the distance of the gap opening between the upper and lower domes of the sampler housing: i.e. 2 cm, 1 cm, no gap and 1 cm overlap. The sampling rate did not differ significantly between these four configurations (p < 0.05). Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.
METHODOLOGY OF AMBIENT AIR MONITORING FOR POLYCYCLIC AROMATIC HYDROCARBONS
In the last decade, several studies of polycyclic aromatic hydrocarbons (PAH) in ambient air in the U.S. specifically investigated (1) the sampling efficiency of two sorbents for PAH in air: XAD-2 and polyurethane foam (PUP); (2) the storage stability of PAH on quartz fiber fil...
Choukri, Firas; Menotti, Jean; Sarfati, Claudine; Lucet, Jean-Christophe; Nevez, Gilles; Garin, Yves J F; Derouin, Francis; Totet, Anne
2010-08-01
Airborne transmission of Pneumocystis has been demonstrated in animal models and is highly probable in humans. However, information concerning burdens of Pneumocystis jirovecii (human-derived Pneumocystis) in exhaled air from infected patients is lacking. Our objective is to evaluate P. jirovecii air diffusion in patients with Pneumocystis pneumonia. Patients admitted with Pneumocystis pneumonia were prospectively enrolled from 9 January 2008 to 21 July 2009. Air samples (1.5 m(3)) were collected on liquid medium with a commercial sampler at 1-, 3-, 5-, and 8-m distances from patients' heads. Air control samples were collected away from Pneumocystis pneumonia patient wards and outdoors. Samples were examined for P. jirovecii detection and quantification using a real-time polymerase chain reaction assay targeting the mitochondrial large subunit ribosomal RNA gene. Forty patients were diagnosed as having Pneumocystis pneumonia. Air sampling was performed in the environment for 19 of them. At a 1-m distance from patients' heads, P. jirovecii DNA was detected in 15 (79.8%) of 19 patients, with fungal burdens ranging from 7.5 X 10³ to 4.5 X 10⁶ gene copies/m(3). These levels decreased with distance from the patients (P < .002). Nevertheless, 4 (33.3%) of the 12 samples taken at 8 m, in the corridor adjacent to their room, were still positive. Forty control samples were collected and remained negative. This study provides the first quantitative data on the spread of P. jirovecii in exhaled air from infected patients. It sustains the risk of P. jirovecii direct transmission in close contact with patients with Pneumocystis pneumonia and leads the way for initiating a quantitative risk assessment for airborne transmission of P. jirovecii.
NASA Astrophysics Data System (ADS)
Roubinet, Claire; Moreira, Manuel A.
2018-02-01
Noble gases in oceanic basalts always show the presence in variable proportions of a component having elemental and isotopic compositions that are similar to those of the atmosphere and distinct from the mantle composition. Although this component could be mantle-derived (e.g. subduction of air or seawater-derived noble gases trapped in altered oceanic crust and sediments), it is most often suggested that this air component is added after sample collection and probably during storage at ambient air, although the mechanism remains unknown. In an attempt to reduce this atmospheric component observed in MORBs, four experimental protocols have been followed in this study. These protocols are based on the hypothesis that air can be removed from the samples, as it appears to be sheltered in distinct vesicles compared to those filled with mantle gases. All of the protocols involve a glove box filled with nitrogen, and in certain cases, the samples are stored under primary vacuum (lower than 10-2 mbar) to pump air out or, alternatively, under high pressure of N2 to expel atmospheric noble gases. In all protocols, three components are observed: atmospheric, fractionated atmospheric and magmatic. The fractionated air component seems to be derived from the non-vitreous part of the pillow-lava, which has cooled more slowly. This component is enriched in Ne relative to Ar, reflecting a diffusive process. This contaminant has already been observed in other studies and thus seems to be relatively common. Although it is less visible, unfractionated air has also been detected in some crushing steps, which tends to indicate that despite the experiments, air is still present in the vesicles. This result is surprising, since studies have demonstrated that atmospheric contamination could be limited if samples were stored under nitrogen quickly after their recovery from the seafloor. Thus, the failure of the protocols could be explained by the insufficient duration of these protocols or by the inaccessibility of vesicles filled with air as assessed by (Ballentine and Barfod, 2000).
Assessment of depleted uranium in South-Western Iran.
Yousefi, Hossein; Najafi, Abdullah
2013-10-01
Depleted uranium (DU) has been used in a number of conflicts most notably during the Gulf War in Iraq and existence of it has been reported in Kuwait by IAEA experts. Due to heavy sand storms prevailing into the direction to South West of Iran transporting sand originating from Iraq, the probability that DU could be moved is considered high. Therefore it was decided to take some air and soil samples near border line and some nearest cities. The study was focused on finding DU in air and soil of these south-west provinces. 22 air samples and 20 soil samples were collected and analyzed on their contents of uranium isotopes by alpha, beta and gamma spectrometry. The air and soil samples have been measured by use of an alpha-beta counter and by a gamma spectrometer, respectively. Results showed that there is no radiation impact from DU and so no DU has been transported via sand storms since all results were obtained below the detection limit. Copyright © 2013 Elsevier Ltd. All rights reserved.
Chaemfa, Chakra; Wild, Edward; Davison, Brian; Barber, Jonathan L; Jones, Kevin C
2009-06-01
Polyurethane foam disks are a cheap and versatile tool for sampling persistent organic pollutants (POPs) from the air in ambient, occupational and indoor settings. This study provides important background information on the ways in which the performance of these commonly used passive air samplers may be influenced by the key environmental variables of wind speed and aerosol entrapment. Studies were performed in the field, a wind tunnel and with microscopy techniques, to investigate deployment conditions and foam density influence on gas phase sampling rates (not obtained in this study) and aerosol trapping. The study showed: wind speed inside the sampler is greater on the upper side of the sampling disk than the lower side and tethered samplers have higher wind speeds across the upper and lower surfaces of the foam disk at a wind speed > or = 4 m/s; particles are trapped on the foam surface and within the body of the foam disk; fine (<1 um) particles can form clusters of larger size inside the foam matrix. Whilst primarily designed to sample gas phase POPs, entrapment of particles ensures some 'sampling' of particle bound POPs species, such as higher molecular weight PAHs and PCDD/Fs. Further work is required to investigate how quantitative such entrapment or 'sampling' is under different ambient conditions, and with different aerosol sizes and types.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 8 2011-07-01 2011-07-01 false Air sampling. 61.34 Section 61.34... sampling. (a) Stationary sources subject to § 61.32(b) shall locate air sampling sites in accordance with a... concentrations calculated within 30 days after filters are collected. Records of concentrations at all sampling...
2014-01-01
Residential exposure can dominate total exposure for commercial chemicals of health concern; however, despite the importance of consumer exposures, methods for estimating household exposures remain limited. We collected house dust and indoor air samples in 49 California homes and analyzed for 76 semivolatile organic compounds (SVOCs)—phthalates, polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and pesticides. Sixty chemicals were detected in either dust or air and here we report 58 SVOCs detected in dust for the first time. In dust, phthalates (bis(2-ethylhexyl) phthalate, benzyl butyl phthalate, di-n-butyl phthalate) and flame retardants (PBDE 99, PBDE 47) were detected at the highest concentrations relative to other chemicals at the 95th percentile, while phthalates were highest at the median. Because SVOCs are found in both gas and condensed phases and redistribute from their original source over time, partitioning models can clarify their fate indoors. We use empirical data to validate air-dust partitioning models and use these results, combined with experience in SVOC exposure assessment, to recommend residential exposure measurement strategies. We can predict dust concentrations reasonably well from measured air concentrations (R2 = 0.80). Partitioning models and knowledge of chemical Koa elucidate exposure pathways and suggest priorities for chemical regulation. These findings also inform study design by allowing researchers to select sampling approaches optimized for their chemicals of interest and study goals. While surface wipes are commonly used in epidemiology studies because of ease of implementation, passive air sampling may be more standardized between homes and also relatively simple to deploy. Validation of passive air sampling methods for SVOCs is a priority. PMID:25488487
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mumford, J.L.; Lewtas, J.; Burton, R.M.
1990-01-01
The study was conducted to assess human exposure to air pollutants resulting from the use of kerosene heaters in mobile homes. It has been estimated that 15-17 million unvented kerosene heaters have been sold in the United States, and 33% of these heaters have been sold to mobile home residents. The emissions from kerosene heaters can result in high pollutants levels in mobile homes that have a small air volume and low ventilation rate. Indoor air exchange rate, temperature, and humidity were measured. Chemical analyses, including polycyclic aromatic hydrocarbon (PAH) and nitro PAH, also were performed on the indoor airmore » samples from a selected home with the kerosene heater on and off. Increases in CO and organic concentrations resulting from the use of kerosene heaters were found in most homes monitored. Chemical analysis data also suggested the presence of evaporated, unburned kerosene fuel present in semivolatile organics collected in the XAD samples. When kerosene heaters were on, 56% of the sampling days (in all homes) showed dose-response mutagenic activity and 19% showed mutagenic activity on the heater-off days. In comparison with the U.S. national ambient air standards, four out of the eight heaters investigated in this study emitted pollutants that exceeded the ambient air standards some days. These data suggested that emissions from unvented kerosene heaters can significantly impact indoor air quality in mobile homes and that these emissions contain carcinogenic compounds and can be potentially carcinogenic in humans.« less
Air contamination for predicting wound contamination in clean surgery: A large multicenter study.
Birgand, Gabriel; Toupet, Gaëlle; Rukly, Stephane; Antoniotti, Gilles; Deschamps, Marie-Noelle; Lepelletier, Didier; Pornet, Carole; Stern, Jean Baptiste; Vandamme, Yves-Marie; van der Mee-Marquet, Nathalie; Timsit, Jean-François; Lucet, Jean-Christophe
2015-05-01
The best method to quantify air contamination in the operating room (OR) is debated, and studies in the field are controversial. We assessed the correlation between 2 types of air sampling and wound contaminations before closing and the factors affecting air contamination. This multicenter observational study included 13 ORs of cardiac and orthopedic surgery in 10 health care facilities. For each surgical procedure, 3 microbiologic air counts, 3 particles counts of 0.3, 0.5, and 5 μm particles, and 1 bacteriologic sample of the wound before skin closure were performed. We collected data on surgical procedures and environmental characteristics. Of 180 particle counts during 60 procedures, the median log10 of 0.3, 0.5, and 5 μm particles was 7 (interquartile range [IQR], 6.2-7.9), 6.1 (IQR, 5.4-7), and 4.6 (IQR, 0-5.2), respectively. Of 180 air samples, 50 (28%) were sterile, 90 (50%) had 1-10 colony forming units (CFU)/m(3) and 40 (22%) >10 CFU/m(3). In orthopedic and cardiac surgery, wound cultures at closure were sterile for 24 and 9 patients, 10 and 11 had 1-10 CFU/100 cm(2), and 0 and 6 had >10 CFU/100 cm(2), respectively (P < .01). Particle sizes and a turbulent ventilation system were associated with an increased number of air microbial counts (P < .001), but they were not associated with wound contamination (P = .22). This study suggests that particle counting is a good surrogate of airborne microbiologic contamination in the OR. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Air pollution, inflammation and preterm birth in Mexico City: study design and methods.
O'Neill, Marie S; Osornio-Vargas, Alvaro; Buxton, Miatta A; Sánchez, Brisa N; Rojas-Bracho, Leonora; Castillo-Castrejon, Marisol; Mordhukovich, Irina B; Brown, Daniel G; Vadillo-Ortega, Felipe
2013-03-15
Preterm birth is one of the leading causes of perinatal mortality and is associated with long-term adverse health consequences for surviving infants. Preterm birth rates are rising worldwide, and no effective means for prevention currently exists. Air pollution exposure may be a significant cause of prematurity, but many published studies lack the individual, clinical data needed to elucidate possible biological mechanisms mediating these epidemiological associations. This paper presents the design of a prospective study now underway to evaluate those mechanisms in a cohort of pregnant women residing in Mexico City. We address how air quality may act together with other factors to induce systemic inflammation and influence the duration of pregnancy. Data collection includes: biomarkers relevant to inflammation in cervico-vaginal exudate and peripheral blood, along with full clinical information, pro-inflammatory cytokine gene polymorphisms and air pollution data to evaluate spatial and temporal variability in air pollution exposure. Samples are collected on a monthly basis and participants are followed for the duration of pregnancy. The data will be used to evaluate whether ambient air pollution is associated with preterm birth, controlling for other risk factors. We will evaluate which time windows during pregnancy are most influential in the air pollution and preterm birth association. In addition, the epidemiological study will be complemented with a parallel toxicology invitro study, in which monocytic cells will be exposed to air particle samples to evaluate the expression of biomarkers of inflammation. Copyright © 2012 Elsevier B.V. All rights reserved.
Air pollution, inflammation and preterm birth in Mexico City: Study design and methods
O’Neill, Marie S.; Osornio-Vargas, Alvaro; Buxton, Miatta A.; Sanchez, Brisa N.; Rojas-Bracho, Leonora; Castillo-Castrejon, Marisol; Mordhukovich, Irina B.; Brown, Daniel G.; Vadillo-Ortega, Felipe
2012-01-01
Preterm birth is one of the leading causes of perinatal mortality and is associated with long-term adverse health consequences for surviving infants. Preterm birth rates are rising worldwide, and no effective means for prevention currently exists. Air pollution exposure may be a significant cause of prematurity, but many published studies lack the individual, clinical data needed to elucidate possible biological mechanisms mediating these epidemiological associations. This paper presents the design of a prospective study now underway to evaluate those mechanisms in a cohort of pregnant women residing in Mexico City. We address how air quality may act together with other factors to induce systemic inflammation and influence the duration of pregnancy. Data collection includes: biomarkers relevant to inflammation in cervico-vaginal exudate and peripheral blood, along with full clinical information, pro-inflammatory cytokine gene polymorphisms and air pollution data to evaluate spatial and temporal variability in air pollution exposure. Samples are collected on a monthly basis and participants are followed for the duration of pregnancy. The data will be used to evaluate whether ambient air pollution is associated with preterm birth, controlling for other risk factors. We will evaluate which time windows during pregnancy are most influential in the air pollution and preterm birth association. In addition, the epidemiological study will be complemented with a parallel toxicology invitro study, in which monocytic cells will be exposed to air particle samples to evaluate the expression of biomarkers of inflammation. PMID:23177781
Padilla-Sánchez, Juan A; Papadopoulou, Eleni; Poothong, Somrutai; Haug, Line S
2017-11-07
Per- and polyfluoroalkyl substances (PFASs), including fluorotelomer alcohols (FTOHs), perfluoroalkyl sulfonamidoethanols (FOSEs), and perfluoroalkyl sulfonamides (FOSAs), were assessed in 61 residential indoor air and 15 personal air samples collected in Oslo area, Norway. FTOHs were detected in all samples, and the median concentrations in residential indoor air were 2970, 10400, and 3120 pg m -3 for 6:2, 8:2, and 10:2 FTOH, respectively. This is similar to or higher than previously reported in studies from the same geographical area and worldwide. FOSEs and FOSAs were detected in 49-70% and 7-13% of the residential indoor air samples, respectively. The median FTOH concentrations observed in personal air were 1970, 7170, and 1590 pg m -3 for 6:2, 8:2, and 10:2 FTOH, respectively, which is 30 to 50% lower than the median concentrations in residential indoor air. No FOSEs or FOSAs were detected above the method detection limit (MDL) in the personal air samples. Intakes of perfluorohexanoate (PFHxA), perfluoroheptanoate (PFHpA), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUnDA), and perfluorooctyl sulfonate (PFOS) through inhalation and biotransformation of PFAS precursors in air were estimated. Median intakes of 1.7, 0.17, 5.7, 0.57, 1.8, 0.18, and 2.3 pg kg bw -1 day -1 were obtained in residential indoor air, while 1.0, 0.10, 3.3, 0.33, 0.88, and 0.09 pg kg bw -1 day -1 were found in personal air for PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnDA, and PFOS, respectively. The median PFOA intakes from residential indoor air (5.7 pg kg bw -1 day -1 ) and personal air (3.3 pg kg bw -1 day -1 ) were both around 5 orders of magnitude lower than the tolerable daily intake (TDI) reported by the European Food Safety Authority (EFSA).
Śmiełowska, M; Zabiegała, B
2018-06-19
This study presents the results of studies aimed at the development of an analytical procedure for separation, identification, and determination of PBDEs compounds in dust samples collected from automotive cabin air filters and samples collected from filters installed as part of the air purification system in academic facilities. Ultrasound-assisted dispersive solid phase extraction (UA-dSPE) was found to perform better in terms of extract purification than the conventional SPE technique. GC-EIMS was used for final determination of analytes. The concentrations of PBDEs in car filters ranged from < LOD to 688 ng/g while from < LOD to 247 ng/g in dust from air conditioning filters. BDE-47 and BDE-100 were reported the dominating congeners. The estimated exposure to PBDEs via ingestion of dust from car filters varied from 0.00022 to 0.012 ng/day in toddlers and from 0.000036 to 0.0029 ng/day in adults; dust from air conditioning filters: from 0.017 to 0.25 ng/day in toddlers and from 0.0029 to 0.042 ng/day. In addition, an attempt was made at extracting PBDEs from a dust samples using the matrix solid-phase dispersion (MSPD) technique as a promising alternative to conventional SPE separations. Copyright © 2018 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Vuppala, P.; S. S, A.; Mareddy, A.
2004-12-01
Around the world cities in developing countries are rapidly growing as more and more people become urban dwellers resulting in increased level of air pollution caused by changes in transportation, energy production and industrial activities. Air quality is an issue of critical importance in view of the accumulating evidence showing the adverse effects of pollution on human health, agricultural crops, manmade environments and ecosystems. An integrated study for identification of appropriate sites for representative evaluation of air pollution, novel means of monitoring air quality, identifying the predominant sources of pollution, effective assessment of air quality and evaluation of different management strategies essential for the development of a healthy and livable region is carried out for Hyderabad metropolis in India using Remote sensing and Geographical Information System (GIS) based assessment tools. Correlation studies between the concentration level of pollutants in urban air and urban land use are also dealt with. Municipal Corporation of Hyderabad (MCH) is divided into eleven planning zones out of which the present study area i.e. Zone I & IIA comprises of industrial, highly commercial and densely populated areas, apart from medium and sparse residential areas making it environmentally sensitive. Sampling locations were identified based on the land use/ land cover of the region and air samples were collected from areas having varying land use patterns using a high volume air sampler. The samples were then analyzed for the presence of Sulphur oxides(SO--x), Oxides of Nitrogen(NO--x), Total Suspended Particulate Matter(TSPM) and Respirable Suspended Particulate Matter(RSPM) using standard protocols and maps showing spatial distribution of SOx, NO--x, TSPM & RSPM were prepared using curve fitting technique of Arc/Info & ArcView GIS software. Air Quality Index (AQI), indicating the overall quality of air and extent of pollution is also calculated, based on which the entire study area is classified into severely, highly, moderately and lightly polluted areas. Concentration of SOx and NOx were observed to be within limits, while particulate pollutants exceeded the standards prescribed by Central Pollution Control Board (CPCB). The major cause of pollution in the study area is attributed to the increasing vehicular movements and presence of commercial and public related activities such as shopping malls. It is observed for the category of severe air pollution that 42% of pollution is from dense residential areas, 19% from medium residential and 1% load of pollution from other public related activities. Based on the results obtained suitable remedial measures to combat the increasing urban air pollution are suggested in the study area. Key words: Air pollution, Remote sensing, Geographical Information System, Spatial distribution, Air quality index.
Seasonal variations of PCDD/Fs congeners in air, soil and eggs from a Polish small-scale farm.
Węgiel, Malgorzata; Chrząszcz, Ryszard; Maślanka, Anna; Grochowalski, Adam
2018-05-01
The transfer of dioxin from the environment to the food is a problem in a consumers' health protection. The study aimed to determine the concentration of dioxins in free-range chicken eggs, air and soil samples, collected during 12 months on an individual small farm, located in Małopolska region, Poland. In the majority of analyzed eggs, the concentrations of dioxin exceeded several times the legal limit of 2.5 pg WHO-TEQ g-1fat. Seasonal changes in the PCDD/Fs congeners in egg, air and soil samples were studied. During the winter season, when the combustion processes of the solid fuel in domestic furnaces are intensive, the PM10 concentration in the Małopolska region exceeds the legal limit (50μg/m3) even eight times. In this period, eggs, air and soil samples showed a higher share of PCDFs with a specific contribution of 2,3,7,8-TCDF. During the summer months, in the egg, air and soil samples, the share of PCDDs is higher with dominant OCDD and 1,2,3,4,6,7,8-HpCDDs, showing the effect of other combustion processes such as grass utilization or burning plastic wastes in controlled fires. In August, the month of the highest average air temperature and lowest rainfall amount, the highest toxicity of PCDD/Fs in eggs (9.52pgWHO-TEQ g-1fat) was found. Due to the similarity of the shares of PCDD/Fs congeners in total WHO-TEQ value we can take into account the influence of toxicity of PCDD/Fs in the air and soil on the toxicity in the eggs. Copyright © 2018. Published by Elsevier Ltd.
Filter for on-line air monitor unaffected by radon progeny and method of using same
Phillips, Terrance D.; Edwards, Howard D.
1999-01-01
An apparatus for testing air having contaminants and radon progeny therein. The apparatus includes a sampling box having an inlet for receiving the air and an outlet for discharging the air. The sampling box includes a filter made of a plate of sintered stainless steel. The filter traps the contaminants, yet allows at least a portion of the radon progeny to pass therethrough. A method of testing air having contaminants and radon progeny therein. The method includes providing a testing apparatus that has a sampling box with an inlet for receiving the air and an outlet for discharging the air, and has a sintered stainless steel filter disposed within said sampling box; drawing air from a source into the sampling box using a vacuum pump; passing the air through the filter; monitoring the contaminants trapped by the filter; and providing an alarm when a selected level of contaminants is reached. The filter traps the contaminants, yet allows at least a portion of the radon progeny to pass therethrough.
Brand, Willi A; Rothe, Michael; Sperlich, Peter; Strube, Martin; Wendeberg, Magnus
2016-07-15
The isotopic composition of greenhouse gases helps to constrain global budgets and to study sink and source processes. We present a new system for high-precision stable isotope measurements of carbon, hydrogen and oxygen in atmospheric methane and carbon dioxide. The design is intended for analyzing flask air samples from existing sampling programs without the need for extra sample air for methane analysis. CO2 and CH4 isotopes are measured simultaneously using two isotope ratio mass spectrometers, one for the analysis of δ(13) C and δ(18) O values and the second one for δ(2) H values. The inlet carousel delivers air from 16 sample positions (glass flasks 1-5 L and high-pressure cylinders). Three 10-port valves take aliquots from the sample stream. CH4 from 100-mL air aliquots is preconcentrated in 0.8-mL sample loops using a new cryo-trap system. A precisely calibrated working reference air is used in parallel with the sample according to the Principle of Identical Treatment. It takes about 36 hours for a fully calibrated analysis of a complete carousel including extractions of four working reference and one quality control reference air. Long-term precision values, as obtained from the quality control reference gas since 2012, account for 0.04 ‰ (δ(13) C values of CO2 ), 0.07 ‰ (δ(18) O values of CO2 ), 0.11 ‰ (δ(13) C values of CH4 ) and 1.0 ‰ (δ(2) H values of CH4 ). Within a single day, the system exhibits a typical methane δ(13) C standard deviation (1σ) of 0.06 ‰ for 10 repeated measurements. The system has been in routine operation at the MPI-BGC since 2012. Consistency of the data and compatibility with results from other laboratories at a high precision level are of utmost importance. A high sample throughput and reliability of operation are important achievements of the presented system to cope with the large number of air samples to be analyzed. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Insights from two industrial hygiene pilot e-cigarette passive vaping studies.
Maloney, John C; Thompson, Michael K; Oldham, Michael J; Stiff, Charles L; Lilly, Patrick D; Patskan, George J; Shafer, Kenneth H; Sarkar, Mohamadi A
2016-01-01
While several reports have been published using research methods of estimating exposure risk to e-cigarette vapors in nonusers, only two have directly measured indoor air concentrations from vaping using validated industrial hygiene sampling methodology. Our first study was designed to measure indoor air concentrations of nicotine, menthol, propylene glycol, glycerol, and total particulates during the use of multiple e-cigarettes in a well-characterized room over a period of time. Our second study was a repeat of the first study, and it also evaluated levels of formaldehyde. Measurements were collected using active sampling, near real-time and direct measurement techniques. Air sampling incorporated industrial hygiene sampling methodology using analytical methods established by the National Institute of Occupational Safety and Health and the Occupational Safety and Health Administration. Active samples were collected over a 12-hr period, for 4 days. Background measurements were taken in the same room the day before and the day after vaping. Panelists (n = 185 Study 1; n = 145 Study 2) used menthol and non-menthol MarkTen prototype e-cigarettes. Vaping sessions (six, 1-hr) included 3 prototypes, with total number of puffs ranging from 36-216 per session. Results of the active samples were below the limit of quantitation of the analytical methods. Near real-time data were below the lowest concentration on the established calibration curves. Data from this study indicate that the majority of chemical constituents sampled were below quantifiable levels. Formaldehyde was detected at consistent levels during all sampling periods. These two studies found that indoor vaping of MarkTen prototype e-cigarette does not produce chemical constituents at quantifiable levels or background levels using standard industrial hygiene collection techniques and analytical methods.
NASA Astrophysics Data System (ADS)
Blake, D. R.; Yang, M.; Meinardi, S.; Krauter, C.; Rowland, F. S.
2009-05-01
The San Joaquin Valley Air Pollution Control District of California issued a report identifying dairies as a main source of Volatile Organic Compounds (VOCs). A dairy study funded by the California Air Resources Board commenced shortly after the report was issued. Our University of California Irvine group teamed with California State University Fresno to determine the major sources of VOCs from various dairy operations and from a variety of dairy types. This study identified ethanol and methanol as two gases produced in major quantities throughout the dairies in the San Joaquin valley as by-products of yeast fermentation of silage. Three different types of sampling protocols were employed in order to determine the degree of enhancement of the target oxygenates in the valley air shed. Their sources, emission profiles, and emission rates were determined from whole air samples collected at various locations at the six dairies studied. An assessment of the impact of dairy emissions in the valley was achieved by using data obtained on low altitude NASA DC-8 flights through the valley, and from ground level samples collected though out the valley in a grid like design. Our data suggest that a significant amount of O3 production in the valley may come from methanol, ethanol, and acetaldehyde (a photochemical by-product ethanol oxidation). Our findings indicate that improvement to valley air quality may be obtained by focusing on instituting new silage containment practices and regulations.
(PRESENTED NAQC SAN FRANCISCO, CA) COARSE PM METHODS STUDY: STUDY DESIGN AND RESULTS
Comprehensive field studies were conducted to evaluate the performance of sampling methods for measuring the coarse fraction of PM10 in ambient air. Five separate sampling approaches were evaluated at each of three sampling sites. As the primary basis of comparison, a discrete ...
Combined analysis of job and task benzene air exposures among workers at four US refinery operations
Shin, Jennifer (Mi); Unice, Ken M; Gaffney, Shannon H; Kreider, Marisa L; Gelatt, Richard H; Panko, Julie M
2016-01-01
Workplace air samples analyzed for benzene at four US refineries from 1976 to 2007 were pooled into a single dataset to characterize similarities and differences between job titles, tasks and refineries, and to provide a robust dataset for exposure reconstruction. Approximately 12,000 non-task (>180 min) personal samples associated with 50 job titles and 4000 task (<180 min) samples characterizing 24 tasks were evaluated. Personal air sample data from four individual refineries were pooled based on a number of factors including (1) the consistent sampling approach used by refinery industrial hygienists over time, (2) the use of similar exposure controls, (3) the comparability of benzene content of process streams and end products, (4) the ability to assign uniform job titles and task codes across all four refineries, and (5) our analysis of variance (ANOVA) of the distribution of benzene air concentrations for select jobs/tasks across all four refineries. The jobs and tasks most frequently sampled included those with highest potential contact with refinery product streams containing benzene, which reflected the targeted sampling approach utilized by the facility industrial hygienists. Task and non-task data were analyzed to identify and account for significant differences within job-area, task-job, and task-area categories. This analysis demonstrated that in general, areas with benzene containing process streams were associated with greater benzene air concentrations compared to areas with process streams containing little to no benzene. For several job titles and tasks analyzed, there was a statistically significant decrease in benzene air concentration after 1990. This study provides a job and task-focused analysis of occupational exposure to benzene during refinery operations, and it should be useful for reconstructing refinery workers’ exposures to benzene over the past 30 years. PMID:26862134
Burns, Amanda; Shin, Jennifer Mi; Unice, Ken M; Gaffney, Shannon H; Kreider, Marisa L; Gelatt, Richard H; Panko, Julie M
2017-03-01
Workplace air samples analyzed for benzene at four US refineries from 1976 to 2007 were pooled into a single dataset to characterize similarities and differences between job titles, tasks and refineries, and to provide a robust dataset for exposure reconstruction. Approximately 12,000 non-task (>180 min) personal samples associated with 50 job titles and 4000 task (<180 min) samples characterizing 24 tasks were evaluated. Personal air sample data from four individual refineries were pooled based on a number of factors including (1) the consistent sampling approach used by refinery industrial hygienists over time, (2) the use of similar exposure controls, (3) the comparability of benzene content of process streams and end products, (4) the ability to assign uniform job titles and task codes across all four refineries, and (5) our analysis of variance (ANOVA) of the distribution of benzene air concentrations for select jobs/tasks across all four refineries. The jobs and tasks most frequently sampled included those with highest potential contact with refinery product streams containing benzene, which reflected the targeted sampling approach utilized by the facility industrial hygienists. Task and non-task data were analyzed to identify and account for significant differences within job-area, task-job, and task-area categories. This analysis demonstrated that in general, areas with benzene containing process streams were associated with greater benzene air concentrations compared to areas with process streams containing little to no benzene. For several job titles and tasks analyzed, there was a statistically significant decrease in benzene air concentration after 1990. This study provides a job and task-focused analysis of occupational exposure to benzene during refinery operations, and it should be useful for reconstructing refinery workers' exposures to benzene over the past 30 years.
NASA Astrophysics Data System (ADS)
Rodgers, John C.; Wasiolek, Piotr T.; Schery, Stephen D.; Alcantara, Raul E.
1999-01-01
The need for a continuous air monitor capable of quick and accurate measurements of airborne radioactivity in close proximity to the work environment during waste management, site restoration, and D&D operations led to the Los Alamos National Laboratory development of an environmental continuous air monitor (ECAM). Monitoring the hostile work environment of waste recovery, for example, presents unique challenges for detector design for detectors previously used for the clean room conditions of the typical plutonium laboratory. The environmental and atmospheric conditions (dust, high wind, etc.) influence aerosol particle penetration into the ECAM sampling head as well as the build-up of deposits on the ECAM filter.
An automated atmospheric sampling system operating on 747 airliners
NASA Technical Reports Server (NTRS)
Perkins, P.; Gustafsson, U. R. C.
1975-01-01
An air sampling system that automatically measures the temporal and spatial distribution of selected particulate and gaseous constituents of the atmosphere has been installed on a number of commercial airliners and is collecting data on commercial air routes covering the world. Measurements of constituents related to aircraft engine emissions and other pollutants are made in the upper troposphere and lower stratosphere (6 to 12 km) in support of the Global Air Sampling Program (GASP). Aircraft operated by different airlines sample air at latitudes from the Arctic to Australia. This system includes specialized instrumentation for measuring carbon monoxide, ozone, water vapor, and particulates, a special air inlet probe for sampling outside air, a computerized automatic control, and a data acquisition system. Air constituents and related flight data are tape recorded in flight for later computer processing on the ground.
Birgül, Aşkın; Kurt-Karakus, Perihan Binnur; Alegria, Henry; Gungormus, Elif; Celik, Halil; Cicek, Tugba; Güven, Emine Can
2017-02-01
Polyurethane foam (PUF) passive samplers were employed to assess air concentrations of polychlorinated biphenyls (PCBs) in background, agricultural, semi-urban, urban and industrial sites in Bursa, Turkey. Samplers were deployed for approximately 2-month periods from February to December 2014 in five sampling campaign. Results showed a clear rural-agricultural-semi-urban-urban-industrial PCBs concentration gradient. Considering all sampling periods, ambient air concentrations of Σ 43 PCBs ranged from 9.6 to 1240 pg/m 3 at all sites with an average of 24.1 ± 8.2, 43.8 ± 24.4, 140 ± 190, 42.8 ± 24.6, 160 ± 280, 84.1 ± 105, 170 ± 150 and 280 ± 540 pg/m 3 for Mount Uludag, Uludag University Campus, Camlica, Bursa Technical University Osmangazi Campus, Hamitler, Agakoy, Kestel Organised Industrial District and Demirtas Organised Industrial District sampling sites, respectively. The ambient air PCB concentrations increased along a gradient from background to industrial areas by a factor of 1.7-11.4. 4-Cl PCBs (31.50-81.60%) was the most dominant homologue group at all sampling sites followed by 3-Cl, 7-Cl, 6-Cl and 5-Cl homologue groups. Sampling locations and potential sources grouped in principal component analysis. Results of PCA plots highlighted a large variability of the PCB mixture in air, hence possible related sources, in Bursa area. Calculated inhalation risk levels in this study indicated no serious adverse health effects. This study is one of few efforts to characterize PCB composition in ambient air seasonally and spatially for urban and industrial areas of Turkey by using passive samplers as an alternative sampling method for concurrent monitoring at multiple sites. Copyright © 2016 Elsevier Ltd. All rights reserved.
Measuring HRQoL by comparing the perception of air quality among residents in Selangor
NASA Astrophysics Data System (ADS)
Mohammad, Nor Hazlina; Abdullah, Mohammad Nasir; Razi, Nor Faezah Mohd; Ismail, Adriana
2017-05-01
Most studies regarding to air pollution were focused on forecasting Air Pollutant Index (API). Yet, there were no studies that conducted in Malaysia focused on Health-Related Quality of Life (HRQoL). The aim of this study was to investigate the HRQoL in two urban cities, which are Shah Alam and Putrajaya with different air pollution index. In doing so, SF36v2 questionnaire has been utilized to elicit data on HRQoL domains measured using eight domains (Physical Functioning, Role-Physical, Bodily Pain, General Health, Vitality, Social Functioning, Role-Emotional and Mental Health). A cross-sectional study was conducted and residents were selected using simple random sampling from Shah Alam and Putrajaya. The SF36v2 questionnaire with socio demographic information was distributed to the residents. A total of 266 participated in the study, of which 133 samples per groups. The statistical methods employed were descriptive analyses, independent samples t-test and MANOVA to analyze the HRQoL data. There was no difference in perceptions on HRQoL for Role Physical, Vitality, Social Functioning and Mental Health between residents in Shah Alam and residents in Putrajaya. However, there was difference in perception on HRQoL for Physical Functioning, Bodily Pain, General Health and Role Emotional.
Santos, Juliana Lane Paixão Dos; Bernardi, Angélica Olivier; Pozza Morassi, Letícia L; Silva, Beatriz S; Copetti, Marina Venturini; S Sant'Ana, Anderson
2016-09-01
This study aimed to assess the incidence, to quantify and to assess the diversity of fungi in a multigrain whole meal bread processing plant. Two hundred and eight one (n=281) samples were analyzed, including raw materials (n=120), air samples (n=136) and multigrain breads (n=25). Among the raw materials, the whole corn flour showed the highest counts of fungi (4.8logCFU/g), followed by whole-wheat flour (3.1logCFU/g). The counts of fungi in the air of processing environment were higher in post-baking steps (oven output, cooling, slicing, packaging) than in pre-baking steps (weighing and mixer) (p<0.05). Species of fungi isolated from spoiled bread samples stored at 5, 20, 25 and 30, and 40°C corresponded mostly to Penicillium paneum and Penicillium polonicum isolated from 20 and 24% of samples, respectively. These species were also isolated from raw materials (P. paneum and P. polonicum) and air collected at different processing sampling points (P. polonicum). The high counts of filamentous fungi in raw materials and air samples in processing steps such as cooling, slicing, and packaging, suggest that contamination that may occur in these steps can be critical for the shelf life of breads. The results of this study highlight that the prevention of contamination of breads by fungal spores is still a challenge for bakery industries and that other strategies such as control of germination and growth of spoilage fungi through the development of more stable formulations have to be developed. Copyright © 2016 Elsevier Ltd. All rights reserved.
[Restoration of microbial ammonia oxidizers in air-dried forest soils upon wetting].
Zhou, Xue; Huang, Rong; Song, Ge; Pan, Xianzhang; Jia, Zhongjun
2014-11-04
This study was aimed to investigate the abundance and community shift of ammonia-oxidizing archaea (AOA) and bacteria (AOB) in air-dried forest soils in response to water addition, to explore the applicability of air-dried soil for microbial ecology study, and to elucidate whether AOA within the marine group 1. 1a dominate ammonia oxidizers communities in the acidic forest soils in China. Soil samples were collected from 10 forest sites of the China Ecosystem Research Network (CERN) and kept under air-drying conditions in 2010. In 2013 the air-dried soil samples were adjusted to 60% of soil maximum water holding capacity for a 28-day incubation at 28 degrees C in darkness. DGGE fingerprinting, clone library construction, pyrosequencing and quantitative PCR of amoA genes were performed to assess community change of ammonia oxidizers in air-dried and re-wetted soils. After incubation for 28 days, the abundance of bacteria and archaea increased significantly, up to 3,230 and 568 times, respectively. AOA increased significantly in 8 samples, and AOB increased significantly in 5 of 10 samples. However, pyrosequencing of amoA genes reveals insignificant changes in composition of AOA and AOB communities. Phylogenetic analysis of amoA genes indicates that archaeal ammonia oxidizers were predominated by AOA within the soil group 1. 1b lineage, while the Nitrosospira-like AOB dominate bacteria ammonia oxidizer communities. There was a significantly positive correlation between AOA/AOB ratio and total nitrogen (r2 = 0.54, P < 0.05), implying that soil ammonia oxidation might be dominated by AOA in association with ammonium released from soil mineralization. Phylogenetic analysis suggest that AOA members within the soil group 1. 1b lineage were not restricted to non-acidic soils as previously thought. The abundance rather than composition of AOA and AOB changed in response to water addition. This indicates that air-dried soil could be of help for microbial biogeography study.
HIGH VOLUME INJECTION FOR GCMS ANALYSIS OF PARTICULATE ORGANIC SPECIES IN AMBIENT AIR
Detection of organic species in ambient particulate matter typically requires large air sample volumes, frequently achieved by grouping samples into monthly composites. Decreasing the volume of air sample required would allow shorter collection times and more convenient sample c...
Bouza, E; Peláez, T; Pérez-Molina, J; Marín, M; Alcalá, L; Padilla, B; Muñoz, P; Adán, P; Bové, B; Bueno, M J; Grande, F; Puente, D; Rodríguez, M P; Rodríguez-Créixems, M; Vigil, D; Cuevas, O
2002-12-01
The demolition of a maternity building at our institution provided us with the opportunity to study the load of filamentous fungi in the air. External (nearby streets) and internal (within the hospital buildings) air was sampled with an automatic volumetric machine (MAS-100 Air Samplair) at least daily during the week before the demolition, at 10, 30, 60, 90,120, 180, 240, 420, 540 and 660 min post-demolition, daily during the week after the demolition and weekly during weeks 2, 3 and 4 after demolition. Samples were duplicated to analyse reproducibility. Three hundred and forty samples were obtained: 115 external air, 69 'non-protected' internal air and 156 protected internal air [high efficiency particulate air (HEPA) filtered air under positive pressure]. A significant increase in the colony count of filamentous fungi occurred after the demolition. Median colony counts of external air on demolition day were significantly higher than from internal air (70.2 cfu/m(3) vs 35.8 cfu/m(3)) (P < 0.001). Mechanical demolition on day +4 also produced a significant difference between external and internal air (74.5 cfu/m(3) vs 41.7 cfu/m(3)). The counts returned to baseline levels on day +11. Most areas with a protected air supply yielded no colonies before demolition day and remained negative on demolition day. The reproducibility of the count method was good (intra-assay variance: 2.4 cfu/m(3)). No episodes of invasive filamentous mycosis were detected during the three months following the demolition. Demolition work was associated with a significant increase in the fungal colony counts of hospital external and non-protected internal air. Effective protective measures may be taken to avoid the emergence of clinical infections. Copyright 2002 The Hospital Infection Society
Arbogast, Kristy B; Durbin, Dennis R; Kallan, Michael J; Elliott, Michael R; Winston, Flaura K
2005-04-01
To estimate the risk of serious nonfatal injuries in frontal crashes among belted children seated in the right front seat of vehicles in which second-generation passenger air bags deployed compared with that of belted children seated in the right front seat of vehicles in which first-generation passenger air bags deployed. We enrolled a probability sample of 1781 seat belt-restrained occupants aged 3 through 15 years seated in the right front seat, exposed to deployed passenger air bags in frontal crashes involving insured vehicles in 3 large US regions, between December 1, 1998, and November 30, 2002. A telephone interview was conducted with the driver of the vehicle using a previously validated instrument. The study sample was weighted according to each subject's probability of selection, with analyses conducted on the weighted sample. Main Outcome Measure Risk of serious injury (Abbreviated Injury Scale score of > or =2 injuries and facial lacerations). The risk of serious injury for restrained children in the right front seat exposed to deployed second-generation passenger air bags was 9.9%, compared with 14.9% for similar children exposed to deployed first-generation passenger air bags (adjusted odds ratio, 0.59; 95% confidence interval, 0.36-0.97). This study provides evidence based on field data that the risk of injury to children exposed to deploying second-generation passenger air bags is reduced compared with earlier designs.
Dynamics of airborne fungal populations in a large office building
NASA Technical Reports Server (NTRS)
Burge, H. A.; Pierson, D. L.; Groves, T. O.; Strawn, K. F.; Mishra, S. K.
2000-01-01
The increasing concern with bioaerosols in large office buildings prompted this prospective study of airborne fungal concentrations in a newly constructed building on the Gulf coast. We collected volumetric culture plate air samples on 14 occasions over the 18-month period immediately following building occupancy. On each sampling occasion, we collected duplicate samples from three sites on three floors of this six-story building, and an outdoor sample. Fungal concentrations indoors were consistently below those outdoors, and no sample clearly indicated fungal contamination in the building, although visible growth appeared in the ventilation system during the course of the study. We conclude that modern mechanically ventilated buildings prevent the intrusion of most of the outdoor fungal aerosol, and that even relatively extensive air sampling protocols may not sufficiently document the microbial status of buildings.
NASA Astrophysics Data System (ADS)
Prasetyo, D. J.; Jatmiko, T. H.; Poeloengasih, C. D.; Kismurtono, M.
