Formation of dioxins from incineration of foods found in domestic garbage.

PubMed

Katami, Takeo; Yasuhara, Akio; Shibamoto, Takayuki

2004-02-15

There has been great concern about the large amounts of garbage produced by domestic households in the modern world. One of the major sources of dioxins (PCDDs, PCDFs, and coplanar PCBs) in the environment is the combustion of domestic waste materials. Exhaust gases from an incinerator, in which mixtures of 67 food items--including fruits, vegetables, pasta, seafoods, meats, and processed foods and seasoned foods--were analyzed for dioxins. Gases collected at the chimney port (9.15 ng/g) contained less total dioxins than those collected at the chamber port (29.1 ng/g). The levels of Cl1-Cl6-PCDDs and Cl1-Cl5-PCDFs were much lower in the gas collected at the chimney port than in the gas collected at the chamber port. The levels of Cl7-Cl8-PCDDs and Cl6-Cl8-PCDFs were higher in the gas collected at the chimney port than in the gas collected at the chamber port. A total of Cl4-Cl8-PCDDs (1.84-3.04 ng/g) comprised over 80% of the total PCDDs formed (2.24-4.00 ng/g). Total PCDFs (16.2-22.6 ng/g) comprised 78-86% of the total dioxins formed (18.9-29.1 ng/g). The PCDFs formed in the greatest amounts were M1CDFs (9.68-10.7 ng/g). Mixtures of commonly consumed food items produced ppb levels of total dioxins in exhaust gases upon combustion, suggesting that incineration of domestic food wastes is one of the sources of dioxins in the environment. A mixture containing some seasoned foods, such as mayonnaise spread on bread, produced more dioxins (29.1 ng/g) than a mixture without seasoned foods did (18.9 ng/g).

Polychlorinated dibenzo-p-dioxins and dibenzofurans: Correlation between in vivo structure-activity relationships (SARs)

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

Safe, S.; Mason, G.; Keys, B.

1986-01-01

Polychlorinated dibenzofurans (PCDFs) and dibenzo-p-dioxins (PCDDs) elicit a number of common biologic and toxic responses which are triggered by their initial binding to a cytosolic receptor protein. These effects include the induction of several cytochrome P-448 dependent monoxygenases (eg, aryl hydrocarbon hydroxylase, AHH), body weight loss and thymic atrophy. The dose-response effects of selected PCDFs on AHH induction in rat hepatoma H-4-II E cells and cytosolic receptor binding affinities have been determined. The results of these in vivo and in vitro studies demonstrate the remarkable effects of structure on the activity of PCDFs. A systematic study of each of themore » four different position for chlorine substitution in the dibenzofuran ring system showed that the toxic and biologic potencies of these compounds varied with respect to differential chlorine substitution at all four position, i.e. C-3(7) > C-2(8) >C-4(6) > C-1(9). In vitro SARs for PCDDs confirmed the importance of the lateral CI substituents and also showed that 1,2(or 6,7-) substituted PCDDs were more active than the corresponding 1,3-dichloro analogs. In addition, there were significant decreases in activity with increasing non-lateral CI substitution. The SARs for PCDFs were different from the PCDDs and this was directly related to the asymmetric structure of the former group of compounds.« less

An automated HPLC method for the fractionation of polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans in fish tissue on a porous graphitic carbon column

USGS Publications Warehouse

Echols, Kathy R.; Gale, Robert W.; Tillitt, Donald E.; Schwartz, Ted R.; O'Laughlin, Jerome