2017-12-01
In this project, drying kinetic of kidney shape Ganoderma lucidum fruiting body in air circulation system was studied. The drying experiments were conducted at 40, 50 and 60°C with air flow rate of 1.3 ms-1. Samples were weighted periodically until no change in sample weight was recorded, and then the samples were analyzed for its moisture content. Four different thin-layer mathematical models (Newton, Page, Two-term, Midilli) were used and compare to evaluate the drying curves of kidney shape G. lucidum. The water-soluble polysaccharides were evaluated in order to find the best drying temperature condition. The results indicates that Midilli model was the fittest model to describe the characteristic of kidney shape G. lucidum in the air circulation drying system and temperature of 50°C was the best drying condition to get highest value of water-soluble polysaccharides.
NASA Astrophysics Data System (ADS)
Chuang, Jane C.; Mack, Gregory A.; Kuhlman, Michael R.; Wilson, Nancy K.
A pilot field study was performed in Columbus, OH, during the winter of 1986/1987. The objectives were to determine the feasibility of the use of a newly developed quiet sampler in indoor air sampling for particles and semivolatile organic compounds (SVOC) and to measure the concentrations of polycyclic aromatic hydrocarbons (PAH), PAH derivatives, and nicotine in air in selected residences. Eight homes were chosen for sampling on the basis of these characteristics: electric/gas heating system, electric/gas cooking appliances, and the absence/presence of environmental tobacco smoke (ETS). The indoor sampler was equipped with a quartz-fiber filter to collect particles followed by XAD-4 resin to trap SVOC. A PS-1 sampler with a similar sampling module was used outdoors. The indoor air was sampled in the kitchen and living room areas over two consecutive 8-h periods. The outdoor air was sampled concurrently with the indoor samples over a 16-h period. Fifteen PAH, five nitro-PAH, five oxygenated PAH, and three nitrogen heterocyclic compounds were determined in these samples. The most abundant PAH found indoors was naphthalene. The indoor concentrations of PAH derivatives were lower than those of their parent compounds. Average concentrations of all but three target compounds (naphthalene dicarboxylic acid anhydride, pyrene dicarboxylic acid anhydride, and 2-nitrofluoranthene) were higher indoors than outdoors. Environmental tobacco smoke was the most significant influence on indoor pollutant levels. Homes with gas heating systems had higher indoor pollutant levels than homes with electric heating systems. However, the true effects of heating and cooking systems were not characterized as accurately as the effects of ETS because of the small sample sizes and the lack of statistical significance for most pollutant differences in the absence of ETS. The concentrations of PAH marker compounds (phenanthrene, fluoranthene, and pyrene) correlated well with the concentrations of other target compounds. Quinoline and isoquinoline can be used to indicate indoor levels of ETS.
Buttner, M P; Stetzenbach, L D
1993-01-01
Aerobiological monitoring was conducted in an experimental room to aid in the development of standardized sampling protocols for airborne microorganisms in the indoor environment. The objectives of this research were to evaluate the relative efficiencies of selected sampling methods for the retrieval of airborne fungal spores and to determine the effect of human activity on air sampling. Dry aerosols containing known concentrations of Penicillium chrysogenum spores were generated, and air samples were taken by using Andersen six-stage, Surface Air System, Burkard, and depositional samplers. The Andersen and Burkard samplers retrieved the highest numbers of spores compared with the measurement standard, an aerodynamic particle sizer located inside the room. Data from paired samplers demonstrated that the Andersen sampler had the highest levels of sensitivity and repeatability. With a carpet as the source of P. chrysogenum spores, the effects of human activity (walking or vacuuming near the sampling site) on air sampling were also examined. Air samples were taken under undisturbed conditions and after human activity in the room. Human activity resulted in retrieval of significantly higher concentrations of airborne spores. Surface sampling of the carpet revealed moderate to heavy contamination despite relatively low airborne counts. Therefore, in certain situations, air sampling without concomitant surface sampling may not adequately reflect the level of microbial contamination in indoor environments. PMID:8439150
Comparison of coarse coal dust sampling techniques in a laboratory-simulated longwall section.
Patts, Justin R; Barone, Teresa L
2017-05-01
Airborne coal dust generated during mining can deposit and accumulate on mine surfaces, presenting a dust explosion hazard. When assessing dust hazard mitigation strategies for airborne dust reduction, sampling is done in high-velocity ventilation air, which is used to purge the mining face and gallery tunnel. In this environment, the sampler inlet velocity should be matched to the air stream velocity (isokinetic sampling) to prevent oversampling of coarse dust at low sampler-to-air velocity ratios. Low velocity ratios are often encountered when using low flow rate, personal sampling pumps commonly used in underground mines. In this study, with a goal of employing mine-ready equipment, a personal sampler was adapted for area sampling of coarse coal dust in high-velocity ventilation air. This was done by adapting an isokinetic nozzle to the inlet of an Institute of Occupational Medicine (Edinburgh, Scotland) sampling cassette (IOM). Collected dust masses were compared for the modified IOM isokinetic sampler (IOM-MOD), the IOM without the isokinetic nozzle, and a conventional dust sampling cassette without the cyclone on the inlet. All samplers were operated at a flow rate typical of personal sampling pumps: 2 L/min. To ensure differences between collected masses that could be attributed to sampler design and were not influenced by artifacts from dust concentration gradients, relatively uniform and repeatable dust concentrations were demonstrated in the sampling zone of the National Institute for Occupational Safety and Health experimental mine gallery. Consistent with isokinetic theory, greater differences between isokinetic and non-isokinetic sampled masses were found for larger dust volume-size distributions and higher ventilation air velocities. Since isokinetic sampling is conventionally used to determine total dust concentration, and isokinetic sampling made a difference in collected masses, the results suggest when sampling for coarse coal dust the IOM-MOD may improve airborne coarse dust assessments over "off-the-shelf" sampling cassettes.
Comparison of coarse coal dust sampling techniques in a laboratory-simulated longwall section
Patts, Justin R.; Barone, Teresa L.
2017-01-01
Airborne coal dust generated during mining can deposit and accumulate on mine surfaces, presenting a dust explosion hazard. When assessing dust hazard mitigation strategies for airborne dust reduction, sampling is done in high-velocity ventilation air, which is used to purge the mining face and gallery tunnel. In this environment, the sampler inlet velocity should be matched to the air stream velocity (isokinetic sampling) to prevent oversampling of coarse dust at low sampler-to-air velocity ratios. Low velocity ratios are often encountered when using low flow rate, personal sampling pumps commonly used in underground mines. In this study, with a goal of employing mine-ready equipment, a personal sampler was adapted for area sampling of coarse coal dust in high-velocity ventilation air. This was done by adapting an isokinetic nozzle to the inlet of an Institute of Occupational Medicine (Edinburgh, Scotland) sampling cassette (IOM). Collected dust masses were compared for the modified IOM isokinetic sampler (IOM-MOD), the IOM without the isokinetic nozzle, and a conventional dust sampling cassette without the cyclone on the inlet. All samplers were operated at a flow rate typical of personal sampling pumps: 2 L/min. To ensure differences between collected masses that could be attributed to sampler design and were not influenced by artifacts from dust concentration gradients, relatively uniform and repeatable dust concentrations were demonstrated in the sampling zone of the National Institute for Occupational Safety and Health experimental mine gallery. Consistent with isokinetic theory, greater differences between isokinetic and non-isokinetic sampled masses were found for larger dust volume-size distributions and higher ventilation air velocities. Since isokinetic sampling is conventionally used to determine total dust concentration, and isokinetic sampling made a difference in collected masses, the results suggest when sampling for coarse coal dust the IOM-MOD may improve airborne coarse dust assessments over “off-the-shelf” sampling cassettes. PMID:27792474
A Study of Voluntary Turnover of Air Force Officers in Critically-Manned Career Fields
2003-03-01
sampling and the USAF Academy Association of Graduates (AOG). For network sampling, fellow students in the Air Force Institute of Technology (AFIT) were...the voluntary leavers, five independent judges who are graduate students in AFIT will review five random questionnaires and independently...significantly higher levels of emotional exhaustion that did Administrative Assistants and had significantly higher levels of depersonalization than all
Wang, Keran; Wu, Jinyi; Wang, Rui; Yang, Yingying; Chen, Renjie; Maddock, Jay E; Lu, Yuanan
2015-11-15
Shanghai, along with many major cities in China, faces deterioration of air quality and increases in air pollution-related respiratory diseases (RDs) in children due to rapid industrialization and urbanization. The Contingent Valuation Method (CVM) was used to qualitatively and quantitatively measure the willingness to pay (WTP) for reducing children's RDs through air quality improvement. Between April and May, 2014, 975 face-to-face interviews were collected from parents in a community-based and a hospital-setting in Shanghai. Multiple imputation and the Probit model were used to determine the relationship between the WTP and the related environmental factors, child health factors and the socio-economic status. Most respondents reported being willing to make a financial contribution to improve air quality in both the community (52.6%) and hospital (70.2%) samples. Those in the hospital setting were willing to pay significantly more ¥504 (USD$80.7) compared to the community sample ¥428 ($68.5) as expected. Reasons for those not being willing to pay included lack of disposable income and believing that responsibility of the air quality was a community issue. These did not differ by sample. Annual household income and education were related to WTP. This study indicated that parents in Shanghai would be willing to pay for improved air quality. Children's health can be the incentive for the citizens' participation and support in the air quality improvement, therefore, hospital settings may present unique places to improve education about air quality and enhance advocacy efforts. This study also suggested that future environmental policies be addressed more rigorously for targeted populations. Copyright © 2015 Elsevier B.V. All rights reserved.
Carter Carburetor Weekly Air Monitoring & Sampling Report - March 7, 2013 - March 13, 2016
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
The Mechanistic Indicators of Childhood Asthma (MICA) study in Detroit, Michigan introduced a participant-based approach to reduce the resource burden associated with collection of indoor and outdoor residential air sampling data. A subset of participants designated as MICA-Air c...
The impact of air pollution from the coal-fired Columbia Generating Station upon vegetation was investigated. Air monitoring of 03 and 02 documented levels that occurred before and with operation of the generating station. Field sampling of alfalfa, lichens, and white pines was u...
Lai, I-Chien; Lee, Chon-Lin; Ko, Fung-Chi; Lin, Ju-Chieh; Huang, Hu-Ching; Shiu, Ruei-Feng
2017-07-15
The air-water exchange is important for determining the transport, fate, and chemical loading of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere and in aquatic systems. Investigations of PAH air-water exchange are mostly based on observational data obtained using complicated field sampling processes. This study proposes a new approach to improve the estimation of long-term PAH air-water exchange fluxes by using a multivariate regression model to simulate hourly gaseous PAH concentrations. Model performance analysis and the benefits from this approach indicate its effectiveness at improving the flux estimations and at decreasing the field sampling difficulty. The proposed GIS mapping approach is useful for box model establishment and is tested for visualization of the spatiotemporal variations of air-water exchange fluxes in a coastal zone. The air-water exchange fluxes illustrated by contour maps suggest that the atmospheric PAHs might have greater impacts on offshore sites than on the coastal area in this study. Copyright © 2017 Elsevier Ltd. All rights reserved.
Air sampling workshop: October 24-25, 1978
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1979-06-01
A two-day workshop was held in October 1978 on air sampling strategies for the occupational environment. Strategies comprise the elements of implementing an air sampling program including deciding on the extent of sampling, selecting appropriate types of measurement, placing sampling instruments properly, and interpreting sample results correctly. All of these elements are vital in the reliable assessment of occupational exposures yet their coverage in the industrial hygiene literature is meager. Although keyed to a few introductory topics, the agenda was sufficiently informal to accommodate extemporaneous discussion on any subject related to sampling strategies. Questions raised during the workshop mirror themore » status of air sampling strategy as much as the factual information that was presented. It may be concluded from the discussion and questions that air sampling strategy is an elementary state and urgently needs concerted attention from the industrial hygiene profession.« less
An automated atmospheric sampling system operating on 747 airliners
NASA Technical Reports Server (NTRS)
Perkins, P. J.; Gustafsson, U. R. C.
1976-01-01
An air sampling system that automatically measures the temporal and spatial distribution of particulate and gaseous constituents of the atmosphere is collecting data on commercial air routes covering the world. Measurements are made in the upper troposphere and lower stratosphere (6 to 12 km) of constituents related to aircraft engine emissions and other pollutants. Aircraft operated by different airlines sample air at latitudes from the Arctic to Australia. This unique system includes specialized instrumentation, a special air inlet probe for sampling outside air, a computerized automatic control, and a data acquisition system. Air constituent and related flight data are tape recorded in flight for later computer processing on the ground.
Trajkovska, S; Mbaye, M; Gaye Seye, M D; Aaron, J J; Chevreuil, M; Blanchoud, H
2009-06-01
A detailed toxicological study on several pesticides, including chlorothalonil, cyprodynil, dichlobénil, pendimethaline, trifluraline, and alpha-endosulfan, present at trace levels in air and total atmospheric precipitations of Paris is presented. The pesticides contained in the atmospheric samples, collected during sampling campaigns in February-March 2007, are identified and quantified by a high-performance liquid chromatographic (HPLC)-UV detection method. The toxicity measurements are performed by means of the Microtox bioluminescence method, based on the evaluation of the bioluminescence inhibition of the Vibrio fischeri marine bacteria at two exposure times to the pesticide solutions. The specific toxicity, corresponding to the particular toxicity of the compound under study and represented by the EC(50) parameter, is determined for these pesticides. Also, the global toxicity, which is the toxicity of all micro-pollutants present in the sample under study, is estimated for the extracts of air and atmospheric precipitation (rainwater) samples. The specific toxicities strongly vary with the nature of the pesticide, the EC(50) parameter values being comprised between 0.17 and 0.83 mg/mL and 0.15 and 0.66 mg/mL, respectively, for exposure times of 5 and 15 min. The importance of the atmospheric samples' global toxicity and the respective contribution of the toxic potency of the various pesticides contained in these samples are discussed.
NASA Technical Reports Server (NTRS)
Wallace, William T.; Limero, Thomas F.; Gazda, Daniel B.; Macatangay, Ariel V.; Dwivedi, Prabha; Fernandez, Facundo M.
2014-01-01
In the history of manned spaceflight, environmental monitoring has relied heavily on archival sampling. For short missions, this type of sample collection was sufficient; returned samples provided a snapshot of the presence of chemical and biological contaminants in the spacecraft air and water. However, with the construction of the International Space Station (ISS) and the subsequent extension of mission durations, soon to be up to one year, the need for enhanced, real-time environmental monitoring became more pressing. The past several years have seen the implementation of several real-time monitors aboard the ISS, complemented with reduced archival sampling. The station air is currently monitored for volatile organic compounds (VOCs) using gas chromatography-differential mobility spectrometry (Air Quality Monitor [AQM]). The water on ISS is analyzed to measure total organic carbon and biocide concentrations using the Total Organic Carbon Analyzer (TOCA) and the Colorimetric Water Quality Monitoring Kit (CWQMK), respectively. The current air and water monitors provide important data, but the number and size of the different instruments makes them impractical for future exploration missions. It is apparent that there is still a need for improvements in environmental monitoring capabilities. One such improvement could be realized by modifying a single instrument to analyze both air and water. As the AQM currently provides quantitative, compound-specific information for target compounds present in air samples, and many of the compounds are also targets for water quality monitoring, this instrument provides a logical starting point to evaluate the feasibility of this approach. In this presentation, we will discuss our recent studies aimed at determining an appropriate method for introducing VOCs from water samples into the gas phase and our current work, in which an electro-thermal vaporization unit has been interfaced with the AQM to analyze target analytes at the relevant concentrations at which they are routinely detected in archival water samples from the ISS.
NASA Technical Reports Server (NTRS)
Fetzer, Eric J.; Lambrigtsen, Bjorn H.; Eldering, Annmarie; Aumann, Hartmut H.; Chahine, Moustafa T.
2006-01-01
We examine differences in total precipitable water vapor (PWV) from the Atmospheric Infrared Sounder (AIRS) and the Advanced Microwave Scanning Radiometer (AMSR-E) experiments sharing the Aqua spacecraft platform. Both systems provide estimates of PWV over water surfaces. We compare AIRS and AMSR-E PWV to constrain AIRS retrieval uncertainties as functions of AIRS retrieved infrared cloud fraction. PWV differences between the two instruments vary only weakly with infrared cloud fraction up to about 70%. Maps of AIRS-AMSR-E PWV differences vary with location and season. Observational biases, when both instruments observe identical scenes, are generally less than 5%. Exceptions are in cold air outbreaks where AIRS is biased moist by 10-20% or 10-60% (depending on retrieval processing) and at high latitudes in winter where AIRS is dry by 5-10%. Sampling biases, from different sampling characteristics of AIRS and AMSR-E, vary in sign and magnitude. AIRS sampling is dry by up to 30% in most high-latitude regions but moist by 5-15% in subtropical stratus cloud belts. Over the northwest Pacific, AIRS samples conditions more moist than AMSR-E by a much as 60%. We hypothesize that both wet and dry sampling biases are due to the effects of clouds on the AIRS retrieval methodology. The sign and magnitude of these biases depend upon the types of cloud present and on the relationship between clouds and PWV. These results for PWV imply that climatologies of height-resolved water vapor from AIRS must take into consideration local meteorological processes affecting AIRS sampling.
PM2.5 and aerosol black carbon in Suva, Fiji
NASA Astrophysics Data System (ADS)
Isley, C. F.; Nelson, P. F.; Taylor, M. P.; Mani, F. S.; Maata, M.; Atanacio, A.; Stelcer, E.; Cohen, D. D.
2017-02-01
Concentrations of particulate air pollution in Suva, Fiji, have been largely unknown and consequently, current strategies to reduce health risk from air pollution in Suva are not targeted effectively. This lack of air quality data is common across the Pacific Island Countries. A monitoring study, during 2014 and 2015, has characterised the fine particulate air quality in Suva, representing the most detailed study to date of fine aerosol air pollutants for the Pacific Islands; with sampling at City, Residential (Kinoya) and Background (Suva Point) sites. Meteorology for Suva, as it relates to pollutant dispersion for this period of time, has also been analysed. The study design enables the contribution of maritime air and the anthropogenic emissions to be carefully distinguished from each other and separately characterised. Back trajectory calculations show that a packet of air sampled at the Suva City site has typically travelled 724 km in the 24-h prior to sampling, mainly over open ocean waters; inferring that pollutants would also be rapidly transported away from Suva. For fine particulates, Suva City reported a mid-week PM2.5 of 8.6 ± 0.4 μg/m3, averaged over 13-months of gravimetric sampling. Continuous monitoring (Osiris laser photometer) suggests that some areas of Suva may experience levels exceeding the WHO PM2.5 guideline of 10 μg/m3, however, compared to other countries, Fiji's PM2.5 is low. Peak aerosol particulate levels, at all sites, were experienced at night-time, when atmospheric conditions were least favourable to dispersion of air pollutants. Suva's average ambient concentrations of black carbon in PM2.5, 2.2 ± 0.1 μg/m3, are, however, similar to those measured in much larger cities. With any given parcel of air spending only seven minutes, on average, over the land area of Suva Peninsula, these black carbon concentrations are indicative that significant combustion emissions occur within Suva. Many other communities in the Pacific Islands, as well as in Africa, Asia and South America share similar climate and similar burning practices and as such are likely to experience similar aerosol black carbon loadings. These black carbon levels indicate the need for combustion emissions, particularly those from open burning and diesel usage, to be addressed in air policy.
40 CFR 86.537-90 - Dynamometer test runs.
Code of Federal Regulations, 2014 CFR
2014-07-01
... “transient” formaldehyde exhaust sample, the “transient” dilution air sample bag, the “transient” methanol... start “transient” exhaust and dilution air bag samples to the analytical system and process the samples... Section 86.537-90 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...
40 CFR 86.537-90 - Dynamometer test runs.
Code of Federal Regulations, 2012 CFR
2012-07-01
... “transient” formaldehyde exhaust sample, the “transient” dilution air sample bag, the “transient” methanol... start “transient” exhaust and dilution air bag samples to the analytical system and process the samples... Section 86.537-90 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...
40 CFR 86.537-90 - Dynamometer test runs.
Code of Federal Regulations, 2013 CFR
2013-07-01
... “transient” formaldehyde exhaust sample, the “transient” dilution air sample bag, the “transient” methanol... start “transient” exhaust and dilution air bag samples to the analytical system and process the samples... Section 86.537-90 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...
Unique risk and protective factors for partner aggression in a large scale air force survey.
Slep, Amy M Smith; Foran, Heather M; Heyman, Richard E; Snarr, Jeffery D
2010-08-01
The objective of this study is to examine risk factors of physical aggression against a partner in a large representative Active Duty Air Force sample. A stratified sample of 128,950 United States Active Duty members were invited to participate in an Air Force-wide anonymous online survey across 82 bases. The final sample (N = 52,780) was weighted to be representative of the United States Air Force. Backward stepwise regression analyses were conducted to identify unique predictors of partner physical aggression perpetration within and across different ecological levels (individual, family, organization, and community levels). Relationship satisfaction, alcohol problems, financial stress, and number of years in the military were identified as unique predictors of men's and women's perpetration of violence against their partner across ecological levels. Parental status, support from neighbors, personal coping, and support from formal agencies also uniquely predicted men's but not women's perpetration of violence across ecological levels. This study identified specific risk factors of partner violence that may be targeted by prevention and intervention efforts aimed at different levels of impact (e.g., family interventions, community-wide programs).
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 9 2012-07-01 2012-07-01 false Air sampling. 61.34 Section 61.34 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.34 Air...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 9 2013-07-01 2013-07-01 false Air sampling. 61.34 Section 61.34 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium § 61.34 Air...
Carter Carburetor Weekly Air Monitoring & Sampling Report - November 30, 2015 – December 6, 2015
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Carter Carburetor Weekly Air Monitoring & Sampling Report - October 26, 2015 – November 1, 2015
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Carter Carburetor Weekly Air Monitoring & Sampling Report - February 15, 2016 – February 21, 2016
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Carter Carburetor Weekly Air Monitoring & Sampling Report - October 12, 2015 – October 18, 2015
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Carter Carburetor Weekly Air Monitoring & Sampling Report - November 23, 2015 – November 29, 2015
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Carter Carburetor Weekly Air Monitoring & Sampling Report - October 5, 2015 – October 11, 2015
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Carter Carburetor Weekly Air Monitoring & Sampling Report - February 1, 2016 – February 7, 2016
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Carter Carburetor Weekly Air Monitoring & Sampling Report - September 28, 2015 – October 4, 2015
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Carter Carburetor Weekly Air Monitoring & Sampling Report - November 16, 2015 – November 22, 2015
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Carter Carburetor Weekly Air Monitoring & Sampling Report - November 9, 2015 – November 15, 2015
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Carter Carburetor Weekly Air Monitoring & Sampling Report - October 19, 2015 – October 25, 2015
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Carter Carburetor Weekly Air Monitoring & Sampling Report - November 2, 2015 – November 8, 2015
Carter Carburetor Daily Weather Conditions, Dairly Work Activities, Daily Air Monitoring and Samplying Results, Air Monitoring/Samplying Results –Station 2 Linc 126, Air Monitoring/Sampling Results- Sation 3 Linc 123, Air Monitoring/Samplying Results-Stati
Fekadu, Samuel; Getachewu, Bahilu
2015-04-01
Hospital environment represents a congenial situation where microorganisms and susceptible patients are indoors together. Thus, the objective of this study is to provide fundamental data related to the microbial quality of indoor air of Jimma University Specialized Hospital wards, to estimate the health hazard and to create standards for indoor air quality control. The microbial quality of indoor air of seven wards of Jimma University Specialized Hospital was determined. Passive air sampling technique, using open Petri-dishes containing different culture media, was employed to collect sample twice daily. The concentrations of bacteria and fungi aerosols in the indoor environment of the wards ranged between 2123 - 9733 CFU/m(3). The statistical analysis showed that the concentrations of bacteria that were measured in all studied wards were significantly different from each other (p-value=0.017), whereas the concentrations of fungi that were measured in all sampled wards were not significantly different from each other (p-value=0.850). Moreover, the concentrations of bacteria that were measured at different sampling time (morning and afternoon) were significantly different (p-value =0.001). All wards that were included in the study were heavily contaminated with bacteria and fungi. Thus, immediate interventions are needed to control those environmental factors which favor the growth and multiplication of microbes, and it is vital to control visitors and students in and out the wards. Moreover, it is advisable that strict measures be put in place to check the increasing microbial load in the hospital environment.
ERIC Educational Resources Information Center
1999
This document contains four symposium papers on enhancing employee skills. "The Effect of Study Skills Training Intervention on United States Air Force Aeromedical Apprentices" (John C. Griffith) demonstrates how study skills intervention resulted in a significant increase in the end-of-course scores of a sample of 90 randomly selected Air Force…
Evaluation of membrane filter field monitors for microbiological air sampling
NASA Technical Reports Server (NTRS)
Fields, N. D.; Oxborrow, G. S.; Puleo, J. R.; Herring, C. M.
1974-01-01
Due to area constraints encountered in assembly and testing areas of spacecraft, the membrane filter field monitor (MF) and the National Aeronautics and Space Administration-accepted Reyniers slit air sampler were compared for recovery of airborne microbial contamination. The intramural air in a microbiological laboratory area and a clean room environment used for the assembly and testing of the Apollo spacecraft was studied. A significantly higher number of microorganisms was recovered by the Reyniers sampler. A high degree of consistency between the two sampling methods was shown by a regression analysis, with a correlation coefficient of 0.93. The MF samplers detected 79% of the concentration measured by the Reyniers slit samplers. The types of microorganisms identified from both sampling methods were similar.
30 CFR 90.205 - Approved sampling devices; operation; air flowrate.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved sampling devices; operation; air... LABOR COAL MINE SAFETY AND HEALTH MANDATORY HEALTH STANDARDS-COAL MINERS WHO HAVE EVIDENCE OF THE DEVELOPMENT OF PNEUMOCONIOSIS Sampling Procedures § 90.205 Approved sampling devices; operation; air flowrate...
Analysis of EPA and DOE WIPP Air Sampling Data
During the April 2014 EPA visit to WIPP, EPA co-located four ambient air samplers with existing Department of Energy (DOE) ambient air samplers to independently corroborate DOE's reported air sampling results.
Can car air filters be useful as a sampling medium for air pollution monitoring purposes?
Katsoyiannis, Athanasios; Birgul, Askin; Ratola, Nuno; Cincinelli, Alessandra; Sweetman, Andy J; Jones, Kevin C
2012-11-01
Urban air quality and real human exposure to chemical environmental stressors is an issue of high scientific and political interest. In an effort to find innovative and inexpensive means for air quality monitoring, the ability of car engine air filters (CAFs) to act as efficient samplers collecting street level air, to which people are exposed to, was tested. In particular, in the case of taxis, air filters are replaced after regular distances, the itineraries are almost exclusively urban, cruising mode is similar and, thus, knowledge of the air flow can provide with an integrated city air sample. The present pilot study focused on polycyclic aromatic hydrocarbons (PAHs), the most important category of organic pollutants associated with traffic emissions. Concentrations of ΣPAHs in CAFs ranged between 650 and 2900 μg CAF(-1), with benzo[b]fluoranthene, benzo[k]fluoranthene and indeno[123-cd]pyrene being the most abundant PAHs. Benzo[a]pyrene (BaP) ranged between 110 and 250 μg CAF(-1), accounting regularly for 5-15% of the total carcinogenic PAHs. The CAF PAH loads were used to derive road-level atmospheric PAH concentrations from a standard formula relating to the CAF air flow. Important parameters/assumptions for these estimates are the cruising speed and the exposure duration of each CAF. Based on information obtained from the garage experts, an average 'sampled air volume' of 48,750 m(3) per CAF was estimated, with uncertainty in this calculation estimated to be about a factor of 4 between the two extreme scenarios. Based on this air volume, ΣPAHs ranged between 13 and 56 ng m(-3) and BaP between 2.1 and 5.0 ng m(-3), suggesting that in-traffic BaP concentrations can be many times higher than the limit values set by the UK (0.25 ng m(-3)) and the European Union (1.0 ng m(-3)), or from active sampling stations normally cited on building roof tops or far from city centres. Notwithstanding the limitations of this approach, the very low cost, the continuous availability of very high amounts of "sample", and the "retroactivity" render it very useful and complementary to existing passive sampling techniques. This approach yields estimated air concentrations that reflect the pollutant concentrations to which taxi drivers, pedestrians, cyclists and road-related professionals are exposed. Copyright © 2012 Elsevier Ltd. All rights reserved.
[Biological contamination in office buildings related to ventilation/air conditioning system].
Bródka, Karolina; Sowiak, Małgorzata; Kozajda, Anna; Cyprowski, Marcin; Irena, Szadkowska-Stańczyk
2012-01-01
Indoor air is contaminated with microorganisms coming from both the atmospheric air and sources present in premises. The aim of this study was to analyze the concentrations of biological agents in office buildings, dependending on ventilation/air conditioning system and season. The study covered office buildings (different in the system of ventila-tion/air conditioning). Air samples for assessing the levels of inhalable dust, endotoxins and (1-->3)-beta-D-glucans, were taken at the selected stationary points of each building during summer and winter. The air was sampled for 6 h, using portable sets consisting of the GilAir 5 pump and the head filled with a filter of fiber glass. The samples for the presence of airborne bacteria and fungi were collected twice during the day using the impaction method. Average concentrations of inhalable dust, bacteria, fungi, endotoxins and (1-->3)-beta-D-glucans in office premises were 0.09 mg/m3, 6.00 x 10(2) cfu/m3, 4.59 x 10(1) cfu/m3, 0.42 ng/m3 and 3.91 ng/m3, respectively. Higher concentrations of the investigated agents were found in summer. In premises with air conditioning concentrations of airborne fungi, (1-->3)-beta-D-glucans and inhalable dust were significantly lower in winter. In summer the trend was reverse except for (1-->3)-beta-D-glucans. Concentrations of biological agents were affected by the season and the presence of air conditioning. Concentrations of inhalable dust, bacteria, fungi, endotoxins and (1-->3)-beta-D-glucans, observed inside the office buildings, were significantly higher in summer than in winter. The presence of the air conditioning system modified in various ways the levels of biological agents. Its influence was greater on the concentration of fungi and (1-->3)-beta-D-glucans than on that of bacteria and endotoxins.
NASA Astrophysics Data System (ADS)
Ghosh, B.
2016-12-01
Hydrocarbons can be emitted into the atmosphere from various sources and play a crucial role in local and regional air quality through formation of secondary pollutants such as ozone and particulate matter. Understanding their sources and their potential air quality impact is essential for effective environmental policymaking. A ground based ambient air measurement campaign was conducted in February-March of 2016 at the Phillips 66 Research Center in Northeastern Oklahoma to study ambient hydrocarbons in the region, understand their sources, as well as estimate their air quality impact. This study is a follow-up to a study conducted during the same time in 2015 and aims to understand the variation of hydrocarbons levels in ambient air over time and the corresponding air quality impact. Various trace gases were measured using a suite of instrumentation. Non-methane hydrocarbons (NMHCs) were sampled using two-hour time integrated whole air sampling. A total of 375 air samples were collected during the study and were analyzed offline with GC-MS (Agilent) following cold-trap dehydration (Entech Instruments). In addition, higher time resolution measurement of methane, ethane, CO, CO2, N2O, and H2O was achieved by a 1Hz Dual QCL Monitor (Aerodyne) along with a 0.1 Hz ozone monitor (2B Technologies). Levels of methane of 7 ppm and above were observed in this study. Among NMHCs, C2-C5 alkanes were the most dominant with their mean concentrations ranging from 1.9 to 17 ppb (Figure 1). Chemical tracers (ethane, propane, ethyne, CO) and isomeric ratios (i-C5/ n-C5) suggest that oil and gas production activity probably was the source of hydrocarbon emissions measured in this study. Photochemical age was determined using hydrocarbon ratios and its significance will be discussed. While the 2016 winter was warmer compared to 2015, overall levels of NMHCs are higher in 2016 compared to 2015 and have a different distribution in mixing ratios. The results from 2016 study will be compared with 2015 results.1Significance of these emissions on local air quality will also be discussed. Reference Buddhadeb Ghosh, Volatile Organic Compound Emissions from Oil and Gas Production Sources: A Pilot Study in Northeastern Oklahoma AGU Fall Meeting 2015, https://agu.confex.com/agu/fm15/meetingapp.cgi/Paper/59445
Bohlin, Pernilla; Audy, Ondřej; Škrdlíková, Lenka; Kukučka, Petr; Vojta, Šimon; Přibylová, Petra; Prokeš, Roman; Čupr, Pavel; Klánová, Jana
2014-11-01
Indoor air pollution has been recognized as an important risk factor for human health, especially in areas where people tend to spend most of their time indoors. Many semi-volatile organic compounds (SVOCs) have primarily indoor sources and are present in orders of magnitude higher concentrations indoors than outdoors. Despite this, awareness of SVOCs in indoor air and assessment of the link between indoor concentrations and human health have lagged behind those of outdoor air. This is partially related to challenges associated with indoor sampling of SVOCs. Passive air samplers (PASs), which are widely accepted in established outdoor air monitoring networks, have been used to fill the knowledge gaps on indoor SVOCs distribution. However, their applicability for indoor environments and the assessment of human health risks lack sufficient experimental data. To address this issue, we performed an indoor calibration study of polyurethane foam (PUF) PAS deployed in a double-dome chamber, covering both legacy and new SVOC classes. PUF-PAS and a continuous low-volume active air sampler (AAS) were co-deployed for a calibration period of twelve weeks. Based on the results from this evaluation, PUF-PAS in a double-bowl chamber is recommended for indoor sampling and health risk assessment of gas phase SVOCs, including novel brominated flame retardants (nBFR) providing sufficient exposure time is applied. Data for particle associated SVOCs suffered from significant uncertainties caused by low level of detection and low precision in this study. A more open chamber design for indoor studies may allow for higher sampling rates (RS) and better performance for the particle associated SVOCs.
[Microbiological quality of the air in "small gastronomy point"].
Wójcik-Stopczyńska, Barbara
2006-01-01
The aim of this work was the estimation of microbial contamination of the air in "small gastronomy point". The study included three places, which have been separated on the ground of their function: 1. area of subsidiaries, 2. area of distribution (sale and serving meal), 3. area of consumption. The total numbers of aerobic mesophilic bacteria, yeasts and moulds were determined by sedimentation method. Taxonomy units of fungal aerosol were also estimated. The samples of air were collected in 16 investigation points in the morning (8-8.30) and in the afternoon (14-14.30). Four series of measurements were carried out and in general 128 of air samples were tested. The results showed that numbers of bacteria, yeasts and moulds were variable and received respectively 30-3397, 0-254 and 0-138 cfu x m(-3). Microbial contamination of air changed depending on area character (the highest average count of bacteria occurred in the air of consumption area and fungi in subsidiaries area), time of a day (contamination of the air increased in the afternoon) and determination date. Only in single samples the numbers of bacteria and fungi were higher than recommended level. Pigmentary bacteria had high participation in total count of bacteria and filamentous fungi were represented mostly by Penicillium sp. and Cladosporium sp.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schneider, J.F.; O`Neill, H.J.; Raphaelian, L.A.
1995-03-01
The US Army`s Aberdeen Proving Ground has been a test site for a variety of munitions, including chemical warfare agents (CWA). The Pilot Plant Complex (PPC) at Aberdeen was the site of development, manufacture, storage, and disposal of CWA. Deterioration of the buildings and violations of environmental laws led to closure of the complex in 1986. Since that time, all equipment, piping, and conduit in the buildings have been removed. The buildings have been declared free of surface CWA contamination as a result of air sampling using the military system. However, no air sampling has been done to determine ifmore » other hazardous volatile organic compounds are present in the PPC, although a wide range of toxic and/or hazardous materials other than CWA was used in the PPC. The assumption has been that the air in the PPC is not hazardous. The purpose of this air-monitoring study was to screen the indoor air in the PPC to confirm the assumption that the air does not contain volatile organic contaminants at levels that would endanger persons in the buildings. A secondary purpose was to identify any potential sources of volatile organic contaminants that need to be monitored in subsequent sampling efforts.« less
Atmospheric particulate measurements in Norfolk, Virginia
NASA Technical Reports Server (NTRS)
Storey, R. W., Jr.; Sentell, R. J.; Woods, D. C.; Smith, J. R.; Harris, F. S., Jr.
1975-01-01
Characterization of atmospheric particulates was conducted at a site near the center of Norfolk, Virginia. Air quality was measured in terms of atmospheric mass loading, particle size distribution, and particulate elemental composition for a period of 2 weeks. The objectives of this study were (1) to establish a mean level of air quality and deviations about this mean, (2) to ascertain diurnal changes or special events in air quality, and (3) to evaluate instrumentation and sampling schedules. Simultaneous measurements were made with the following instruments: a quartz crystal microbalance particulate monitor, a light-scattering multirange particle counter, a high-volume air sampler, and polycarbonate membrane filters. To assess the impact of meteorological conditions on air quality variations, continuous data on temperature, relative humidity, wind speed, and wind direction were recorded. Particulate elemental composition was obtained from neutron activation and scanning electron microscopy analyses of polycarbonate membrane filter samples. The measured average mass loading agrees reasonably well with the mass loadings determined by the Virginia State Air Pollution Control Board. There are consistent diurnal increases in atmospheric mass loading in the early morning and a sample time resolution of 1/2 hour seems necessary to detect most of the significant events.
Ishikawa, Tetsuo; Sorimachi, Atsuyuki; Arae, Hideki; Sahoo, Sarata Kumar; Janik, Miroslaw; Hosoda, Masahiro; Tokonami, Shinji
2014-02-18
Several studies have estimated inhalation doses for the public because of the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. Most of them were based on measurement of radioactivity in outdoor air and included the assumption that people stayed outdoors all day. Although this assumption gives a conservative estimate, it is not realistic. The "air decontamination factor" (ratio of indoor to outdoor air radionuclide concentrations) was estimated from simultaneous sampling of radioactivity in both inside and outside air of one building. The building was a workplace and located at the National Institute of Radiological Sciences (NIRS) in Chiba Prefecture, Japan. Aerosol-associated radioactive materials in air were collected onto filters, and the filters were analyzed by γ spectrometry at NIRS. The filter sampling was started on March 15, 2011 and was continued for more than 1 year. Several radionuclides, such as (131)I, (134)Cs, and (137)Cs were found by measuring the filters with a germanium detector. The air decontamination factor was around 0.64 for particulate (131)I and 0.58 for (137)Cs. These values could give implications for the ratio of indoor to outdoor radionuclide concentrations after the FDNPP accident for a similar type of building.
NASA Astrophysics Data System (ADS)
Zhao, Xiangai; He, Miao; Shang, Haibo; Yu, Hongling; Wang, Hao; Li, Huijie; Piao, Jingyi; Quinto, Maurizio; Li, Donghao
2018-05-01
Studies on seasonal distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) in Salix matsudana leaves covering its annual life cycle were carried out in order to evaluate plant leaf response sensitivity to air pollution. Salix matsudana leaves were collected throughout different development phases of plant leaf inclusive of bud break to fallen leaves, covering from spring (May) to autumn (November). Simultaneously, particle and gas samples were collected using a high volume air sampler. Seven different PAHs were determined simultaneously in these samples. The temperature dependence of the partitioning of PAHs in air and plant leaves was investigated and the results were incorporated into a mathematical model. The measured plant/air partition coefficients have been found to be exponentially proportional to the reciprocal temperature, in agreement with theoretical expectations. Furthermore, in order to define the influence of different parameters on PAH adsorption on plant leaves, area and lipid leaf content were also measured. Results demonstrated that temperature plays a very important role in PAHs partitioning and that this value should be carefully considered during sampling, in order to obtain the best correlation between PAHs concentration in air and leaves.
Su, Yushan; Hung, Hayley; Stern, Gary; Sverko, Ed; Lao, Randy; Barresi, Enzo; Rosenberg, Bruno; Fellin, Phil; Li, Henrik; Xiao, Hang
2011-11-01
Initiated in 1992, air monitoring of organic pollutants in the Canadian Arctic provided spatial and temporal trends in support of Canada's participation in the Stockholm Convention of Persistent Organic Pollutants. The specific analytical laboratory charged with this task was changed in 2002 while field sampling protocols remained unchanged. Three rounds of intensive comparison studies were conducted in 2004, 2005, and 2008 to assess data comparability between the two laboratories. Analysis was compared for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in standards, blind samples of mixed standards and extracts of real air samples. Good measurement accuracy was achieved for both laboratories when standards were analyzed. Variation of measurement accuracy over time was found for some OCPs and PCBs in standards on a random and non-systematic manner. Relatively low accuracy in analyzing blind samples was likely related to the process of sample purification. Inter-laboratory measurement differences for standards (<30%) and samples (<70%) were generally less than or comparable to those reported in a previous inter-laboratory study with 21 participating laboratories. Regression analysis showed inconsistent data comparability between the two laboratories during the initial stages of the study. These inter-laboratory differences can complicate abilities to discern long-term trends of pollutants in a given sampling site. It is advisable to maintain long-term measurements with minimal changes in sample analysis.
Influence of relative humidity on VOC concentrations in indoor air.
Markowicz, Pawel; Larsson, Lennart
2015-04-01
Volatile organic compounds (VOCs) may be emitted from surfaces indoors leading to compromised air quality. This study scrutinized the influence of relative humidity (RH) on VOC concentrations in a building that had been subjected to water damage. While air samplings in a damp room at low RH (21-22%) only revealed minor amounts of 2-ethylhexanol (3 μg/m(3)) and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (TXIB, 8 μg/m(3)), measurements performed after a rapid increase of RH (to 58-75%) revealed an increase in VOC concentrations which was 3-fold for 2-ethylhexanol and 2-fold for TXIB. Similar VOC emission patterns were found in laboratory analyses of moisture-affected and laboratory-contaminated building materials. This study demonstrates the importance of monitoring RH when sampling indoor air for VOCs in order to avoid misleading conclusions from the analytical results.