1997-01-01

The Ah (aryl-hydrocarbon) hydroxylase-receptor active polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were fractionated by an automated high-performance liquid chromatography (HPLC) system using the Hypercarb™ porous graphitic carbon (PGC) column. This commercially available column was used to fractionate the di-, mono-, and non-ortho PCBs into three fractions for gas chromatography (GC)/electron capture detection analysis, and a fourth fraction containing the PCDDs/PCDFs for GC/mass spectrometry analysis. The recoveries of the PCBs ranged from 68 to 96%, and recoveries of the PCDDs/PCDFs ranged from 74 to 123%. The PGC column has the advantage of faster separations (110 min versus 446 min) and less solvent use (275 ml versus 1,100 ml) compared with automated fractionation of these compounds on activated carbon (PX-21), while still affording good separation of the classes. The PGC column may have an advantage over the pyrenyl-based HPLC method because it has a greater loading capacity (400 μg total PCBs versus 250 μg). Overall, the PGC is a standard column that provides reproducible fractionation of PCDD/PCDFs and PCBs for analytical measurement in environmental samples.

ON-ROAD EMISSIONS OF PCDDS AND PCDFS FROM HEAVY DUTY DIESEL VEHICLES

EPA Science Inventory

This work characterized emission factors, homologue profiles, and isomer patterns of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) from on-road sampling of three heavy duty diesel vehicles (HDDVS) under various conditions of city and highway drivi...

Dibenzo-p-dioxins in the environment from ceramics and pottery produced from ball clay mined in the United States

NASA Technical Reports Server (NTRS)

Ferrario, Joseph; Byrne, Christian

2002-01-01

Processed ball clay samples used in the production of ceramics and samples of the ceramic products were collected and analyzed for the presence and concentration of the 2,3,7,8-Cl substituted polychlorinated dibenzo-p-dioxins and -furans (PCDDs/PCDFs). The processed ball clay had average PCDD concentrations of 3.2 ng/g toxic equivalents, a congener profile, and isomer distribution consistent with those found previously in raw ball clay. The PCDF concentrations were below the average limit of detection (LOD) of 0.5 pg/g. The final fired ceramic products were found to be free of PCDDs/PCDFs at the LODs. A consideration of the conditions involved in the firing process suggests that the PCDDs, if not destroyed, may be released to the atmosphere and could represent an as yet unidentified source of dioxins to the environment. In addition, the PCDDs in clay dust generated during manufacturing operations may represent a potential occupational exposure.

Dibenzo-p-dioxins in the environment from ceramics and pottery produced from ball clay mined in the United States.

PubMed

Ferrario, Joseph; Byrne, Christian

2002-03-01

Processed ball clay samples used in the production of ceramics and samples of the ceramic products were collected and analyzed for the presence and concentration of the 2,3,7,8-Cl substituted polychlorinated dibenzo-p-dioxins and -furans (PCDDs/PCDFs). The processed ball clay had average PCDD concentrations of 3.2 ng/g toxic equivalents, a congener profile, and isomer distribution consistent with those found previously in raw ball clay. The PCDF concentrations were below the average limit of detection (LOD) of 0.5 pg/g. The final fired ceramic products were found to be free of PCDDs/PCDFs at the LODs. A consideration of the conditions involved in the firing process suggests that the PCDDs, if not destroyed, may be released to the atmosphere and could represent an as yet unidentified source of dioxins to the environment. In addition, the PCDDs in clay dust generated during manufacturing operations may represent a potential occupational exposure.

A General Model of Dioxin Contamination in Breast Milk: Results from a Study on 94 Women from the Caserta and Naples Areas in Italy

PubMed Central

Rivezzi, Gaetano; Piscitelli, Prisco; Scortichini, Giampiero; Giovannini, Armando; Diletti, Gianfranco; Migliorati, Giacomo; Ceci, Roberta; Rivezzi, Giulia; Cirasino, Lorenzo; Carideo, Pietro; Black, Dennis M.; Garzillo, Carmine; Giani, Umberto