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. Englebrecht; I. Kavouras; D. Campbell
2008-08-01
The Desert Research Institute (DRI) is performing a scoping study as part of the U.S. Department of Energy's Yucca Mountain Environmental Monitoring Systems Initiative (EMSI). The main objective is to obtain baseline air quality information for Yucca Mountain and an area surrounding the Nevada Test Site (NTS). Air quality and meteorological monitoring and sampling equipment housed in a mobile trailer (shelter) is collecting data at eight sites outside the NTS, including Ash Meadows National Wildlife Refuge (NWR), Beatty, Sarcobatus Flats, Rachel, Caliente, Pahranagat NWR, Crater Flat, and Tonopah Airport, and at four sites on the NTS (Engelbrecht et al., 2007a-d).more » The trailer is stationed at any one site for approximately eight weeks at a time. This letter report provides a summary of air quality and meteorological data, on completion of the site's sampling program.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. Englebrecht; I. Kavouras; D. Campbell
2008-08-01
The Desert Research Institute (DRI) is performing a scoping study as part of the U.S. Department of Energy's Yucca Mountain Environmental Monitoring Systems Initiative (EMSI). The main objective is to obtain baseline air quality information for Yucca Mountain and an area surrounding the Nevada Test Site (NTS). Air quality and meteorological monitoring and sampling equipment housed in a mobile trailer (shelter) is collecting data at eight sites outside the NTS, including Ash Meadows National Wildlife Refuge (NWR), Pahranagat NWR, Beatty, Rachel, Caliente, Crater Flat, and Tonopah Airport, and at four sites on the NTS (Engelbrecht et al., 2007a-d). The trailermore » is stationed at any one site for approximately eight weeks at a time. This letter report provides a summary of air quality and meteorological data on completion of the site's sampling program.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. Engelbrecht; I. Kavouras; D. Campbell
2009-04-02
The Desert Research Institute (DRI) is performing a scoping study as part of the U.S. Department of Energy's Yucca Mountain Environmental Monitoring Systems Initiative (EMSI). The main objective is to obtain baseline air quality information for Yucca Mountain and an area surrounding the Nevada Test Site (NTS). Air quality and meteorological monitoring and sampling equipment housed in a mobile trailer (shelter) is collecting data at eight sites outside the NTS, including Ash Meadows National Wildlife Refuge (NWR), Pahranagat NWR, Beatty, Rachel, Caliente, Crater Flat, and Tonopah Airport, and at four sites on the NTS (Engelbrecht et al., 2007a-d). The trailermore » is stationed at any one site for approximately eight weeks at a time. This letter report provides a summary of air quality and meteorological data on completion of the site's sampling program.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. Engelbrecht; I. Kavouras; D. Campbell
2009-04-02
The Desert Research Institute (DRI) is performing a scoping study as part of the U.S. Department of Energy's Yucca Mountain Environmental Monitoring Systems Initiative (EMSI). The main objective is to obtain baseline air quality information for Yucca Mountain and an area surrounding the Nevada Test Site (NTS). Air quality and meteorological monitoring and sampling equipment housed in a mobile trailer (shelter) is collecting data at eight sites outside the NTS, including Ash Meadows National Wildlife Refuge (NWR), Beatty, Sarcobatus Flats, Rachel, Caliente, Pahranagat NWR, Crater Flat, and Tonopah Airport, and at four sites on the NTS (Engelbrecht et al., 2007a-d).more » The trailer is stationed at any one site for approximately eight weeks at a time. This letter report provides a summary of air quality and meteorological data, on completion of the site's sampling program.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. Engelbrecht; I. Kavouras; D. Campbell
2009-04-02
The Desert Research Institute (DRI) is performing a scoping study as part of the U.S. Department of Energy's Yucca Mountain Environmental Monitoring Systems Initiative (EMSI). The main objective is to obtain baseline air quality information for Yucca Mountain and an area surrounding the Nevada Test Site (NTS). Air quality and meteorological monitoring and sampling equipment housed in a mobile trailer (shelter) is collecting data at eight sites outside the NTS, including Ash Meadows National Wildlife Refuge (NWR), Tonopah Airport, Beatty, Rachel, Caliente, Pahranagat NWR, Crater Flat, and the Tonopah Airport, and at four sites on the NTS (Engelbrecht et al.,more » 2007a-d). The trailer is stationed at any one site for approximately eight weeks at a time. This letter report provides a summary of air quality and meteorological data, on completion of the site's sampling program.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. Engelbrecht; I. Kavouras; D Campbell
2008-08-01
The Desert Research Institute (DRI) is performing a scoping study as part of the U.S. Department of Energy's Yucca Mountain Environmental Monitoring Systems Initiative (EMSI). The main objective is to obtain baseline air quality information for Yucca Mountain and an area surrounding the Nevada Test Site (NTS). Air quality and meteorological monitoring and sampling equipment housed in a mobile trailer (shelter) is collecting data at eight sites outside the NTS, including Ash Meadows National Wildlife Refuge (NWR), Tonopah Airport, Beatty, Rachel, Caliente, Pahranagat NWR, Crater Flat, and the Tonopah Airport, and at four sites on the NTS (Engelbrecht et al.,more » 2007a-d). The trailer is stationed at any one site for approximately eight weeks at a time. This letter report provides a summary of air quality and meteorological data, on completion of the site's sampling program.« less
Decomposition Odour Profiling in the Air and Soil Surrounding Vertebrate Carrion
2014-01-01
Chemical profiling of decomposition odour is conducted in the environmental sciences to detect malodourous target sources in air, water or soil. More recently decomposition odour profiling has been employed in the forensic sciences to generate a profile of the volatile organic compounds (VOCs) produced by decomposed remains. The chemical profile of decomposition odour is still being debated with variations in the VOC profile attributed to the sample collection technique, method of chemical analysis, and environment in which decomposition occurred. To date, little consideration has been given to the partitioning of odour between different matrices and the impact this has on developing an accurate VOC profile. The purpose of this research was to investigate the decomposition odour profile surrounding vertebrate carrion to determine how VOCs partition between soil and air. Four pig carcasses (Sus scrofa domesticus L.) were placed on a soil surface to decompose naturally and their odour profile monitored over a period of two months. Corresponding control sites were also monitored to determine the VOC profile of the surrounding environment. Samples were collected from the soil below and the air (headspace) above the decomposed remains using sorbent tubes and analysed using gas chromatography-mass spectrometry. A total of 249 compounds were identified but only 58 compounds were common to both air and soil samples. This study has demonstrated that soil and air samples produce distinct subsets of VOCs that contribute to the overall decomposition odour. Sample collection from only one matrix will reduce the likelihood of detecting the complete spectrum of VOCs, which further confounds the issue of determining a complete and accurate decomposition odour profile. Confirmation of this profile will enhance the performance of cadaver-detection dogs that are tasked with detecting decomposition odour in both soil and air to locate victim remains. PMID:24740412
Decomposition odour profiling in the air and soil surrounding vertebrate carrion.
Forbes, Shari L; Perrault, Katelynn A
2014-01-01
Chemical profiling of decomposition odour is conducted in the environmental sciences to detect malodourous target sources in air, water or soil. More recently decomposition odour profiling has been employed in the forensic sciences to generate a profile of the volatile organic compounds (VOCs) produced by decomposed remains. The chemical profile of decomposition odour is still being debated with variations in the VOC profile attributed to the sample collection technique, method of chemical analysis, and environment in which decomposition occurred. To date, little consideration has been given to the partitioning of odour between different matrices and the impact this has on developing an accurate VOC profile. The purpose of this research was to investigate the decomposition odour profile surrounding vertebrate carrion to determine how VOCs partition between soil and air. Four pig carcasses (Sus scrofa domesticus L.) were placed on a soil surface to decompose naturally and their odour profile monitored over a period of two months. Corresponding control sites were also monitored to determine the VOC profile of the surrounding environment. Samples were collected from the soil below and the air (headspace) above the decomposed remains using sorbent tubes and analysed using gas chromatography-mass spectrometry. A total of 249 compounds were identified but only 58 compounds were common to both air and soil samples. This study has demonstrated that soil and air samples produce distinct subsets of VOCs that contribute to the overall decomposition odour. Sample collection from only one matrix will reduce the likelihood of detecting the complete spectrum of VOCs, which further confounds the issue of determining a complete and accurate decomposition odour profile. Confirmation of this profile will enhance the performance of cadaver-detection dogs that are tasked with detecting decomposition odour in both soil and air to locate victim remains.
2013-01-01
Background The efficiency of recovery and the detection limit of Legionella after co-culture with Acanthamoeba polyphaga are not known and so far no investigations have been carried out to determine the efficiency of the recovery of Legionella spp. by co-culture and compare it with that of conventional culturing methods. This study aimed to assess the detection limits of co-culture compared to culture for Legionella pneumophila in compost and air samples. Compost and air samples were spiked with known concentrations of L. pneumophila. Direct culturing and co-culture with amoebae were used in parallel to isolate L. pneumophila and recovery standard curves for both methods were produced for each sample. Results The co-culture proved to be more sensitive than the reference method, detecting 102-103 L. pneumophila cells in 1 g of spiked compost or 1 m3 of spiked air, as compared to 105-106 cells in 1 g of spiked compost and 1 m3 of spiked air. Conclusions Co-culture with amoebae is a useful, sensitive and reliable technique to enrich L. pneumophila in environmental samples that contain only low amounts of bacterial cells. PMID:23442526
DOE Office of Scientific and Technical Information (OSTI.GOV)
Broman, D.; Axelman, J.; Bandh, C.
In order to study the fate and occurrence of two groups of hydrophobic compounds in the Baltic aquatic environment a large number of samples were collected from the southern Baltic proper to the northern Bothnian Bay for the analyses of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs). The following sample matrices were collected; bottom surface sediments (0--1 cm, collected with gravity corer), settling particulate matter (collected with sediment traps), open water samples and over water samples (suspended particulates and dissolved fraction sampled by filtration) and air samples (aerosols and vapor phase sampled by filtration). All samples (except over watermore » and air) were collected at open sea in the Baltic. The analyses results have been used to make a model approach on the whole Baltic and to elucidate different aspects of the behavior of PAHs and PCBs in the Baltic, such as the occurrence of the compounds in water and sediment, the total content as well as the concentration variabilities over such a large geographical area, Further, the data on settling particulate matter as well as the air concentration data were used to estimate the total fluxes of PAHs and PCBs to the bottoms of the Baltic and t o the total water area of the Baltic, respectively. Further, data on the PAH and PCB content in river water from four major rivers provides rough estimates of the riverine input to the Baltic. The dynamics of PAHs and PCBs within the water mass have also been studied in terms of settling velocities and residence times in the water mass for these type of compounds in the open Baltic.« less
Eom, In-Yong; Risticevic, Sanja; Pawliszyn, Janusz
2012-02-24
Air in a room infested by Cimex lectularius L. (Hemiptera: Cimicidae) was sampled simultaneously by three different sampling devices including solid phase microextraction (SPME) fiber coatings, thin film microextraction (TFME) devices, and needle trap devices (NTDs) and then analyzed by gas chromatography-mass spectrometry (GC-MS). The main focus of this study was to fully characterize indoor air by identifying compounds extracted by three different microextraction formats and, therefore, perform both the device comparison and more complete characterization of C. lectularius pheromone. The NTD technique was capable of extracting both (E)-2-hexenal and (E)-2-octenal, which were previously identified as alarm pheromones of bedbugs, and superior NTD recoveries for these two components allowed reliable identification based on mass spectral library searching and linear temperature programmed retention index (LTPRI) technique. While the use of DVB/CAR/PDMS SPME fiber coatings provided complementary sample fingerprinting and profiling results, TFME sampling devices provided discriminative extraction coverage toward highly volatile analytes. In addition to two alarm pheromones, relative abundances of all other analytes were recorded for all three devices and aligned across all examined samples, namely, highly infested area, less infested area, and control samples which were characterized by different bedbug populations. The results presented in the current study illustrate comprehensive characterization of infested indoor air samples through the use of three different non-invasive SPME formats and identification of novel components comprising C. lectularius pheromone, therefore, promising future alternatives for use of potential synthetic pheromones for detection of infestations. Copyright © 2011 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Panko, Julie M.; Chu, Jennifer; Kreider, Marisa L.; Unice, Ken M.
2013-06-01
In addition to industrial facilities, fuel combustion, forest fires and dust erosion, exhaust and non-exhaust vehicle emissions are an important source of ambient air respirable particulate matter (PM10). Non-exhaust vehicle emissions are formed from wear particles of vehicle components such as brakes, clutches, chassis and tires. Although the non-exhaust particles are relatively minor contributors to the overall ambient air particulate load, reliable exposure estimates are few. In this study, a global sampling program was conducted to quantify tire and road wear particles (TRWP) in the ambient air in order to understand potential human exposures and the overall contribution of these particles to the PM10. The sampling was conducted in Europe, the United States and Japan and the sampling locations were selected to represent a variety of settings including both rural and urban core; and within each residential, commercial and recreational receptors. The air samples were analyzed using validated chemical markers for rubber polymer based on a pyrolysis technique. Results indicated that TRWP concentrations in the PM10 fraction were low with averages ranging from 0.05 to 0.70 μg m-3, representing an average PM10 contribution of 0.84%. The TRWP concentration in air was associated with traffic load and population density, but the trend was not statistically significant. Further, significant differences across days were not observed. This study provides a robust dataset to understand potential human exposures to airborne TRWP.
Kuyper, Brett; Labuschagne, Casper; Philibert, Raïssa; Moyo, Nicholas; Waldron, Howard; Reason, Chris; Palmer, Carl
2012-01-01
Wherever measurements have been made bromoform was found to be ubiquitous in the surface ocean in pmolar-nmolar concentrations. These measurements show concentrations in coastal regions orders of magnitude higher than in the pelagic oceans. Its atmospheric presence is primarily due to its release from algae and rapid transport to the marine boundary troposphere where it is known to participate in ozone chemistry via photochemical and catalytic pathways. Until quite recently, a limited number of studies existed (compared to other marine volatile organic compounds (VOCs)), mainly due to the analytical challenge(s) presented by the low environmental mixing ratios. In this work we detail the development of a simplified, cost effective method to detect and quantify bromoform in environmental air samples. Air samples (1.5 L) were preconcentrated onto a precooled adsorbent (Carbopack X/Carboxen 1016) trap. These samples were injected by means of rapid thermal desorption for separation and detection by GC-ECD. The system was calibrated by means of a custom-built permeation oven. A linear system response was achieved, having a detection limit of 0.73 ± 0.09 ppt. A range of environmental samples was analysed to demonstrate the ability of the technique to separate and identify bromoform from air samples. The results showed that bromoform concentrations typically averaged 24.7 ± 17.3 ppt in marine air samples, 68.5 ± 26.3 ppt in Cape Town urban air samples and 33.9 ± 40.5 ppt in simulated biomass burning plumes (SBBP). PMID:23202011
The Lagrangian method provides estimates of the chemical and physical evolution of air arriving in the daytime boundary layer at Baltimore. Study results indicate a dominant role for regional transport contributions of those days when sulfate air pollution is highest in Baltimor...
The purpose of this SOP is to describe the in-field use of the modified Air Sentinel. Samples collected with this Hi-Vol instrument were analyzed for atmospheric concentrations of target metals. This procedure was followed to ensure consistent data retrieval of air and dust ana...
Barnett, J Matthew; Yu, Xiao-Ying; Recknagle, Kurtis P; Glissmeyer, John A
2016-11-01
A planned laboratory space and exhaust system modification to the Pacific Northwest National Laboratory Material Science and Technology Building indicated that a new evaluation of the mixing at the air sampling system location would be required for compliance to ANSI/HPS N13.1-2011. The modified exhaust system would add a third fan, thereby increasing the overall exhaust rate out the stack, thus voiding the previous mixing study. Prior to modifying the radioactive air emissions exhaust system, a three-dimensional computational fluid dynamics computer model was used to evaluate the mixing at the sampling system location. Modeling of the original three-fan system indicated that not all mixing criteria could be met. A second modeling effort was conducted with the addition of an air blender downstream of the confluence of the three fans, which then showed satisfactory mixing results. The final installation included an air blender, and the exhaust system underwent full-scale tests to verify velocity, cyclonic flow, gas, and particulate uniformity. The modeling results and those of the full-scale tests show agreement between each of the evaluated criteria. The use of a computational fluid dynamics code was an effective aid in the design process and allowed the sampling system to remain in its original location while still meeting the requirements for sampling at a well mixed location.
Mawn, Michael P; Kurtz, Kristine; Stahl, Deborah; Chalfant, Richard L; Koban, Mary E; Dawson, Barbara J
2013-01-01
A new low global warming refrigerant, 2,3,3,3-tetrafluoro propene, or HFO-1234yf, has been successfully evaluated for automotive air conditioning, and is also being evaluated for stationary refrigeration and air conditioning systems. Due to the advantageous environmental properties of HFO-1234yf versus HFC-134a, coupled with its similar physical properties and system performance, HFO-1234yf is also being evaluated to replace HFC-134a in refrigeration applications where neat HFC-134a is currently used. This study reports on the development and validation of a sampling and analytical method for the determination of HFO-1234yf in air. Different collection media were screened for desorption and simulated sampling efficiency with three-section (350/350/350 mg) Anasorb CSC showing the best results. Therefore, air samples were collected using two 3-section Anasorb CSC sorbent tubes in series at 0.02 L/min for up to 8 hr for sample volumes of up to 9.6 L. The sorbent tubes were extracted in methylene chloride, and analyzed by gas chromatography with flame ionization detection. The method was validated from 0.1× to 20× the target level of 0.5 ppm (2.3 mg/m(3)) for a 9.6 L air volume. Desorption efficiencies for HFO-1234yf were 88 to 109% for all replicates over the validation range with a mean overall recovery of 93%. Simulated sampling efficiencies ranged from 87 to 104% with a mean of 94%. No migration or breakthrough to the back tube was observed under the sampling conditions evaluated. HFO-1234yf samples showed acceptable storage stability on Anasorb CSC sorbent up to a period of 30 days when stored under ambient, refrigerated, or frozen temperature conditions.
Ryan, Laura; O'Mara, Niall; Tansey, Sana; Slattery, Tom; Hanahoe, Belinda; Vellinga, Akke; Doyle, Maeve; Cormican, Martin
2018-05-01
Immunocompromised patients are at risk of invasive fungal infection. These high-risk patients are nursed in protective isolation to reduce the risk of nosocomial aspergillosis while in hospital-ideally in a positive pressure single room with high-efficiency particulate air filtration. However, neutral pressure rooms are a potential alternative, especially for patients requiring both protective and source isolation. This study examined mold and bacterial concentrations in air samples from positive and neutral pressure rooms to assess whether neutral pressure rooms offer a similar environment to that of positive pressure rooms in terms of mold concentrations in the air. Mold concentrations were found to be similar in the positive and neutral pressure room types examined in this study. These results add to the paucity of literature in this area. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Fitzgerald, J Edward F; Malik, Momin; Ahmed, Irfan
2012-02-01
Surgical smoke containing potentially carcinogenic and irritant chemicals is an inevitable consequence of intraoperative energized dissection. Different energized dissection methods have not been compared directly in human laparoscopic surgery or against commonly encountered pollutants. This study undertook an analysis of carcinogenic and irritant volatile hydrocarbon concentrations in electrocautery and ultrasonic scalpel plumes compared with cigarette smoke and urban city air control samples. Once ethical approval was obtained, gas samples were aspirated from the peritoneal cavity after human laparoscopic intraabdominal surgery solely using either electrocautery or ultrasonic scalpels. All were adsorbed in Tenax tubes and concentrations of carcinogenic or irritant volatile hydrocarbons measured by gas chromatography. The results were compared with cigarette smoke and urban city air control samples. The analyzing laboratory was blinded to sample origin. A total of 10 patients consented to intraoperative gas sampling in which only one method of energized dissection was used. Six carcinogenic or irritant hydrocarbons (benzene, ethylbenzene, styrene, toluene, heptene, and methylpropene) were identified in one or more samples. With the exception of styrene (P = 0.016), a nonsignificant trend toward lower hydrocarbon concentrations was observed with ultrasonic scalpel use. Ultrasonic scalpel plumes had significantly lower hydrocarbon concentrations than cigarette smoke, with the exception of methylpropene (P = 0.332). No significant difference was observed with city air. Electrocautery samples contained significantly lower hydrocarbon concentrations than cigarette smoke, with the exception of toluene (P = 0.117) and methyl propene (P = 0.914). Except for toluene (P = 0.028), city air showed no significant difference. Both electrocautery and ultrasonic dissection are associated with significantly lower concentrations of the most commonly detected carcinogenic and irritant hydrocarbons than cigarette smoke. A nonsignificant trend toward lower hydrocarbon concentrations was seen with ultrasonic scalpel dissection compared with diathermy. The contamination levels in city air were largely comparable with those seen after ultrasonic scalpel use. Although hydrocarbon concentrations are low, cumulative exposures may increase health risks. Where concerns arise, ultrasonic scalpel dissection may be preferable.
NASA Technical Reports Server (NTRS)
Park, A.; Dominek, A. K.
1990-01-01
Constitutive parameter extraction from S parameter data using a rectangular waveguide whose cross section is partially filled with a material sample as opposed to being completely filled was examined. One reason for studying a partially filled geometry is to analyze the effect of air gaps between the sample and fixture for the extraction of constitutive parameters. Air gaps can occur in high temperature parameter measurements when the sample was prepared at room temperature. Single port and two port measurement approaches to parameter extraction are also discussed.
Kettleson, E; Kumar, S; Reponen, T; Vesper, S; Méheust, D; Grinshpun, S A; Adhikari, A
2013-10-01
Respiratory illnesses have been linked to children's exposures to water-damaged homes. Therefore, understanding the microbiome in water-damaged homes is critical to preventing these illnesses. Few studies have quantified bacterial contamination, especially specific species, in water-damaged homes. We collected air and dust samples in twenty-one low-mold homes and twenty-one high-mold homes. The concentrations of three bacteria/genera, Stenotrophomonas maltophilia, Streptomyces sp., and Mycobacterium sp., were measured in air and dust samples using quantitative PCR (QPCR). The concentrations of the bacteria measured in the air samples were not associated with any specific home characteristic based on multiple regression models. However, higher concentrations of S. maltophilia in the dust samples were associated with water damage, that is, with higher floor surface moisture and higher concentrations of moisture-related mold species. The concentrations of Streptomyces and Mycobacterium sp. had similar patterns and may be partially determined by human and animal occupants and outdoor sources of these bacteria. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Detection of cocaine in cargo containers by high-volume vapor sampling: field test at Port of Miami
NASA Astrophysics Data System (ADS)
Neudorfl, Pavel; Hupe, Michael; Pilon, Pierre; Lawrence, Andre H.; Drolet, Gerry; Su, Chih-Wu; Rigdon, Stephen W.; Kunz, Terry D.; Ulwick, Syd; Hoglund, David E.; Wingo, Jeff J.; Demirgian, Jack C.; Shier, Patrick
1997-02-01
The use of marine containers is a well known smuggling method for large shipments of drugs. Such containers present an ideal method of smuggling as the examination method is time consuming, difficult and expensive for the importing community. At present, various methods are being studied for screening containers which would allow to rapidly distinguish between innocent and suspicious cargo. Air sampling is one such method. Air is withdrawn for the inside of containers and analyzed for telltale vapors uniquely associated with the drug. The attractive feature of the technique is that the containers could be sampled without destuffing and opening, since air could be conveniently withdrawn via ventilation ducts. In the present paper, the development of air sampling methodology for the detection of cocaine hydrochloride will be discussed, and the results from a recent field test will be presented. The results indicated that vapors of cocaine and its decomposition product, ecgonidine methyl ester, could serve as sensitive indicators of the presence of the drug in the containers.
Chamber Bioaerosol Study: Outdoor Air and Human Occupants as Sources of Indoor Airborne Microbes
Adams, Rachel I.; Bhangar, Seema; Pasut, Wilmer; Arens, Edward A.; Taylor, John W.; Lindow, Steven E.; Nazaroff, William W.; Bruns, Thomas D.
2015-01-01
Human occupants are an important source of microbes in indoor environments. In this study, we used DNA sequencing of filter samples to assess the fungal and bacterial composition of air in an environmental chamber under different levels of occupancy, activity, and exposed or covered carpeting. In this office-like, mechanically ventilated environment, results showed a strong influence of outdoor-derived particles, with the indoor microbial composition tracking that of outdoor air for the 2-hour sampling periods. The number of occupants and their activity played a significant but smaller role influencing the composition of indoor bioaerosols. Human-associated taxa were observed but were not particularly abundant, except in the case of one fungus that appeared to be transported into the chamber on the clothing of a study participant. Overall, this study revealed a smaller signature of human body-associated taxa than had been expected based on recent studies of indoor microbiomes, suggesting that occupants may not exert a strong influence on bioaerosol microbial composition in a space that, like many offices, is well ventilated with air that is moderately filtered and moderately occupied. PMID:26024222
NHEXAS PHASE I REGION 5 STUDY--QA ANALYTICAL RESULTS FOR VOCS IN REPLICATES
This data set includes analytical results for measurements of VOCs in 204 duplicate (replicate) samples. Measurements were made for up to 23 VOCs in samples of air, water, and blood. Duplicate samples (samples collected along with or next to the original samples) were collected t...
NHEXAS PHASE I REGION 5 STUDY--QA ANALYTICAL RESULTS FOR METALS IN REPLICATES
This data set includes analytical results for measurements of metals in 490 duplicate (replicate) samples and for particles in 130 duplicate samples. Measurements were made for up to 11 metals in samples of air, dust, water, blood, and urine. Duplicate samples (samples collected ...
NASA Technical Reports Server (NTRS)
1977-01-01
Samples of liquid oxygen, high pressure nitrogen, low pressure nitrogen, and missile grade air were studied to determine the hydrocarbon concentrations. Concentration of the samples was achieved by adsorption on a molecular sieve and activated charcoal. The trapped hydrocarbons were then desorbed and transferred to an analytical column in a gas chromatograph. The sensitivity of the method depends on the volume of gas passed through the adsorbent tubes. The value of the method was verified through recoverability and reproducibility studies. The use of this method enables LOX, GN2, and missile grade air systems to be routinely monitored to determine low level increases in specific hydrocarbon concentration that could lead to potentially hazardous conditions.
Huang, Yumei; Li, Jun; Xu, Yue; Xu, Weihai; Cheng, Zhineng; Liu, Junwen; Wang, Yan; Tian, Chongguo; Luo, Chunling; Zhang, Gan
2014-03-15
Nineteen pairs of air and seawater samples collected from the equatorial Indian Ocean onboard the Shiyan I from 4/2011 to 5/2011 were analyzed for PCBs and HCB. Gaseous concentrations of ∑(ICES)PCBs (ICES: International Council for the Exploration of the Seas) and HCB were lower than previous data over the study area. Air samples collected near the coast had higher levels of PCBs relative to those collected in the open ocean, which may be influenced by proximity to source regions and air mass origins. Dissolved concentrations of ∑(ICES)PCBs and HCB were 1.4-14 pg L⁻¹ and 0.94-13 pg L⁻¹, with the highest concentrations in the sample collected from Strait of Malacca. Fugacity fractions suggest volatilization of PCBs and HCB from the seawater to air during the cruise, with fluxes of 0.45-34 ng m⁻² d⁻¹ and 0.36-18 ng m⁻² d⁻¹, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.
Quantitative assessment of bio-aerosols contamination in indoor air of University dormitory rooms.
Hayleeyesus, Samuel Fekadu; Ejeso, Amanuel; Derseh, Fikirte Aklilu
2015-07-01
The purpose of this study is to provide insight into how students are exposed to indoor bio-aerosols in the dormitory rooms and to figure out the major possible factors that govern the contamination levels. The Bio-aerosols concentration level of indoor air of thirty dormitory rooms of Jimma University was determined by taking 120 samples. Passive air sampling technique; the settle plate method using open Petri-dishes containing different culture media was employed to collect sample twice daily. The range of bio-aerosols contamination detected in the dormitory rooms was 511-9960 CFU/m(3) for bacterial and 531-6568 CFU/m(3) for fungi. Based on the criteria stated by WHO expert group, from the total 120 samples 95 of the samples were above the recommended level. The statistical analysis showed that, occupancy were significantly affected the concentrations of bacteria that were measured in all dormitory rooms at 6:00 am sampling time (p-value=0.000) and also the concentrations of bacteria that were measured in all dormitory rooms were significantly different to each other (p-value=0.013) as of their significance difference in occupancy (p-value=0.000). Moreover, there were a significant different on the contamination level of bacteria at 6:00 am and 7:00 pm sampling time (p=0.015), whereas there is no significant difference for fungi contamination level for two sampling times (p= 0.674). There is excessive bio-aerosols contaminant in indoor air of dormitory rooms of Jimma University and human occupancy produces a marked concentration increase of bacterial contamination levels and most fungi species present into the rooms air of Jimma University dormitory were not human-borne.
Quantitative assessment of bio-aerosols contamination in indoor air of University dormitory rooms
Hayleeyesus, Samuel Fekadu; Ejeso, Amanuel; Derseh, Fikirte Aklilu
2015-01-01
Objectives The purpose of this study is to provide insight into how students are exposed to indoor bio-aerosols in the dormitory rooms and to figure out the major possible factors that govern the contamination levels. Methodology The Bio-aerosols concentration level of indoor air of thirty dormitory rooms of Jimma University was determined by taking 120 samples. Passive air sampling technique; the settle plate method using open Petri-dishes containing different culture media was employed to collect sample twice daily. Results The range of bio-aerosols contamination detected in the dormitory rooms was 511–9960 CFU/m3 for bacterial and 531–6568 CFU/m3 for fungi. Based on the criteria stated by WHO expert group, from the total 120 samples 95 of the samples were above the recommended level. The statistical analysis showed that, occupancy were significantly affected the concentrations of bacteria that were measured in all dormitory rooms at 6:00 am sampling time (p-value=0.000) and also the concentrations of bacteria that were measured in all dormitory rooms were significantly different to each other (p-value=0.013) as of their significance difference in occupancy (p-value=0.000). Moreover, there were a significant different on the contamination level of bacteria at 6:00 am and 7:00 pm sampling time (p=0.015), whereas there is no significant difference for fungi contamination level for two sampling times (p= 0.674). Conclusion There is excessive bio-aerosols contaminant in indoor air of dormitory rooms of Jimma University and human occupancy produces a marked concentration increase of bacterial contamination levels and most fungi species present into the rooms air of Jimma University dormitory were not human-borne. PMID:26609289
Garrison, R A; Robertson, L D; Koehn, R D; Wynn, S R
1993-12-01
Commercial air duct sanitation services are advertised to the public as being effective in reducing indoor aeroallergen levels despite the absence of published supporting data. Eight residential heat-ventilation-air conditioning (HVAC) systems in six homes and seven HVAC systems in five homes in winter and summer, respectively, were sampled to determine fungal colony forming units (CFUs) prior to and after an HVAC sanitation procedure was performed by a local company. Two houses in which no sanitation procedure was performed served as controls in each study phase. Two sample sets were obtained at each HVAC system prior to cleaning in order to determine baseline CFU levels. The test HVAC systems were then cleaned, and the HVAC systems allowed to operate as desired by the residents. Posttreatment sampling was performed 48 hours and then weekly after cleaning for 8 weeks. The HVAC systems were analyzed by exposing sterile 2% malt extract media plates at a 90-degree angle to the air flow at the air supply and air return vents. The baseline CFUs were similar in the control and study houses. Eight weeks after sanitation, the study houses demonstrated an overall CFU reduction of 92% during winter and 84% during summer. No reduction in CFU values was observed over the 8-week study period for the houses selected as controls. Further, HVAC sanitation appeared to reduce the number of fungal colonies entering and leaving the HVAC system, suggesting that the HVAC contained a significant percentage of the total fungal load in these homes. These data suggest that HVAC sanitation may be an effective tool in reducing airborne fungal populations in residential environments.
Woolfenden, Elizabeth
2010-04-16
Sorbent tubes/traps are widely used in combination with gas chromatographic (GC) analytical methods to monitor the vapour-phase fraction of organic compounds in air. Target compounds range in volatility from acetylene and freons to phthalates and PCBs and include apolar, polar and reactive species. Airborne vapour concentrations will vary depending on the nature of the location, nearby pollution sources, weather conditions, etc. Levels can range from low percent concentrations in stack and vent emissions to low part per trillion (ppt) levels in ultra-clean outdoor locations. Hundreds, even thousands of different compounds may be present in any given atmosphere. GC is commonly used in combination with mass spectrometry (MS) detection especially for environmental monitoring or for screening uncharacterised workplace atmospheres. Given the complexity and variability of organic vapours in air, no one sampling approach suits every monitoring scenario. A variety of different sampling strategies and sorbent media have been developed to address specific applications. Key sorbent-based examples include: active (pumped) sampling onto tubes packed with one or more sorbents held at ambient temperature; diffusive (passive) sampling onto sorbent tubes/cartridges; on-line sampling of air/gas streams into cooled sorbent traps; and transfer of air samples from containers (canisters, Tedlar) bags, etc.) into cooled sorbent focusing traps. Whichever sampling approach is selected, subsequent analysis almost always involves either solvent extraction or thermal desorption (TD) prior to GC(/MS) analysis. The overall performance of the air monitoring method will depend heavily on appropriate selection of key sampling and analytical parameters. This comprehensive review of air monitoring using sorbent tubes/traps is divided into 2 parts. (1) Sorbent-based air sampling option. (2) Sorbent selection and other aspects of optimizing sorbent-based air monitoring methods. The paper presents current state-of-the-art and recent developments in relevant areas such as sorbent research, sampler design, enhanced approaches to analytical quality assurance and on-tube derivatisation. Copyright 2009 Elsevier B.V. All rights reserved.
Ackelsberg, Joel; Leykam, Frederic M; Hazi, Yair; Madsen, Larry C; West, Todd H; Faltesek, Anthony; Henderson, Gavin D; Henderson, Christopher L; Leighton, Terrance
2011-09-01
Native air sampling (NAS) is distinguished from dedicated air sampling (DAS) devices (eg, BioWatch) that are deployed to detect aerosol disseminations of biological threat agents. NAS uses filter samples from heating, ventilation, and air conditioning (HVAC) systems in commercial properties for environmental sampling after DAS detection of biological threat agent incidents. It represents an untapped, scientifically sound, efficient, widely distributed, and comparably inexpensive resource for postevent environmental sampling. Calculations predict that postevent NAS would be more efficient than environmental surface sampling by orders of magnitude. HVAC filter samples could be collected from pre-identified surrounding NAS facilities to corroborate the DAS alarm and delineate the path taken by the bioaerosol plume. The New York City (NYC) Native Air Sampling Pilot Project explored whether native air sampling would be acceptable to private sector stakeholders and could be implemented successfully in NYC. Building trade associations facilitated outreach to and discussions with property owners and managers, who expedited contact with building managers of candidate NAS properties that they managed or owned. Nominal NAS building requirements were determined; procedures to identify and evaluate candidate NAS facilities were developed; data collection tools and other resources were designed and used to expedite candidate NAS building selection and evaluation in Manhattan; and exemplar environmental sampling playbooks for emergency responders were completed. In this sample, modern buildings with single or few corporate tenants were the best NAS candidate facilities. The Pilot Project successfully demonstrated that in one urban setting a native air sampling strategy could be implemented with effective public-private collaboration.
NASA Technical Reports Server (NTRS)
James, John T.
2001-01-01
The toxicological assessment of air samples returned at the end of the STS-l04 (7 A) flight to the ISS is reported. ISS air samples were taken in June and July 2001 from the Service Module, FGB, and U.S. Laboratory using grab sample canisters (GSCs) and/or formaldehyde badges. Preflight and end-of-mission samples were obtained from Atlantis using GSCs. Solid sorbent air sampler (SSAS) samples were obtained from the ISS in April, June, and July. Analytical methods have not changed from earlier reports, and all quality control measures were met.
Electron Spectroscopy for Chemical Analysis (ESCA) study of atmospheric particles
NASA Technical Reports Server (NTRS)
Dillard, J. G.; Seals, R. D.; Wightman, J. P.
1979-01-01
The results of analyses by ESCA (Electron Spectroscopy for Chemical Analysis) on several Nuclepore filters which were exposed during air pollution studies are presented along with correlative measurements by Neutron Activation Analysis and Scanning Electron Microscopy. Samples were exposed during air pollution studies at Norfolk, Virginia and the NASA Kennedy Space Center (KSC). It was demonstrated that with the ESCA technique it was possible to identify the chemical (bonding) state of elements contained in the atmospheric particulate matter collected on Nuclepore filters. Sulfur, nitrogen, mercury, chlorine, alkali, and alkaline earth metal species were identified in the Norfolk samples. ESCA binding energy data for aluminum indicated that three chemically different types of aluminum are present in the launch and background samples from NASA-KSC.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lecain, G.D.; Anna, L.O.; Fahy, M.F.
1998-08-01
Geothermal logging, air and core-water chemistry sampling, air-injection testing, and tracer testing were done in the northern Ghost Dance Fault at Yucca Mountain, Nevada, from November 1996 to August 1998. The study was done by the U.S. Geological Survey, in cooperation with the U.S. Department of Energy. The fault-testing drill room and test boreholes were located in the crystal-poor, middle nonlithophysal zone of the Topopah Spring Tuff, a tuff deposit of Miocene age. The drill room is located off the Yucca Mountain underground Exploratory Studies Facility at about 230 meters below ground surface. Borehole geothermal logging identified a temperature decreasemore » of 0.1 degree Celsius near the Ghost Dance Fault. The temperature decrease could indicate movement of cooler air or water, or both, down the fault, or it may be due to drilling-induced evaporative or adiabatic cooling. In-situ pneumatic pressure monitoring indicated that barometric pressure changes were transmitted from the ground surface to depth through the Ghost Dance Fault. Values of carbon dioxide and delta carbon-13 from gas samples indicated that air from the underground drill room had penetrated the tuff, supporting the concept of a well-developed fracture system. Uncorrected carbon-14-age estimates from gas samples ranged from 2,400 to 4,500 years. Tritium levels in borehole core water indicated that the fault may have been a conduit for the transport of water from the ground surface to depth during the last 100 years.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Steger, J.L.; Bursey, J.T.; Merrill, R.G.
1999-03-01
This report presents the results of laboratory studies to develop and evaluate a method for the sampling and analysis of phosgene from stationary sources of air emissions using diethylamine (DEA) in toluene as the collection media. The method extracts stack gas from emission sources and stabilizes the reactive gas for subsequent analysis. DEA was evaluated both in a benchtop study and in a laboratory train spiking study. This report includes results for both the benchtop study and the train spiking study. Benchtop studies to evaluate the suitability of DEA for collecting and analyzing phosgene investigated five variables: storage time, DEAmore » concentration, moisture/pH, phosgene concentration, and sample storage temperature. Prototype sampling train studies were performed to determine if the benchtop chemical studies were transferable to a Modified Method 5 sampling train collecting phosgene in the presence of clean air mixed with typical stack gas components. Four conditions, which varied the moisture and phosgene spike were evaluated in triplicate. In addition to research results, the report includes a detailed draft method for sampling and analysis of phosgene from stationary source emissions.« less
Briggiler Marcó, Mariángeles; Negro, Antonio Carlos; Alfano, Orlando Mario; Quiberoni, Andrea Del Luján
2017-04-12
The aims of this work were to design and build a photocatalytic reactor (UV-A/TiO 2 ) to study the inactivation of phages contained in bioaerosols, which constitute the main dissemination via phages in industrial environments. The reactor is a close system with recirculation that consists of a stainless steel camera (cubic form, side of 60 cm) in which air containing the phage particles circulates and an acrylic compartment with six borosilicate plates covered with TiO 2 . The reactor is externally illuminated by 20 UV-A lamps. Both compartments are connected by a fan to facilitate the sample circulation. Samples are injected into the camera using two piston nebulizers working in series whereas several methodologies for sampling (impinger/syringe, sampling on photocatalytic plates, and impact of air on slide) were assayed. The reactor setup was carried out using phage B1 (Lactobacillus plantarum), and assays demonstrated a decrease of phage counts of 2.7 log orders after 1 h of photocatalytic treatment. Photonic efficiencies of inactivation were assessed by phage sampling on the photocatalytic plates or by impact of air on a glass slide at the photocatalytic reactor exit. Efficiencies of the same order of magnitude were observed using both sampling methods. This study demonstrated that the designed photocatalytic reactor is effective to inactivate phage B1 (Lb. plantarum) contained in bioaerosols.
NASA Astrophysics Data System (ADS)
Handa, Daishi; Somada, Yuka; Ijyu, Moriaki; Azechi, Sotaro; Nakaema, Fumiya; Arakaki, Takemitsu; Tanahara, Akira
2010-05-01
The economic development and population growth in recent Asia spread air pollution. Emission rate of air pollutants from Asia, in particular oxides of nitrogen, surpassed those from North America and Europe and should continue to exceed them for decades. The study of the long-range transported air pollution from Asian continent has gained a special attention in Japan because of increase in photochemical oxidants in relatively remote islands. Okinawa Island is situated approximately 1500 km south of Tokyo, Japan, 2000 km southeast of Beijing, China, and 1000 km south of South Korea. Its location in Asia is well suited for studying long-range transport of air pollutants in East Asia because maritime air mass prevails during summer, while continental air mass dominates during fall, winter, and spring. The maritime air mass data can be seen as background and can be compared with continental air masses which have been affected by anthropogenic activities. Bulk aerosol samples were collected on quartz filters by using a high volume air sampler. Sampling duration was one week for each sample. We determined the concentrations of water-soluble anions, cations and dissolved organic carbon (DOC) in the bulk aerosols collected at the Cape Hedo Atmosphere and Aerosol Monitoring Station (CHAAMS) using ion chromatography, atomic absorption spectrometry, and total organic carbon analyzer, respectively. We will report water-soluble chemical components data of anions, cations and DOC in bulk atmospheric aerosols collected at CHAAMS during August, 2005 to April, 2010. Seasonal variation of water-soluble chemical components showed that the concentrations were relatively low in summer, higher in fall and winter, and the highest in spring. When air mass came from Asian Continent, the concentrations of water-soluble chemical components were much higher compared to the other directions. In addition, we calculated background concentration of water-soluble chemical components at Okinawa, Japan.
Tobin, John
1989-01-01
A sampling apparatus is provided which comprises a sampler for sampling air in the breathing zone of a wearer of the apparatus and a support for the sampler preferably in the form of a pair of eyeglasses. The sampler comprises a sampling assembly supported on the frame of the eyeglasses and including a pair of sample transport tubes which are suspended, in use, centrally of the frame so as to be disposed on opposite sides of the nose of the wearer and which each include an inlet therein that, in use, is disposed adjacent to a respective nostril of the nose of the wearer. A filter holder connected to sample transport tubes supports a removable filter for filtering out particulate material in the air sampled by the apparatus. The sample apparatus is connected to a pump for drawing air into the apparatus through the tube inlets so that the air passes through the filter.
Bashir, Wasim; McGovern, Frank; O'Brien, Phillip; Ryan, Margaret; Burke, Liam; Paull, Brett
2008-06-01
A major Irish study, based upon more than 8000 samples collected over the measurement period of 22 years, for sulfur dioxide (SO2-S), sulfate (SO4-S) and nitrogen dioxide (NO2-N) concentrations (microg m(-3)) within air, and the ionic composition of precipitation samples based on sodium (Na+), potassium (K+), magnesium (Mg2+), calcium (Ca2+), chloride (Cl-), sulfate (SO4-S), non-sea salt sulfate (nssSO4-S), ammonium (NH4-N), and nitrate (NO3-N) weighted mean concentrations (mg l(-1)), has been completed. For the air samples, the sulfur dioxide and sulfate concentrations decreased over the sampling period (1980-2004) by 75% and 45%, respectively, whereas no significant trend was observed for nitrogen dioxide. The highest concentrations for sulfur dioxide, sulfate and nitrogen dioxide were associated with wind originating from the easterly and northeasterly directions i.e. those influenced by Irish and European sources. The lowest concentrations were associated with the westerly directions i.e. for air masses originating in the North Atlantic region. This was further verified with the use of backward (back) trajectory analysis, which allowed tracing the movement of air parcels using the European Centre for Medium range Weather Forecasting (ECMWF) ERA-40 re-analysis data. High non-sea salt sulfate levels were being associated with air masses originating from Europe (easterlies) with lower levels from the Atlantic (westerlies). With the precipitation data, analysis of the non-sea salt sulfate concentrations showed a decrease by 47% since the measurements commenced.
Normand, Anne-Cécile; Ranque, Stéphane; Cassagne, Carole; Gaudart, Jean; Sallah, Kankoé; Charpin, Denis-André; Piarroux, Renaud
2016-03-01
Many ailments can be linked to exposure to indoor airborne fungus. However, obtaining a precise measurement of airborne fungal levels is complicated partly due to indoor air fluctuations and non-standardized techniques. Electrostatic dust collector (EDC) sampling devices have been used to measure a wide range of airborne analytes, including endotoxins, allergens, β-glucans, and microbial DNA in various indoor environments. In contrast, viable mold contamination has only been assessed in highly contaminated environments such as farms and archive buildings. This study aimed to assess the use of EDCs, compared with repeated air-impactor measurements, to assess airborne viable fungal flora in moderately contaminated indoor environments. Indoor airborne fungal flora was cultured from EDCs and daily air-impaction samples collected in an office building and a daycare center. The quantitative fungal measurements obtained using a single EDC significantly correlated with the cumulative measurement of nine daily air impactions. Both methods enabled the assessment of fungal exposure, although a few differences were observed between the detected fungal species and the relative quantity of each species. EDCs were also used over a 32-month period to monitor indoor airborne fungal flora in a hospital office building, which enabled us to assess the impact of outdoor events (e.g. ground excavations) on the fungal flora levels on the indoor environment. In conclusion, EDC-based measurements provided a relatively accurate profile of the viable airborne flora present during a sampling period. In particular, EDCs provided a more representative assessment of fungal levels compared with single air-impactor sampling. The EDC technique is also simpler than performing repetitive air-impaction measures over the course of several consecutive days. EDC is a versatile tool for collecting airborne samples and was efficient for measuring mold levels in indoor environments. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
Cetin, Banu; Ozturk, Fatma; Keles, Melek; Yurdakul, Sema
2017-01-01
Istanbul, one of the mega cities in the world located between Asia and Europe, has suffered from severe air pollution problems due to rapid population growth, traffic and industry. Atmospheric levels of PAHs and PCBs were investigated in Istanbul at 22 sampling sites during four different sampling periods using PUF disk passive air samplers and spatial and temporal variations of these chemicals were determined. Soil samples were also taken at the air sampling sites. At all sites, the average ambient air Σ 15 PAH and Σ 41 PCB concentrations were found as 85.6 ± 68.3 ng m -3 and 246 ± 122 pg m -3 , respectively. Phenanthrene and anthracene were the predominant PAHs and low molecular weight congeners dominated the PCBs. The PAH concentrations were higher especially at urban sites close to highways. However, the PCBs showed moderately uniform spatial variations. Except four sites, the PAH concentrations were increased with decreasing temperatures during the sampling period, indicating the contributions of combustion sources for residential heating, while PCB concentrations were mostly increased with the temperature, probably due to enhanced volatilization at higher temperatures from their sources. The results of the Factor Analysis represented the impact of traffic, petroleum, coal/biomass and natural gas combustion and medical waste incineration plants on ambient air concentrations. A similar spatial distribution trend was observed in the soil samples. Fugacity ratio results indicated that the source/sink tendency of soil for PAHs and PCBs depends on their volatility and temperature; soil generally acts as a source for lighter PAHs and PCBs particularly in higher temperatures while atmospheric deposition is a main source for higher molecular weight compounds in local soils. Toxicological effect studies also revealed the severity of air and soil pollution especially in terms of PAHs in Istanbul. Copyright © 2016 Elsevier Ltd. All rights reserved.
Density assessment and mapping of microorganisms around a biocomposting plant in Sanandaj, Iran.
Rashidi, Sanaz; Shahmoradi, B; Maleki, Afshin; Sharafi, Kiomars; Darvishi, Ebrahim
2017-05-01
Exposure to microorganisms can cause various diseases or exacerbate the excitatory responses, inflammation, dry cough and shortness of breath, reduced lung function, chronic obstructive pulmonary disease, and allergic response or allergic immune. The aim of the present study was to investigate the density of microorganisms around the air of processing facilities of a biocomposting plant. Each experiment was carried out according to ASTM E884-82 (2001) method. The samples were collected from inhaled air in four locations of the plant, which had a high traffic of workers and employees, including screen, conveyor belt, aerated compost pile, and static compost pile. The sampling was repeated five times for each location selected. The wind speed and its direction were measured using an anemometer. Temperature and humidity were also recorded at the time of sampling. The multistage impactor used for sampling was equipped with a solidified medium (agar) and a pump (with a flow rate of 28.3 l/m) for passing air through the media. It was found that the mean density of total bacteria was >1.7 × 10 3 cfu/m 3 in the study area. Moreover, the mean densities of fungi, intestinal bacteria (Klebsiella), and Staphylococcus aureus were 5.9 × 10 3 , 3.3 × 10 3 , and 4.1 × 10 3 cfu/m 3 , respectively. In conclusion, according to the findings, the density of bacteria and fungi per cubic meter of air in the samples collected around the processing facilities of the biocomposting plant in Sanandaj City was higher than the microbial standard for inhaled air.
Combined PIXE and X-ray SEM studies on time-resolved deposits of welding shop aerosols
NASA Astrophysics Data System (ADS)
Barfoot, K. M.; Mitchell, I. V.; Verheyen, F.; Babeliowsky, T.
1981-03-01
Time-resolved deposits of welding shop air particulates have been obtained using a streak sampling system. PIXE analysis of these deposits, using 2 MeV protons, typically revealed the presence of a large number of elements, with many in the range Z = 11-30. Strong variations, up to three orders of magnitude, in the concentrations of several elements such as Al, Si and Fe as well as Zn, Na, K and Ca were found. The 2 h sampling resolution normally used was found to be insufficient to follow the short pollution episodes that regularly occur in a welding shop environment and so sampling with a 20 min resolution was used. The variation of elemental concentrations for different sampling times together with information on the physical nature of these air particulates, determined with a scanning electron microscope (SEM) and Si(Li) X-ray detector attachment, are presented. This type of information together with that obtained from the PIXE analysis is of importance in industrial hygiene studies. The need to make corrections for partial filter clogging, based on air-flow rate monitoring, is discussed.
Rosenberger, Wolfgang; Beckmann, Bibiana; Wrbitzky, Renate
2016-04-15
This paper presents the strategy and results of in-flight measurements of airborne aldehydes during normal operation and reported "smell events" on commercial aircraft. The aldehyde-measurement is a part of a large-scale study on cabin-air quality. The aims of this study were to describe cabin-air quality in general and to detect chemical abnormalities during the so-called "smell-events". Adsorption and derivatization of airborne aldehydes on 2,4-dinitrophenylhydrazine coated silica gel (DNPH-cartridge) was applied using tailor-made sampling kits. Samples were collected with battery supplied personal air sampling pumps during different flight phases. Furthermore, the influence of ozone was investigated by simultaneous sampling with and without ozone absorption unit (ozone converter) assembled to the DNPH-cartridges and found to be negligible. The method was validated for 14 aldehydes and found to be precise (RSD, 5.5-10.6%) and accurate (recovery, 98-103 %), with LOD levels being 0.3-0.6 μg/m(3). According to occupational exposure limits (OEL) or indoor air guidelines no unusual or noticeable aldehyde pollution was observed. In total, 353 aldehyde samples were taken from two types of aircraft. Formaldehyde (overall average 5.7 μg/m(3), overall median 4.9 μg/m(3), range 0.4-44 μg/m(3)), acetaldehyde (overall average 6.5 μg/m(3), overall median 4.6, range 0.3-90 μg/m(3)) and mostly very low concentrations of other aldehydes were measured on 108 flights. Simultaneous adsorption and derivatization of airborne aldehydes on DNPH-cartridges to the Schiff bases and their HPLC analysis with UV absorbance detection is a useful method to measure aldehydes in cabin-air of commercial aircraft. Copyright © 2015 Elsevier B.V. All rights reserved.
Indoor air quality in Latino homes in Boulder, Colorado
NASA Astrophysics Data System (ADS)
Escobedo, Luis E.; Champion, Wyatt M.; Li, Ning; Montoya, Lupita D.
2014-08-01
Indoor concentrations of airborne pollutants can be several times higher than those found outdoors, often due to poor ventilation, overcrowding, and the contribution of indoor sources within a home. Americans spend most of their time indoors where exposure to poor indoor air quality (IAQ) can result in diminished respiratory and cardiovascular health. This study measured the indoor air quality in 30 homes of a low-income Latino community in Boulder, Colorado during the summer of 2012. Participants were administered a survey, which included questions on their health conditions and indoor air pollution sources like cigarette smoke, heating fuel, and building materials. Twenty-four hour samples of fine particulate matter (PM2.5) from the indoor air were collected in each home; ambient PM2.5 samples were collected each day as well. Concurrent air samples were collected onto 47 mm Teflo and Tissuquartz filter at each location. Teflo filters were analyzed gravimetrically to measure PM2.5 and their extracts were used to determine levels of proteins and endotoxins in the fine fraction. The Tissuquartz filters were analyzed for elemental and organic carbon content (EC/OC). Results indicated that the indoor air contained higher concentrations of PM2.5 than the ambient air, and that the levels of OC were much higher than EC in both indoor and outdoor samples. This community showed no smoking in their homes and kept furry pets indoors at very low rates; therefore, cooking is likely the primary source of indoor PM. For responders with significant exposure to PM, it appeared to be primarily from occupational environments or childhood exposure abroad. Our findings indicate that for immigrant communities such as this, it is important to consider not only their housing conditions but also the relevant prior exposures when conducting health assessments.
Sequential air sampler system : its use by the Virginia Department of Highways & Transportation.
DOT National Transportation Integrated Search
1975-01-01
The Department of Highways & Transportation needs an economical and efficient air quality sampling system for meeting requirements on air monitoring for proposed projects located In critical areas. Two sequential air sampling systems, the ERAI and th...
Yadav, Ishwar Chandra; Devi, Ningombam Linthoingambi; Li, Jun; Zhang, Gan; Breivik, Knut
2017-01-01
Ambient air is a core media chosen for monitoring under the Stockholm Convention on POPs. While extensive monitoring of POPs in ambient air has been carried out in some parts of the globe, there are still regions with very limited information available, such as some developing countries as Nepal. This study therefore aims to target the occurrence of selected POPs in Nepal in suspected source areas/more densely populated regions. Four potential source regions in Nepal were furthermore targeted as it was hypothesized that urban areas at lower altitudes (Birgunj and Biratnagar located at approximately 86 and 80 m.a.s.l.) would be potentially more affected by OCPs because of more intensive agricultural activities in comparison to urban areas at higher altitudes (Kathmandu, Pokhara located 1400 and 1135 m.a.s.l). As some of these areas could also be impacted by LRAT, air mass back trajectories during the sampling period were additionally evaluated using HYSPLIT. The concentrations of overall POPs were twice as high in plain areas in comparison to hilly areas. DDTs and HCHs were most frequently detected in the air samples. The high p,p'-DDT/(pp'-DDE + pp'-DDD) ratio as well as the low o,p'-DDT/p,p'-DDT ratio observed in this study was inferred as continuing use of technical DDT. High levels of ∑ 26 PCBs were linked to proximity to highly urbanized and industrial areas, indicating the potential source of PCBs. The measured concentrations of legacy POPs in air from this study is assumed to represent a negligible health risk through inhalation of ambient air, however, other modes of human exposure could still be relevant in Nepal. The air mass backward trajectory analysis revealed that most of the air masses sampled originated from India and the Bay of Bengal. Copyright © 2016 Elsevier Ltd. All rights reserved.
Rizzetto, R; Mansi, A; Panatto, D; Rizzitelli, E; Tinteri, C; Sasso, T; Gasparini, R; Crovari, P
2008-03-01
Air pollution in confined environments is a serious health problem, in that most people spend long periods indoors (in homes, offices, classrooms etc.). Some people (children, the elderly, heart disease patients, asthmatic or allergic subjects) are at greater risk because of their conditions of frailty. The growing use of air-conditioning systems in many public and private buildings aggravates this health risk, especially when these systems are not correctly installed or regularly serviced. The aim of our study was to verify the capacity of Ag+ ions to stop the growth of bacteria and moulds inside the ducts of Heating, Ventilation and Air Conditioning system ducts (HVAC) systems when these ducts were lined with active Ag+ ions zeolite-coated panels. A Y-shaped HVAC model with two branches was used; one branch was made of traditional galvanized iron, as was the whole system, while the other was lined with active Ag+ zeolite-coated polyurethane panels. During the test, samples of dust present inside both ducts were collected and seeded in liquid and solid media to detect bacteria and moulds. The presence of bacteria was also sought in the air emerging from the outlets of both ducts. Tests made on samples of particulate collected from the two different ducts revealed a lower total bacterial load in the samples collected from the Ag+ zeolite-coated duct than in the samples from the traditional Zn galvanized duct. In addition, the values of bacterial load found in the air emerging from the Ag+ ions zeolite-lined duct were 5 times lower than those found in the air from the traditional galvanized iron duct. The utilization of Ag+ zeolite-coated panels in air-conditioning systems could improve the quality of the emerging air in comparison with traditional installations in galvanized iron. This innovation could prove particularly advantageous in the event of accidents during the installation of air-conditioning systems or of contaminated aerosols coming from outside.
The purpose of this SOP is to describe the acid digestion of soil, house dust, air filter, and surface or dermal wipe samples for analysis using inductively coupled plasma atomic emissions spectrometry (ICP-AES) and/or graphite furnace atomic absorption spectrometry (GFAAS) or fl...
2010-03-16
Exceeded at ERP Soil and Groundwater Sites 86 A-2a. Identification of IRIS Chemicals of Interest on the ATSDR CERCLA Priority List of Hazardous...the Number (Bold Font) of Air Force ERP Samples in Which They Were Detected 317 A-4d. Air Force ERP Soil Samples: IRIS Chemicals of Interest...Ranked by the Number (Bold Font) of Air Force ERP Soil Samples in Which They Were Detected 333 A-4e. Air Force ERP Groundwater Samples: IRIS Chemicals of
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tyndall, R.L.
1983-07-01
Air was sampled at the point of discharge and at short distances downwind and upwind from industrial and power-plant cooling towers. Both high-volume electrostatic and impinger type samplers were used. Concentrates of the air samples were analyzed for Legionnaires' Disease Bacteria (LDB). In some cases, the samples were also tested for the presence of free-living amoebae. The concentrations of LDB in the air samples were well below the minimal infectious dose for guinea pigs and precluded testing of the samples for infectious LDB. Results of LDB analysis were related to the meteorological conditions at the time of sampling. Generally, themore » concentrations of LDB in the air at the discharge of the cooling towers were 1 x 10/sup -6/ to 1 x 10/sup -7/ of that found in comparable volumes of tower basin water. During periods of high humidity and wind speed, LDB was detected in a few downwind samples and one upwind sample. One site with extensive construction and excavation activity had higher LDB concentrations in air samples relative to other sites. Nonpathogenic Naegleria were present in one of two air samples taken in the mist at the base of a natural-draft cooling tower.« less
NASA Astrophysics Data System (ADS)
Zhou, Guoliang; Su, Lin; Cheng, Qia; Wu, Longbing
2017-08-01
Microchannel evaporator has been widely applied in automobile air conditioning, while it faces the problem of refrigerant maldistribution which deteriorates the thermal performance of evaporator. In this study, the performances of microchannel evaporators with different port structures are experimentally investigated for purpose of reducing evaporator pressure drop. Four evaporator samples with different port number and hydraulic diameter are made for this study. The performances of the evaporator samples are tested on a psychometric calorimeter test bench with the refrigerant R-134A at a real automobile air conditioning. The results on the variations of the evaporator pressure drop and evaporator surface temperature distribution are presented and analyzed. By studying the performance of an evaporator, seeking proper port structure is an approach to reduce refrigerant pressure drop as well as improve refrigerant distribution.
Effect of temperature on the breakthrough of a charcoal tube during vinyl chloride monomer sampling.
Roh, J; Park, Y J; Kim, C N; Lim, N G; Lee, S H; Song, J S; Won, J U; Talaska, G
2000-01-01
This study evaluated the effects of temperature on breakthrough of two standard collection media at various concentrations during vinyl chloride monomer (VCM) sampling. The National Institute for Occupational Safety and Health (NIOSH) and Occupational Safety and Health Administration (OSHA) methods were evaluated. To determine whether breakthrough of VCM would occur at the extremes of exposure and temperature that might be encountered in some workplaces, air samples containing 4 ppm (10.24 mg/m3), 8 ppm (20.45 mg/m3), 16 ppm (40.98 mg/m3), and 32 ppm (81.80 mg/m3) of VCM were collected at temperatures of 4, 22, and 40 degrees C. Five liters of air was sampled at the rate of 0.05 L/min for 100 min using the activated charcoal tube recommended by NIOSH. A second tube was added to the sampling train to collect any VCM that might not have been absorbed in the first tube. To collect VCM air samples by the OSHA method, two carbon molecular sieve tubes were connected serially and 3 L of air was sampled at the rate of 0.05 L/min for 60 min. A gas chromatograph with a flame ionization detector and ultra 2 capillary column was used to analyze VCM. Significant breakthrough was found when sampling at higher temperatures with the NIOSH method. No breakthrough was found when samples were collected using the OSHA media at different temperatures and concentrations. Therefore, under hot ambient conditions (>22 degrees C), the possibility of breakthrough should be considered when sampling VCM by the NIOSH method.
Johnston, James D.; Tuttle, Steven C.; Nelson, Morgan C.; Bradshaw, Rebecca K.; Hoybjerg, Taylor G.; Johnson, Julene B.; Kruman, Bryce A.; Orton, Taylor S.; Cook, Ryan B.; Eggett, Dennis L.; Weber, K. Scott
2016-01-01
Concerns about energy consumption and climate change make residential evaporative coolers a popular alternative to central air conditioning in arid and semi-arid climates. However, evaporative coolers have been shown to significantly increase indoor relative humidity and dust mite allergen levels in some studies, while showing no association in other studies. Improved measurement of temporal fluctuations in indoor relative humidity may help identify factors that promote mite growth in homes in dry climates. Dust samples and continuous indoor relative humidity measurements were collected from homes with central air conditioning and homes with evaporative coolers in Utah. Samples were collected over two seasons, winter/spring (Jan–Apr) and summer (July–Sept), 2014. Dust samples were analyzed for Der p 1 and Der f 1 using a two-site monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) analysis. Housing characteristics including age of home, occupant density, and age of mattresses, furniture, and carpeting were also measured. Positive Der p 1 or Der f 1 samples were found in 25.0% of the homes and there was no difference in mean allergen levels by type of air conditioning. Indoor relative humidity was significantly higher in homes with evaporative coolers compared to those with central air conditioning during the summer. Homes with evaporative coolers also spent significantly more time during summer above 55.0% and 65.0% relative humidity compared to central air homes, but not above 75.0%. Findings from this study suggest that increased humidity from evaporative coolers may not be sufficient to exceed the critical equilibrium humidity or maintain humidity excursions for sufficient duration in relatively larger single-family homes in semi-arid climates to support mite growth and reproduction. PMID:26808528
Johnston, James D; Tuttle, Steven C; Nelson, Morgan C; Bradshaw, Rebecca K; Hoybjerg, Taylor G; Johnson, Julene B; Kruman, Bryce A; Orton, Taylor S; Cook, Ryan B; Eggett, Dennis L; Weber, K Scott
2016-01-01
Concerns about energy consumption and climate change make residential evaporative coolers a popular alternative to central air conditioning in arid and semi-arid climates. However, evaporative coolers have been shown to significantly increase indoor relative humidity and dust mite allergen levels in some studies, while showing no association in other studies. Improved measurement of temporal fluctuations in indoor relative humidity may help identify factors that promote mite growth in homes in dry climates. Dust samples and continuous indoor relative humidity measurements were collected from homes with central air conditioning and homes with evaporative coolers in Utah. Samples were collected over two seasons, winter/spring (Jan-Apr) and summer (July-Sept), 2014. Dust samples were analyzed for Der p 1 and Der f 1 using a two-site monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) analysis. Housing characteristics including age of home, occupant density, and age of mattresses, furniture, and carpeting were also measured. Positive Der p 1 or Der f 1 samples were found in 25.0% of the homes and there was no difference in mean allergen levels by type of air conditioning. Indoor relative humidity was significantly higher in homes with evaporative coolers compared to those with central air conditioning during the summer. Homes with evaporative coolers also spent significantly more time during summer above 55.0% and 65.0% relative humidity compared to central air homes, but not above 75.0%. Findings from this study suggest that increased humidity from evaporative coolers may not be sufficient to exceed the critical equilibrium humidity or maintain humidity excursions for sufficient duration in relatively larger single-family homes in semi-arid climates to support mite growth and reproduction.
Detection of the urban release of a bacillus anthracis simulant by air sampling.
Garza, Alexander G; Van Cuyk, Sheila M; Brown, Michael J; Omberg, Kristin M
2014-01-01
In 2005 and 2009, the Pentagon Force Protection Agency (PFPA) staged deliberate releases of a commercially available organic pesticide containing Bacillus amyloliquefaciens to evaluate PFPA's biothreat response protocols. In concert with, but independent of, these releases, the Department of Homeland Security sponsored experiments to evaluate the efficacy of commonly employed air and surface sampling techniques for detection of an aerosolized biological agent. High-volume air samplers were placed in the expected downwind plume, and samples were collected before, during, and after the releases. Environmental surface and personal air samples were collected in the vicinity of the high-volume air samplers hours after the plume had dispersed. The results indicate it is feasible to detect the release of a biological agent in an urban area both during and after the release of a biological agent using high-volume air and environmental sampling techniques.
NHEXAS PHASE I MARYLAND STUDY--QA ANALYTICAL RESULTS FOR PESTICIDES IN REPLICATE SAMPLES
The Pesticides in Replicates data set contains the analytical results of measurements of up to 10 pesticides in 68 replicate (duplicate) samples from 41 households. Measurements were made in samples of indoor air, dust, soil, drinking water, food, and beverages. Duplicate sampl...
Pesticides in the atmosphere of the Mississippi River Valley, part II - Air
Foreman, W.T.; Majewski, M.S.; Goolsby, D.A.; Wiebe, F.W.; Coupe, R.H.
2000-01-01
Weekly composite air samples were collected from early April through to mid-September 1995 at three paired urban and agricultural sites along the Mississippi River region of the Midwestern United States. The paired sampling sites were located in Mississippi, Iowa, and Minnesota. A background site, removed from dense urban and agricultural areas, was located on the shore of Lake Superior in Michigan. Each sample was analyzed for 49 compounds; of these, 21 of 26 herbicides, 13 of 19 insecticides, and 4 of 4 related transformation products were detected during the study, with most pesticides detected in more than one sample. The maximum number of pesticides detected in an air sample was 18. Herbicides were the predominant type of pesticide detected at every site. Detection frequencies of most herbicides were similar at the urban and agricultural sites in Iowa and Minnesota. In Mississippi, herbicides generally were detected more frequently at the agricultural site. The insecticides chlorpyrifos, diazinon, and carbaryl, which are used in agricultural and non-agricultural settings, were detected more frequently in urban sites than agricultural sites in Mississippi and Iowa. Methyl parathion was detected in 70% of the samples from the Mississippi agricultural site and at the highest concentration (62 ng/m3 air) of any insecticide measured in the study. At the background site, dacthal (100%), atrazine (35%), cyanazine (22%), and the (primarily atrazine) triazine transformation products CIAT (35%) and CEAT (17%) were detected most frequently, suggesting their potential for long-range atmospheric transport. Copyright (C) 2000 Elsevier Science B.V.
Mapping Air Quality Index of Carbon Monoxide (CO) in Medan City
NASA Astrophysics Data System (ADS)
Suryati, I.; Khair, H.
2017-03-01
This study aims to map and analyze air quality index of carbon monoxide (CO) in Medan City. This research used 12 (twelve) sampling points around in Medan with an hour duration each point. CO concentration was analyzed using the NDIR CO Analyzer sampling tool. The concentration CO was obtained between 1 ppm - 23 ppm, with an average concentration was 9.5 ppm. This condition is still below the national ambient air quality standard set by Government Regulation of Indonesian Republic Number 41-1999 amounted to 29 ppm. The result of CO concentration measurements was converted into air pollutant standard index, obtained the index value of 58 - 204. Surfer 10 was used to create map of air pollutant standard index for CO. The map illustrates very unhealthy area where located in the Medan Belawan district. The main factors affecting the concentration of CO are from transportation and meteorological factors.
Cho, David R; Cho, Kyung J; Hawkins, Irvin F
2006-01-01
To assess air contamination in the hand-held syringes currently used for CO2 delivery and to determine whether there is an association between their position and the rate of air contamination. Assessment of air contamination in the syringe (20 ml) included theoretical modeling, mathematical calculation, and gas chromatography (GC). The model was used with Fick's first law to calculate the diffusion of CO2 and the amount of air contamination. For GC studies, the syringes were placed in the upright, horizontal, and inverted positions and gas samples were obtained after 5, 10, 20, 30, and 60 min. All trials with each position for each sampling time were performed five times. The amounts of air contamination with time calculated mathematically were 5-10% less than those of GC. With the diffusivity of air-CO2 at 0.1599 cm2/sec (9.594 cm2/min), air contamination was calculated to be 60% at 60 min. With GC air contamination was 13% at 5 min, 31% at 20 min, 43% at 30 min, and 68% at 60 min. There was no difference in air contamination between the different syringe positions. Air contamination occurs in hand-held syringes filled with CO2 when they are open to the ambient air. The amounts of air contamination over time are similar among syringes placed in the upright, horizontal, and inverted positions.
A large-scale ambient monitoring program vas conducted in Boise, Idaho, during the 1986-1987 winter heating season to evaluate the impact of residential wood combustion (RWC) and automotive emissions on the local air shed. onsecutive 12-h particle, organic, and gaseous samples we...
The first survey of airborne trace elements at airport using moss bag technique.
Vuković, Gordana; Urošević, Mira Aničić; Škrivanj, Sandra; Vergel, Konstantin; Tomašević, Milica; Popović, Aleksandar
2017-06-01
Air traffic represents an important way of social mobility in the world, and many ongoing discussions are related to the impacts that air transportation has on local air quality. In this study, moss Sphagnum girgensohnii was used for the first time in the assessment of trace element content at the international airport. The moss bags were exposed during the summer of 2013 at four sampling sites at the airport 'Nikola Tesla' (Belgrade, Serbia): runway (two), auxiliary runway and parking lot. According to the relative accumulation factor (RAF) and the limit of quantification of the moss bag technique (LOQ T ), the most abundant elements in the samples were Zn, Na, Cr, V, Cu and Fe. A comparison between the element concentrations at the airport and the corresponding values in different land use classes (urban central, suburban, industrial and green zones) across the city of Belgrade did not point out that the air traffic and associated activities significantly contribute to the trace element air pollution. This study emphasised an easy operational and robust (bio)monitoring, using moss bags as a suitable method for assessment of air quality within various microenvironments with restriction in positioning referent instrumental devices.
Does the air condition system in busses spread allergic fungi into driver space?
Sowiak, Małgorzata; Kozajda, Anna; Jeżak, Karolina; Szadkowska-Stańczyk, Irena
2018-02-01
The aim of this study was to establish whether the air-conditioning system in buses constitutes an additional source of indoor air contamination with fungi, and whether or not the fungi concentration depends on the period from the last disinfection of the system, combined with replacement of the cabin dust particle filter. The air samples to fungi analysis using impact method were taken in 30 buses (20 with an air-conditioning system, ACS; 10 with a ventilation system, VS) in two series: 1 and 22 weeks after cabin filter replacement and disinfection of the air-conditioning system. During one test in each bus were taken two samples: before the air-conditioning or ventilation system switched on and 6 min after operating of these systems. The atmospheric air was the external background (EB). After 1 week of use of the system, the fungi concentrations before starting of the ACS and VS system were 527.8 and 1053.0 cfu/m 3 , respectively, and after 22 weeks the concentrations were 351.9 and 1069.6 cfu/m 3 , respectively. While in the sample after 6 min of ACS and VS system operating, the fungi concentration after 1 week of use was 127.6 and 233.7 cfu/m 3 , respectively, and after 22 weeks it was 113.3 and 324.9 cfu/m 3 , respectively. Results do not provide strong evidence that air-conditioning system is an additional source of indoor air contamination with fungi. A longer operation of the system promoted increase of fungi concentration in air-conditioned buses only.
Nuckols, John R; Ashley, David L; Lyu, Christopher; Gordon, Sydney M; Hinckley, Alison F; Singer, Philip
2005-07-01
Individual exposure to trihalomethanes (THMs) in tap water can occur through ingestion, inhalation, or dermal exposure. Studies indicate that activities associated with inhaled or dermal exposure routes result in a greater increase in blood THM concentration than does ingestion. We measured blood and exhaled air concentrations of THM as biomarkers of exposure to participants conducting 14 common household water use activities, including ingestion of hot and cold tap water beverages, showering, clothes washing, hand washing, bathing, dish washing, and indirect shower exposure. We conducted our study at a single residence in each of two water utility service areas, one with relatively high and the other low total THM in the residence tap water. To maintain a consistent exposure environment for seven participants, we controlled water use activities, exposure time, air exchange, water flow and temperature, and nonstudy THM sources to the indoor air. We collected reference samples for water supply and air (pre-water use activity), as well as tap water and ambient air samples. We collected blood samples before and after each activity and exhaled breath samples at baseline and post-activity. All hot water use activities yielded a 2-fold increase in blood or breath THM concentrations for at least one individual. The greatest observed increase in blood and exhaled breath THM concentration in any participant was due to showering (direct and indirect), bathing, and hand dishwashing. Average increase in blood THM concentration ranged from 57 to 358 pg/mL due to these activities. More research is needed to determine whether acute and frequent exposures to THM at these concentrations have public health implications. Further research is also needed in designing epidemiologic studies that minimize data collection burden yet maximize accuracy in classification of dermal and inhalation THM exposure during hot water use activities.
Nuckols, John R.; Ashley, David L.; Lyu, Christopher; Gordon, Sydney M.; Hinckley, Alison F.; Singer, Philip
2005-01-01
Individual exposure to trihalomethanes (THMs) in tap water can occur through ingestion, inhalation, or dermal exposure. Studies indicate that activities associated with inhaled or dermal exposure routes result in a greater increase in blood THM concentration than does ingestion. We measured blood and exhaled air concentrations of THM as biomarkers of exposure to participants conducting 14 common household water use activities, including ingestion of hot and cold tap water beverages, showering, clothes washing, hand washing, bathing, dish washing, and indirect shower exposure. We conducted our study at a single residence in each of two water utility service areas, one with relatively high and the other low total THM in the residence tap water. To maintain a consistent exposure environment for seven participants, we controlled water use activities, exposure time, air exchange, water flow and temperature, and nonstudy THM sources to the indoor air. We collected reference samples for water supply and air (pre–water use activity), as well as tap water and ambient air samples. We collected blood samples before and after each activity and exhaled breath samples at baseline and postactivity. All hot water use activities yielded a 2-fold increase in blood or breath THM concentrations for at least one individual. The greatest observed increase in blood and exhaled breath THM concentration in any participant was due to showering (direct and indirect), bathing, and hand dishwashing. Average increase in blood THM concentration ranged from 57 to 358 pg/mL due to these activities. More research is needed to determine whether acute and frequent exposures to THM at these concentrations have public health implications. Further research is also needed in designing epidemiologic studies that minimize data collection burden yet maximize accuracy in classification of dermal and inhalation THM exposure during hot water use activities. PMID:16002374
Yang, Chao-Tung; Liao, Chi-Jui; Liu, Jung-Chun; Den, Walter; Chou, Ying-Chyi; Tsai, Jaw-Ji
2014-02-01
Indoor air quality monitoring in healthcare environment has become a critical part of hospital management and policy. Manual air sampling and analysis are cost-inhibitive and do not provide real-time air quality data and response measures. In this month-long study over 14 sampling locations in a public hospital in Taiwan, we observed a positive correlation between CO(2) concentration and population, total bacteria, and particulate matter concentrations, thus monitoring CO(2) concentration as a general indicator for air quality could be a viable option. Consequently, an intelligent environmental monitoring system consisting of a CO(2)/temperature/humidity sensor, a digital plug, and a ZigBee Router and Coordinator was developed and tested. The system also included a backend server that received and analyzed data, as well as activating ventilation and air purifiers when CO(2) concentration exceeded a pre-set value. Alert messages can also be delivered to offsite users through mobile devices.
Viegas, Susana; Caetano, Liliana Aranha; Korkalainen, Merja; Faria, Tiago; Pacífico, Cátia; Carolino, Elisabete; Quintal Gomes, Anita; Viegas, Carla
2017-01-01
Organic dust and related microbial exposures are the main inducers of several respiratory symptoms. Occupational exposure to organic dust is very common and has been reported in diverse settings. In vitro tests using relevant cell cultures can be very useful for characterizing the toxicity of complex mixtures present in the air of occupational environments such as organic dust. In this study, the cell viability and the inflammatory response, as measured by the production of pro-inflammatory cytokines tumor necrosis factor-α (TNFα) and interleukin-1 β (IL-1β), were determined in human macrophages derived from THP-1 monocytic cells. These cells were exposed to air samples from five occupational settings known to possess high levels of contamination of organic dust: poultry and swine feed industries, waste sorting, poultry production and slaughterhouses. Additionally, fungi and particle contamination of those settings was studied to better characterize the organic dust composition. All air samples collected from the assessed workplaces caused both cytotoxic and pro-inflammatory effects. The highest responses were observed in the feed industry, particularly in swine feed production. This study emphasizes the importance of measuring the organic dust/mixture effects in occupational settings and suggests that differences in the organic dust content may result in differences in health effects for exposed workers. PMID:29051440
NASA Astrophysics Data System (ADS)
Yohana, Eflita; Yulianto, Mohamad Endy; Kwang-Hwang, Choi; Putro, Bondantio; Yohanes Aditya W., A.
2015-12-01
The study of humidity distribution simulation inside a room has been widely conducted by using computational fluid dynamics (CFD). Here, the simulation was done by employing inputs in the experiment of air humidity reduction in a sample house. Liquid dessicant CaCl2was used in this study to absorb humidity in the air, so that the enormity of humidity reduction occured during the experiment could be obtained.The experiment was conducted in the morning at 8 with liquid desiccant concentration of 50%, nozzle dimension of 0.2 mms attached in dehumidifier, and the debit of air which entered the sample house was 2.35 m3/min. Both in inlet and outlet sides of the room, a DHT 11 censor was installed and used to note changes in humidity and temperature during the experiment. In normal condition without turning on the dehumidifier, the censor noted that the average temperature inside the room was 28°C and RH of 65%.The experiment result showed that the relative humidity inside a sample house was decreasing up to 52% in inlet position. Further, through the results obtained from CFD simulation, the temperature distribution and relative humidity inside the sample house could be seen. It showed that the concentration of liquid desiccant of 50% experienced a decrease while the relative humidity distribution was considerably good since the average RH was 55% followed by the increase in air temperature of 29.2° C inside the sample house.
Wang, I-Ting Ivy; Cheng, Shu-Fang; Tsai, Shih-Wei
2014-02-21
Synthetic musk is widely used in various scented consumer products. However, the exposure via inhalation is often ignored due to pleasant smells. In addition, the information regarding the distribution of synthetic musk in air is limited. Hence, this research is aimed to develop a highly sensitive and widely applicable method for the determination of airborne synthetic musk. In this study, polyurethane foam (PUF) and filter were employed for active air sampling. Microwave assisted extraction (MAE) and nitrogen evaporator were performed for sample preparation. A gas chromatography coupled with triple quadrupole tandem mass spectrometer (GC/MS-MS) with specific multiple reaction monitoring (MRM) transition pairs was applied for sample analysis. Compared with using selected ion monitoring (SIM) mode traditionally, the sensitivities were improved in this study about an order at least. In terms of air concentration, as low as 0.48ngm(-3) can be determined when sampling at 3.5Lmin(-1) for 8h. The method established was further applied to the analysis of synthetic musk compounds in air samples collected in a cosmetics plant. The results showed that the airborne concentrations of gaseous polycyclic musk, gaseous nitro-musk, and particle-phase polycyclic musk were 6.4×10(2), 4.0×10(1) and 3.1×10(2)ngm(-3), respectively. Meanwhile, Cashmeran, Celstolide, Galaxolide, and Tonalide were found as the dominant musk compounds in the factory investigated. Copyright © 2014 Elsevier B.V. All rights reserved.
How smoke-free laws improve air quality: A global study of Irish pubs
Carpenter, Carrie M.; Travers, Mark J.; Cummings, K. Michael; Hyland, Andrew; Mulcahy, Maurice; Clancy, Luke
2009-01-01
Introduction The present study examined indoor air quality in a global sample of smoke-free and smoking-permitted Irish pubs. We hypothesized that levels of respirable suspended particles, an important marker of secondhand smoke, would be significantly lower in smoke-free Irish pubs than in pubs that allowed smoking. Methods Indoor air quality was assessed in 128 Irish pubs in 15 countries between 21 January 2004 and 10 March 2006. Air quality was evaluated using an aerosol monitor, which measures the level of fine particle (PM2.5) pollution in the air. A standard measurement protocol was used by data collectors across study sites. Results Overall, the level of air pollution inside smoke-free Irish pubs was 93% lower than the level found in pubs where smoking was permitted. Discussion Levels of indoor air pollution can be massively reduced by enacting and enforcing smoke-free policies. PMID:19380381
How smoke-free laws improve air quality: a global study of Irish pubs.
Connolly, Gregory N; Carpenter, Carrie M; Travers, Mark J; Cummings, K Michael; Hyland, Andrew; Mulcahy, Maurice; Clancy, Luke
2009-06-01
The present study examined indoor air quality in a global sample of smoke-free and smoking-permitted Irish pubs. We hypothesized that levels of respirable suspended particles, an important marker of secondhand smoke, would be significantly lower in smoke-free Irish pubs than in pubs that allowed smoking. Indoor air quality was assessed in 128 Irish pubs in 15 countries between 21 January 2004 and 10 March 2006. Air quality was evaluated using an aerosol monitor, which measures the level of fine particle (PM(2.5)) pollution in the air. A standard measurement protocol was used by data collectors across study sites. Overall, the level of air pollution inside smoke-free Irish pubs was 93% lower than the level found in pubs where smoking was permitted. Levels of indoor air pollution can be massively reduced by enacting and enforcing smoke-free policies.
[Microbial air monitoring in operating theatre: active and passive samplings].
Pasquarella, C; Masia, M D; Nnanga, Nga; Sansebastiano, G E; Savino, A; Signorelli, C; Veronesi, L
2004-01-01
Microbial air contamination was evaluated in 11 operating theatres using active and passive samplings. SAS (Surface Air System) air sampling was used to evaluate cfu/m3 and settle plates were used to measure the index of microbial air contamination (IMA). Samplings were performed at the same time on three different days, at three different times (before, during and after the surgical activity). Two points were monitored (patient area and perimeter of the operating theatre). Moreover, the cfu/m3 were evaluated at the air inlet of the conditioner system. 74.7% of samplings performed at the air inlet and 66.7% of the samplings performed at the patient area before the beginning of the surgical activity (at rest) exceeded the 35 cfu/m3 used as threshold value. 100% of IMA values exceeded the threshold value of 5. Using both active and passive sampling, the microbial contamination was shown to increase significantly during activity. The cfu values were higher at the patient area than at the perimeter of the operating theatre. Mean values of the cfu/m3 during activity at the patient area ranged from a minimum of 61+/-41 cfu/m3 to a maximum of 242+/-136 cfu/m3; IMA values ranged from a minimum of 19+/-10 to a maximum of 129+/-60. 15.2% of samplings performed at the patient area using SAS and 75.8% of samplings performed using settle plates exceeded the threshold values of 180 cfu/m3 and 25 respectively, with a significant difference of the percentages. The highest values were found in the operating theatre with inadequate structural and managerial conditions. These findings confirm that the microbiological quality of air may be considered a mirror of the hygienic conditions of the operating theatre. Settle plates proved to be more sensitive in detecting the increase of microbial air contamination related to conditions that could compromise the quality of the air in operating theatres.
Investigation on thermal oxidative aging of nitrile rubber (NBR) O-rings under compression stress
NASA Astrophysics Data System (ADS)
Liu, X. R.; Zhang, W. F.; Lou, W. T.; Huang, Y. X.; Dai, W.
2017-11-01
The degradation behaviors of nitrile rubber O-rings exposure to air under compression were investigated at three elevated temperatures. The physical and mechanical properties of the aging samples before and after exposure at selected time were studied by measuring weight loss, tensile strength and elongation at break. The Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and fracture morphology were used to reveal the microstructural changes of the aging samples. The results indicate that the weight decreased with exposure time and temperature. Based on the results of the crosslinking density, the crosslinking predominates during the most of aging process. The significant changes in tensile strength and elongation at break also indicate the severe degradation in air. The fracture morphology results show that the fracture surface after 64 days of exposure to air turns rough and present defects. The ATR-FTIR results demonstrate that the hydroxyl groups were formed for the samples aged in air.