2013-01-01

Background: The Caserta and Naples areas in Campania Region experience heavy environmental contamination due to illegal waste disposal and burns, thus representing a valuable setting to develop a general model of human contamination with dioxins (PCDDs-PCDFs) and dioxin-like-PCBs (dl-PCBs). Methods: 94 breastfeeding women (aged 19–32 years; mean age 27.9 ± 3.0) were recruited to determine concentrations of PCDDs-PCDFs and dl-PCBs in their milk. Individual milk samples were collected and analyzed according to standard international procedures. A generalized linear model was used to test potential predictors of pollutant concentration in breast milk: age, exposure to waste fires, cigarette smoking, diet, and residence in high/low risk area (defined at high/low environmental pressure by a specific 2007 WHO report). A Structural Equation Model (SEM) analysis was carried out by taking into account PCDDs-PCDFs and dl-PCBs as endogenous variables and age, waste fires, risk area and smoking as exogenous variables. Results: All milk samples were contaminated by PCDDs-PCDFs (8.6 pg WHO-TEQ/98g fat ± 2.7; range 3.8–19) and dl-PCBs (8.0 pg WHO-TEQ/98g fat ± 3.7; range 2.5–24), with their concentrations being associated with age and exposure to waste fires (p < 0.01). Exposure to fires resulted in larger increases of dioxins concentrations in people living in low risk areas than those from high risk areas (p < 0.01). Conclusions: A diffuse human exposure to persistent organic pollutants was observed in the Caserta and Naples areas. Dioxins concentration in women living in areas classified at low environmental pressure in 2007 WHO report was significantly influenced by exposure to burns. PMID:24217180

Comparison of the contributions of polychlorinated dibenzo-p-dioxins and dibenzofurans and other unintentionally produced persistent organic pollutants to the total toxic equivalents in air of steel plant areas.

PubMed

Li, Sumei; Liu, Guorui; Zheng, Minghui; Liu, Wenbin; Wang, Mei; Xiao, Ke; Li, Changliang; Wang, Yiwen

2015-05-01

The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and the "dioxin-like" (dl) compounds polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), polybrominated dibenzo-p-dioxins (PBDDs), and dibenzofurans (PBDFs), were determined in the air samples collected from six steel plants. The toxic equivalent (TEQ) concentrations of the PCDDs, PCDFs, dl-PCBs, dl-PCNs, PBDDs, and PBDFs in the air were 0.01-0.19 pg WHO-TEQ Nm(-3), 0.01-0.69 pg WHO-TEQN m(-3), 0.001-0.089 pg WHO-TEQ Nm(-3), 0.002-0.011 pg TEQ Nm(-3), 0.004-0.02 pg TEQ Nm(-3), and 0.02-0.12 pg TEQ Nm(-3), respectively. The PCNs were the most abundant compounds (by mass concentration), contributing about 87% of the total mass concentrations of the analytes that were found in the air of the steel plant areas. The PCDFs contributed about 47% of the total TEQs, following by the PBDFs (28%) and the PCDDs (18%). The dioxin-like compounds together contributed up to 40% of the total TEQs, so their contributions to the toxic effects that could be caused by exposure to the air of the steel plant areas were significant. The congener profiles in the air were similar to the congener profiles that were found in stack gas emissions, indicating that the steelmaking plants were possible sources of the PCDDs, PCDFs, and dioxin-like compounds that were found in the air of the steel plant areas. Copyright © 2015 Elsevier Ltd. All rights reserved.

SW-846 Test Method 4025: Screening for Polychlorinated Dibenzodioxins and Polychlorinated Dibenzofurans (PCDD/PCDFs) by Immunoassay

EPA Pesticide Factsheets

a procedure for the analysis of (PCDDs/PCDFs) in soil at 500 ppt (pg/g) using a simple onestep liquid phase oxidative cleanup or, at mid to low ppt levels, using a two step coupled column cleanup (oxidation and activated carbon binding)

Determination of PCDF/PCDD in sludges from a drinking water treatment plant influence of chlorination treatment.