Luksamijarulkul, Pipat; Aiempradit, Natkitta; Vatanasomboon, Pisit
2014-01-01
Objective To assess the relationship of bacterial and fungal contamination on used surgical masks worn by the hospital personnel and microbial air quality in their working wards. Methods This is a cross-sectional study of 230 used surgical masks collected from 214 hospital personnel, and 215 indoor air samples collected from their working wards to culture for bacterial and fungal counts. This study was carried out at the hospital in Bangkok. Group or genus of isolated bacteria and fungi were preliminarily identified by Gram’s stain and lacto-phenol cotton blue. Data were analyzed using paired t-test and Pearson’s correlation coefficient at the significant level of p<0.050. Results Means and standard deviation of bacterial and fungal contamination on inside area of the used masks were 47 ± 56 and 15 ± 9 cfu/ml/piece, and on outside area were 166 ± 199 and 34 ± 18 cfu/ml/piece, respectively, p<0.001. The bacterial and fungal contamination on used masks from hospital personnel working in the male and female medical wards and out-patient department, as well as the bacterial and fungal counts of the indoor air sample collected from the same area were relatively higher than the other wards. The predominant isolated bacteria and fungi contaminated on inside and outside areas of the used masks and air samples were similar (Staphylococcus spp. and Aspergillus spp.; respectively). For its relationship, results found that bacterial and fungal counts in air samples showed significantly positive correlation with the bacterial contamination load on outside area of the used masks, r=0.16, p=0.018 and r=0.21, p=0.003, respectively. Conclusion High bacterial contamination on outside area of the used masks was demonstrated, and it showed a significant correlation with microbial air quality of working wards. PMID:25337311
Luksamijarulkul, Pipat; Aiempradit, Natkitta; Vatanasomboon, Pisit
2014-09-01
To assess the relationship of bacterial and fungal contamination on used surgical masks worn by the hospital personnel and microbial air quality in their working wards. This is a cross-sectional study of 230 used surgical masks collected from 214 hospital personnel, and 215 indoor air samples collected from their working wards to culture for bacterial and fungal counts. This study was carried out at the hospital in Bangkok. Group or genus of isolated bacteria and fungi were preliminarily identified by Gram's stain and lacto-phenol cotton blue. Data were analyzed using paired t-test and Pearson's correlation coefficient at the significant level of p<0.050. Means and standard deviation of bacterial and fungal contamination on inside area of the used masks were 47 ± 56 and 15 ± 9 cfu/ml/piece, and on outside area were 166 ± 199 and 34 ± 18 cfu/ml/piece, respectively, p<0.001. The bacterial and fungal contamination on used masks from hospital personnel working in the male and female medical wards and out-patient department, as well as the bacterial and fungal counts of the indoor air sample collected from the same area were relatively higher than the other wards. The predominant isolated bacteria and fungi contaminated on inside and outside areas of the used masks and air samples were similar (Staphylococcus spp. and Aspergillus spp.; respectively). For its relationship, results found that bacterial and fungal counts in air samples showed significantly positive correlation with the bacterial contamination load on outside area of the used masks, r=0.16, p=0.018 and r=0.21, p=0.003, respectively. High bacterial contamination on outside area of the used masks was demonstrated, and it showed a significant correlation with microbial air quality of working wards.
Jary, Hannah; Mallewa, Jane; Nyirenda, Mulinda; Faragher, Brian; Heyderman, Robert; Peterson, Ingrid; Gordon, Stephen; Mortimer, Kevin
2015-08-20
Pneumonia is the 2nd leading cause of years of life lost worldwide and is a common cause of adult admissions to hospital in sub-Saharan Africa. Risk factors for adult pneumonia are well characterised in developed countries, but are less well described in sub-Saharan Africa where HIV is a major contributing factor. Exposure to indoor and outdoor air pollution is high, and tobacco smoking prevalence is increasing in sub-Saharan Africa, yet the contribution of these factors to the burden of chronic respiratory diseases in sub-Saharan Africa remains poorly understood. Furthermore, the extent to which the presence of chronic respiratory diseases and exposure to air pollution contribute to the burden of pneumonia is not known. The Acute Infection of the Respiratory Tract Study (The AIR Study) is a case-control study to identify preventable risk factors for adult pneumonia in the city of Blantyre, Malawi. Cases will be adults admitted with pneumonia, recruited from Queen Elizabeth Central Hospital, the largest teaching hospital in Malawi. Controls will be adults without pneumonia, recruited from the community. The AIR Study will recruit subjects and analyse data within strata defined by positive and negative HIV infection status. All participants will undergo thorough assessment for a range of potential preventable risk factors, with an emphasis on exposure to air pollution and the presence of chronic respiratory diseases. This will include collection of questionnaire data, clinical samples (blood, urine, sputum and breath samples), lung function data and air pollution monitoring in their home. Multivariate analysis will be used to identify the important risk factors contributing to the pneumonia burden in this setting. Identification of preventable risk factors will justify research into the effectiveness of targeted interventions to address this burden in the future. The AIR Study is the first study of radiologically confirmed pneumonia in which air pollution exposure measurements have been undertaken in this setting, and will contribute important new information about exposure to air pollution in urban SSA. Through identification of preventable risk factors, the AIR Study aims to facilitate future research and implementation of targeted interventions to reduce the high burden of pneumonia in SSA.
NASA Astrophysics Data System (ADS)
Jia, Chunrong; Foran, Jeffery
2013-12-01
Southwest Memphis is a residential region surrounded by fossil fuel burning, steel, refining, and food processing industries, and considerable mobile sources whose emissions may pose adverse health risks to local residents. This study characterizes cancer and non-cancer risks resulting from exposure to ambient air toxics in southwest Memphis. Air toxics samples were collected at a central location every 6 days from June 5, 2008 to January 8, 2010. Volatile organic compounds (VOCs) were collected in evacuated stainless-steel canisters and aldehydes by DNPH cartridges, and samples were analyzed for 73 target compounds. A total of 60 compounds were detected and 39 were found in over 86% of the samples. Mean concentrations of many compounds were higher than those measured in many industrial communities throughout the U.S. The cumulative cancer risk associated with exposure to 13 carcinogens found in southwest Memphis air was 2.3 × 10-4, four times higher than the national average of 5.0 × 10-5. Three risk drivers were identified: benzene, formaldehyde, and acrylonitrile, which contributed 43%, 19%, and 14% to the cumulative risk, respectively. This is the first field study to confirm acrylonitrile as a potential risk driver. Mobile, secondary, industrial, and background sources contributed 57%, 24%, 14%, and 5% of the risk, respectively. The results of this study indicate that southwest Memphis, a region of significant income, racial, and social disparities, is also a region under significant environmental stress compared with surrounding areas and communities.
Tulum, Liz; Deag, Zoë; Brown, Matthew; Furniss, Annette; Meech, Lynn; Lalljie, Anja; Cochrane, Stella
2018-01-01
Exposure to airborne proteins can be associated with the development of immediate, IgE-mediated respiratory allergies, with genetic, epigenetic and environmental factors also playing a role in determining the likelihood that sensitisation will be induced. The main objective of this study was to determine whether airborne concentrations of selected common aeroallergens could be quantified in the air of homes using easily deployable, commercially available equipment and analytical methods, at low levels relevant to risk assessment of the potential to develop respiratory allergies. Additionally, air and dust sampling were compared and the influence of factors such as different filter types on allergen quantification explored. Low volume air sampling pumps and DUSTREAM ® dust samplers were used to sample 20 homes and allergen levels were quantified using a MARIA ® immunoassay. It proved possible to detect a range of common aeroallergens in the home with sufficient sensitivity to quantify airborne concentrations in ranges relevant to risk assessment (Limits of Detection of 0.005-0.03 ng/m 3 ). The methodology discriminates between homes related to pet ownership and there were clear advantages to sampling air over dust which are described in this paper. Furthermore, in an adsorption-extraction study, PTFE (polytetrafluoroethylene) filters gave higher and more consistent recovery values than glass fibre (grade A) filters for the range of aeroallergens studied. Very low airborne concentrations of allergenic proteins in home settings can be successfully quantified using commercially available pumps and immunoassays. Considering the greater relevance of air sampling to human exposure of the respiratory tract and its other advantages, wider use of standardised, sensitive techniques to measure low airborne protein concentrations and how they influence development of allergic sensitisation and symptoms could accelerate our understanding of human dose-response relationships and refine our knowledge of thresholds of allergic sensitisation and elicitation via the respiratory tract.
NASA Astrophysics Data System (ADS)
Zawadowicz, M. A.; Del Negro, L. A.
2010-12-01
Hazardous air pollutants (HAPs) are usually present in the atmosphere at pptv-level, requiring measurements with high sensitivity and minimal contamination. Commonly used evacuated canister methods require an overhead in space, money and time that often is prohibitive to primarily-undergraduate institutions. This study optimized an analytical method based on solid-phase microextraction (SPME) of ambient gaseous matrix, which is a cost-effective technique of selective VOC extraction, accessible to an unskilled undergraduate. Several approaches to SPME extraction and sample analysis were characterized and several extraction parameters optimized. Extraction time, temperature and laminar air flow velocity around the fiber were optimized to give highest signal and efficiency. Direct, dynamic extraction of benzene from a moving air stream produced better precision (±10%) than sampling of stagnant air collected in a polymeric bag (±24%). Using a low-polarity chromatographic column in place of a standard (5%-Phenyl)-methylpolysiloxane phase decreased the benzene detection limit from 2 ppbv to 100 pptv. The developed method is simple and fast, requiring 15-20 minutes per extraction and analysis. It will be field-validated and used as a field laboratory component of various undergraduate Chemistry and Environmental Studies courses.
Uhrbrand, K; Schultz, A C; Koivisto, A J; Nielsen, U; Madsen, A M
2017-04-01
Exposure to bioaerosols can pose a health risk to workers at wastewater treatment plants (WWTPs) and to habitants of their surroundings. The main objective of this study was to examine the presence of harmful microorganisms in the air emission from a new type of hospital WWTP employing advanced wastewater treatment technologies. Air particle measurements and sampling of inhalable bacteria, endotoxin and noroviruses (NoVs) were performed indoor at the WWTP and outside at the WWTP ventilation air exhaust, downwind of the air exhaust, and upwind of the WWTP. No significant differences were seen in particle and endotoxin concentrations between locations. Bacterial concentrations were comparable or significantly lower in the exhaust air than inside the WWTP and in the upwind reference. Bacterial isolates were identified using matrix-assisted laser desorption-ionization time-of-flight mass spectrometry. In total, 35 different bacterial genera and 64 bacterial species were identified in the air samples. Significantly higher genus and species richness was found with an Andersen Cascade Impactor compared with filter-based sampling. No pathogenic bacteria were found in the exhaust air. Streptomyces was the only bacterium found in the air both inside the WWTP and at the air emission, but not in the upwind reference. NoV genomes were detected in the air inside the WWTP and at the air exhaust, albeit in low concentrations. As only traces of NoV genomes could be detected in the exhaust air they are unlikely to pose a health risk to surroundings. Hence, we assess the risk of airborne exposure to pathogenic bacteria and NoVs from the WWTP air emission to surroundings to be negligible. However, as a slightly higher NoV concentration was detected inside the WWTP, we cannot exclude the possibility that exposure to airborne NoVs can pose a health risk to susceptible to workers inside the WWTP, although the risk may be low. Copyright © 2017 Elsevier Ltd. All rights reserved.
Sehmel, George A.
1979-01-01
An isokinetic air sampler includes a filter, a holder for the filter, an air pump for drawing air through the filter at a fixed, predetermined rate, an inlet assembly for the sampler having an inlet opening therein of a size such that isokinetic air sampling is obtained at a particular wind speed, a closure for the inlet opening and means for simultaneously opening the closure and turning on the air pump when the wind speed is such that isokinetic air sampling is obtained. A system incorporating a plurality of such samplers provided with air pumps set to draw air through the filter at the same fixed, predetermined rate and having different inlet opening sizes for use at different wind speeds is included within the ambit of the present invention as is a method of sampling air to measure airborne concentrations of particulate pollutants as a function of wind speed.
Almeida, Susana Marta; Lage, Joana; Freitas, Maria do Carmo; Pedro, Ana Isabel; Ribeiro, Tiago; Silva, Alexandra Viana; Canha, Nuno; Almeida-Silva, Marina; Sitoe, Timóteo; Dionisio, Isabel; Garcia, Sílvia; Domingues, Gonçalo; de Faria, Julia Perim; Fernández, Beatriz González; Ciaparra, Diane; Wolterbeek, Hubert T
2012-01-01
Throughout the world, epidemiological studies were established to examine the relationship between air pollution and mortality rates and adverse respiratory health effects. However, despite the years of discussion the correlation between adverse health effects and atmospheric pollution remains controversial, partly because these studies are frequently restricted to small and well-monitored areas. Monitoring air pollution is complex due to the large spatial and temporal variations of pollution phenomena, the high costs of recording instruments, and the low sampling density of a purely instrumental approach. Therefore, together with the traditional instrumental monitoring, bioindication techniques allow for the mapping of pollution effects over wide areas with a high sampling density. In this study, instrumental and biomonitoring techniques were integrated to support an epidemiological study that will be developed in an industrial area located in Gijon in the coastal of central Asturias, Spain. Three main objectives were proposed to (i) analyze temporal patterns of PM₁₀ concentrations in order to apportion emissions sources, (ii) investigate spatial patterns of lichen conductivity to identify the impact of the studied industrial area in air quality, and (iii) establish relationships amongst lichen conductivity with some site-specific characteristics. Samples of the epiphytic lichen Parmelia sulcata were transplanted in a grid of 18 by 20 km with an industrial area in the center. Lichens were exposed for a 5-mo period starting in April 2010. After exposure, lichen samples were soaked in 18-MΩ water aimed at determination of water electrical conductivity and, consequently, lichen vitality and cell damage. A marked decreasing gradient of lichens conductivity relative to distance from the emitting sources was observed. Transplants from a sampling site proximal to the industrial area reached values 10-fold higher than levels far from it. This finding showed that lichens reacted physiologically in the polluted industrial area as evidenced by increased conductivity correlated to contamination level. The integration of temporal PM₁₀ measurements and analysis of wind direction corroborated the importance of this industrialized region for air quality measurements and identified the relevance of traffic for the urban area.
Rock, Clare; Harris, Anthony D; Johnson, J Kristie; Bischoff, Werner E; Thom, Kerri A
2015-07-01
Using a validated air sampling method we found Acinetobacter baumannii in the air surrounding only 1 of 12 patients known to be colonized or infected with A. baumannii. Patients' closed-circuit ventilator status, frequent air exchanges in patient rooms, and short sampling time may have contributed to this low burden.
Davari, Abdolrahim; Mousvinasab, Majid; Kazemi, Alireza Danesh; Rouzbeh, Reza
2013-01-01
Solvent content of a contemporary dental adhesive affect the bonding process, especially in the case of acetone based adhesives. The aim of this study was to evaluate the effect of different air-drying periods on microtensile bond strength (MTBS) of a total-etch adhesive to dentin. Prime & Bond NT (Dentsply-USA) was used with different air-drying periods (0, 2, 5, 10, 30sec) for bonding a composite resin to prepared dentin. The specimens were then subjected to a tensile force until fracture and the MTBSs of the samples were recorded. Failure modes of the fractured samples were also determined using stereomicroscope and scanning electron microscopy. Data were analyzed using ANOVA and Bonferroni tests (P = 0.05). With increasing the air-drying periods, the MTBSs were increased until the 5 second air-blowing; after that, with increasing the air-drying periods, the MTBSs decreased. Both, the most complicated failure and the strongest bond were seen in the 5 sec air-drying group. There is an optimum air-drying time for acetone based adhesives which results in the strongest bond to dentin.
Astorga, Berbeli; Lorenzo-Morales, Jacob; Martín-Navarro, Carmen M; Alarcón, Verónica; Moreno, Johanna; González, Ana C; Navarrete, Elizabeth; Piñero, José E; Valladares, Basilio
2011-01-01
Free-living amoebae (FLA) of the genus Acanthamoeba are widely distributed in the environment, in the air, soil, and water, and have also been isolated from air-conditioning units. The objective of this work was to investigate the presence of this genus of FLA in the air-conditioning equipment at the Institute of Public Health of Chile in Santiago, Chile. Water and air samples were collected from air-conditioning systems and were checked for the presence of Acanthamoeba spp. Positive samples were further classified at the genotype level after sequencing the highly variable diagnostic fragment 3 (DF3) region of the 18S rRNA gene. This is the first report of the T3, T4, and T11 genotypes of Acanthamoeba in air-conditioning units from Chile. Overall, the widespread distribution of potentially pathogenic Acanthamoeba strains in the studied source demands more awareness within the public and health professionals in Chile as this pathogen is emerging as a risk for human health worldwide. © 2011 The Author(s) Journal of Eukaryotic Microbiology © 2011 International Society of Protistologists.
Microbial air quality and bacterial surface contamination in ambulances during patient services.
Luksamijarulkul, Pipat; Pipitsangjan, Sirikun
2015-03-01
We sought to assess microbial air quality and bacterial surface contamination on medical instruments and the surrounding areas among 30 ambulance runs during service. We performed a cross-sectional study of 106 air samples collected from 30 ambulances before patient services and 212 air samples collected during patient services to assess the bacterial and fungal counts at the two time points. Additionally, 226 surface swab samples were collected from medical instrument surfaces and the surrounding areas before and after ambulance runs. Groups or genus of isolated bacteria and fungi were preliminarily identified by Gram's stain and lactophenol cotton blue. Data were analyzed using descriptive statistics, t-test, and Pearson's correlation coefficient with a p-value of less than 0.050 considered significant. The mean and standard deviation of bacterial and fungal counts at the start of ambulance runs were 318±485cfu/m(3) and 522±581cfu/m(3), respectively. Bacterial counts during patient services were 468±607cfu/m(3) and fungal counts were 656±612cfu/m(3). Mean bacterial and fungal counts during patient services were significantly higher than those at the start of ambulance runs, p=0.005 and p=0.030, respectively. For surface contamination, the overall bacterial counts before and after patient services were 0.8±0.7cfu/cm(2) and 1.3±1.1cfu/cm(2), respectively (p<0.001). The predominant isolated bacteria and fungi were Staphylococcus spp. and Aspergillus spp., respectively. Additionally, there was a significantly positive correlation between bacterial (r=0.3, p<0.010) and fungal counts (r=0.2, p=0.020) in air samples and bacterial counts on medical instruments and allocated areas. This study revealed high microbial contamination (bacterial and fungal) in ambulance air during services and higher bacterial contamination on medical instrument surfaces and allocated areas after ambulance services compared to the start of ambulance runs. Additionally, bacterial and fungal counts in ambulance air showed a significantly positive correlation with the bacterial surface contamination on medical instruments and allocated areas. Further studies should be conducted to determine the optimal intervention to reduce microbial contamination in the ambulance environment.
Airsheds, Isotopes and Ecosystem Metabolism in Mountainous Terrain
NASA Astrophysics Data System (ADS)
Sulzman, E.; Barnard, H.; Bond, B. J.; Czarnomski, N. M.; Hauck, M.; Kayler, Z.; Mix, A. C.; Pypker, T.; Rugh, W.; Unsworth, M.
2005-12-01
At least 20% of the terrestrial surface of the earth is covered by mountains, which contain many of the world's most productive ecosystems. Interactions between vegetation and the physical environment are often very different in mountains than on flat land. However, few studies have addressed these unique interactions, and many of the tools used to measure and monitor ecosystem metabolism are difficult or impossible to use in complex, mountainous terrain. In a project we call the "Andrews Airshed study" located in western Oregon Cascades, we aim to identify and explore sources of variation in the isotopic composition of ecosystem respiration (δ13CR-eco) and airflow patterns in cold-air drainage, with the eventual aim of "inverting" this understanding so that we can use δ13CR-eco to monitor intra- and inter-annual variations in ecosystem metabolism on a basin scale. We are measuring patterns of airflow, quantifying the CO2 concentration in the flow, and measuring the carbon isotope composition of ecosystem-respired CO2 as well as soil-respired CO2 (δ13CR-soil), which accounts for more than half of δ13CR-eco. We have designed an automated air sampling device that we programmed to sample air at 10 ppm intervals from 30 m above the stream in our 100 ha, deeply-incised watershed. Samples are collected via Valco valves into stainless steel tubing that can be connected directly to an isotope ratio mass spectrometer. We also designed and installed soil gas sampling probes, which are located in five 10 m2 sampling plots from ridge top to valley floor to the opposite ridge top. Weekly samples (May-Sept, 2005) of air from soil and the nocturnal air flow show seasonal variation in δ13CR-eco over a 2 per mil range, with more enriched values corresponding to lower soil moisture. Soil-respired CO2 also reveal seasonality and are isotopically enriched compared with above-ground air. δ13CR-soil values from north- and south-facing slopes of the watershed differ by 1 per mil, with south-facing values consistently enriched relative to those of the north-facing slope. We are concurrently conducting studies to determine the appropriate footprint of respired CO2 in the nocturnal airstream, which will allow us to overlay the data properly.
NHEXAS PHASE I REGION 5 STUDY--QA ANALYTICAL RESULTS FOR VOCS IN BLANKS
This data set includes analytical results for measurements of VOCs in 88 blank samples. Measurements were made for up to 23 VOCs in blank samples of air, water, and blood. Blank samples were used to assess the potential for sample contamination during collection, storage, shipmen...
NHEXAS PHASE I ARIZONA STUDY--QA ANALYTICAL RESULTS FOR PESTICIDES IN BLANK SAMPLES
The Pesticides in Blank Samples data set contains the analytical results of measurements of up to 4 pesticides in 43 blank samples from 29 households. Measurements were made in blank samples of dust, indoor and outdoor air, food and beverages, blood, urine, and dermal wipe resid...
NHEXAS PHASE I MARYLAND STUDY--QA ANALYTICAL RESULTS FOR METALS IN REPLICATE SAMPLES
The Metals in Replicates data set contains the analytical results of measurements of up to 11 metals in 88 replicate (duplicate) samples from 52 households. Measurements were made in samples of indoor and outdoor air, drinking water, food, and beverages. Duplicate samples for a...
Air Sample Conditioner Helps the Waste Treatment Plant Meet Emissions Standards
DOE Office of Scientific and Technical Information (OSTI.GOV)
Glissmeyer, John A.; Flaherty, Julia E.; Pekour, Mikhail S.
2014-12-02
The air in three of the Hanford Site Waste Treatment and Immobilization Plant (WTP) melter off-gas discharge stacks will be hot and humid after passing through the train of emission abatement equipment. The off-gas temperature and humidity levels will be incompatible with the airborne emissions monitoring equipment required for this type of stack. To facilitate sampling from these facilities, an air sample conditioner system will be installed to introduce cool, dry air into the sample stream to reduce the temperature and dew point. This will avoid thermal damage to the instrumentation and problematic condensation. The complete sample transport system mustmore » also deliver at least 50% of the particles in the sample airstream to the sample collection and on-line analysis equipment. The primary components of the sample conditioning system were tested in a laboratory setting. The sample conditioner itself is based on a commercially-available porous tube filter design. It consists of a porous sintered metal tube inside a coaxial metal jacket. The hot gas sample stream passes axially through the porous tube, and the dry, cool air is injected into the jacket and through the porous wall of the inner tube, creating an effective sample diluter. The dilution and sample air mix along the entire length of the porous tube, thereby simultaneously reducing the dew point and temperature of the mixed sample stream. Furthermore, because the dilution air enters through the porous tube wall, the sample stream does not come in contact with the porous wall and particle deposition is reduced in this part of the sampling system. Tests were performed with an environmental chamber to supply air with the temperature and humidity needed to simulate the off-gas conditions. Air from the chamber was passed through the conditioning system to test its ability to reduce the temperature and dew point of the sample stream. To measure particle deposition, oil droplets in the range of 9 to 11 micrometer aerodynamic diameter were injected into the environmental chamber and drawn through the conditioning system, which included a filter to capture droplets that passed through the conditioner. The droplets were tagged with a fluorescent dye which allowed quantification of droplet deposition on each component of the system. The tests demonstrated the required reductions in temperature and moisture, with no condensation forming when heat tracing was added on the upstream end of the sample conditioner. Additionally, tests indicated that the system, operating at several flow rates and in both vertical and horizontal orientations, delivers nearly all of the sampled particles for analysis. Typical aerosol penetration values were between 98 and 99%. PNNL, Bechtel National Inc., and the instrument vendor are working to implement the sample conditioner into the air monitoring systems used for the melter off-gas exhaust streams. Similar technology may be useful for processes in other facilities with air exhaust streams with elevated temperature and/or humidity.« less
Najotra, Dipender Kaur; Malhotra, Aneeta Singh; Slathia, Poonam; Raina, Shivani; Dhar, Ashok
2017-01-01
Introduction: Microbiological contamination of air and environment in the operation theaters (OTs) are major risk factor for surgical site and other hospital-associated infections. Objectives: The aim was to identify bacterial colonization of surfaces and equipment and to determine the microbial contamination of air in the OTs of a tertiary care hospital. Materials and Methods: Five years (January 2010–December 2014) retrospective analysis of the data obtained from routine microbiological surveillance of the five OTs of the hospital was done. Surface samples were taken with wet swabs from different sites and equipment. Bacterial species were isolated and identified by conventional methods. Air quality surveillance of OTs was done by settle plate method. Results: A total of 4387 samples were collected from surfaces and articles of various OTs. Out of these only 195 (4.4%), samples showed bacterial growth and yielded 210 isolates. The predominant species isolated was Bacillus with 184 (87.6%) isolates followed by coagulase-negative Staphylococcus 17 (8.1%), Staphylococcus aureus 6 (2.9%), and Enteroccoccus spp. 3 (1.4%). Analysis of the OT air samples showed least colony forming unit (cfu) rate of air (27 cfu/m3) in ophthalmology OT and highest rate of 133 cfu/m3 in general surgery OT. Conclusion: The study shows that OTs of our hospital showed a very low bacterial contamination rate on surface swabbing and a cfu count per m3 of air well within permissible limits. PMID:28904915
McKernan, Lauralynn Taylor; Burge, Harriet; Wallingford, Kenneth M; Hein, Misty J; Herrick, Robert
2007-04-01
Given the potential health effects of fungi and the amount of time aircrew and passengers spend inside aircraft, it is important to study fungal populations in the aircraft environment. Research objectives included documenting the genera/species of airborne culturable fungal concentrations and total spore concentrations on a twin-aisle wide body commercial passenger aircraft. Twelve flights between 4.5 and 6.5 h in duration on Boeing 767 (B-767) aircraft were evaluated. Two air cooling packs and 50% recirculation rate (i.e. 50:50 mix of outside air and filtered inside air) were utilized during flight operations. Passenger occupancy rates varied from 67 to 100%. N-6 impactors and total spore traps were used to collect sequential, triplicate air samples in the front and rear of coach class during six sampling intervals throughout each flight: boarding, mid-climb, early cruise, mid-cruise, late cruise and deplaning. Comparison air samples were also collected inside and outside the airport terminals at the origin and destination cities resulting in a total of 522 culturable and 517 total spore samples. A total of 45 surface wipe samples were collected using swabs onboard the aircraft and inside the airport terminals. A variety of taxa were observed in the culturable and total spore samples. A frequency analysis of the fungal data indicated that Cladosporium, Aspergillus and Penicillium were predominant genera in the culturable samples whereas Cladosporium, Basidiospores and Penicillium/Aspergillus were predominant in the total spore samples. Fungal populations observed inside the aircraft were comprised of similar genera, detected significantly less frequently and with lower mean concentrations than those observed in typical office buildings. Although sources internal to the aircraft could not be ruled out, our data demonstrate the importance of passenger activity as the source of the fungi observed on aircraft. Isolated fungal peak events occurred occasionally when concentrations of a particular genus or species rose sharply inside the cabin for a limited period. Overall, our research demonstrates that on the sampled flights the B-767 filtration system operated efficiently to remove fungal spores when two air cooling packs and 50% recirculation rate were utilized during flight operations.
NASA Astrophysics Data System (ADS)
Wentworth, Gregory R.; Aklilu, Yayne-abeba; Landis, Matthew S.; Hsu, Yu-Mei
2018-04-01
During May 2016 a very large boreal wildfire burned throughout the Athabasca Oil Sands Region (AOSR) in central Canada, and in close proximity to an extensive air quality monitoring network. This study examines speciated 24-h integrated polycyclic aromatic hydrocarbon (PAH) and volatile organic compound (VOC) measurements collected every sixth day at four and seven sites, respectively, from May to August 2016. The sum of PAHs (ΣPAH) was on average 17 times higher in fire-influenced samples (852 ng m-3, n = 8), relative to non-fire influenced samples (50 ng m-3, n = 64). Diagnostic PAH ratios in fire-influenced samples were indicative of a biomass burning source, whereas ratios in June to August samples showed additional influence from petrogenic and fossil fuel combustion. The average increase in the sum of VOCs (ΣVOC) was minor by comparison: 63 ppbv for fire-influenced samples (n = 16) versus 46 ppbv for non-fire samples (n = 90). The samples collected on August 16th and 22nd had large ΣVOC concentrations at all sites (average of 123 ppbv) that were unrelated to wildfire emissions, and composed primarily of acetaldehyde and methanol suggesting a photochemically aged air mass. Normalized excess enhancement ratios (ERs) were calculated for 20 VOCs and 23 PAHs for three fire influenced samples, and the former were generally consistent with previous observations. To our knowledge, this is the first study to report ER measurements for a number of VOCs and PAHs in fresh North American boreal wildfire plumes. During May the aged wildfire plume intercepted the cities of Edmonton (∼380 km south) or Lethbridge (∼790 km south) on four separate occasions. No enhancement in ground-level ozone (O3) was observed in these aged plumes despite an assumed increase in O3 precursors. In the AOSR, the only daily-averaged VOCs which approached or exceeded the hourly Alberta Ambient Air Quality Objectives (AAAQOs) were benzene (during the fire) and acetaldehyde (on August 16th and 22nd). Implications for local and regional air quality as well as suggestions for supplemental air monitoring during future boreal fires, are also discussed.
Napoli, C; Tafuri, S; Montenegro, L; Cassano, M; Notarnicola, A; Lattarulo, S; Montagna, M T; Moretti, B
2012-02-01
To evaluate the level of microbial contamination of air in operating theatres using active [i.e. surface air system (SAS)] and passive [i.e. index of microbial air contamination (IMA) and nitrocellulose membranes positioned near the wound] sampling systems. Sampling was performed between January 2010 and January 2011 in the operating theatre of the orthopaedics department in a university hospital in Southern Italy. During surgery, the mean bacterial loads recorded were 2232.9 colony-forming units (cfu)/m(2)/h with the IMA method, 123.2 cfu/m(3) with the SAS method and 2768.2 cfu/m(2)/h with the nitrocellulose membranes. Correlation was found between the results of the three methods. Staphylococcus aureus was detected in 12 of 60 operations (20%) with the membranes, five (8.3%) operations with the SAS method, and three operations (5%) with the IMA method. Use of nitrocellulose membranes placed near a wound is a valid method for measuring the microbial contamination of air. This method was more sensitive than the IMA method and was not subject to any calibration bias, unlike active air monitoring systems. Copyright © 2011 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
Innovations in Site Characterization Case Study: Hanscom Air Force Base, Operable Unit 1
This document is a condensation of the information provided in the much more detailed Hanscom AFB Report entitled A Dynamic Site Investigation: Adaptive Sampling and Analysis Program for Operable Unit 1 at Hanscom Air Force Base, Bedford, Massachusetts.
Multiple site receptor modeling with a minimal spanning tree combined with a Kohonen neural network
NASA Astrophysics Data System (ADS)
Hopke, Philip K.
1999-12-01
A combination of two pattern recognition methods has been developed that allows the generation of geographical emission maps form multivariate environmental data. In such a projection into a visually interpretable subspace by a Kohonen Self-Organizing Feature Map, the topology of the higher dimensional variables space can be preserved, but parts of the information about the correct neighborhood among the sample vectors will be lost. This can partly be compensated for by an additional projection of Prim's Minimal Spanning Tree into the trained neural network. This new environmental receptor modeling technique has been adapted for multiple sampling sites. The behavior of the method has been studied using simulated data. Subsequently, the method has been applied to mapping data sets from the Southern California Air Quality Study. The projection of a 17 chemical variables measured at up to 8 sampling sites provided a 2D, visually interpretable, geometrically reasonable arrangement of air pollution source sin the South Coast Air Basin.
Alpha-environmental continuous air monitor inlet
Rodgers, John C.
2003-01-01
A wind deceleration and protective shroud that provides representative samples of ambient aerosols to an environmental continuous air monitor (ECAM) has a cylindrical enclosure mounted to an input on the continuous air monitor, the cylindrical enclosure having shrouded nozzles located radially about its periphery. Ambient air flows, often along with rainwater flows into the nozzles in a sampling flow generated by a pump in the continuous air monitor. The sampling flow of air creates a cyclonic flow in the enclosure that flows up through the cylindrical enclosure until the flow of air reaches the top of the cylindrical enclosure and then is directed downward to the continuous air monitor. A sloped platform located inside the cylindrical enclosure supports the nozzles and causes any moisture entering through the nozzle to drain out through the nozzles.
Improved Atmospheric Sampling of Hexavalent Chromium
Torkmahalleh, Mehdi Amouei; Yu, Chang-Ho; Lin, Lin; Fan, Zhihua (Tina); Swift, Julie L.; Bonanno, Linda; Rasmussen, Don H.; Holsen, Thomas M.; Hopke, Philip K.
2015-01-01
Hexavalent chromium (Cr(VI)) and trivalent chromium (Cr(III)) are the primary chromium oxidation states found in ambient atmospheric particulate matter. While Cr(III) is relatively nontoxic, Cr(VI) is toxic and exposure to Cr(VI) may lead to cancer, nasal damage, asthma, bronchitis, and pneumonitis. Accurate measurement of the ambient Cr(VI) concentrations is an environmental challenge since Cr(VI) can be reduced to Cr(III) and vice versa during sampling. In the present study, a new Cr(VI) sampler (Clarkson sampler) was designed, constructed, and field tested to improve the sampling of Cr(VI) in ambient air. The new Clarkson Cr(VI) sampler was based on the concept that deliquescence during sampling leads to aqueous phase reactions. Thus, the relative humidity of the sampled air was reduced below the deliquescence relative humidity (DRH) of the ambient particles. The new sampler was operated to collect Total Suspended Particles (TSP), and compared side-by-side with the current National Air Toxics Trends Stations (NATTS) Cr(VI) sampler that is utilized in the United States Environmental Protection Agency (USEPA) air toxics monitoring program. Side-by-side field testing of the samplers occurred in Elizabeth, NJ during the winter and summer of 2012. The average recovery values of Cr(VI) spikes after 24 hour sampling intervals during summer and winter sampling were 57 and 72%, respectively, for the Clarkson sampler, while the corresponding average values for NATTS samplers were 46% for both summer and winter sampling, respectively. Preventing the ambient aerosol collected on the filters from deliquescing is a key to improving the sampling of Cr(VI). PMID:24344574
LeBouf, Ryan F; Virji, Mohammed Abbas; Ranpara, Anand; Stefaniak, Aleksandr B
2017-07-01
This method was designed for sampling select quaternary ammonium (quat) compounds in air or on surfaces followed by analysis using ultraperformance liquid chromatography tandem mass spectrometry. Target quats were benzethonium chloride, didecyldimethylammonium bromide, benzyldimethyldodecylammonium chloride, benzyldimethyltetradecylammonium chloride, and benzyldimethylhexadecylammonium chloride. For air sampling, polytetrafluoroethylene (PTFE) filters are recommended for 15-min to 24-hour sampling. For surface sampling, Pro-wipe® 880 (PW) media was chosen. Samples were extracted in 60:40 acetonitrile:0.1% formic acid for 1 hour on an orbital shaker. Method detection limits range from 0.3 to 2 ng/ml depending on media and analyte. Matrix effects of media are minimized through the use of multiple reaction monitoring versus selected ion recording. Upper confidence limits on accuracy meet the National Institute for Occupational Safety and Health 25% criterion for PTFE and PW media for all analytes. Using PTFE and PW analyzed with multiple reaction monitoring, the method quantifies levels among the different quats compounds with high precision (<10% relative standard deviation) and low bias (<11%). The method is sensitive enough with very low method detection limits to capture quats on air sampling filters with only a 15-min sample duration with a maximum assessed storage time of 103 days before sample extraction. This method will support future exposure assessment and quantitative epidemiologic studies to explore exposure-response relationships and establish levels of quats exposures associated with adverse health effects. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
Improvement of a wind-tunnel sampling system for odour and VOCs.
Wang, X; Jiang, J; Kaye, R
2001-01-01
Wind-tunnel systems are widely used for collecting odour emission samples from surface area sources. Consequently, a portable wind-tunnel system was developed at the University of New South Wales that was easy to handle and suitable for sampling from liquid surfaces. Development work was undertaken to ensure even air-flows above the emitting surface and to optimise air velocities to simulate real situations. However, recovery efficiencies for emissions have not previously been studied for wind-tunnel systems. A series of experiments was carried out for determining and improving the recovery rate of the wind-tunnel sampling system by using carbon monoxide as a tracer gas. It was observed by mass balance that carbon monoxide recovery rates were initially only 37% to 48% from a simulated surface area emission source. It was therefore apparent that further development work was required to improve recovery efficiencies. By analysing the aerodynamic character of air movement and CO transportation inside the wind-tunnel, it was determined that the apparent poor recoveries resulted from uneven mixing at the sample collection point. A number of modifications were made for the mixing chamber of the wind-tunnel system. A special sampling chamber extension and a sampling manifold with optimally distributed sampling orifices were developed for the wind-tunnel sampling system. The simulation experiments were repeated with the new sampling system. Over a series of experiments, the recovery efficiency of sampling was improved to 83-100% with an average of 90%, where the CO tracer gas was introduced at a single point and 92-102% with an average of 97%, where the CO tracer gas was introduced along a line transverse to the sweep air. The stability and accuracy of the new system were determined statistically and are reported.
NASA Astrophysics Data System (ADS)
Geesey, Mary Sophia
Polybrominated diphenyl ethers (PBDEs) have been used as flame retardants in a number of common household and commercial products around the world. PBDEs enter the environment in a variety of ways, such as through emissions, leaching from end-of-life electronics in landfills, and incineration. While many countries have phased out the manufacturing of penta-, octa-, and deca-PBDEs or have banned the manufacture and use of these congeners altogether, these persistent organic pollutants (POPs) continue to be detected in humans and the environment. This study investigates spatial and temporal variations of selected PBDEs in the air of the Nandamojo watershed area in Costa Rica by comparing air concentrations of PBDEs in the dry winter vs. wet summer seasons and rural vs. urban areas and also investigates the impact of anthropogenic activities on air concentration of PBDEs. This study is significant to the field, because there are no baseline studies nor are there currently any monitoring programs to assess the environmental levels of PBDEs or other POPs for this region of the Guanacaste province. Baseline information is needed to track spatial and temporal trends as well as evaluate the effectiveness of control measures employed nationally and internationally. Samples obtained from passive air sampling devices were analyzed via GC/MS for a number of congeners. PBDE-47 and -99 were found to be the congeners present in greatest concentration in air samples from the Nandamojo watershed area. Air concentrations were estimated assuming an average sampler uptake rate of 3.5 m3/day and ranged as follows: SigmaPBDE5 35.20-1549.25 pg/m3 over the entire study. The presence of PBDEs in remote and pristine environments indicates that PBDEs are now a global concern. This study suggests that the spatial and temporal distribution patterns observed are strongly related to anthropogenic activities and presence of a population similar to that observed in other studies. The presence of PBDEs has become a global issue and, as such, these results provide background information on air concentrations of PBDEs for use in a global-scale multimedia model. In order to monitor PBDEs globally, it is imperative to implement and/or expand surveillance programs internationally.
NASA Astrophysics Data System (ADS)
Capuano, Rosamaria; Santonico, Marco; Pennazza, Giorgio; Ghezzi, Silvia; Martinelli, Eugenio; Roscioni, Claudio; Lucantoni, Gabriele; Galluccio, Giovanni; Paolesse, Roberto; di Natale, Corrado; D'Amico, Arnaldo
2015-11-01
Results collected in more than 20 years of studies suggest a relationship between the volatile organic compounds exhaled in breath and lung cancer. However, the origin of these compounds is still not completely elucidated. In spite of the simplistic vision that cancerous tissues in lungs directly emit the volatile metabolites into the airways, some papers point out that metabolites are collected by the blood and then exchanged at the air-blood interface in the lung. To shed light on this subject we performed an experiment collecting both the breath and the air inside both the lungs with a modified bronchoscopic probe. The samples were measured with a gas chromatography-mass spectrometer (GC-MS) and an electronic nose. We found that the diagnostic capability of the electronic nose does not depend on the presence of cancer in the sampled lung, reaching in both cases an above 90% correct classification rate between cancer and non-cancer samples. On the other hand, multivariate analysis of GC-MS achieved a correct classification rate between the two lungs of only 76%. GC-MS analysis of breath and air sampled from the lungs demonstrates a substantial preservation of the VOCs pattern from inside the lung to the exhaled breath.
The purpose of this SOP is to describe the acid digestion of soil, house dust, air filter, and surface or dermal wipe samples for analysis using inductively coupled plasma atomic emissions spectrometry (ICP-AES) and/or graphite furnace atomic absorption spectrometry (GFAAS) or fl...
Stratospheric Trace Gas Composition Studies Utilizing in situ Cryogenic, Whole-Air Sampling Methods.
1981-03-10
C A FORSBERG, R V PIERI UNCLASSIFIED AFGL-TR-81-0071 NLEEEE..EEEEEEllllllu *Inaggol/numln ElhElhEEEEEEEI lllllllhhl , O \\ Stratospheric Trace Gas...GRANT NUJMBERr4; Charles A. Forsberg Robert V. Pieri , Capt., USAF Gerard A. Faucher B PERFORMING ORGANIZATION NAME AND ADDRESS IS. PROGRAM ELEMENT...launch site. 1 (Received for publication 10 March 1981) 1. Gallagher, C.(C., and Pieri , R. V. (1976) Cryogenic, Whole-Air Sampl1r and Program for
Characterisation of Arctic Bacterial Communities in the Air above Svalbard
Cuthbertson, Lewis; Amores-Arrocha, Herminia; Malard, Lucie A.; Els, Nora; Sattler, Birgit; Pearce, David A.
2017-01-01
Atmospheric dispersal of bacteria is increasingly acknowledged as an important factor influencing bacterial community biodiversity, biogeography and bacteria–human interactions, including those linked to human health. However, knowledge about patterns in microbial aerobiology is still relatively scarce, and this can be attributed, in part, to a lack of consensus on appropriate sampling and analytical methodology. In this study, three different methods were used to investigate aerial biodiversity over Svalbard: impaction, membrane filtration and drop plates. Sites around Svalbard were selected due to their relatively remote location, low human population, geographical location with respect to air movement and the tradition and history of scientific investigation on the archipelago, ensuring the presence of existing research infrastructure. The aerial bacterial biodiversity found was similar to that described in other aerobiological studies from both polar and non-polar environments, with Proteobacteria, Actinobacteria, and Firmicutes being the predominant groups. Twelve different phyla were detected in the air collected above Svalbard, although the diversity was considerably lower than in urban environments elsewhere. However, only 58 of 196 bacterial genera detected were consistently present, suggesting potentially higher levels of heterogeneity. Viable bacteria were present at all sampling locations, showing that living bacteria are ubiquitous in the air around Svalbard. Sampling location influenced the results obtained, as did sampling method. Specifically, impaction with a Sartorius MD8 produced a significantly higher number of viable colony forming units (CFUs) than drop plates alone. PMID:28481257
Hines, Cynthia J; Jackson, Matthew V; Christianson, Annette L; Clark, John C; Arnold, James E; Pretty, Jack R; Deddens, James A
2017-11-01
For decades, bisphenol A (BPA) has been used in making polycarbonate, epoxy, and phenolic resins and certain investment casting waxes, yet published exposure data are lacking for U.S. manufacturing workers. In 2013-2014, BPA air and hand exposures were quantified for 78 workers at six U.S. companies making BPA or BPA-based products. Exposure measures included an inhalable-fraction personal air sample on each of two consecutive work days (n = 146), pre- and end-shift hand wipe samples on the second day (n = 74 each), and surface wipe samples (n = 88). Potential determinants of BPA air and end-shift hand exposures (after natural log transformation) were assessed in univariate and multiple regression mixed models. The geometric mean (GM) BPA air concentration was 4.0 µg/m 3 (maximum 920 µg/m 3 ). The end-shift GM BPA hand level (26 µg/sample) was 10-times higher than the pre-shift level (2.6 µg/sample). BPA air and hand exposures differed significantly by industry and job. BPA air concentrations and end-shift hand levels were highest in the BPA-filled wax manufacturing/reclaim industry (GM Air = 48 µg/m 3 , GM Hand-End = 130 µg/sample) and in the job of working with molten BPA-filled wax (GM Air = 43 µg/m 3 , GM Hand-End = 180 µg/sample), and lowest in the phenolic resins industry (GM Air = 0.85 µg/m 3 , GM Hand-End = 0.43 µg/sample) and in the job of flaking phenolic resins (GM AIR = 0.62 µg/m 3 , GM Hand-End = 0.38 µg/sample). Determinants of increased BPA air concentration were industry, handling BPA containers, spilling BPA, and spending ≥50% of the shift in production areas; increasing age was associated with lower air concentrations. BPA hand exposure determinants were influenced by high values for two workers; for all other workers, tasks involving contact with BPA-containing materials and spending ≥50% of the shift in production areas were associated with increased BPA hand levels. Surface wipe BPA levels were significantly lower in eating/office areas (GM = 9.3 µg/100 cm 2 ) than in production areas (GM = 140 µg/100 cm 2 ). In conclusion, worker BPA exposure was associated with tasks and conditions affecting both inhalation and dermal exposure. The potential for BPA-related health effects among these workers is unknown.
A BATTERY-OPERATED AIR SAMPLER FOR REMOTE AREAS
An air sampling system developed to evaluate air quality in biosphere reserves or in other remote areas is described. The equipment consists of a Dupont P-4000 pump and a specially designed battery pack containing Gates batteries. This air sampling system was tested in Southern U...
Biobriefcase aerosol collector heater
Bell, Perry M [Tracy, CA; Christian, Allen T [Madison, WI; Bailey, Christopher G [Pleasanton, CA; Willis, Ladona [Manteca, CA; Masquelier, Donald A [Tracy, CA; Nasarabadi, Shanavaz L [Livermore, CA
2009-03-17
A system for sampling air and collecting particles potentially including bioagents entrained in the air for detection. The system comprises collecting a sample of the air with the particles entrained in the air, directing the sample to a receiving surface, directing a liquid to the receiving surface thereby producing a liquid surface, wherein the particles potentially including bioagents become captured in the liquid, and heating the liquid wherein the particles potentially including bioagents become heated to lysis the bioagents.
Song, Jing; Wei, Ling; Ma, Ying; Tian, Ning; Huang, Shi Yun; Dai, Yin Mei; Zhao, Li Hong; Kong, Yuan Yuan
2017-01-01
Introduction The association between early exposure to ambient air pollution and adverse pregnancy outcomes in China is unclear. This study will assess the risk of early-life exposure to air pollutants in Beijing and explore the viability of 8-hydroxydeoxyguanosine (8-OHdG) as a biological indicator to assess oxidative stress induced by early-life exposure to air pollution. Methods and analysis Here, 2500 women with singleton pregnancies and their infants will be recruited from the Beijing Obstetrics and Gynecology Hospital. We will collect nine types of biological samples, including maternal serum, urine, placental tissue, umbilical cord tissue and umbilical cord blood during all three trimesters. The air pollution data (particulate matter (PM)2.5, PM10 and similar factors) will be recorded at official fixed-site monitoring stations closest to where the pregnant women live. We plan to assess the effect of air pollutants on adverse pregnancy outcomes and infant respiratory and circulatory disease using Cox regression and competitive risk analysis and explore possible critical windows of exposure during pregnancy using daily pollutant concentrations averaged over various periods of pregnancy combined with individual activity and physiological parameters. Maternal and umbilical cord blood samples (1000 samples) will be randomly selected for 8-OHdG assays to assess the correlation between exposures to air pollutants and oxidative stress. We will determine whether air pollutant exposure or 8-OHdG levels are associated with adverse pregnancy outcomes. SPSS and SAS statistical software will be used for data analysis. Cox regression and competing risk analysis will be used to compute the HR and population attributable risk. Ethics and dissemination This research protocol has already been approved by the Medical Ethics Committee of Beijing Obstetrics and Gynecology Hospital. Written informed consent will be obtained from all study participants prior to enrolment. The results will be published in peer-reviewed journals or disseminated through conference presentations. Trial registration number This study has been registered in WHO International Clinical Trial Register—Chinese Clinical Trial Registry under registration number ChiCTR-ROC-16010181 (http :// www.chictr.org.cn / showproj.aspx ?proj=17328). PMID:28871018
Air sampling experiments were done in 1985, 1987, and 1993 at the human-exposure chamber facility of the U.S. EPA Health Effects Research Laboratory in Chapel Hill, NC. easurements of VOC's by GC-FID and aldehyde measurements by the DNPH silica gel cartridge method were made, com...
Evaluation of Environmental Profiles for Reliability Demonstration
1975-09-01
the increase in the ram air flow rate. As a result, one cannot generalize in advance about the effect of velocity increase on air-conditioner turbine ...152 6.2.6.3 Forced Cooling Air Temperature/ Flow Schedule. 152 Sample Test Provile ....... .............. 154 6.2.8 Profiles for Multi...Profiles for Reliability Demonstration Study Flow ....... . ....... 7 2 Typical MIL-STD-781 Profile ................ 23 3 Test Cycle A - Ambient Cooled
Indoor air quality in hairdressing salons in Taipei.
Chang, C-J; Cheng, S-F; Chang, P-T; Tsai, S-W
2018-01-01
To improve indoor air quality and to protect public health, Taiwan has enacted the "Indoor Air Quality Act (IAQ Act)" in 2012. For the general public, the indoor air quality in hair salons is important because it is a popular location that people will often visit for hair treatments. However, only a few exposure assessments regarding air pollutants have previously been performed in hair salons. To assess the air quality of hairdressing environments in Taipei, ten hairdressing salons were included for a walk-through survey in this study. In addition, the airborne concentrations of formaldehyde, volatile organic compounds (VOCs), CO 2 , and phthalate esters were also determined in 5 salons. Charcoal, XAD-2, and OVS-Tenax tubes were used for the air sampling, while the samples were analyzed with gas chromatography/mass spectrometer. It was found that the products used in hair salons contained various chemicals. In fact, from the walk-through survey, a total of 387 different ingredients were found on 129 hair product labels. The hair salons were not well ventilated, with CO 2 levels of 600 to 3576 ppm. The formaldehyde concentrations determined in this study ranged from 12.40 to 1.04 × 10 3 μg m -3 , and the maximum level was above the permissible exposure limit (PEL) of US Occupational Safety and Health Administration (US OSHA). Additionally, 83% of the samples were with levels higher than the standard regulated by Taiwan's IAQ Act. The concentrations of VOCs and phthalate esters were below the occupational exposure limits (OELs), but higher than what was found in general residential environments. The hair products were considered as the major source of air pollutants because significantly higher concentrations were found around the working areas. The number of perming treatments, the number of workers, and the frequency of using formaldehyde releasing products, were found to be associated with the levels of formaldehyde. This study indicates that efforts are needed to improve the indoor air quality in hairdressing salons in Taipei. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Ali, Usman; Syed, Jabir Hussain; Mahmood, Adeel; Li, Jun; Zhang, Gan; Jones, Kevin C; Malik, Riffat Naseem
2015-09-01
Levels of polychlorinated biphenyls (PCBs) were assessed in surface soils and passive air samples from the Indus River Basin, and the influential role of black carbon (BC) in the soil-air partitioning process was examined. ∑26-PCBs ranged between 0.002-3.03 pg m(-3) and 0.26-1.89 ng g(-1) for passive air and soil samples, respectively. Lower chlorinated (tri- and tetra-) PCBs were abundant in both air (83.9%) and soil (92.1%) samples. Soil-air partitioning of PCBs was investigated through octanol-air partition coefficients (KOA) and black carbon-air partition coefficients (KBC-A). The results of the paired-t test revealed that both models showed statistically significant agreement between measured and predicted model values for the PCB congeners. Ratios of fBCKBC-AδOCT/fOMKOA>5 explicitly suggested the influential role of black carbon in the retention and soil-air partitioning of PCBs. Lower chlorinated PCBs were strongly adsorbed and retained by black carbon during soil-air partitioning because of their dominance at the sampling sites and planarity effect. Copyright © 2015 Elsevier Ltd. All rights reserved.
This abstract is included for completeness of documentation, but this SOP was not used in the study.
The purpose of this SOP is to describe the procedures for analyzing both Stage II and Stage III soil and vacuum-cleaner collected house dust samples, and Stage III air samples u...
Zorn, Julia; Ritter, Bärbel; Miller, Manuel; Kraus, Monika; Northrup, Emily; Brielmeier, Markus
2017-06-01
One limitation to housing rodents in individually ventilated cages (IVCs) is the ineffectiveness of traditional health monitoring programs that test soiled bedding sentinels every quarter. Aerogen transmission does not occur with this method. Moreover, the transmission of numerous pathogens in bedding is uncertain, and sentinel susceptibility to various pathogens varies. A novel method using particle collection from samples of exhaust air was developed in this study which was also systematically compared with routine health monitoring using soiled bedding sentinels. We used our method to screen these samples for the presence of murine norovirus (MNV), a mouse pathogen highly prevalent in laboratory animal facilities. Exhaust air particles from prefilters of IVC racks with known MNV prevalence were tested by quantitative reverse transcription polymerase chain reaction (RT-qPCR). MNV was detected in exhaust air as early as one week with one MNV-positive cage per rack, while sentinels discharged MNV RNA without seroconverting. MNV was reliably and repeatedly detected in particles collected from samples of exhaust air in all seven of the three-month sampling rounds, with increasing MNV prevalence, while sentinels only seroconverted in one round. Under field conditions, routine soiled bedding sentinel health monitoring in our animal facility failed to identify 67% ( n = 85) of positive samples by RT-qPCR of exhaust air particles. Thus, this method proved to be highly sensitive and superior to soiled bedding sentinels in the reliable detection of MNV. These results represent a major breakthrough in hygiene monitoring of rodent IVC systems and contribute to the 3R principles by reducing the number of animals used and by improving experimental conditions.
Ceretti, Elisabetta; Feretti, Donatella; Viola, Gaia C V; Zerbini, Ilaria; Limina, Rosa M; Zani, Claudia; Capelli, Michela; Lamera, Rossella; Donato, Francesco; Gelatti, Umberto
2014-01-01
Air pollution has been recognized as a human carcinogen. Children living in urban areas are a high-risk group, because genetic damage occurring early in life is considered able to increase the risk of carcinogenesis in adulthood. This study aimed to investigate micronuclei (MN) frequency, as a biomarker of DNA damage, in exfoliated buccal cells of pre-school children living in a town with high levels of air pollution. A sample of healthy 3-6-year-old children living in Brescia, Northern Italy, was investigated. A sample of the children's buccal mucosa cells was collected during the winter months in 2012 and 2013. DNA damage was investigated using the MN test. Children's exposure to urban air pollution was evaluated by means of a questionnaire filled in by their parents that included items on various possible sources of indoor and outdoor pollution, and the concentration of fine particulate matter (PM10, PM2.5) and NO2 in the 1-3 weeks preceding biological sample collection. 181 children (mean age ± SD: 4.3 ± 0.9 years) were investigated. The mean ± SD MN frequency was 0.29 ± 0.13%. A weak, though statistically significant, association of MN with concentration of air pollutants (PM10, PM2.5 and NO2) was found, whereas no association was apparent between MN frequency and the indoor and outdoor exposure variables investigated via the questionnaire. This study showed a high MN frequency in children living in a town with heavy air pollution in winter, higher than usually found among children living in areas with low or medium-high levels of air pollution.
Brenner, David
2010-06-01
Most of the published empirical data on indoor air concentrations resulting from vapor intrusion of contaminants from underlying groundwater are for residential structures. The National Aeronautics and Space Administration (NASA) Research Park site, located in Moffett Field, CA, and comprised of 213 acres, is being planned for redevelopment as a collaborative research and educational campus with associated facilities. Groundwater contaminated with hydrocarbon and halogenated hydrocarbon volatile organic compounds (VOCs) is the primary environmental medium of concern at the site. Over a 15-month period, approximately 1000 indoor, outdoor ambient, and outdoor ambient background samples were collected from four buildings designated as historical landmarks using Summa canisters and analyzed by the U.S. Environmental Protection Agency TO-15 selective ion mode. Both 24-hr and sequential 8-hr samples were collected. Comparison of daily sampling results relative to daily background results indicates that the measured trichloroethylene (TCE) concentrations were primarily due to the subsurface vapor intrusion pathway, although there is likely some contribution due to infiltration of TCE from the outdoor ambient background concentrations. Analysis of the cis-1,2-dichloroethylene concentrations relative to TCE concentrations with respect to indoor air concentrations and the background air support this hypothesis; however, this indicates that relative contributions of the vapor intrusion and infiltration pathways vary with each building. Indoor TCE concentrations were also compared with indoor benzene and background benzene concentrations. These data indicate significant correlation between background benzene concentrations and the concentration of benzene in the indoor air, indicating benzene was present in the indoor air primarily through infiltration of outdoor air into the indoor space. By comparison, measured TCE indoor air concentrations showed a significantly different relationship to background concentrations. Analysis of the results show that indoor air samples can be used to definitively define the source of the TCE present in the indoor air space of large industrial buildings.
Pasquarella, Cesira; Veronesi, Licia; Napoli, Christian; Castiglia, Paolo; Liguori, Giorgio; Rizzetto, Rolando; Torre, Ida; Righi, Elena; Farruggia, Patrizia; Tesauro, Marina; Torregrossa, Maria V; Montagna, Maria T; Colucci, Maria E; Gallè, Francesca; Masia, Maria D; Strohmenger, Laura; Bergomi, Margherita; Tinteri, Carola; Panico, Manuela; Pennino, Francesca; Cannova, Lucia; Tanzi, Marialuisa
2012-03-15
A microbiological environmental investigation was carried out in ten dental clinics in Italy. Microbial contamination of water, air and surfaces was assessed in each clinic during the five working days, for one week per month, for a three-month period. Water and surfaces were sampled before and after clinical activity; air was sampled before, after, and during clinical activity. A wide variation was found in microbial environmental contamination, both within the participating clinics and for the different sampling times. Before clinical activity, microbial water contamination in tap water reached 51,200cfu/mL (colony forming units per milliliter), and that in Dental Unit Water Systems (DUWSs) reached 872,000cfu/mL. After clinical activity, there was a significant decrease in the Total Viable Count (TVC) in tap water and in DUWSs. Pseudomonas aeruginosa was found in 2.38% (7/294) of tap water samples and in 20.06% (59/294) of DUWS samples; Legionella spp. was found in 29.96% (89/297) of tap water samples and 15.82% (47/297) of DUWS samples, with no significant difference between pre- and post-clinical activity. Microbial air contamination was highest during dental treatments, and decreased significantly at the end of the working activity (p<0.05). The microbial buildup on surfaces increased significantly during the working hours. This study provides data for the establishment of standardized sampling methods, and threshold values for contamination monitoring in dentistry. Some very critical situations have been observed which require urgent intervention. Furthermore, the study emphasizes the need for research aimed at defining effective managing strategies for dental clinics. Copyright © 2012 Elsevier B.V. All rights reserved.
There are adverse health effects in populations living, working or going to school near major roadways. A study was designed to assess traffic emissions impacts on air quality and particle toxicity near a heavily-traveled highway. Several real-time and time-integrated sampling d...
Polycyclic aromatic hydrocarbons in a bakery indoor air: trends, dynamics, and dispersion.
Ielpo, Pierina; Taurino, Maria Rosaria; Buccolieri, Riccardo; Placentino, Claudia Marcella; Gallone, Francesco; Ancona, Valeria; Di Sabatino, Silvana
2018-02-27
Indoor air pollution assessment in work environments remains challenging due to a combination of logistic reasons and availability of costly instrumentation for data acquisition and post-processing. Existing literature focuses on energy production environments, hospitals, and less so on food production spaces. Studies on indoor air quality in bakeries are scarce or even absent. Motivated by this, the present study investigates indoor air quality in a bakery located in Bari province in South Italy, using a combination of approaches including analytical chemistry analyses and computational fluid dynamics to reconstruct the air ventilation in response to air temperature gradients within the working environment. PM 2.5 indoor samplings were collected every 6 h from 7 to 19 April 2013 in the proximity of two bakery ovens powered by gas and wood, respectively. For each sampling day, 4 PM 2.5 samples were collected: from 3:00 to 9:00 h (first), from 9:00 to 13:30 h (second), from 14:00 to 21:00 h (third), and from 21:00 to 3:00 h (fourth). In total, 40 samples were collected. On each sample, several polycyclic aromatic hydrocarbons (PAHs) were determined such as benzo[a]anthracene (228), benzo[b]fluoranthene (252), benzo[k]fluoranthene (252), benzo[a]pyrene (252), benzo[g,h,i]perylene (276), indeno[1,2,3-cd]pyrene (276), and dibenzo[a,h]anthracene (278), the main compounds of 16 priority US Environmental Protection Agency (US-EPA) PAHs in particulate phase. The PAH mean concentrations showed higher values during the first (from 3:00 to 9:00 h) and fourth (from 21:00 to 3:00 h) sampling intervals than the other two with benzo[a]pyrene mean values exceeding the Italian law limit of 1 ng/m 3 . Taking into account benzo[a]pyrene mean concentration for the first interval and the first plus the second one, which are the hours with the largest working activity, we have estimated that the baker and co-workers are exposed to a cancer risk of 4.3 × 10 -7 and 5.8 × 10 -7 , respectively (these values are lower than US-EPA recommended guideline of 10 -6 ). Our study was complemented by numerical analyses using state-of-the-art computational fluid dynamics to reconstruct at high resolution air movement from the various working places, i.e., the bakery and the selling area which were connected via a door. The numerical simulations were possible given that surface temperature using infrared thermography as well as air temperature was continuously recorded throughout the sampling acquisition. The use of this approach allowed us to estimate the transport and diffusion of benzo[a]pyrene from one area to the other thus complementing the point sampling information. Computational fluid dynamic simulation results confirm the presence of benzo[a]pyrene in the laboratory as obtained from the measurements and suggests its presence in the sales' area of the bakery with concentrations similar those found in the laboratory.
Size selective isocyanate aerosols personal air sampling using porous plastic foams
NASA Astrophysics Data System (ADS)
Khanh Huynh, Cong; Duc, Trinh Vu
2009-02-01
As part of a European project (SMT4-CT96-2137), various European institutions specialized in occupational hygiene (BGIA, HSL, IOM, INRS, IST, Ambiente e Lavoro) have established a program of scientific collaboration to develop one or more prototypes of European personal samplers for the collection of simultaneous three dust fractions: inhalable, thoracic and respirable. These samplers based on existing sampling heads (IOM, GSP and cassettes) use Polyurethane Plastic Foam (PUF) according to their porosity to support sampling and separator size of the particles. In this study, the authors present an original application of size selective personal air sampling using chemical impregnated PUF to perform isocyanate aerosols capturing and derivatizing in industrial spray-painting shops.
This SOP describes the procedures to set up, calibrate, initiate and terminate air sampling for persistent organic pollutants. This method is used to sample air, indoors and outdoors, at homes and at day care centers over a 48-hr period.
Effect of Air and Vacuum Storage on the Tensile Properties of X-Ray Exposed Aluminized-FEP
NASA Technical Reports Server (NTRS)
deGroh, Kim K.; Gummow, Jonathan D.
2000-01-01
Metallized Teflon(Registered Trademark) FEP (fluorinated ethylene propylene), a common spacecraft thermal control material, from the exterior layer of the Hubble Space Telescope (HST) has become embrittled and suffers from extensive cracking. Teflon samples retrieved during Hubble servicing missions and from the Long Duration Exposure Facility (LDEF) indicate that there may be continued degradation in tensile properties over time. An investigation has been conducted to evaluate the effect of air and vacuum storage on the mechanical properties of x-ray exposed FEP. Aluminized-FEP (Al-FEP) tensile samples were irradiated with 15.3 kV Cu x-rays and stored in air or under vacuum for various time periods. Tensile data indicate that samples stored in air display larger decreases in tensile properties than for samples stored under vacuum. Air-stored samples developed a hazy appearance, which corresponded to a roughening of the aluminized surface. Optical property changes were also characterized. These findings indicate that air exposure plays a role in the degradation of irradiated FEP, therefore proper sample handling and storage is necessary with materials retrieved from space.
[Bacteriological quality of air in a ward for sterile pharmaceutical preparations].
Caorsi P, Beatriz; Sakurada Z, Andrea; Ulloa F, M Teresa; Pezzani V, Marcela; Latorre O, Paz
2011-02-01
An extremely clean area is required for preparation of sterile pharmaceutical compounds, in compliance with international standards, to minimize the probability of microbial contamination. To evaluate the bacteriological quality of the air in the Sterile Pharmaceutical Preparation Unit of the University of Chile's Clinical Hospital and to set up alerts and action levels of bacterial growth. We studied eight representative sites of our Unit on a daily basis from January to February 2005 and twice a week from June 2005 to February 2006. We collected 839 samples of air by impact in the Petri dish. 474 (56.5%) samples were positive; 17 (3.5%) of them had an inappropriate bacterial growth (2% of total samples). The samples from sites 1 and 2 (big and small biosafety cabinets) were negative. The countertop and transfer area occasionally exceeded the bacterial growth limits. The most frequently isolated bacteria were coagulase-negative staphylococci, Micrococcus spp and Corynebacterium spp, from skin microbiota, and Bacillus spp, an environmental bacteria. From a microbiological perspective, the air quality in our sterile preparation unit complied with international standards. Setting institutional alerts and action levels and appropriately identifying bacteria in sensitive areas permits quantification of the microbial load and application of preventive measures.
Potential genotoxic effects of melted snow from an urban area revealed by the Allium cepa test.
Blagojević, Jelena; Stamenković, Gorana; Vujosević, Mladen
2009-09-01
The presence of well-known atmospheric pollutants is regularly screened for in large towns but knowledge about the effects of mixtures of different pollutants and especially their genotoxic potential is largely missing. Since falling snow collects pollutants from the air, melted snow samples could be suitable for evaluating potential genotoxicity. For this purpose the Allium cepa anaphase-telophase test was used to analyse melted snow samples from Belgrade, the capital city of Serbia. Samples of snow were taken at two sites, characterized by differences in pollution intensity, in three successive years. At the more polluted site the analyses showed a very high degree of both toxicity and genotoxicity in the first year of the study corresponding to the effects of the known mutagen used as the positive control. At the other site the situation was much better but not without warning signals. The results showed that standard analyses for the presence of certain contaminants in the air do not give an accurate picture of the possible consequences of urban air pollution because the genotoxic potential remains hidden. The A. cepa test has been demonstrated to be very convenient for evaluation of air pollution through analyses of melted snow samples.
Hydrogen leak detection in the Space Shuttle
NASA Technical Reports Server (NTRS)
Barile, Ronald G
1992-01-01
This study focuses on a helium gas jet flowing into room air. Measurements of helium concentration and velocity in the jet-air mixture are reported. The objective is to learn about jet characteristics so that dynamically similar hydrogen leaks may be located in the Space Shuttle. The hazardous gas detection system (HGDS) in the mobile launch pad uses mass spectrometers to monitor the shuttle environment for leaks. The mass spectrometers are fed by long sample tubes which draw gas from the payload bay, mid body, aft engine compartment and external tank. The overall purpose of this study is to improve the HGDS especially in its potential for locating hydrogen leaks. A rapid-response leak detection experiment was designed, built, and tested, following on the work done in this program last summer. The apparatus included a Perkin Elmer MGA-1200 mass spectrometer and air velocity transducer, both monitored by a Macintosh IIFX computer using LabVIEW software. A jet of helium flowing into the lab air simulated a gas leak. Steady helium or hydrogen-nitrogen jets were logged for concentration and velocity, and the power spectral density of each was computed. Last year, large eddies and vortices were visually seen with Schlieren imaging, and they were detected in the time plots of the various instruments. The response time of the MGA-1200 was found in the range of 0.05 to 0.1 sec. Pulsed concentration waves were clearly detected at 25 cycles per sec by spectral analysis of MGA data. No peaks were detected in the power spectrum, so in the present study, 10 Hz bandwidth-averaged power levels were examined at regular frequency intervals. The practical consequences of last year's study are as follows: sampling frequency should be increased above the present rate of 1 sample per second so that transients could be observed and analyzed with frequency response methods. Many more experiments and conditions were observed in this second summer, including the effects of orifice diameter, jet velocity, sample tube design, radial effects, vertical flow, and low hydrogen concentrations (1 percent). A frequent observation was that the power spectrum, calculated from the Fourier transform of concentration fluctuations, gives a separate piece of information from concentration. Many of the tests suggest that power is high where mixing occurs at the helium-air interface. This fact is apparently independent of the concentration level, which could be high or low, but depends on the sample location relative to the jet (leak) origin, whereas high concentration may be due to a strong leak far away or a small leak close to the sample tube. If the power is low for any concentration level, this would signify helium is arriving at the sample tube by diffusion, not chaotic mixing caused by the jet interaction with air. The practical result is to propose a modification of the HGDL mass spectrometer data sampling and software so that sampling rates could be capable of observing at least 25 Hz fluctuations.
Unanticipated potential cancer risk near metal recycling facilities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Raun, Loren, E-mail: raun@rice.edu; Pepple, Karl, E-mail: pepple.karl@epa.gov; Hoyt, Daniel, E-mail: hoyt.daniel@epa.gov
2013-07-15
Metal recycling is an important growing industry. Prior to this study, area sources consisting of metal recycling facilities fell in a category of limited regulatory scrutiny because of assumed low levels of annual emissions. Initiating with community complaints of nuisance from smoke, dust and odor, the Houston Department of Health and Human Services (HDHHS) began a monitoring program outside metal recycler facilities and found metal particulates in outdoor ambient air at levels which could pose a carcinogenic human health risk. In a study of five similar metal recycler facilities which used a torch cutting process, air downwind and outside themore » facility was sampled for eight hours between 6 and 10 times each over 18 months using a mobile laboratory. Ten background locations were also sampled. Iron, manganese, copper, chromium, nickel, lead, cobalt, cadmium and mercury were detected downwind of the metal recyclers at frequencies ranging from 100% of the time for iron to 2% of the time for mercury. Of these metals, chromium, nickel, lead, cobalt, cadmium and mercury were not detected in any sample in the background. Two pairs of samples were analyzed for total chromium and hexavalent chromium to establish a ratio of the fraction of hexavalent chromium in total chromium. This fraction was used to estimate hexavalent chromium at all locations. The carcinogenic risk posed to a residential receptor from metal particulate matter concentrations in the ambient air attributed to the metal recyclers was estimated from each of the five facilities in an effort to rank the importance of this source and inform the need for further investigation. The total risk from these area sources ranged from an increased cancer risk of 1 in 1,000,000 to 6 in 10,000 using the 95th upper confidence limit of the mean of the carcinogenic metal particulate matter concentration, assuming the point of the exposure is the sample location for a residential receptor after accounting for wind direction and the number of shifts that could operate a year. Further study is warranted to better understand the metal air pollution levels in the community and if necessary, to evaluate the feasibility of emission controls and identify operational improvements and best management practices for this industry. This research adds two new aspects to the literature: identification of types and magnitude of metal particulate matter air pollutants associated with a previously unrecognized area source, metal recyclers and their potential risk to health. -- Highlights: • Air monitoring study in response to community complaints found metal contamination. • Metal recyclers found to potentially pose cancer from metal particulates • Chromium, nickel, cobalt and cadmium samples were detected in five metal recyclers. • These metals were not detected in background air samples. • Estimated increased cancer risk ranges from 1 in 1,000,000 to 8 in 10,000.« less
COMMUNITY STRESSORS AND SUSCEPTIBILITY TO AIR POLLUTION IN URBAN ASTHMA
Given our large sample size within and across communities, our unique data on year-round fine-scale variability in multiple air pollutants, and our strong experience in community –based environmental health education and outreach, we believe that our study will provid...
EVALUATION OF MEDIA FOR RECOVERY OF AEROSOLIZED BACTERIA
Disease transmission by airborne bacteria is well known.Bacterial burden in indoor air is estimated by sampling the air and estimating Colony Forming Unites (CFU) using a variety of media.In this study, the recovery of bacteria, after aerosolization in an aerosol chamber, and emp...
FORMAL UNCERTAINTY ANALYSIS OF A LAGRANGIAN PHOTOCHEMICAL AIR POLLUTION MODEL. (R824792)
This study applied Monte Carlo analysis with Latin
hypercube sampling to evaluate the effects of uncertainty
in air parcel trajectory paths, emissions, rate constants,
deposition affinities, mixing heights, and atmospheric stability
on predictions from a vertically...
U.S.-MEXICO BORDER PROGRAM ARIZONA BORDER STUDY--QA ANALYTICAL RESULTS FOR METALS IN BLANK SAMPLES
The Metals in Blank Samples data set contains the analytical results of measurements of up to 27 metals in 52 blank samples. Measurements were made in blank samples of dust, indoor air, food, water, and dermal wipe residue. Blank samples were used to assess the potential for sa...
Getachew, Hailu; Derbie, Awoke; Mekonnen, Daniel
2018-01-01
The hospital environment is a source of medically important pathogens that are mostly multidrug resistant (MDR) and posing a major therapeutic challenge. The aim of this study was to assess the surface and air bacteriology of selected wards at Felege Hiwot Referral Hospital (FHRH), Northwest Ethiopia. A cross-sectional study was carried out from 15th February to 30th April 2017. A total of 356 surface and air samples were collected from selected wards using 5% sheep blood agar (Oxoid, UK) and processed at FHRH microbiology laboratory following the standard bacteriological procedures. Pure isolates were tested against the recommended antibiotics using Kirby-Bauer disc diffusion methods, and the susceptibility profile was determined based on Clinical Laboratory Standards Institute (CLSI). Data were entered and analyzed using SPSS version 23 for Windows. Of the total 356 samples processed, 274 were from surfaces and 82 were from air. Among these, 141 (39.6%) showed bacterial growth, yielding a total of 190 isolates. Gram-positive isolates were predominant at 81.6% ( n =155), while the gram negatives were at 18.4% ( n =35). The main isolates were coagulase negative staphylococci ( CoNs ), 44%, followed by S. aureus , 37.4%, and Klebsiella species at 11.6%. The bacterial load on surfaces and air was found beyond the standard limits. Besides, the antimicrobial susceptibility profile of the isolates showed that about 75% of the identified isolates were found resistant for two and more antimicrobial agents tested. This study showed high degree of bacterial load that is beyond the standard limits on both surfaces and air samples of the hospital. Furthermore, some 75% of the isolates were found multidrug resistant. Therefore, it is important to evaluate and strengthen the infection prevention practice of the hospital. Moreover, stakeholders should also reinforce actions to decrease the pressure of antimicrobial resistance in the studied area.
Wheeler, Amanda J; Xu, Xiaohong; Kulka, Ryan; You, Hongyu; Wallace, Lance; Mallach, Gary; Van Ryswyk, Keith; MacNeill, Morgan; Kearney, Jill; Rasmussen, Pat E; Dabek-Zlotorzynska, Ewa; Wang, Daniel; Poon, Raymond; Williams, Ron; Stocco, Corinne; Anastassopoulos, Angelos; Miller, J David; Dales, Robert; Brook, Jeffrey R
2011-03-01
The Windsor, Ontario Exposure Assessment Study evaluated the contribution of ambient air pollutants to personal and indoor exposures of adults and asthmatic children living in Windsor, Ontario, Canada. In addition, the role of personal, indoor, and outdoor air pollution exposures upon asthmatic children's respiratory health was assessed. Several active and passive sampling methods were applied, or adapted, for personal, indoor, and outdoor residential monitoring of nitrogen dioxide, volatile organic compounds, particulate matter (PM; PM-2.5 pm [PM2.5] and < or =10 microm [PM10] in aerodynamic diameter), elemental carbon, ultrafine particles, ozone, air exchange rates, allergens in settled dust, and particulate-associated metals. Participants completed five consecutive days of monitoring during the winter and summer of 2005 and 2006. During 2006, in addition to undertaking the air pollution measurements, asthmatic children completed respiratory health measurements (including peak flow meter tests and exhaled breath condensate) and tracked respiratory symptoms in a diary. Extensive quality assurance and quality control steps were implemented, including the collocation of instruments at the National Air Pollution Surveillance site operated by Environment Canada and at the Michigan Department of Environmental Quality site in Allen Park, Detroit, MI. During field sampling, duplicate and blank samples were also completed and these data are reported. In total, 50 adults and 51 asthmatic children were recruited to participate, resulting in 922 participant days of data. When comparing the methods used in the study with standard reference methods, field blanks were low and bias was acceptable, with most methods being within 20% of reference methods. Duplicates were typically within less than 10% of each other, indicating that study results can be used with confidence. This paper covers study design, recruitment, methodology, time activity diary, surveys, and quality assurance and control results for the different methods used.
Cariou, Stephane; Guillot, Jean-Michel
2006-01-01
Tedlar bags, which are widely used to collect air samples, especially VOCs and odorous atmospheres, can allow humidity to diffuse when relative humidity levels differ between the inside and outside. Starting with dry air inside the bag and humid air outside, we monitored equilibrium times under several conditions showing the evolution and influence of collected volumes and exposed surfaces. A double-film Tedlar bag was made, to limit the impact of external humidity on a sample at low humidity level. With the addition of a drying agent between both films, the evolution of humidity of a sample can be stopped for several hours. When a VOC mixture was monitored in a humid atmosphere, humidity was decreased but no significant evolution of VOC concentrations was observed.
Mendez, Gregory O.; Majewski, Michael S.; Foreman, William T.; Morita, Andrew Y.
2015-01-01
Sampling results show concentrations of the gasoline oxygenate methyl tert-butyl ether in water and air samples declined after it was phased out by the State of California in January 2004. The largest concentrations of gasoline hydrocarbons benzene and toluene in water were detected at or near the surface of the SWR. Isophorone and phenol were the two most frequently detected BNA compounds in water. Diuron, prometon, and simazine were the most frequently detected pesticide compounds in water. Concentrations of benzene and toluene in air samples were highest during the cooler months and had a consistent seasonal pattern over time. Ten PAH compounds were detected frequently in air samples. Twelve pesticide compounds were also detected in air samples. Surficial bed-sediment samples were analyzed for 53 PAHs; 22 of the compounds had one or more detections. Surficial bed-sediment samples were analyzed for 22 organic compounds; only 6 compounds had one or more detections. Surficial bed-sediment samples were analyzed for 37 metals.
Passive air sampling theory for semivolatile organic compounds.
Bartkow, Michael E; Booij, Kees; Kennedy, Karen E; Müller, Jochen F; Hawker, Darryl W
2005-07-01
The mathematical modelling underlying passive air sampling theory can be based on mass transfer coefficients or rate constants. Generally, these models have not been inter-related. Starting with basic models, the exchange of chemicals between the gaseous phase and the sampler is developed using mass transfer coefficients and rate constants. Importantly, the inter-relationships between the approaches are demonstrated by relating uptake rate constants and loss rate constants to mass transfer coefficients when either sampler-side or air-side resistance is dominating chemical exchange. The influence of sampler area and sampler volume on chemical exchange is discussed in general terms and as they relate to frequently used parameters such as sampling rates and time to equilibrium. Where air-side or sampler-side resistance dominates, an increase in the surface area of the sampler will increase sampling rates. Sampling rates are not related to the sampler/air partition coefficient (K(SV)) when air-side resistance dominates and increase with K(SV) when sampler-side resistance dominates.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Levin, J.O.; Andersson, K.; Lindahl, R.
1985-05-01
Formaldehyde is sampled from air with the use of a standard miniature glass fiber filter impregnated with 2,4-dinitrophenylhydrazine and phosphoric acid. The formaldehyde hydrazone is desorbed from the filter with acetonitrile and determined by high-performance liquid chromatography using UV detection at 365 nm. Recovery of gas-phase-generated formaldehyde as hydrazone from a 13-mm impregnated filter is 80-100% in the range 0.3-30 ..mu..g of formaldehyde. This corresponds to 0.1-10 mg/m/sup 3/ in a 3-L air sample. When the filter sampling system is used in the active mode, air can be sampled at a rate of up to 1 L/min, affording an overallmore » sensitivity of about 1 ..mu..g/m/sup 3/ based on a 60-L air sample. Results are given from measurements of formaldehyde in indoor air. The DNP-coated filters were also evaluated for passive sampling. In this case 37-mm standard glass fibers were used and the sampling rate was 55-65 mL/min in two types of dosimeters. The diffusion samplers are especially useful for personal exposure monitoring in the work environment. 24 references, 2 figures, 4 tables.« less
The atmosphere can be a source of certain water soluble volatile organic compounds in urban streams
Kenner, Scott J.; Bender, David A.; Zogorski, John S.; ,; James F. Pankow,
2014-01-01
Surface water and air volatile organic compound (VOC) data from 10 U.S. Geological Survey monitoring sites were used to evaluate the potential for direct transport of VOCs from the atmosphere to urban streams. Analytical results of 87 VOC compounds were screened by evaluating the occurrence and detection levels in both water and air, and equilibrium concentrations in water (Cws) based on the measured air concentrations. Four compounds (acetone, methyl tertiary butyl ether, toluene, and m- & p-xylene) were detected in more than 20% of water samples, in more than 10% of air samples, and more than 10% of detections in air were greater than long-term method detection levels (LTMDL) in water. Benzene was detected in more than 20% of water samples and in more than 10% of air samples. Two percent of benzene detections in air were greater than one-half the LTMDL in water. Six compounds (chloroform, p-isopropyltoluene, methylene chloride, perchloroethene, 1,1,1-trichloroethane, and trichloroethene) were detected in more than 20% of water samples and in more than 10% of air samples. Five VOCs, toluene, m- & p-xylene, methyl tert-butyl ether (MTBE), acetone, and benzene were identified as having sufficiently high concentrations in the atmosphere to be a source to urban streams. MTBE, acetone, and benzene exhibited behavior that was consistent with equilibrium concentrations in the atmosphere.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Flaherty, Julia E.; Glissmeyer, John A.
2015-03-18
Tests were performed to evaluate a sample conditioning unit for stack monitoring at Hanford Tank Waste Treatment and Immobilization Plant (WTP) exhaust stacks with elevated air temperatures. The LV-S2, LV-S3, HV-S3A and HV-S3B exhaust stacks are expected to have elevated air temperature and dew point. At these emission points, exhaust temperatures are too high to deliver the air sample directly to the required stack monitoring equipment. As a result, a sample conditioning system is considered to cool and dry the air prior to its delivery to the stack monitoring system. The method proposed for the sample conditioning is a dilutionmore » system that will introduce cooler, dry air to the air sample stream. This method of sample conditioning is meant to reduce the sample temperature while avoiding condensation of moisture in the sample stream. An additional constraint is that the ANSI/HPS N13.1-1999 standard states that at least 50% of the 10 μm aerodynamic diameter (AD) particles present in the stack free stream must be delivered to the sample collector. In other words, depositional loss of particles should be limited to 50% in the sampling, transport, and conditioning systems. Based on estimates of particle penetration through the LV-S3 sampling system, the diluter should perform with about 80% penetration or better to ensure that the total sampling system passes the 50% or greater penetration criterion.« less
NASA Astrophysics Data System (ADS)
Brent, L. C.; He, H.; Arkinson, H. L.; Stehr, J. W.; Ring, A.; Marufu, L.; Reiner, J.; Sander, L. C.; Dickerson, R. R.
2014-12-01
Routine, light aircraft air-monitoring conducted in MD provides insight into atmospheric photochemical processing as a function of altitude in the boundary layer and lower free troposphere. We present correlations between the optical properties and chemical composition of aerosols at ~1 km altitude over Maryland. Data were collected during the peak smog day and a dissipation day during an air quality episode studied in DISCOVER-AQ, July 2011. Post flight filter sample analysis shows a positive trend between measurable carboxylate concentrations and particle size with a recirculating, aged, urban air mass influenced with southeasterly marine winds (peak day). A westerly influx of air from the Ohio River Valley on the dissipation day was depleted in carboxylates compared with samples collected over the same location two days prior. These samples contained quantifiable concentrations of cis-pinonic acid, a reaction product of pinene after ozonation and photochemical oxidation. New techniques were developed to improve airborne data collection and analysis of water soluble organic acids (WSOA), a frequently dominant fraction of particulate matter (PM). An ion chromatographic mass spectrometric method was developed using NIST Standard Referencing Material 1649b, Urban Dust, as a surrogate material to achieve separation and resolution of at least 34 organic acids. Analysis of aircraft filter samples resulted in detection of 16 organic acids of which 12 were quantified. Eight inorganic species were also quantified. Aged, re-circulated metropolitan air showed a greater number of dicarboxylic acids than new transport air from the west and may provide a useful test of SOA formation theory.
Bergh, Caroline; Magnus Åberg, K; Svartengren, Magnus; Emenius, Gunnel; Östman, Conny
2011-07-01
An extensive study has been conducted on the prevalence of organophosphorous flame retardants/plasticizers and phthalate ester plasticizers in indoor air. The targeted substances were measured in 45 multi-storey apartment buildings in Stockholm, Sweden. The apartment buildings were classified as high or low risk with regard to the reporting of sick building symptoms (SBS) within the project Healthy Sustainable Houses in Stockholm (3H). Air samples were taken from two to four apartments per building (in total 169 apartments) to facilitate comparison within and between buildings. Association with building characteristics has been examined as well as association with specific sources by combining chemical analysis and exploratory uni- and multivariate data analysis. The study contributes to the overall perspective of levels of organophosphate and phthalate ester in indoor air enabling comparison with other studies. The results indicated little or no difference in the concentrations of the target substances between the two risk classifications of the buildings. The differences between the apartments sampled within (intra) buildings were greater than the differences between (inter) buildings. The concentrations measured in air ranged up to 1200 ng m(-3) for organophosphate esters and up to 11 000 ng m(-3) for phthalate esters. Results in terms of sources were discerned e.g. PVC flooring is a major source of benzylbutyl phthalate in indoor air.