PubMed

Rivera, J; Eljarrat, E; Espadaler, I; Martrat, M G; Caixach, J

1997-01-01

A preliminary study to assess the origin and evolution of polichlorodibenzofurans (PCDFs) and polichlorodibenzo-p-dioxins (PCDDs) in a drinking water treatment plant (DWTP) was undertaken. Samples of coagulation sludges and exhausted granular activated carbon (GAC) were collected from a DWTP. Owing to the similar congener profiles obtained from sludges and GAC, a subsequent study of chlorination influence was carried out. Sludge samples from a treatment with and without the chlorination step were analysed. A complementary study of the PCB content was made. The results obtained did not reveal a marked influence of chlorination in the formation of PCDFs/PCDDs.

Evaluation of 2,3,7,8 specific congener and toxic potency of persistent polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in cetaceans from the Mediterranean Sea, Italy

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

Jimenez, B.; Gonzalez, M.J.; Jimenez, O.

2000-03-01

The present study investigates individual 2,3,7,8-substituted polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) concentrations in cetaceans and assesses the PCDD and PCDF contributions to the total TCDD equivalent concentration. Liver samples of a variety of cetaceans species found stranded along the Italian coasts during the period of 1987--1992 were analyzed for PCDDs and PCDFs. The main aims were to scrutinize levels and patterns of PCDDs and PCDFs for the first time in cetaceans from the Mediterranean Sea and to estimate whether chlorinated compounds mentioned are implicated in the exceptionally high mortality of dolphins that occurred in the Mediterranean sea duringmore » 1990--1992. PCDD and PCDF profiles were dominated by congeners OCCD and OCDF. The new toxic equivalency factors recommended by WHO in 1997 were used for calculation of dioxin-like toxicity. On the basis of their previous study of PCBs, the overall TEQ calculated from the 2,3,7,8-substituted PCDDs and PCDFs do not contribute as much dioxin-like toxicity as PCBs.« less

Basic alumina flash chromatographic separation of bulk ortho-PCBs from on-ortho-PCBs, PBDEs, PCDFs, PCDDs, PCDTs, OCPs, and PCTs

USGS Publications Warehouse

Peterman, Paul H.; Orazio, Carl E.; Echols, Kathy R.

2006-01-01

Comprising nearly 100 congeners in environmental samples, PCBs are often still prevalent in concentrations exceeding 1 μg/g. To effectively measure PCBs, they are isolated as a group from other persistent organic pollutants using silica gel, Florisil, or alumina column chromatography for analysis by GC/MS or dual capillary column GC/ECD. When organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) are also targeted, PCBs are often split into two chromatographic eluates. In contrast to the major ortho-substituted PCB congeners, much lower concentrations occur for congeners of polychlorinated- dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), dibenzothiophenes (PCDTs), naphthalenes (PCNs), and dioxin-like non-ortho-PCBs1 . Such co-planar compounds are usually separated from the bulk PCBs using a carbon LC2 or reusable porous graphitic carbon HPLC column3 eluted forward (o-PCBs, mono-o-PCBs, then non-o-PCBs) before reversal with toluene (PCDFs and PCDDs) and additional separation with basic alumina to remove PCNs, polychlorinated diphenyl ethers (PCDEs), and residual lipid for PCDF/PCDD GC/HRMS analysis. Recently, smaller particle-size normal phase adsorbents including active basic alumina have become available along with custom-made glass columns for use in low pressure flash chromatography. With low gas pressure (< 1-2 bar) and particles 32-63 μm, flash chromatography is a rapid, inexpensive technique with enhanced resolution compared to gravity column chromatography4 . However, few environmental researchers use the technique, but basic alumina is in the automated PowerPrep LC system for PCDFs, PCDDs, PCBs and PBDEs5 . A flash LC column is quickly dry-packed, gives improved flow performance, and has sufficient resistance to gravity flow without a shutoff valve. Contamination from lab air, dust, and sample carryover is minimized by using high purity nitrogen, much smaller eluate volumes and blown down in tubes with high purity nitrogen. The disposable adsorbent is used only once with an inert, nonleachable, reusable and cleanable glass column with glass joints and disposable glass fiber. We evaluated basic alumina flash chromatography initially for PCBs, because Loos et al.6 had separated 13 selected o-PCB congeners from three non-o-PCBs (77, 126, and 169) and then from PCDFs and PCDDs with eluants of 150- 200 mL each from a large 25-g basic alumina (Super 1 active) column. Because the elution properties of other PCB congeners were unknown in addition to some PBDEs, PCDTs, and other compounds, we chose to evaluate basic alumina flash chromatography comprehensively. We optimized the separation of all bulk o-PCBs from all non-o-PCBs, tested other pollutants (PBDEs, PCDTs, PCDFs and PCDDs) under similar elution conditions, and finally applied the chromatographic technique to samples known or suspected to contain complex mixtures of these.