Chang, Feng-Chih; Simcik, M.F.; Capel, P.D.
2011-01-01
This is the first report on the ambient levels of glyphosate, the most widely used herbicide in the United States, and its major degradation product, aminomethylphosphonic acid (AMPA), in air and rain. Concurrent, weekly integrated air particle and rain samples were collected during two growing seasons in agricultural areas in Mississippi and Iowa. Rain was also collected in Indiana in a preliminary phase of the study. The frequency of glyphosate detection ranged from 60 to 100% in both air and rain. The concentrations of glyphosate ranged from 3 and from <0.1 to 2.5 µg/L in air and rain samples, respectively. The frequency of detection and median and maximum concentrations of glyphosate in air were similar or greater to those of the other high-use herbicides observed in the Mississippi River basin, whereas its concentration in rain was greater than the other herbicides. It is not known what percentage of the applied glyphosate is introduced into the air, but it was estimated that up to 0.7% of application is removed from the air in rainfall. Glyphosate is efficiently removed from the air; it is estimated that an average of 97% of the glyphosate in the air is removed by a weekly rainfall ≥30 mm.
Rich, Alisa; Grover, James P; Sattler, Melanie L
2014-01-01
Information regarding air emissions from shale gas extraction and production is critically important given production is occurring in highly urbanized areas across the United States. Objectives of this exploratory study were to collect ambient air samples in residential areas within 61 m (200 feet) of shale gas extraction/production and determine whether a "fingerprint" of chemicals can be associated with shale gas activity. Statistical analyses correlating fingerprint chemicals with methane, equipment, and processes of extraction/production were performed. Ambient air sampling in residential areas of shale gas extraction and production was conducted at six counties in the Dallas/Fort Worth (DFW) Metroplex from 2008 to 2010. The 39 locations tested were identified by clients that requested monitoring. Seven sites were sampled on 2 days (typically months later in another season), and two sites were sampled on 3 days, resulting in 50 sets of monitoring data. Twenty-four-hour passive samples were collected using summa canisters. Gas chromatography/mass spectrometer analysis was used to identify organic compounds present. Methane was present in concentrations above laboratory detection limits in 49 out of 50 sampling data sets. Most of the areas investigated had atmospheric methane concentrations considerably higher than reported urban background concentrations (1.8-2.0 ppm(v)). Other chemical constituents were found to be correlated with presence of methane. A principal components analysis (PCA) identified multivariate patterns of concentrations that potentially constitute signatures of emissions from different phases of operation at natural gas sites. The first factor identified through the PCA proved most informative. Extreme negative values were strongly and statistically associated with the presence of compressors at sample sites. The seven chemicals strongly associated with this factor (o-xylene, ethylbenzene, 1,2,4-trimethylbenzene, m- and p-xylene, 1,3,5-trimethylbenzene, toluene, and benzene) thus constitute a potential fingerprint of emissions associated with compression. Information regarding air emissions from shale gas development and production is critically important given production is now occurring in highly urbanized areas across the United States. Methane, the primary shale gas constituent, contributes substantially to climate change; other natural gas constituents are known to have adverse health effects. This study goes beyond previous Barnett Shale field studies by encompassing a wider variety of production equipment (wells, tanks, compressors, and separators) and a wider geographical region. The principal components analysis, unique to this study, provides valuable information regarding the ability to anticipate associated shale gas chemical constituents.
Correction of Anisokinetic Sampling Errors.
ERIC Educational Resources Information Center
Nelson, William G.
Gas flow patterns at a sampling nozzle are described in this presentation for the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971. Three situations for sampling velocity are illustrated and analyzed, where the flow upstream of a sampling probe is: (1) equal to free stream…
NHEXAS PHASE I REGION 5 STUDY--QA ANALYTICAL RESULTS FOR METALS IN BLANKS
This data set includes analytical results for measurements of metals in 205 blank samples and for particles in 64 blank samples. Measurements were made for up to 12 metals in blank samples of air, dust, soil, water, food and beverages, blood, hair, and urine. Blank samples were u...
Fungal monitoring of the indoor air of the Museo de La Plata Herbarium, Argentina.
Mallo, Andrea C; Elíades, Lorena A; Nitiu, Daniela S; Saparrat, Mario C N
Biological agents, such as fungal spores in the air in places where scientific collections are stored, can attack and deteriorate them. The aim of this study was to gather information on the indoor air quality of the Herbarium of Vascular Plants of the Museo de Ciencias Naturales de La Plata, Argentina, in relation to fungal propagules and inert particles. This study was made using a volumetric system and two complementary sampling methods: (1) a non-viable method for direct evaluation, and (2) a viable method by culture for viable fungal propagules. The non-viable method led to ten spore morphotypes being found from related fungal sources. A total of 4401.88spores/m 3 and 32135.18 inert suspended particles/m 3 were recorded. The viable method led to the finding of nine fungal taxa as viable spores that mostly belonged to anamorphic forms of Ascomycota, although the pigmented yeast Rhodotorula F.C. Harrison (Basidiomycota) was also found. A total count of 40,500fungal CFU/m 3 air was estimated for all the sites sampled. Both the non-viable and viable sampling methods were necessary to monitor the bio-aerosol load in the La Plata Herbarium. The indoor air of this institution seems to be reasonably adequate for the conservation of vascular plants due to the low indoor/outdoor index, low concentrations of air spores, and/or lack of indicators of moisture problems. Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.
Detection and quantification of reactive oxygen species (ROS) in indoor air.
Montesinos, V Nahuel; Sleiman, Mohamad; Cohn, Sebastian; Litter, Marta I; Destaillats, Hugo
2015-06-01
Reactive oxygen species (ROS), such as free radicals and peroxides, are environmental trace pollutants potentially associated with asthma and airways inflammation. These compounds are often not detected in indoor air due to sampling and analytical limitations. This study developed and validated an experimental method to sample, identify and quantify ROS in indoor air using fluorescent probes. Tests were carried out simultaneously using three different probes: 2',7'-dichlorofluorescin (DCFH) to detect a broad range of ROS, Amplex ultra Red® (AuR) to detect peroxides, and terephthalic acid (TPA) to detect hydroxyl radicals (HO(•)). For each test, air samples were collected using two impingers in series kept in an ice bath, containing each 10 mL of 50 mM phosphate buffer at pH 7.2. In tests with TPA, that probe was also added to the buffer prior to sampling; in the other two tests, probes and additional reactants were added immediately after sampling. The concentration of fluorescent byproducts was determined fluorometrically. Calibration curves were developed by reacting DCFH and AuR with known amounts of H2O2, and using known amounts of 2-hydroxyterephthalic acid (HTPA) for TPA. Low detection limits (9-13 nM) and quantification limits (18-22 nM) were determined for all three probes, which presented a linear response in the range 10-500 nM for AuR and TPA, and 100-2000 nM for DCFH. High collection efficiency (CE) and recovery efficiency (RE) were observed for DCFH (CE=RE=100%) and AuR (CE=100%; RE=73%) by sampling from a laboratory-developed gas phase H2O2 generator. Interference of co-occurring ozone was evaluated and quantified for the three probes by sampling from the outlet of an ozone generator. The method was demonstrated by sampling air emitted by two portable air cleaners: a strong ozone generator (AC1) and a plasma generator (AC2). High ozone levels emitted by AC1 did not allow for simultaneous determination of ROS levels due to high background levels associated with ozone decomposition in the buffer. However, emitted ROS were quantified at the outlet of AC2 using two of the three probes. With AuR, the concentration of peroxides in air emitted by the air cleaner was 300 ppt of H2O2 equivalents. With TPA, the HO(•) concentration was 47 ppt. This method is best suited to quantify ROS in the presence of low ozone levels. Published by Elsevier B.V.
A UAV-based active AirCore system for measurements of greenhouse gases
NASA Astrophysics Data System (ADS)
Andersen, Truls; Scheeren, Bert; Peters, Wouter; Chen, Huilin
2018-05-01
We developed and field-tested an unmanned aerial vehicle (UAV)-based active AirCore for atmospheric mole fraction measurements of CO2, CH4, and CO. The system applies an alternative way of using the AirCore technique invented by NOAA. As opposed to the conventional concept of passively sampling air using the atmospheric pressure gradient during descent, the active AirCore collects atmospheric air samples using a pump to pull the air through the tube during flight, which opens up the possibility to spatially sample atmospheric air. The active AirCore system used for this study weighs ˜ 1.1 kg. It consists of a ˜ 50 m long stainless-steel tube, a small stainless-steel tube filled with magnesium perchlorate, a KNF micropump, and a 45 µm orifice working together to form a critical flow of dried atmospheric air through the active AirCore. A cavity ring-down spectrometer (CRDS) was used to analyze the air samples on site not more than 7 min after landing for mole fraction measurements of CO2, CH4, and CO. We flew the active AirCore system on a UAV near the atmospheric measurement station at Lutjewad, located in the northwest of the city of Groningen in the Netherlands. Five consecutive flights took place over a 5 h period on the same morning, from sunrise until noon. We validated the measurements of CO2 and CH4 from the active AirCore against those from the Lutjewad station at 60 m. The results show a good agreement between the measurements from the active AirCore and the atmospheric station (N = 146; R2CO2: 0.97 and R2CH4: 0.94; and mean differences: ΔCO2: 0.18 ppm and ΔCH4: 5.13 ppb). The vertical and horizontal resolution (for CH4) at typical UAV speeds of 1.5 and 2.5 m s-1 were determined to be ±24.7 to 29.3 and ±41.2 to 48.9 m, respectively, depending on the storage time. The collapse of the nocturnal boundary layer and the buildup of the mixed layer were clearly observed with three consecutive vertical profile measurements in the early morning hours. Besides this, we furthermore detected a CH4 hotspot in the coastal wetlands from a horizontal flight north to the dike, which demonstrates the potential of this new active AirCore method to measure at locations where other techniques have no practical access.
Systematic Evaluation of Aggressive Air Sampling for Bacillus ...
Report The primary objectives of this project were to evaluate the Aggressive Air Sampling (AAS) method compared to currently used surface sampling methods and to determine if AAS is a viable option for sampling Bacillus anthracis spores.
[Hygienic evaluation of the total mutagenic activity of snow samples from Magnitogorsk].
Legostaeva, T B; Ingel', F I; Antipanova, N A; Iurchenko, V V; Iuretseva, N A; Kotliar, N N
2010-01-01
The paper gives the results of 4-year monitoring of the total mutagenic activity of snow samples from different Magnitogork areas in a test for induction of dominant lethal mutations (DLM) in the gametes of Drosophila melanogaster. An association was first found between the rate of DLM and the content of some chemical compounds in the ambient air and snow samples; moreover all the substances present in the samples, which had found genotoxic effects, showed a positive correlation with the rate of DLM. Furthermore, direct correlations were first established between the rate of DLM and the air pollution index and morbidity rates in 5-7-year-old children residing in the areas under study. The findings allow the test for induction of dominant lethal mutations (DLM) in the gametes of Drosophila melanogaster to be recommended due to its unique informative and prognostic value for monitoring ambient air pollution and for extensive use in the risk assessment system.
Fabrication of a printed capacitive air-gap touch sensor
NASA Astrophysics Data System (ADS)
Lee, Sang Hoon; Seo, Hwiwon; Lee, Sangyoon
2018-05-01
Unlike lithography-based processes, printed electronics does not require etching, which makes it difficult to fabricate electronic devices with an air gap. In this study, we propose a method to fabricate capacitive air-gap touch sensors via printing and coating. First, the bottom electrode was fabricated on a flexible poly(ethylene terephthalate) (PET) substrate using roll-to-roll gravure printing with silver ink. Then poly(dimethylsiloxane) (PDMS) was spin coated to form a sacrificial layer. The top electrode was fabricated on the sacrificial layer by spin coating with a stretchable silver ink. The sensor samples were then put in a tetrabutylammonium (TBAF) bath to generate the air gap by removing the sacrificial layer. The capacitance of the samples was measured for verification, and the results show that the capacitance increases in proportion to the applied force from 0 to 2.5 N.
Convair F-106B Delta Dart with Air Sampling Equipment
1974-04-21
The National Aeronautics and Space Administration (NASA) Lewis Research Center’s Convair F-106B Delta Dart equipped with air sampling equipment in the mid-1970s. NASA Lewis created and managed the Global Air Sampling Program (GASP) in 1972 in partnership with several airline companies. NASA researchers used the airliners’ Boeing 747 aircraft to gather air samples to determine the amount of pollution present in the stratosphere. Private companies developed the air sampling equipment for the GASP program, and Lewis created a particle collector. The collector was flight tested on NASA Lewis’ F-106B in the summer of 1973. The sampling equipment was automatically operated once the proper altitude was achieved. The sampling instruments collected dust particles in the air so their chemical composition could be analyzed. The equipment analyzed one second’s worth of data at a time. The researchers also monitored carbon monoxide, monozide, ozone, and water vapor. The 747 flights began in December 1974 and soon included four airlines flying routes all over the globe. The F-106B augmented the airline data with sampling of its own, seen here. It gathered samples throughout this period from locations such as New Mexico, Texas, Michigan, and Ohio. In July 1977 the F-106B flew eight GASP flights in nine days over Alaska to supplement the earlier data gathered by the airlines.
Resolution of sick building syndrome in a high-security facility.
Hiipakka, D W; Buffington, J R
2000-08-01
The main objective of this article is to serve as a case study for other industrial hygiene (IH) professionals' review as a "real world" effort in responding to a facility perceived as "sick" by its occupants. As many industrial hygienists do not have extensive backgrounds in evaluating microbial air contaminants or the mechanical function of building HVAC units, the overall intent is to provide "lessons learned" to IH generalists who may be asked to participate in indoor environmental quality (IEQ) surveys. In September 1994, a suspected case of "sick building syndrome" was investigated (with significant airborne fungal loads confirmed) at a communications center after numerous occupants reported upper respiratory disease and/or allergy-type symptoms. The setting was a two-story structure approximately 30 years old, with a normal occupancy load of 350 to 400 persons. In addition to continual structural modifications, the central HVAC air conditioning systems had poor maintenance histories. Inspection of HVAC components revealed visible fungal growth on air filters and air ducts and in cooling fan condensate drip pans. Fungal air samples were collected with an Anderson N6 air sampler and Sabouraund dextrose agar media. Over a study period of 23 months, three rounds of 26 air samples were collected for 5 minutes each at 28.3 liters/minute airflow. Cultures exhibited fungi such as Aspergillus, Penicillium, Alternaria, and Cladosporium. Certain strains of these fungi produce mycotoxins that may cause a variety of deleterious health effects such as those described by occupants. Initial 1994 airborne fungal concentrations ranged from 85 to 6157 colony forming units (CFUs) per cubic meter of sampled air (CFU/m3). Some investigators have reported fungal concentrations as low as 245 CFU/m3 associated with complaint sites in other buildings. Remediation efforts involved hiring a dedicated mechanic to implement a HVAC preventive maintenance program (including regular replacement of all HVAC air filters and cleaning of accessible components with water/bleach solution). Post-abatement January 1996 re-sampling revealed a significant drop in airborne fungal colonies up to 97 percent (range = 21 to 1092 CFUs/m3)--which also coincided with physicians at the local hospital sensing a qualitative reduction in patient visits from facility workers. To address seasonal bias, a final August 1996 air sample round revealed a range of 14 to 500 CFUs/m3. Of the 21 workspaces sampled in all three rounds, nine continued to show a decline in CFUs/m3 from September 1994 baseline counts. These results demonstrate the critical role of an ongoing HVAC maintenance program for reducing potential reservoirs of fungal organisms in indoor work environments. Building renovations (especially those involving major changes to building layout and usage) can adversely affect IEQ if plans do not include coordinated updates and regular preventive maintenance of HVAC systems. Eventual negative outcomes can be reduced occupant productivity and deleterious health effects.
1997-02-01
application with a strong resemblance to a video game , concern has been raised that prior video game experience might have a moderating effect on scores. Much...such as spatial ability. The effects of computer or video game experience on work sample scores have not been systematically investigated. The purpose...of this study was to evaluate the incremental validity of prior video game experience over that of general aptitude as a predictor of work sample test
Bennett, D. H.; Moran, R. E.; Wu, X. (May); Tulve, N. S.; Clifton, M. S.; Colón, M.; Weathers, W.; Sjödin, A.; Jones, R.; Hertz-Picciotto, I.
2016-01-01
Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in furniture foam, electronics, and other home furnishings. A field study was conducted that enrolled 139 households from California, which has had more stringent flame retardant requirements than other countries and areas. The study collected passive air, floor and indoor window surface wipes, and dust samples (investigator collected using an HVS3 and vacuum cleaner) in each home. PentaBDE and BDE209 were detected in the majority of the dust samples and many floor wipe samples, but the detection in air and window wipe samples was relatively low. Concentrations of each PBDE congener in different indoor environmental media were moderately correlated, with correlation coefficients ranging between 0.42 and 0.68. Correlation coefficients with blood levels were up to 0.65 and varied between environmental media and age group. Both investigator-collected dust and floor wipes were correlated with serum levels for a wide range of congeners. These two sample types also had a relatively high fraction of samples with adequate mass for reliable quantification. In 42 homes, PBDE levels measured in the same environmental media in the same home 1 year apart were statistically correlated (correlation coefficients: 0.57–0.90), with the exception of BDE209 which was not well correlated longitudinally. PMID:24832910
View of Expedition 15 FE Anderson performing the ANITA Experiment in the Node 1
2007-10-06
ISS015-E-32200 (6 Oct. 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, uses an air sample pump and 2.5 liter gas sample bag to gather and analyze air samples for the Analyzing Interferometer for Ambient Air (ANITA) experiment in the Unity node of the International Space Station.
Keedakkadan, Habeeb Rahman; Abe, Osamu
2015-04-30
The separation and purification of oxygen-argon mixtures are critical in the high-precision analysis of Δ(17) O and δ(O2 /Ar) for geochemical applications. At present, chromatographic methods are used for the separation and purification of oxygen-argon mixtures or pure oxygen, but these methods require the use of high-purity helium as a carrier gas. Considerable interest has been expressed in the development of a helium-free cryogenic separation of oxygen-argon mixtures in natural air samples. The precise and simplified cryogenic separation of oxygen-argon mixtures from natural air samples presented here was made possible using a single 5A (30/60 mesh) molecular sieve column. The method involves the trapping of eluted gases using molecular sieves at liquid nitrogen temperature, which is associated with isotopic fractionation. We tested the proposed method for the determination of isotopic fractionations during the gas exchange between water and atmospheric air at equilibrium. The dependency of fractionation was studied at different water temperatures and for different methods of equilibration (bubbling and stirring). Isotopic and molecular fractionations during gas desorption from molecular sieves were studied for different amounts and types of molecular sieves. Repeated measurements of atmospheric air yielded a reproducibility (±SD) of 0.021 ‰, 0.044 ‰, 15 per meg and 1.9 ‰ for δ(17) O, δ(18) O, Δ(17) O and δ(O2 /Ar) values, respectively. We applied the method to determine equilibrium isotope fractionation during gas exchange between air and water. Consistent δ(18) O and Δ(17) O results were obtained with the latest two studies, whereas there was a significant difference in δ(18) O values between seawater and deionized water. We have revised a helium-free, cryogenic separation of oxygen-argon mixtures in natural air samples for isotopic and molecular ratio analysis. The use of a single 13X (1/8" pellet) molecular sieve yielded the smallest isotopic and molecular fractionations, and this fractionation by molecular sieves can be corrected by the amount of molecular sieve used in the experiment. The reproducibility of the method was tested by the measurement of the oxygen isotope ratios of dissolved oxygen at equilibrium with atmospheric air. We confirmed that the choice of methods for making air-equilibrated water was not related to the magnitude of isotope fractionation, whereas there was a difference between seawater and deionized water. Copyright © 2015 John Wiley & Sons, Ltd.
Microbial assessment of cabin air quality on commercial airliners
NASA Technical Reports Server (NTRS)
La Duc, Myron T.; Stuecker, Tara; Bearman, Gregory; Venkateswaran, Kasthuri
2005-01-01
The microbial burdens of 69 cabin air samples collected from commercial airliners were assessed via conventional culture-dependent, and molecular-based microbial enumeration assays. Cabin air samples from each of four separate flights aboard two different carriers were collected via air-impingement. Microbial enumeration techniques targeting DNA, ATP, and endotoxin were employed to estimate total microbial burden. The total viable microbial population ranged from 0 to 3.6 x10 4 cells per 100 liters of air, as assessed by the ATP-assay. When these same samples were plated on R2A minimal medium, anywhere from 2% to 80% of these viable populations were cultivable. Five of the 29 samples examined exhibited higher cultivable counts than ATP derived viable counts, perhaps a consequence of the dormant nature (and thus lower concentration of intracellular ATP) of cells inhabiting these air cabin samples. Ribosomal RNA gene sequence analysis showed these samples to consist of a moderately diverse group of bacteria, including human pathogens. Enumeration of ribosomal genes via quantitative-PCR indicated that population densities ranged from 5 x 10 1 ' to IO 7 cells per 100 liters of air. Each of the aforementioned strategies for assessing overall microbial burden has its strengths and weaknesses; this publication serves as a testament to the power of their use in concert.
In April 2014, U.S. Environmental Protection Agency (EPA) environmental monitoring and assessment team members reviewed DOE's air sampling plan, visited DOE's air samplers and placed air samplers onsite near existing DOE samplers to corroborate results.
Yu, Hong-Li; Zhang, Qian; Jin, Yang-Ping; Wang, Kui-Long; Lu, Tu-Lin; Li, Lin
2016-07-01
In order to compare the effect of sulfur fumigation processing and direct hot air heating technology on puerarin contents and efficacy of Puerariae Thomsonii Radix, the fresh roots of Pueraria thomsonii were cut into small pieces and prepared into direct sunshine drying samples, direct hot air drying samples, and sulfur fumigation-hot air drying samples. Moisture contents of the samples were then determined. The puerarin contents of different samples were compared by HPLC method. Moreover, the models of drunkenness mice were established, and then with superoxide dismutase (SOD) content as the index, aqueous decoction extracts of Puerariae Thomsonii Radix samples with sulfur fumigation processing and non-sulfur fumigation processing methods were administrated by ig; the effects of sulfur fumigation on contents of SOD in mice liver and serum were determined, and the sulfur fumigation samples and non-sulfur fumigation samples were investigated for moth and mildew under different packaging and storage conditions. Results showed that the sulfur fumigation samples significantly changed the puerarin content from Puerariae Thomsonii Radix. The content of puerarin was decreased gradually when increasing the times of sulfur fumigation and amount of sulfur. SOD content in drunken mice liver and serum was significantly decreased when increasing the times of sulfur fumigation, showing significant difference with both direct sunshine drying group and direct hot air drying group. Moth and mildew were not found in the sulfur fumigation samples and direct hot air drying samples whose moisture contents were lower than the limit in Pharmacopoeia. Research showed that sulfur fumigation can significantly reduce the content of main active ingredients and reduce the efficacy of Puerariae Thomsonii Radix, indicating that the quality of Puerariae Thomsonii Radix was significantly decreased after sulfur fumigation. However, the contents of the main active ingredients, efficacy and storage results of the direct hot air drying samples were similar to those in direct sunshine drying samples, so the hot air drying process was a nice drying technology which could be promoted for use. Copyright© by the Chinese Pharmaceutical Association.
Claeson, A-S; Sunesson, A-L
2005-01-01
The Streptomyces spp. form a common group of bacteria found in the indoor air of water-damaged buildings. They are known for their capability to produce compounds, like geosmin, with low odor thresholds. In this study, two strains of Streptomyces albidoflavus were cultivated on pinewood, gypsum board, particle-board, sand and tryptone glucose extract agar (TGEA). Air samples from the cultures were collected on six different adsorbents and chemosorbents to sample a wide range of compounds such as VOCs, aldehydes, amines and lightweight organic acids. The samples were analyzed with gas chromatography, high-pressure liquid chromatography and ion chromatography. Mass spectrometry was used for identification of the compounds. Metabolites were found and identified in air samples from cultures on all materials except sand. Alcohols and ketones were the dominating compound groups produced by cultures grown on pinewood and gypsum board. Few metabolites were produced on particle-board. The culture growing on TGEA produced mainly sulfur compounds and sesquiterpenes. Ammonia, methylamine, diethylamine, ethylamine and one unidentifiable amine were also found from cultivation on TGEA. The growth medium was of crucial importance to the production of potentially irritating metabolites. Microbial growth and the production of volatile metabolites is one possible explanation for building-related health problems. Streptomyces spp. are frequently found in water-damaged buildings. This study shows that Streptomyces spp. are able to produce not only odorous compounds like geosmin, but also potentially irritating compounds. This finding should be of interest in indoor air investigations.
Glyphosate–rich air samples induce IL–33, TSLP and generate IL–13 dependent airway inflammation
Kumar, Sudhir; Khodoun, Marat; Kettleson, Eric M.; McKnight, Christopher; Reponen, Tiina; Grinshpun, Sergey A.; Adhikari, Atin
2014-01-01
Several low weight molecules have often been implicated in the induction of occupational asthma. Glyphosate, a small molecule herbicide, is widely used in the world. There is a controversy regarding a role of glyphosate in developing asthma and rhinitis among farmers, the mechanism of which is unexplored. The aim of this study was to explore the mechanisms of glyphosate induced pulmonary pathology by utilizing murine models and real environmental samples. C57BL/6, TLR4−/−, and IL-13−/− mice inhaled extracts of glyphosate-rich air samples collected on farms during spraying of herbicides or inhaled different doses of glyphosate and ovalbumin. The cellular response, humoral response, and lung function of exposed mice were evaluated. Exposure to glyphosate-rich air samples as well as glyphosate alone to the lungs increased: eosinophil and neutrophil counts, mast cell degranulation, and production of IL-33, TSLP, IL-13, and IL-5. In contrast, in vivo systemic IL-4 production was not increased. Co-administration of ovalbumin with glyphosate did not substantially change the inflammatory immune response. However, IL-13-deficiency resulted in diminished inflammatory response but did not have a significant effect on airway resistance upon methacholine challenge after 7 or 21 days of glyphosate exposure. Glyphosate-rich farm air samples as well as glyphosate alone were found to induce pulmonary IL-13-dependent inflammation and promote Th2 type cytokines, but not IL-4 for glyphosate alone. This study, for the first time, provides evidence for the mechanism of glyphosate-induced occupational lung disease. PMID:25172162
De Filippis, Patrizia; Spinaci, Anna; Coia, Maura; Maggi, Oriana; Panà, Augusto
2003-01-01
The microbiological quality of the air indoor is influenced from various factors and one of the most important is represented from the maintenance of the conditioning systems. In this study it has been estimated the effectiveness of an intervention of cleaning and maintenance on the systems of conditioning of an university building executing sampling before and after such intervention. The two results were confronted and it is observed as the maintenance of the air conditioners has influenced on the quality of the air indoor.
What measurements tell us about air composition and emissions in three US oil and gas fields
NASA Astrophysics Data System (ADS)
Petron, G.; Miller, B. R.; Montzka, S. A.; Dlugokencky, E. J.; Kofler, J.; Sweeney, C.; Karion, A.; Frost, G. J.; Helmig, D.; Hueber, J.; Schnell, R. C.; Conley, S. A.; Tans, P. P.
2013-12-01
In 2012 and 2013, the NOAA Global Monitoring Division and several collaborators conducted intensive airborne and ground campaigns in three US oil and gas plays to study emissions of methane and surface ozone precursors. In this presentation we will focus on the multiple species analysis in discrete air samples collected with the NOAA Mobile Laboratory (ML) and the light aircraft in the Uinta Basin (Utah), Denver Julesburg Basin (Colorado) and Barnett Shale (Texas). Hydrocarbon ratios in samples collected with the ML downwind of specific sources show significantly more variability than the aircraft samples. These surface samples provide some useful information about the composition of various sources in each region. Ratios of the non-methane hydrocarbons on the ground and higher in the boundary layer show some differences between the plays, which could be explained by the different composition of the raw gas being produced or by different mixes of sources contributions. Understanding the speciation of atmospheric emissions is critical to identify emission vectors and to assess their potential air quality and climate impacts. Our measurement results will be compared with data from other studies, including emission inventories.
An Improved, Automated Whole-Air Sampler and VOC Analysis System: Results from SONGNEX 2015
NASA Astrophysics Data System (ADS)
Lerner, B. M.; Gilman, J.; Tokarek, T. W.; Peischl, J.; Koss, A.; Yuan, B.; Warneke, C.; Isaacman-VanWertz, G. A.; Sueper, D.; De Gouw, J. A.; Aikin, K. C.
2015-12-01
Accurate measurement of volatile organic compounds (VOCs) in the troposphere is critical for the understanding of emissions and physical and chemical processes that can impact both air quality and climate. Airborne VOC measurements have proven challenging due to the requirements of short sample collection times (=10 s) to maximize spatial resolution and sampling frequency and high sensitivity (pptv) to chemically diverse hydrocarbons, halocarbons, oxygen- and nitrogen-containing VOCs. NOAA ESRL CSD has built an improved whole air sampler (iWAS) which collects compressed ambient air samples in electropolished stainless steel canisters, based on the NCAR HAIS Advanced Whole Air Sampler [Atlas and Blake]. Post-flight chemical analysis is performed with a custom-built gas chromatograph-mass spectrometer system that pre-concentrates analyte cryostatically via a Stirling cooler, an electromechanical chiller which precludes the need for liquid nitrogen to reach trapping temperatures. For the 2015 Shale Oil and Natural Gas Nexus Study (SONGNEX), CSD conducted iWAS measurements on 19 flights aboard the NOAA WP-3D aircraft between March 19th and April 27th. Nine oil and natural gas production regions were surveyed during SONGNEX and more than 1500 air samples were collected and analyzed. For the first time, we employed real-time mapping of sample collection combined with live data from fast time-response measurements (e.g. ethane) for more uniform surveying and improved target plume sampling. Automated sample handling allowed for more than 90% of iWAS canisters to be analyzed within 96 hours of collection - for the second half of the campaign improved efficiencies reduced the median sample age at analysis to 36 hours. A new chromatography peak-fitting software package was developed to minimize data reduction time by an order of magnitude without a loss of precision or accuracy. Here we report mixing ratios for aliphatic and aromatic hydrocarbons (C2-C8) along with select oxygenated species (alcohols and ketones) and cycloalkanes. We present an intercomparison of the GC-MS analysis system and iWAS samples from SONGNEX with a new H3O+ CIMS-TOF and a spectroscopic ethane measurement that also flew aboard the NOAA WP-3D aircraft during SONGNEX. We also consider the effect of sample age on observed mixing ratio.
The purpose of this SOP is to describe the methods used to collect indoor and outdoor air samples for the determination of selected volatile organic compounds (VOC's) using a pump to draw air through a Carbotrap Sampler. Volatile organic compounds (VOCs) present in the air are p...
NASA Astrophysics Data System (ADS)
Li, Jing; Zhou, Liantong; Zhang, Xiangyu; Xu, Caijia; Dong, Liming; Yao, Maosheng
2016-01-01
Air samples from twelve sampling sites (including seven intra-plant sites, one upwind site and four downwind sites) from a wastewater treatment plant (WWTP) in Beijing were collected using a Reuter Centrifugal Sampler High Flow (RCS); and their microbial fractions were studied using culturing and high throughput gene sequence. In addition, the viable (fluorescent) bioaerosol concentrations for 7 intra-plant sites were also monitored for 30 min each using an ultraviolet aerodynamic particle sizer (UV-APS). Both air and water samples collected from the plant were investigated for possible bacterial antibiotic resistance genes and integrons using polymerase chain reaction (PCR) coupled with gel electrophoresis. The results showed that the air near sludge thickening basin was detected to have the highest level of culturable bacterial aerosols (up to 1697 CFU/m3) and fungal aerosols (up to 930 CFU/m3). For most sampling sites, fluorescent peaks were observed at around 3-4 μm, except the office building with a peak at 1.5 μm, with a number concentration level up to 1233-6533 Particles/m3. About 300 unique bacterial species, including human opportunistic pathogens, such as Comamonas Testosteroni and Moraxella Osloensis, were detected from the air samples collected over the biological reaction basin. In addition, we have detected the sul2 gene resistant to cotrimoxazole (also known as septra, bactrim and TMP-SMX) and class 1 integrase gene from the air samples collected from the screen room and the biological reaction basin. Overall, the screen room, sludge thickening basin and biological reaction basin imposed significant microbial exposure risks, including those from airborne antibiotic resistance genes.
Is there evidence for man-made nanoparticles in the Dutch environment?
Bäuerlein, Patrick S; Emke, Erik; Tromp, Peter; Hofman, Jan A M H; Carboni, Andrea; Schooneman, Ferry; de Voogt, Pim; van Wezel, Annemarie P
2017-01-15
Only very limited information is available on measured environmental concentrations of nanoparticles. In this study, several environmental compartments in The Netherlands were probed for the presence of nanoparticles. Different types of water were screened for the presence of inorganic (Ag, Au, TiO 2 ) and organic nanoparticles (C 60 , C 70 , [6,6]-phenyl-C 61 -butyric acid octyl ester, [6,6]-phenyl-C 61 -butyric acid butyl ester, [6,6]-phenyl-C 61 -butyric acid methyl ester, [6,6]-bis-phenyl-C 61 -butyric acid methyl ester, [6,6]-phenyl-C 71 -butyric acid methyl ester, [6,6]-thienyl-C 61 -butyric acid methyl ester). Air samples were analysed for the presence of nanoparticulate Mo, Ag, Ce, W, Pd, Pt, Rh, Zn, Ti, Si, B as well as Fe and Cu. ICP-MS, Orbitrap-HRMS, SEM and EDX were used for this survey. Water samples included dune and bank filtrates, surface waters and ground waters as well as influents, effluents and sludge of sewage treatment plants (STPs), and surface waters collected near airports and harbours. Air samples included both urban and rural samples. C 60 was detected in air, sewage treatment plants, influents, effluents and sludge, but in no other aqueous samples despite the low detection limit of 0.1ng/L. C 70 and functionalised fullerenes were not detected at all. In STP sludge and influent the occurrence of Ag and Au nanoparticles was verified by SEM/EDX and ICP-MS. In air up to about 25m% of certain metals was found in the nanosize fraction. Overall, between 1 and 6% of the total mass from metals in the air samples was found in the size fraction <100nm. Copyright © 2016 Elsevier B.V. All rights reserved.
Remote possibly hazardous content container sampling device
Volz, David L.
1998-01-01
The present invention relates to an apparatus capable of sampling enclosed containers, where the contents of the container is unknown. The invention includes a compressed air device capable of supplying air pressure, device for controlling the amount of air pressure applied, a pneumatic valve, a sampling device having a hollow, sampling insertion needle suspended therein and device to communicate fluid flow between the container and a containment vessel, pump or direct reading instrument.
Development of Monitors for Assessing Exposure of Military Personnel to Toxic Chemicals.
2000-01-01
Residues " S ampler Preparation 7 Transfer and Analysis 7 Temperature Effects on PIMS Sampling Rate 8 Environmental Air Sampling 8 Results and...of exposure and potential toxicity to personnel. While progress has been made in improving active water and air sampling technology, such devices...streams, 3) the apparatus is also applicable for use in air sampling deployments in indoor and outdoor scenarios, and 4) the apparatus is commercially
Measuring the radon concentration in air meting van de radonconcentratie in lucht
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aten, J.B.T.; Bierhuizen, H.W.J.; Vanhoek, L.P.
1975-01-01
A simple transportable apparatus for measurement of the radon concentration in the air of a workshop was developed. An air sample is sucked through a filter and the decay curve of the alpha activity is measured. The counting speed 40 min after sampling gives an indication of the radon activity. The apparatus was calibrated by analyzing an analogous decay curve obtained with a big filter and a big air sample, the activity being measured with an anti-coincidence counter. (GRA)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Griffith, Stacy R.
The 2018 Annual Terrestrial Sampling Plan for Sandia National Laboratories/New Mexico on Kirtland Air Force Base has been prepared in accordance with the “Letter of Agreement Between Department of Energy, National Nuclear Security Administration, Sandia Field Office (DOE/NNSA/SFO) and 377th Air Base Wing (ABW), Kirtland Air Force Base (KAFB) for Terrestrial Sampling” (signed January 2017), Sandia National Laboratories, New Mexico (SNL/NM). The Letter of Agreement requires submittal of an annual terrestrial sampling plan.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Griffith, Stacy R.
The 2017 Annual Terrestrial Sampling Plan for Sandia National Laboratories/New Mexico on Kirtland Air Force Base has been prepared in accordance with the “Letter of Agreement Between Department of Energy, National Nuclear Security Administration, Sandia Field Office (DOE/NNSA/SFO) and 377th Air Base Wing (ABW), Kirtland Air Force Base (KAFB) for Terrestrial Sampling” (signed January 2017), Sandia National Laboratories, New Mexico (SNL/NM). The Letter of Agreement requires submittal of an annual terrestrial sampling plan.
Inertial impaction air sampling device
Dewhurst, Katharine H.
1990-01-01
An inertial impactor to be used in an air sampling device for collection of respirable size particles in ambient air which may include a graphite furnace as the impaction substrate in a small-size, portable, direct analysis structure that gives immediate results and is totally self-contained allowing for remote and/or personal sampling. The graphite furnace collects suspended particles transported through the housing by means of the air flow system, and these particles may be analyzed for elements, quantitatively and qualitatively, by atomic absorption spectrophotometry.
Inertial impaction air sampling device
Dewhurst, K.H.
1987-12-10
An inertial impactor to be used in an air sampling device for collection of respirable size particles in ambient air which may include a graphite furnace as the impaction substrate in a small-size, portable, direct analysis structure that gives immediate results and is totally self-contained allowing for remote and/or personal sampling. The graphite furnace collects suspended particles transported through the housing by means of the air flow system, and these particles may be analyzed for elements, quantitatively and qualitatively, by atomic absorption spectrophotometry. 3 figs.
Knight, G M; McIntyre, J M; Mulyani
2006-03-01
Diamine silver fluoride (Ag(NH3)2F), referred to as AgF, has been shown to reduce the incidence of caries in primary dentitions. The clinical application of this material has been limited by staining associated with both teeth and restorative materials. The application of potassium iodide (KI) after AgF eliminates stain formation. There is a lack of information as to how the addition of AgF followed by KI may affect the bond strength to dentine. The purpose of this study was to compare the bond strengths of auto cure glass ionomer cement to dentine surfaces that had been treated with AgF and KI and without treatment. Ten recently extracted human third molars were embedded into methyl methacrylate resin and sliced to form a square block of exposed dentine surfaces. Each of the four surfaces were treated by one of the following procedures: (a) etching with 37 per cent phosphoric acid; (b) applying GC dentine conditioner; (c) etching, followed by application of AgF/KI then washing off the precipitate and air drying; and (d) etching, applying AgF/KI and air drying the reaction products on the surface. Fuji VII auto cure glass ionomer cement was bonded onto each sample and fracture tested. The dentine samples treated with AgF/KI followed by washing away the precipitate and air drying had bond strengths (2.83 MPa) not significantly different from samples that had been conditioned (2.40 MPa). Samples where the AgF/KI precipitate had been air dried onto the dentine surface had significantly lower bond strengths (1.49 MPa) than the washed samples. Samples that were etched had significantly lower bond strengths (1.91MPa) than the conditioned samples. This study found that the application of AgF/KI to etched dentine samples followed by washing off the precipitate, created bond strengths that were not significantly different to conditioned samples. Leaving the AgF/KI precipitate on the dentine surface significantly reduced the bond strength of auto cured glass ionomer cement to dentine. Washing away the reaction products and air drying is recommended as the clinical protocol for using AgF and KI on dentine surfaces prior to application of an auto cure glass ionomer cement.
Bauer, Beth A; Besch-Williford, Cynthia; Livingston, Robert S; Crim, Marcus J; Riley, Lela K; Myles, Matthew H
2016-11-01
Sampling of bedding debris within the exhaust systems of ventilated racks may be a mechanism for detecting murine pathogens in colony animals. This study examined the effectiveness of detecting pathogens by PCR analysis of exhaust debris samples collected from ventilated racks of 2 different rack designs, one with unfiltered air flow from within the cage to the air-exhaust pathway, and the other had a filter between the cage and the air-exhaust pathway. For 12 wk, racks were populated with either 1 or 5 cages of mice (3 mice per cage) infected with one of the following pathogens: mouse norovirus (MNV), mouse parvovirus (MPV), mouse hepatitis virus (MHV), Helicobacter spp., Pasteurella pneumotropica, pinworms, Entamoeba muris, Tritrichomonas muris, and fur mites. Pathogen shedding by infected mice was monitored throughout the study. In the filter-containing rack, PCR testing of exhaust plenums yielded negative results for all pathogens at all time points of the study. In the rack with open air flow, pathogens detected by PCR analysis of exhaust debris included MHV, Helicobacter spp., P. pneumotropica, pinworms, enteric protozoa, and fur mites; these pathogens were detected in racks housing either 1 or 5 cages of infected mice. Neither MPV nor MNV was detected in exhaust debris, even though prolonged viral shedding was confirmed. These results demonstrate that testing rack exhaust debris from racks with unfiltered air flow detected MHV, enteric bacteria and parasites, and fur mites. However, this method failed to reliably detect MNV or MPV infection of colony animals.