[Dioxins in agricultural soil of Poland].

PubMed

Wyrzykowska, Barbara; Falandysz, Jerzy; Hanari, Nobuyashi; Yamashita, Nobuyoshi

2006-01-01

Total PCDDs concentration ranged from 6.8 to 41 pg g d.w. and for PCDFs from 3.9 to 19 pg/g d.w. with total toxic equivalency within a range 0.023-5.9 pg TEQ/g d.w. A somewhat elevated concentrations of PCDDs and PCDFs were found in the samples collected from the south of Poland in the vicinity of highly industrialized regions known for former extensive mining industry of hard coal and metallurgy, as well as for regions with high rates of urbanization in central Poland and in the vicinity of the western border of the country. Nevertheless, if consider homologue specific pattern of PCDDs and PCDFs no major differences were noted between spatially scattered sampling sites. In all samples highly chlorinated PCDDs/DFs dominated (12345678-OcCDD, 1234678-HpCDD, 12346789-OcCDF, 1234789-HpCDF, 1234678-HpCDF were found in all investigated soils). Their similar pattern can suggest that formation of these chemicals occur in similar conditions. Energy production and fossil fuel co-fired power boilers, chemical industry, metallurgical industry are probably the main sources in industrial regions, however heating of houses by small stoves and hard coal with added household wastes, and former use of agrochemical formulations consisting byimpurities of PCDD/F may also play important role at rural sites. The particularly elevated concentrations of OcCDF in some samples might be connected to the former production and use of highly chlorinated polychlorinated biphenyl formulation--Chlorofen.

DEVELOPMENT OF A REFINED DATABASE OF RELATIVE POTENCY ESTIMATES TO FACILITATE BETTER CHARACTERIZATION OF VARIABILITY AND UNCERTAINTY IN THE CURRENT MAMMALIAN TEFS FOR PCDDS, PCDFS, AND DIOXIN-LIKE PCBS

EPA Science Inventory

The toxic equivalency factor (TEF) approach has been widely accepted as the most feasible and plausible method presently available for evaluating potential health risks associated with exposure to mixtures of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofuran...

Declining Dioxin concentrations in the Rhone River, France, attest to the effectiveness of emissions controls

USGS Publications Warehouse

Van Metre, Peter C.; Babut, Marc; Mourier, Brice; Mahler, Barbara J.; Roux, Gwenaelle; Desmet, Marc

2015-01-01

Emission-control policies have been implemented in Europe and North America since the 1990s for polychlorodibenzodioxins (PCDDs) and furans (PCDFs). To assess the effect of these policies on temporal trends and spatial patterns for these compounds in a large European river system, sediment cores were collected in seven depositional areas along the Rhone River in France, dated, and analyzed for PCDDs and PCDFs. Results show concentrations increase in the downstream direction and have decreased temporally at all sites during the last two decades, with an average decrease of 83% from 1992 to 2010. The time for a 50% decrease in concentrations (t1/2) averaged 6.9 ± 2.6 and 9.1 ± 2.9 years for the sum of measured PCDDs and PCDFs, respectively. Congener patterns are similar among cores and indicate dominance of regional atmospheric deposition and possibly weathered local sources. Local sources are clearly indicated at the most downstream site, where concentrations of the most toxic dioxin, TCDD, are about 2 orders of magnitude higher than at the other six sites. The relatively steep downward trends attest to the effects of the dioxin emissions reduction policy in Europe and suggest that risks posed to aquatic life in the Rhone River basin from dioxins and furans have been greatly reduced.

Isomer pattern and elimination of dioxins in workers exposed at a municipal waste incineration plant

PubMed Central

YAMAMOTO, Kenya; KUDO, Mitsuhiro; ARITO, Heihachiro; OGAWA, Yasutaka; TAKATA, Tsutomu

2015-01-01

The aim of this study was to clarify patterns of serum concentrations of dioxins in the employees of a waste incineration plant and to estimate elimination rates and half-lives of serum dioxin isomers, and the maximum serum concentrations of dioxin isomers at the time of plant shutdown. Sixteen subjects participating 3 times or more in annual health examinations during an 8-yr period from 2000 to 2007 were recruited for this study. Serum concentrations of dioxins expressed as TEQ/g lipid decreased gradually after plant shutdown with the highest decrease observed in polychlorinated dibenzofurans (PCDFs) followed by polychlorinated deibenzo-p-dioxins (PCDDs) and then coplanar PCBs. The serum toxic equivalency (TEQ) concentrations of PCDF and PCDD congeners in the employees were higher than those in the general population survey by the Ministry of the Environment, Japan, whereas the serum concentrations of coplanar PCBs were similar to those in the general population. The estimated half-lives and elimination rates of PCDDs and PCDFs in the highly exposed workers increased compared with the moderately exposed workers. The estimated geometric mean serum concentrations of PCDDs, PCDFs and total dioxins at the time of plant shutdown were 35, 53 and 107 pg TEQ/g lipid, respectively. PMID:26118856

A cross-sectional analysis of dioxins and health effects in municipal and private waste incinerator workers in Japan

PubMed Central

YAMAMOTO, Kenya; KUDO, Mitsuhiro; ARITO, Heihachiro; OGAWA, Yasutaka; TAKATA, Tsutomu

2015-01-01

This cross-sectional study was intended to examine health effects of 678 male workers employed during an 8-yr period from 2000 to 2007 at 36 municipal and private waste incineration plants in Japan. Blood samples were obtained for analysis of concentrations of dioxins including coplanar polychlorinated biphenyls (coplanar PCBs) and evaluation of health effects. Health effects including diabetes were surveyed via a physician’s interview or clinical data from blood samples. There was a certain difference in serum concentrations of polychlorinated dibenzofurans (PCDFs) between the incinerator workers and Japanese general population, although no differences in the concentrations of total dioxins or polychlorinated dibenzo-p-dioxins (PCDDs) were found between the two groups. A few positive correlations between serum levels of PCDDs and PCDFs and the results of laboratory and physiological tests were found, but coplanar PCBs showed significant relations with 14 parameters of the tests. The background serum levels of PCDDs, PCDFs and total dioxins were significantly associated with the prevalence of diabetes. No essential differences in serum concentrations of total dioxins and in prevalence of diabetes between our subjects and the general population suggested that the incinerator workers were marginally exposed to dioxins in the workplace without any recognizable adverse health effects. PMID:26212412

Levels and congener profiles of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in sheep milk from an industrialised area of Sardinia, Italy.