Bauer, Beth A; Besch-Williford, Cynthia; Livingston, Robert S; Crim, Marcus J; Riley, Lela K; Myles, Matthew H
2016-01-01
Sampling of bedding debris within the exhaust systems of ventilated racks may be a mechanism for detecting murine pathogens in colony animals. This study examined the effectiveness of detecting pathogens by PCR analysis of exhaust debris samples collected from ventilated racks of 2 different rack designs, one with unfiltered air flow from within the cage to the air-exhaust pathway, and the other had a filter between the cage and the air-exhaust pathway. For 12 wk, racks were populated with either 1 or 5 cages of mice (3 mice per cage) infected with one of the following pathogens: mouse norovirus (MNV), mouse parvovirus (MPV), mouse hepatitis virus (MHV), Helicobacter spp., Pasteurella pneumotropica, pinworms, Entamoeba muris, Tritrichomonas muris, and fur mites. Pathogen shedding by infected mice was monitored throughout the study. In the filter-containing rack, PCR testing of exhaust plenums yielded negative results for all pathogens at all time points of the study. In the rack with open air flow, pathogens detected by PCR analysis of exhaust debris included MHV, Helicobacter spp., P. pneumotropica, pinworms, enteric protozoa, and fur mites; these pathogens were detected in racks housing either 1 or 5 cages of infected mice. Neither MPV nor MNV was detected in exhaust debris, even though prolonged viral shedding was confirmed. These results demonstrate that testing rack exhaust debris from racks with unfiltered air flow detected MHV, enteric bacteria and parasites, and fur mites. However, this method failed to reliably detect MNV or MPV infection of colony animals. PMID:27931317
Use Of The Operational Air Quality Monitor (AQM) For In-Flight Water Testing Project
NASA Technical Reports Server (NTRS)
Macatangay, Ariel
2014-01-01
A primary requirement for manned spaceflight is Environmental Health which ensures air and water contaminants, acoustic profiles, microbial flora, and radiation exposures within the cabin are maintained to levels needed for crew health and for vehicle system functionality. The reliance on ground analyses of returned samples is a limitation in the current environmental monitoring strategy that will prevent future Exploration missions beyond low-Earth orbit. This proposal attempts to address this shortcoming by advancing in-flight analyses of water and air. Ground analysis of in-flight, air and water samples typically employ vapor-phase analysis by gas chromatography-mass spectrometry (GC-MS) to identify and quantify organic compounds present in the samples. We envision the use of newly-developed direct ionization approaches as the most viable avenue leading towards an integrated analytical platform for the monitoring of water, air, and, potentially bio-samples in the cabin environment. Development of an in-flight instrument capable of analyzing air and water samples would be the logical next step to meeting the environmental monitoring needs of Exploration missions. Currently, the Air Quality Monitor (AQM) on-board ISS provides this specific information for a number of target compounds in the air. However, there is a significant subset of common target compounds between air and water. Naturally, the following question arises, "Can the AQM be used for both air and water quality monitoring?" Previous directorate-level IR&D funding led to the development of a water sample introduction method for mass spectrometry using electrothermal vaporization (ETV). This project will focus on the integration of the ETV with a ground-based AQM. The capabilities of this integrated platform will be evaluated using a subset of toxicologically important compounds.
NASA Astrophysics Data System (ADS)
Ling, Tsz Yan; Zuo, Zhili; Pui, David Y. H.
2013-04-01
Nanoscale particles can be found in the air-borne, liquid-borne and surface-borne dispersed phases. Measurement techniques for nanoscale particles in all three dispersed phases are needed for the environmental, health and safety studies of nanomaterials. We present our studies on connecting the nanoparticle measurements in different phases to enhance the characterization capability. Microscopy analysis for particle morphology can be performed by depositing air-borne or liquid-borne nanoparticles on surfaces. Detection limit and measurement resolution of the liquid-borne nanoparticles can be enhanced by aerosolizing them and taking advantage of the well-developed air-borne particle analyzers. Sampling electrically classified air-borne virus particles with a gelatin filter provides higher collection efficiency than a liquid impinger.
Pankow, J.F.; Luo, W.; Bender, D.A.; Isabelle, L.M.; Hollingsworth, J.S.; Chen, C.; Asher, W.E.; Zogorski, J.S.
2003-01-01
The ambient air concentrations of 88 volatile organic compounds were determined in samples taken at 13 semi-rural to urban locations in Maine, Massachusetts, New Jersey, Pennsylvania, Ohio, Illinois, Louisiana, and California. The sampling periods ranged from 7 to 29 months, yielding a large data set with a total of 23,191 individual air concentration values, some of which were designated "ND" (not detected). For each compound at each sampling site, the air concentrations (ca, ppbV) are reported in terms of means, medians, and means of the detected values. The analytical method utilized adsorption/thermal desorption with air-sampling cartridges. The analytes included numerous halogenated alkanes, halogenated alkenes, ethers, alcohols, nitriles, esters, ketones, aromatics, a disulfide, and a furan. At some sites, the air concentrations of the gasoline-related aromatic compounds and the gasoline additive methyl tert-butyl ether were seasonally dependent, with concentrations that maximized in the winter. For each site studied here, the concentrations of some compounds were highly correlated one with another (e.g., the BTEX group (benzene, toluene, ethylbenzene, and the xylenes). Other aromatic compounds were also all generally correlated with one another, while the concentrations of other compound pairs were not correlated (e.g., benzene was not correlated with CFC-12). The concentrations found for the BTEX group were generally lower than the values that have been previously reported for urbanized and industrialized areas of other nations. ?? 2003 Elsevier Ltd. All rights reserved.
Heo, Jongbae; Wu, Bo; Abdeen, Ziad; Qasrawi, Radwan; Sarnat, Jeremy A; Sharf, Geula; Shpund, Kobby; Schauer, James J
2017-06-01
This manuscript evaluates spatial and temporal variations of source contributions to ambient fine particulate matter (PM 2.5 ) in Israeli, Jordanian, and Palestinian cities. Twenty-four hour integrated PM 2.5 samples were collected every six days over a 1-year period (January to December 2007) in four cities in Israel (West Jerusalem, Eilat, Tel Aviv, and Haifa), four cities in Jordan (Amman, Aqaba, Rahma, and Zarka), and three cities in Palestine (Nablus, East Jerusalem, and Hebron). The PM 2.5 samples were analyzed for major chemical components, including organic carbon and elemental carbon, ions, and metals, and the results were used in a positive matrix factorization (PMF) model to estimate source contributions to PM 2.5 mass. Nine sources, including secondary sulfate, secondary nitrate, mobile, industrial lead sources, dust, construction dust, biomass burning, fuel oil combustion and sea salt, were identified across the sampling sites. Secondary sulfate was the dominant source, contributing 35% of the total PM 2.5 mass, and it showed relatively homogeneous temporal trends of daily source contribution in the study area. Mobile sources were found to be the second greatest contributor to PM 2.5 mass in the large metropolitan cities, such as Tel Aviv, Hebron, and West and East Jerusalem. Other sources (i.e. industrial lead sources, construction dust, and fuel oil combustion) were closely related to local emissions within individual cities. This study demonstrates how international cooperation can facilitate air pollution studies that address regional air pollution issues and the incremental differences across cities in a common airshed. It also provides a model to study air pollution in regions with limited air quality monitoring capacity that have persistent and emerging air quality problems, such as Africa, South Asia and Central America. Copyright © 2017 Elsevier Ltd. All rights reserved.
This Paper covers the basics of passive sampler design, compares passive samplers to conventional methods of air sampling, and discusses considerations when implementing a passive sampling program. The Paper also discusses field sampling and sample analysis considerations to ensu...
Brun, C P; Miron, D; Silla, L M R; Pasqualotto, A C
2013-04-01
Invasive fungal diseases have emerged as important causes of morbidity and mortality in haematological patients. In this study air samples were collected in two haematopoietic stem cell transplantation (HSCT) units, in which distinct air-control systems were in place. In hospital 1 no high-efficiency particulate air (HEPA) filter was available whereas in hospital 2 HSCT rooms were equipped with HEPA filters, with positive air pressure in relation to the corridor. A total of 117 samples from rooms, toilets and corridors were obtained during December 2009 to January 2011, using a six-stage Andersen sampler. In both hospitals, the concentration of potentially pathogenic fungi in the air was reduced in patients' rooms compared to corridors (P < 0·0001). Despite the presence of a HEPA filter in hospital 2, rooms in both hospitals showed similar concentrations of potentially pathogenic fungi (P = 0·714). These findings may be explained by the implementation of additional protective measures in hospital 1, emphasizing the importance of such measures in protected environments.
An investigation of the source of air Ar contamination in KAr dating
Mussett, A.E.; Brent, Dalrymple G.
1968-01-01
Precision of young KAr ages is limited by air argon contamination. A series of experiments in which the exposure of basalt and sanidine samples to air argon was controlled, shows that most of the air contamination does not arise in the laboratory. Because of this, it seems unlikely that air argon contamination can be significantly reduced by special sample handling and preparation techniques. ?? 1968.
NASA Astrophysics Data System (ADS)
Aliyu, Yahaya A.; Botai, Joel O.
2018-04-01
The retrieval characteristics for a city-scale satellite experiment was explored over a Nigerian city. The study evaluated carbon monoxide and aerosol contents in the city atmosphere. We utilized the MSA Altair 5× gas detector and CW-HAT200 particulate counter to investigate the city-scale monitoring capabilities of satellite pollution observing instruments; atmospheric infrared sounder (AIRS), measurement of pollution in the troposphere (MOPITT), moderate resolution imaging spectroradiometer (MODIS), multi-angle imaging spectroradiometer (MISR) and ozone monitoring instrument (OMI). To achieve this, we employed the Kriging interpolation technique to collocate the satellite pollutant estimations over 19 ground sample sites for the period of 2015-2016. The portable pollutant devices were validated using the WHO air filter sampling model. To determine the city-scale performance of the satellite datasets, performance indicators: correlation coefficient, model efficiency, reliability index and root mean square error, were adopted as measures. The comparative analysis revealed that MOPITT carbon monoxide (CO) and MODIS aerosol optical depth (AOD) estimates are the appropriate satellite measurements for ground equivalents in Zaria, Nigeria. Our findings were within the acceptable limits of similar studies that utilized reference stations. In conclusion, this study offers direction to Nigeria's air quality policy organizers about available alternative air pollution measurements for mitigating air quality effects within its limited resource environment.
THE NEW YORK CITY URBAN DISPERSION PROGRAM MARCH 2005 FIELD STUDY: TRACER METHODS AND RESULTS.
DOE Office of Scientific and Technical Information (OSTI.GOV)
WATSON, T.B.; HEISER, J.; KALB, P.
The Urban Dispersion Program March 2005 Field Study tracer releases, sampling, and analytical methods are described in detail. There were two days where tracer releases and sampling were conducted. A total of 16.0 g of six tracers were released during the first test day or Intensive Observation Period (IOP) 1 and 15.7 g during IOP 2. Three types of sampling instruments were used in this study. Sequential air samplers, or SAS, collected six-minute samples, while Brookhaven atmospheric tracer samplers (BATS) and personal air samplers (PAS) collected thirty-minute samples. There were a total of 1300 samples resulting from the two IOPs.more » Confidence limits in the sampling and analysis method were 20% as determined from 100 duplicate samples. The sample recovery rate was 84%. The integrally averaged 6-minute samples were compared to the 30-minute samples. The agreement was found to be good in most cases. The validity of using a background tracer to calculate sample volumes was examined and also found to have a confidence level of 20%. Methods for improving sampling and analysis are discussed. The data described in this report are available as Excel files. An additional Excel file of quality assured tracer data for use in model validation efforts is also available. The file consists of extensively quality assured BATS tracer data with background concentrations subtracted.« less
Golemba, Marcelo D; Culasso, Andrés C A; Villamil, Federico G; Bare, Patricia; Gadano, Adrián; Ridruejo, Ezequiel; Martinez, Alfredo; Di Lello, Federico A; Campos, Rodolfo H
2013-01-01
The estimated prevalence of HCV infection in Argentina is around 2%. However, higher rates of infection have been described in population studies of small urban and rural communities. The aim of this work was to compare the origin and diversification of HCV-1b in samples from two different epidemiological scenarios: Buenos Aires, a large cosmopolitan city, and O'Brien, a small rural town with a high prevalence of HCV infection. The E1/E2 and NS5B regions of the viral genome from 83 patients infected with HCV-1b were sequenced. Phylogenetic analysis and Bayesian Coalescent methods were used to study the origin and diversification of HCV-1b in both patient populations. Samples from Buenos Aires showed a polyphyletic behavior with a tMRCA around 1887-1900 and a time of spread of infection approximately 60 years ago. In contrast, samples from ÓBrien showed a monophyletic behavior with a tMRCA around 1950-1960 and a time of spread of infection more recent than in Buenos Aires, around 20-30 years ago. Phylogenetic and coalescence analysis revealed a different behavior in the epidemiological histories of Buenos Aires and ÓBrien. HCV infection in Buenos Aires shows a polyphyletic behavior and an exponential growth in two phases, whereas that in O'Brien shows a monophyletic cluster and an exponential growth in one single step with a more recent tMRCA. The polyphyletic origin and the probability of encountering susceptible individuals in a large cosmopolitan city like Buenos Aires are in agreement with a longer period of expansion. In contrast, in less populated areas such as O'Brien, the chances of HCV transmission are strongly restricted. Furthermore, the monophyletic character and the most recent time of emergence suggest that different HCV-1b ancestors (variants) that were in expansion in Buenos Aires had the opportunity to colonize and expand in O'Brien.
40 CFR 91.420 - CVS concept of exhaust gas sampling system.
Code of Federal Regulations, 2013 CFR
2013-07-01
... that complete mixing of the engine exhaust and background air is assured prior to the sampling probe.... The background probe must draw a representative sample of the background air during each sampling mode...) sampling system. If a critical flow venturi (CFV) is used on the dilute exhaust sample probe, this system...
40 CFR 91.420 - CVS concept of exhaust gas sampling system.
Code of Federal Regulations, 2010 CFR
2010-07-01
... that complete mixing of the engine exhaust and background air is assured prior to the sampling probe.... The background probe must draw a representative sample of the background air during each sampling mode...) sampling system. If a critical flow venturi (CFV) is used on the dilute exhaust sample probe, this system...
40 CFR 91.420 - CVS concept of exhaust gas sampling system.
Code of Federal Regulations, 2014 CFR
2014-07-01
... that complete mixing of the engine exhaust and background air is assured prior to the sampling probe.... The background probe must draw a representative sample of the background air during each sampling mode...) sampling system. If a critical flow venturi (CFV) is used on the dilute exhaust sample probe, this system...
40 CFR 91.420 - CVS concept of exhaust gas sampling system.
Code of Federal Regulations, 2011 CFR
2011-07-01
... that complete mixing of the engine exhaust and background air is assured prior to the sampling probe.... The background probe must draw a representative sample of the background air during each sampling mode...) sampling system. If a critical flow venturi (CFV) is used on the dilute exhaust sample probe, this system...
40 CFR 91.420 - CVS concept of exhaust gas sampling system.
Code of Federal Regulations, 2012 CFR
2012-07-01
... that complete mixing of the engine exhaust and background air is assured prior to the sampling probe.... The background probe must draw a representative sample of the background air during each sampling mode...) sampling system. If a critical flow venturi (CFV) is used on the dilute exhaust sample probe, this system...
Pleil, Joachim D; Lorber, Matthew N
2007-11-01
The United States Environmental Protection Agency collected ambient air samples in lower Manhattan for about 9 months following the September 11, 2001 World Trade Center (WTC) attacks. Measurements were made of a host of airborne contaminants including volatile organic compounds, polycyclic aromatic hydrocarbons, asbestos, lead, and other contaminants of concern. The present study focuses on the broad class of polychlorinated dibenzo-p-dioxins (CDDs) and dibenzofurans (CDFs) with specific emphasis on the 17 CDD/CDF congeners that exhibit mammalian toxicity. This work is a statistical study comparing the internal patterns of CDD/CDFs using data from an unambiguous fire event (WTC) and other data sets to help identify their sources. A subset of 29 samples all taken between September 16 and October 31, 2001 were treated as a basis set known to be heavily impacted by the WTC building fire source. A second basis set was created using data from Los Angeles and Oakland, CA as published by the California Air Resources Board (CARB) and treated as the archetypical background pattern for CDD/CDFs. The CARB data had a congener profile appearing similar to background air samples from different locations in America and around the world and in different matrices, such as background soils. Such disparate data would normally be interpreted with a qualitative pattern recognition based on congener bar graphs or other forms of factor or cluster analysis that group similar samples together graphically. The procedure developed here employs aspects of those statistical methods to develop a single continuous output variable per sample. Specifically, a form of variance structure-based cluster analysis is used to group congeners within samples to reduce collinearity in the basis sets, new variables are created based on these groups, and multivariate regression is applied to the reduced variable set to determine a predictive equation. This equation predicts a value for an output variable, OPT: the predicted value of OPT is near zero (0.00) for a background congener profile and near one (1.00) forthe profile characterized by the WTC air profile. Although this empirical method is calibrated with relatively small sets of airborne samples, it is shown to be generalizable to other WTC, fire source, and background air samples as well as other sample matrices including soils, window films and other dust wipes, and bulk dusts. However, given the limited data set examined, the method does not allow further discrimination between the WTC data and the other fire sources. This type of analysis is demonstrated to be useful for complex trace-level data sets with limited data and some below-detection entries.
In-vehicle VOCs composition of unconditioned, newly produced cars.
Brodzik, Krzysztof; Faber, Joanna; Łomankiewicz, Damian; Gołda-Kopek, Anna
2014-05-01
The in-vehicle volatile organic compounds (VOCs) concentrations gains the attention of both car producers and users. In the present study, an attempt was made to determine if analysis of air samples collected from an unconditioned car cabin can be used as a quality control measure. The VOCs composition of in-vehicle air was analyzed by means of active sampling on Carbograph 1TD and Tenax TA sorbents, followed by thermal desorption and simultaneous analysis on flame ionization and mass detector (TD-GC/FID-MS). Nine newly produced cars of the same brand and model were chosen for this study. Within these, four of the vehicles were equipped with identical interior materials and five others differed in terms of upholstery and the presence of a sunroof; one car was convertible. The sampling event took place outside of the car assembly plant and the cars tested left the assembly line no later than 24 hr before the sampling took place. More than 250 compounds were present in the samples collected; the identification of more than 160 was confirmed by comparative mass spectra analysis and 80 were confirmed by both comparison with single/multiple compounds standards and mass spectra analysis. In general, aliphatic hydrocarbons represented more than 60% of the total VOCs (TVOC) determined. Depending on the vehicle, the concentration of aromatic hydrocarbons varied from 12% to 27% of total VOCs. The very short period between car production and sampling of the in-vehicle air permits the assumption that the entire TVOC originates from off-gassing of interior materials. The results of this study expand the knowledge of in-vehicle pollution by presenting information about car cabin air quality immediately after car production. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.
Detection of respiratory viruses on air filters from aircraft.
Korves, T M; Johnson, D; Jones, B W; Watson, J; Wolk, D M; Hwang, G M
2011-09-01
To evaluate the feasibility of identifying viruses from aircraft cabin air, we evaluated whether respiratory viruses trapped by commercial aircraft air filters can be extracted and detected using a multiplex PCR, bead-based assay. The ResPlex II assay was first tested for its ability to detect inactivated viruses applied to new filter material; all 18 applications of virus at a high concentration were detected. The ResPlex II assay was then used to test for 18 respiratory viruses on 48 used air filter samples from commercial aircraft. Three samples tested positive for viruses, and three viruses were detected: rhinovirus, influenza A and influenza B. For 33 of 48 samples, internal PCR controls performed suboptimally, suggesting sample matrix effect. In some cases, influenza and rhinovirus RNA can be detected on aircraft air filters, even more than 10 days after the filters were removed from aircraft. With protocol modifications to overcome PCR inhibition, air filter sampling and the ResPlex II assay could be used to characterize viruses in aircraft cabin air. Information about viruses in aircraft could support public health measures to reduce disease transmission within aircraft and between cities. © The MITRE corporation. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.
Assessment of dioxin-like activity in ambient air particulate matter using recombinant yeast assays
NASA Astrophysics Data System (ADS)
Olivares, Alba; van Drooge, Barend L.; Pérez Ballesta, Pascual; Grimalt, Joan O.; Piña, Benjamin
2011-01-01
Ectopic activation of the aryl hydrocarbon receptor (AhR), also known as dioxin-like activity, is a major component of the toxicity associated with polycyclic aromatic hydrocarbons (PAH). Filtration of ambient air particulate matter through PM 10 filters followed by chemical determination of PAH concentrations and a yeast-based bioassay (RYA) were combined to evaluate and characterize dioxin-like activity in ambient air. Samples were collected in a semirural area of Northern Italy between September 2008 and February 2009. Total PAH contents ranged between 0.3 ng m -3 and 34 ng m -3 and were in correlation with seasonal variations of meteorological conditions and combustion processes. Dioxin-like activity values in air samples showed an excellent correlation (0.71 < R2 < 0.86) with the observed PAH concentrations and the predicted toxicity equivalents for PAH. This RYA-bioassay reported in the present study provides a simple and low-cost routine control for toxic PAH emissions, even at background air concentration levels.
Moorman, William J; Reutman, Susan S; Shaw, Peter B; Blade, Leo Michael; Marlow, David; Vesper, Hubert; Clark, John C; Schrader, Steven M
2012-01-01
The aim of this study was to evaluate biomarkers of acrylamide exposure, including hemoglobin adducts and urinary metabolites in acrylamide production workers. Biomarkers are integrated measures of the internal dose, and it is total acrylamide dose from all routes and sources that may present health risks. Workers from three companies were studied. Workers potentially exposed to acrylamide monomer wore personal breathing-zone air samplers. Air samples and surface-wipe samples were collected and analyzed for acrylamide. General-area air samples were collected in chemical processing units and control rooms. Hemoglobin adducts were isolated from ethylenediamine teraacetic acid (EDTA)-whole blood, and adducts of acrylamide and glycidamide, at the N-terminal valines of hemoglobin, were cleaved from the protein chain by use of a modified Edman reaction. Full work-shift, personal breathing zone, and general-area air samples were collected and analyzed for particulate and acrylamide monomer vapor. The highest general-area concentration of acrylamide vapor was 350 μg/cm(3) in monomer production. Personal breathing zone and general-area concentrations of acrylamide vapor were found to be highest in monomer production operations, and lower levels were in the polymer production operations. Adduct levels varied widely among workers, with the highest in workers in the monomer and polymer production areas. The acrylamide adduct range was 15-1884 pmol/g; glycidamide adducts ranged from 17.8 to 1376 p/mol/g. The highest acrylamide and glycidamide adduct levels were found among monomer production process operators. The primary urinary metabolite N-acetyl-S-(2-carbamoylethyl) cysteine (NACEC) ranged from the limit of detection to 15.4 μg/ml. Correlation of workplace exposure and sentinel health effects is needed to determine and control safe levels of exposure for regulatory standards.
Jamali, Hossein; Paydar, Mohammadjavad; Ismail, Salmah; Looi, Chung Yeng; Wong, Won Fen; Radmehr, Behrad; Abedini, Atefeh
2015-07-25
The aim of this study was to investigate the prevalence and characterization of Listeria species and Listeria monocytogenes isolated from raw fish and open-air fish market environments. Eight hundred and sixty two samples including raw fish and fish market environments (samples from workers' hands, workers' knives, containers and work surface) were collected from the open-air fish markets in the Northern region of Iran. Listeria spp. was isolated from 104/488 (21.3%) raw fish and 29/374 (7.8%) of samples from open-air fish market environment. The isolates of Listeria spp. included L. innocua (35.3%), L. monocytogenes (32.3%), L. seeligeri (18%), and L. ivanovii (14.3%). Of the 43 L. monocytogenes isolates, 31 (72.1%), 10 (23.3%) and 2 (4.7%) belonged to serovars 1/2a, 4b, and 1/2b, respectively. The inlA, inlB, inlC, inlJ, actA, hlyA, iap, plcA, and prfA virulence-associated genes were detected in almost all of the L. monocytogenes isolates. The Listeria spp. isolates showed high resistance against tetracycline (23.3%), penicillin G, and cephalothin (each 16.5%). Besides, we observed significant resistance level to tetracycline (27.9%), ampicillin (20.9%), cephalothin, penicillin G, and streptomycin (each 16.3%) in the L. monocytogenes isolates. All of the isolates were susceptible to cefotaxime, gentamicin, kanamycin, and pefloxacin. We found that tetM (25.6%), tetA (23.3%), ampC (14%), and penA (11.6%) were the most prevalent antibiotic resistance genes in the L. monocytogenes isolates. Recovery of potentially pathogenic L. monocytogenes from raw fish and environment of open-air fish market samples in this study is a convincing evidence for the zoonotic potential of listeriosis.
The effects of an energy efficiency retrofit on indoor air quality.
Frey, S E; Destaillats, H; Cohn, S; Ahrentzen, S; Fraser, M P
2015-04-01
To investigate the impacts of an energy efficiency retrofit, indoor air quality and resident health were evaluated at a low-income senior housing apartment complex in Phoenix, Arizona, before and after a green energy building renovation. Indoor and outdoor air quality sampling was carried out simultaneously with a questionnaire to characterize personal habits and general health of residents. Measured indoor formaldehyde levels before the building retrofit routinely exceeded reference exposure limits, but in the long-term follow-up sampling, indoor formaldehyde decreased for the entire study population by a statistically significant margin. Indoor PM levels were dominated by fine particles and showed a statistically significant decrease in the long-term follow-up sampling within certain resident subpopulations (i.e. residents who report smoking and residents who had lived longer at the apartment complex). © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Toxicity studies of a polyurethane rigid foam
NASA Technical Reports Server (NTRS)
Hilado, C. J.; Schneider, J. E.
1977-01-01
Relative toxicity tests were performed on a polyurethane foam containing a trimethylopropane-based polyol and an organophosphate flame retardant. The routine screening procedure involved the exposure of four Swiss albino male mice in a 4.2 liter hemispherical chamber to the products generated by pyrolyzing a 1.00 g sample at a heating rate of 40 deg C/min from 200 to 800 C in the absence of air flow. In addition to the routine screening, experiments were performed with a very rapid rise to 800 C, with nominal 16 and 48 ml/sec air flow and with varying sample rates. No unusual toxicity was observed with either gradual or rapid pyrolysis to 800 C. Convulsions and seizures similar to those previously reported were observed when the materials were essentially flash pyrolyzed at 800 C in the presence of air flow, and the toxicity appeared unusual because of low sample weights required to produce death.
BIOGENIC CONTRIBUTIONS TO ATMOSPHERIC VOLATILE ORGANIC COMPOUNDS IN AZUSA CA
An objective of the 1997 Southern California Ozone Study (SCOS97) was to provide an up-to-date assessment of the importance of biogenic emissions for tropospheric ozone production in the South Coast Air Basin. To this end ambient air samples were collected during September 199...
Fungal diversity and Aspergillus species in hospital environments.
Martínez-Herrera, Erick Obed; Frías De-León, María Guadalupe; Duarte-Escalante, Esperanza; Calderón-Ezquerro, María Del Carmen; Jiménez-Martínez, María Del Carme; Acosta-Altamirano, Gustavo; Rivera-Becerril, Facundo; Toriello, Conchita; Reyes Montes, María Del Rocío
2016-06-02
Nosocomial invasive fungal infections, particularly aspergillosis, are an increasing problem in immunocompromised patients. The presented study evaluates fungal diversity and the presence of Aspergillus in air samples from two hospitals. Over the course of one year (rainy and dry seasons), the air was sampled from three areas in two hospitals (1 and 2) using a single-stage Andersen viable particle sampler (Thermo Scientific, Waltham, MA, USA). The fungi were identified by macro- and micromorphology, and the number of colony forming units (CFU)/m(3) air and their richness, abundance, and diversity were determined. Isolates Aspergillus genus were characterized by their thermotolerance. The CFU/m(3) air was similar at both hospitals during the two seasons, but different between the sampled areas. Results showed 10 fungal genera for hospital 1, and 8 for hospital 2. The most abundant were Penicillium, Cladosporium and Aspergillus. The thermotolerance test confirmed the identification of A. fumigatus section Fumigati. The highest growth rate was found in Aspergillus section Nigri. Determining the fungal diversity in the two hospitals was important because all the species have the potential to be pathogenic, especially the section Fumigati.
NASA Astrophysics Data System (ADS)
van Vliet, E. D. S.; Kinney, P. L.
2007-10-01
Air quality is a serious and worsening problem in the rapidly growing cities of sub-Saharan Africa (SSA). However, the lack of ambient monitoring data, and particularly urban roadside concentrations for particulate matter in SSA cities severely hinders our ability to describe temporal and spatial patterns of concentrations, characterize exposure response relationships for key health outcomes, estimate disease burdens, and promote policy initiatives to address air quality. As part of a collaborative transportation planning exercise between Columbia University and the University of Nairobi, air monitoring was carried out in February 2006 in Nairobi, Kenya. The objective of the monitoring was to collect pilot data on air concentrations (PM2.5 and black carbon) encountered while driving in the Nairobi metropolitan area, and to compare those data to simultaneous 'urban background' concentrations measured in Nairobi but away from roadways. For both the background and roadway monitoring, we used portable air sampling systems that collect integrated filter samples. Results from this pilot study found that roadway concentrations of PM2.5 were approximately 20-fold higher than those from the urban background site, whereas black carbon concentrations differed by 10-fold. If confirmed by more extensive sampling, these data would underscore the need for air quality and transportation planning and management directed at mitigating roadway pollution.
Hedmer, Maria; Ludvigsson, Linus; Isaxon, Christina; Nilsson, Patrik T; Skaug, Vidar; Bohgard, Mats; Pagels, Joakim H; Messing, Maria E; Tinnerberg, Håkan
2015-08-01
The industrial use of novel-manufactured nanomaterials such as carbon nanotubes and carbon nanodiscs is increasing globally. Occupational exposure can occur during production, downstream use, and disposal. The health effects of many nanomaterials are not yet fully characterized and to handle nano-objects, their aggregates and agglomerates >100nm (NOAA), a high degree of control measures and personal protective equipment are required. The emission of airborne NOAA during production and handling can contaminate workplace surfaces with dust, which can be resuspended resulting in secondary inhalation exposures and dermal exposures. This study surveys the presence of carbon-based nanomaterials, such as multi-walled carbon nanotubes (MWCNTs) and carbon nanodiscs, as surface contamination at a small-scale producer using a novel tape sampling method. Eighteen different surfaces at a small-scale producer were sampled with an adhesive tape sampling method. The surfaces selected were associated with the production and handling of MWCNT powder in the near-field zone. Surfaces in the far-field zone were also sampled. In addition, tape stripping of the skin was performed on one worker. The tape samples were analysed with scanning electron microscopy to detect the carbon-based NOAA. Air sampling with a personal impactor was also performed on a worker who was producing MWCNTs the same day as the tape samples were collected. MWCNTs were detected in 50% of the collected tape samples and carbon nanodiscs in 17%. MWCNTs and carbon nanodiscs were identified in all parts of the workplace, thus, increasing the risk for secondary inhalation and dermal exposure of the workers. Both airborne MWCNTs and carbon nanodiscs were detected in the personal impactor samples. The tape-strip samples from the worker showed no presence of carbon-containing nanoparticles. Tape sampling is a functional method for detecting surface contamination of carbon-based NOAA and for exposure control during production at potentially any workplace that produces or handles such manufactured nanomaterials. With the tape method, it is possible to monitor if a potential for secondary inhalation exposure or dermal exposure exists through resuspension of dust deposited on workplace surfaces. By means of air sampling, we could confirm that carbon nanodiscs were resuspended into the air at the workplace even though they were not handled during that particular work shift. MWCNTs were detected in the air samples, but can have been derived from either resuspension or from the work tasks with MWCNTs that were performed during the air sampling. Tape sampling is a complementary method to air sampling and together these two methods provide a better view of the hygienic situation in workplaces where NOAA can be emitted into work environments. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
Stevens, C. M. [Chemical Technology Division, Argonne National Laboratory, Argonne, Illinois (USA)
2012-01-01
This data package presents atmospheric CH4 concentration and 13C isotopic abundance data derived from air samples collected over the period 1978-1989 at globally distributed clean-air sites. The data set comprises 201 records, 166 from the Northern Hemisphere and 35 from the Southern Hemisphere. The air samples were collected mostly in rural or marine locations remote from large sources of CH4 and are considered representative of tropospheric background conditions. The air samples were processed by isolation of CH4 from air and conversion to CO2 for isotopic analysis by isotope ratio mass spectrometry. These data represent one of the earliest records of 13C isotopic yy!measurements for atmospheric methane and have been used to refine estimates of CH4 emissions, calculate annual growth rates of emissions from changing sources, and provide evidence for changes in the rate of atmospheric removal of CH4. The data records consist of sample collection date; number of samples combined for analysis; sampling location; analysis date; CH4 concentration; 13C isotopic abundance; and flag codes to indicate outliers, repeated analyses, and other information.
NASA Astrophysics Data System (ADS)
Wong, Fiona; Alegria, Henry A.; Jantunen, Liisa M.; Bidleman, Terry F.; Salvador-Figueroa, Miguel; Gold-Bouchot, Gerardo; Ceja-Moreno, Victor; Waliszewski, Stefan M.; Infanzon, Raul
The extent of organochlorine pesticides (OCs) contamination in southern Mexico was investigated in this study. Biweekly air samplings were carried out in two sites in the state of Chiapas (during 2002-2003), and one in each state of Veracruz and Tabasco (during 2003-2004). Corresponding to the air sampling locations, soil samples were also collected to gauge the soil-air exchange of OCs in the region. ∑DDTs in soils ranged from 0.057 to 360 ng g -1 whereas those in air ranged from 240 to 2400 pg m -3. DDT and metabolite DDE were expressed as fractional values, FDDTe = p, p'-DDT/( p, p'-DDT + p, p'-DDE) and FDDTo = p,p'-DDT/( p,p'-DDT + o,p'-DDT). FDDTe in soils ranged from 0.30 to 0.69 while those in air ranged from 0.45 to 0.84. FDDTe in air at a farm in Chiapas (0.84) was closer to that of technical DDT (0.95) which is suggestive of fresh DDT input. Enantiomer fractions (EF) of o,p'-DDT in air were racemic at all locations (0.500-0.504). However, nonracemic o,p'-DDT was seen in the soils (EFs = 0.456-0.647). Fugacities of OCs in soil ( fs) and air ( fa) were calculated, and the fugacity fraction, ff = fs/( fs + fa) of DDTs ranged from 0.013 to 0.97 which indicated a mix of net deposition ( ff < 0.5) and volatilization ( ff > 0.5) from soil among the sites. It is suggested that DDTs in Mexico air are due to a combination of ongoing regional usage and re-emission of old DDT residues from soils. Total toxaphene in soils ranged from 0.066 to 69 ng g -1 while levels in air ranged from 6.2 to 230 pg m -3. Chromatographic profiles of toxaphenes in both air and soil showed depletion of Parlar congeners 39 and 42. Fugacity fractions of toxaphene were within the equilibrium range or above the upper equilibrium threshold boundary. These findings suggested that soil emission of old residues is the main source of toxaphenes to the atmosphere. Results from this study provide baseline data for establishing a long-term OC monitoring program in Mexico.
A new device for dynamic sampling of radon in air
NASA Astrophysics Data System (ADS)
Lozano, J. C.; Escobar, V. Gómez; Tomé, F. Vera
2000-08-01
A new system is proposed for the active sampling of radon in air, based on the well-known property of activated charcoal to retain radon. Two identical carbon-activated cartridges arranged in series remove the radon from the air being sampled. The air passes first through a desiccant cell and then the carbon cartridges for short sampling times using a low-flow pump. The alpha activity for each cartridge is determined by a liquid scintillation counting system. The cartridge is placed in a holder into a vial that also contains the appropriate amount of scintillation cocktail, in a way that avoids direct contact between cocktail and charcoal. Once dynamic equilibrium between the phases has been reached, the vials can be counted. Optimum sampling conditions concerning flow rates and sampling times are determined. Using those conditions, the method was applied to environmental samples, straightforwardly providing good results for very different levels of activity.
30 CFR 71.701 - Sampling; general requirements.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Sampling; general requirements. 71.701 Section... MINES Airborne Contaminants § 71.701 Sampling; general requirements. (a) Air samples will be taken by... operator shall conduct any additional air sampling tests and analyses as the Secretary may from time to...
30 CFR 71.701 - Sampling; general requirements.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Sampling; general requirements. 71.701 Section... MINES Airborne Contaminants § 71.701 Sampling; general requirements. (a) Air samples will be taken by... operator shall conduct any additional air sampling tests and analyses as the Secretary may from time to...
Microbial quality of water in dental unit waterlines.
Nikaeen, Mahnaz; Hatamzadeh, Maryam; Sabzevari, Zohre; Zareh, Omolbanin
2009-09-01
Dental unit waterlines (DUWLs) are ideal environment for development of microbial biofilms. Microbial contamination of water in DUWLs is thought to be the result of biofilm formation as it could serves as a haven for pathogens. The aim of this study was to assess microbial quality of water in dental unit waterlines of dental units located at the dental school of Isfahan University of Medical Sciences. Water samples were collected from air/water syringe and high-speed handpiece. Generally, 100-200 ml water samples were collected aseptically in sterile containers with sodium thiosulfate at the beginning of the day after a 2 minute purge. Samples were transferred to the laboratory in insulated box with cooling packs and examined for total viable heterotrophic bacteria and fungi. The heterotrophic plate count levels were significantly exceeded the American Dental Association recommendations for DUWL water quality (< 200 CFU/ml), in both air/water syringe (84%, CFU/ml: 500-20000) and high-speed handpiece (96%, CFU/ml: 710-36800) samples. However, there was no significant difference between the level of contamination in the air/water syringe and high-speed handpiece. Fungi were found in 28% and 36% of air/water syringe and high-speed handpiece samples, respectively; and filamentous fungi were the most frequently isolated fungi. DUWLs should be subjected to routine microbial monitoring and to a decontamination protocol in order to minimize the risk of exposure to potential pathogens from dental units.
Airborne concentrations of volatile organic compounds in neonatal incubators.
Prazad, P; Cortes, D R; Puppala, B L; Donovan, R; Kumar, S; Gulati, A
2008-08-01
To identify and quantify airborne volatile organic compounds (VOCs) inside neonatal incubators during various modes of operation within the neonatal intensive care unit (NICU) environment. Air samples were taken from 10 unoccupied incubators in four operational settings along with ambient air samples using air sampling canisters. The samples were analyzed following EPA TO-15 using a Tekmar AutoCan interfaced to Agilent 6890 Gas Chromatograph with a 5973 Mass Spectrometer calibrated for 60 EPA TO-15 method target compounds. Non-target compounds were tentatively identified using mass spectral interpretation and with a mass spectral library created by National Institute for Standards and Technology. Two non-target compounds, 2-heptanone and n-butyl acetate, were found at elevated concentrations inside the incubators compared with ambient room air samples. Increase in temperature and addition of humidity produced further increased concentrations of these compounds. Their identities were verified by mass spectra and relative retention times using authentic standards. They were quantified using vinyl acetate and 2-hexanone as surrogate standards. The emission pattern of these two compounds and background measurements indicate that they originate inside the incubator. There is evidence that exposure to some VOCs may adversely impact the fetal and developing infants' health. Currently, as there is no definitive information available on the effects of acute or chronic low-level exposure to these compounds in neonates, future studies evaluating the health effects of neonatal exposure to these VOCs are needed.
Tang, Chia Hsi; Garshick, Eric; Grady, Stephanie; Coull, Brent; Schwartz, Joel; Koutrakis, Petros
2018-01-01
The effects of indoor air pollution on human health have drawn increasing attention among the scientific community as individuals spend most of their time indoors. However, indoor air sampling is labor-intensive and costly, which limits the ability to study the adverse health effects related to indoor air pollutants. To overcome this challenge, many researchers have attempted to predict indoor exposures based on outdoor pollutant concentrations, home characteristics, and weather parameters. Typically, these models require knowledge of the infiltration factor, which indicates the fraction of ambient particles that penetrates indoors. For estimating indoor fine particulate matter (PM2.5) exposure, a common approach is to use the indoor-to-outdoor sulfur ratio (Sindoor/Soutdoor) as a proxy of the infiltration factor. The objective of this study was to develop a robust model that estimates Sindoor/Soutdoor for individual households that can be incorporated into models to predict indoor PM2.5 and black carbon (BC) concentrations. Overall, our model adequately estimated Sindoor/Soutdoor with an out-of-sample by home-season R2 of 0.89. Estimated Sindoor/Soutdoor reflected behaviors that influence particle infiltration, including window opening, use of forced air heating, and air purifier. Sulfur ratio-adjusted models predicted indoor PM2.5 and BC with high precision, with out-of-sample R2 values of 0.79 and 0.76, respectively. PMID:29064481
Dėdelė, Audrius; Miškinytė, Auksė
2016-09-01
Indoor air pollution significantly influences personal exposure to air pollution and increases health risks. Nitrogen dioxide (NO2) is one of the major air pollutants, and therefore it is important to properly determine indoor concentration of this pollutant considering the fact that people spend most of their time inside. The aim of this study was to assess indoor and outdoor concentration of NO2 during each season; for this purpose, passive sampling was applied. We analyzed homes with gas and electric stoves to determine and compare the concentrations of NO2 in kitchen, living room, and bedroom microenvironments (MEs). The accuracy of passive sampling was evaluated by comparing the sampling results with the data from air quality monitoring stations. The highest indoor concentration of NO2 was observed in kitchen ME during the winter period, the median concentration being 28.4 μg m(-3). Indoor NO2 levels in homes with gas stoves were higher than outdoor levels during all seasons. The concentration of NO2 was by 2.5 times higher in kitchen MEs with gas stoves than with electric stoves. This study showed that the concentration of NO2 in indoor MEs mainly depended on the stove type used in the kitchen. Homes with gas stoves had significantly higher levels of NO2 in all indoor MEs compared with homes where electric stoves were used.
Silva, Zelinda Isabel; Rebelo, Maria Helena; Silva, Manuela Manso; Alves, Ana Martins; Cabral, Maria da Conceição; Almeida, Ana Cristina; Aguiar, Fátima Rôxo; de Oliveira, Anabela Lopes; Nogueira, Ana Cruz; Pinhal, Hermínia Rodrigues; Aguiar, Pedro Manuel; Cardoso, Ana Sofia
2012-01-01
Characterization of water quality from indoor swimming pools, using chorine-based disinfection techniques, was performed during a 6-mo period to study the occurrence, distribution, and concentration factors of trihalomethanes (THM). Several parameters such as levels of water THM, water and air chloroform, water bromodichloromethane (BDCM), water dibromochloromethane (DBCM), water bromoform (BF), free residual chlorine (FrCl), pH, water and air temperature, and permanganate water oxidizability (PWO) were determined in each pool during that period. Chloroform (CF(W)) was the THM detected at higher concentrations in all pools, followed by BDCM, DBCM, and BF detected at 99, 34, and 6% of the samples, respectively. Water THM concentrations ranged from 10.1 to 155 μg/L, with 6.5% of the samples presenting values above 100 μg/L (parametric value established in Portuguese law DL 306/2007). In this study, air chloroform (CF(Air)) concentrations ranged from 45 to 373 μg/m³ with 24% of the samples presenting values above 136 μg/m³ (considered high exposure value). Several significant correlations were observed between total THM and other parameters, namely, CF(W), CF(Air), FrCl, water temperature (T(W)), and PWO. These correlations indicate that FrCl, T(W) and PWO are parameters that influence THM formation. The exposure criterion established for water THM enabled the inclusion of 67% of Lisbon pools in the high exposure group, which reinforces the need for an improvement in pool water quality.
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