PubMed

Storelli, M M; Scarano, C; Spanu, C; De Santis, E P L; Busco, V P; Storelli, A; Marcotrigiano, G O

2012-05-01

Concentrations of 7 polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs) and 22 polychlorinated biphenyls (PCBs), including 12 dioxin like-PCBs (non- and mono-ortho PCBs) were measured in 80 sheep milk samples from farms located in an industrialized area of Sardinia, Italy. PCDDs and PCDFs mean concentrations were 2.45 and 3.69 pgg(-1) fat basis, respectively. The mean dl-PCB concentration was 2.01 ngg(-1) fat basis, while cumulative ndl-PCB levels ranged from 1.02 to 20.42, with a mean of 4.92 ngg(-1) fat. The results expressed in pg WHO-TEQ/g fat showed that contamination level of milk was below the limit values for human consumption established by EC legislation. In the same way, all the investigated milk exhibited PCDD/Fs concentrations below EU action levels, while dl-PCBs concentrations exceeded the action level of 2.0 pg WHO-TEQ/g fat. These findings point to the need to continue to conduct general monitoring programmes, including also milk samples from areas not close to the contaminant-emitting industries, in order to better evaluate the impact of industrial activities on surrounding environment. Copyright © 2012 Elsevier Ltd. All rights reserved.

Occurrence of organochlorine contaminants (PCBs, PCDDs and PCDFs) and pathologic findings in loggerhead sea turtles, Caretta caretta, from the Adriatic Sea (Mediterranean Sea).

PubMed

Storelli, Maria M; Zizzo, Nicola

2014-02-15

Livers of 12 loggerhead sea turtles, Caretta caretta from the Eastern Mediterranean Sea (Adriatic Sea) were analyzed for the presence of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Pathological and microbiological studies were also carried out in order to provide a contribution to the knowledge of causes of Mediterranean turtle death. Boat-strike injuries, entanglement in derelict fishing nets and ingestion of hooks and monofilament lines are the causes of death most frequently observed. PCBs (average: 1,399 ng g(-1) fat basis) were the dominant chemicals, followed by PCDFs (average: 61 pg g(-1) fat basic) and PCDDs (average: 16 pg g(-1) fat basis). Hexachlorobiphenyl 153 accounted for the greatest proportion of the total PCBs, followed in order by PCB 138 and PCB 180 (14.1%). Mid-chlorinated, penta-through hepta-PCBs were among the top contributors to the sum of total PCBs, while the homolog pattern of PCCD/Fs was dominated by the tetra- to hexa-substituted congeners. In general the contamination level observed here was comparable with that reported in literature for specimens from different marine areas. Average TEQPCDD/Fs+Dl-PCBs concentration was 27.02 pg g(-1) wet weight (305.1 pg g(-1) lipid weight), with dioxin like-PCBs (93.4%) contributing much more to the total than PCDFs (3.9%) and PCDDs (2.7%). The appreciable concentration of TEQ would at first suggest that there are signs of potential threats to the health of these marine reptiles. Apart from PCBs, this is the first study documenting concentrations of PCDD/Fs in marine turtles from the Mediterranean Sea. Further investigations are urgently needed to characterize their contamination level for a better future protection and conservation of this endangered animal. Copyright © 2013 Elsevier B.V. All rights reserved.

Evaluation of planar halogenated and polycyclic aromatic hydrocarbons in estuarine sediments using ethoxyresorufin-O-deethylase induction of H4IIE cells

USGS Publications Warehouse

Gale, R.W.; Long, E.R.; Schwartz, T.R.; Tillitt, D.E.

2000-01-01

Polycyclic aromatic hydrocarbons (PAHs) and planar halogenated hydrocarbons (PHHs), including polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) were determined in fractionated sediment extracts from the Hudson-Raritan estuary and Newark Bay, New Jersey, USA, as part of a comprehensive risk assessment. Contributions of PCDDs/PCDFs, PCBs, and PAHs to the total toxic equivalents (TEQs) were measured using an H4IIE bioassay and calculated from instrumentally determined concentrations using international toxic equivalency factors. The H4IIE TEQs of whole and fractionated extracts were compared to calculated TEQs to investigate the applicability of the bioassay approach for evaluating 7-ethoxyresorufin-O-deethylease induction by PHHs and PAHs present together in complex mixtures. Although 2,3,7,8-tetrachlorodibenzo-p-dioxin contributed from 41 to 79% of the calculated TEQs from PCDDs/PCDFs and planar PCBs in all sediments sampled, the PAH-containing fractions accounted for >80% of the total TEQs determined either instrumentally or by bioassay. Calculated TEQs from PAHs, based on reported toxic equivalency factors for only seven PAHs, were severalfold greater than the bioassay-derived TEQs of PAH-only fractions of the sediment extracts. Significant correlations were observed between bioassay and instrumentally determined toxic equivalents in the more purified fractions but not in fractions only purified by size-exclusion or argentate chromatographies alone.

Development of a reference material for routine performance monitoring of methods measuring polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like polychlorinated biphenyls.

PubMed

Selliah, S S; Cussion, S; MacPherson, K A; Reiner, E J; Toner, D

2001-06-01

Matrix-matched environmental certified reference materials (CRMs) are one of the most useful tools to validate analytical methods, assess analytical laboratory performance and to assist in the resolution of data conflicts between laboratories. This paper describes the development of a lake sediment as a CRM for polychorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (DLPCBs). The presence of DLPCBs in the environment is of increased concern and analytical methods are being developed internationally for monitoring DLPCBs in the environment. This paper also reports the results of an international interlaboratory study involving thirty-five laboratories from seventeen countries, conducted to characterize and validate levels of a sediment reference material for PCDDs, PCDFs and DLPCBs.

The concentration and distribution of 2,3,7,8-dibenzo-p-dioxins/-furans in chickens

NASA Technical Reports Server (NTRS)

Ferrario, J.; Byrne, C.

2000-01-01

The concentrations of the 2,3,7,8-Cl substituted dibenzo-p-dioxins/-furans (PCDDs/PCDFs) were determined in the edible tissues of whole chicken fryers and compared with the values found in their abdominal fat. The values are presented both on a whole weight basis and on a lipid adjusted basis for each tissue. While there is a marked difference in the concentration of the 2,3,7,8-dibenzo-p-dioxins in the edible tissues expressed on a whole weight basis, the lipid-adjusted concentrations of the individual dioxins were not statistically different in the various tissues. This validates the use of lipid adjusted concentrations of 2,3,7,8-PCDDs/PCDFs in abdominal fat for the determination of the presence of these compounds in different tissues.

Characterization of Air Emissions from Open Burning and ...

EPA Pesticide Factsheets

Emissions from open burning (OB) and open detonation (OD) of military ordnance and static fires (SF) of rocket motors were sampled in fall, 2013 at the Dundurn Depot (Saskatchewan, Canada). Emission sampling was conducted with an aerostat-lofted instrument package termed the “Flyer” that was maneuvered into the downwind plumes. Forty-nine OB events, 94 OD events, and 16 SF on four propellants types (Triple base, 105 M1, 155 M4A2 white bag, and 155 M6 red bag), two smokes (HC grenade and red phosphorus), five explosive types (Trigran, C4, ANFO, ANFO+HC grenade, and ANFO+Flare), and two rocket motors types (CVR-7 and MK 58) resulted in emission factors for particulate matter (PM), carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), volatile organic compounds (VOCs), chlorine species (HCl, chloride, chlorate, perchlorate), polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/PCDFs) and PM-based metals. These data provide Canada and the United States with additional air emissions data to support health risk assessments and permitting for safe treatment of military ordnance by OB/OD/SF. In addition, the data will be used to conduct air dispersion modelling assessing the impact of treatment of various ordnance on the air quality, to support mandatory reporting requirements of the Canadian Environmental Protection Act (CEPA), the National Pollutant Release Inventory (NPRI), and to update the Canadian Ammunition Chemical Database.Result

IMMUNOCHEMICAL DETERMINATION OF DIOXINS IN SEDIMENT SAMPLES

EPA Science Inventory

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are considered highly toxic contaminants with the environmental monitoring of these compounds being of great importance. Immunoassay procedures such as the enzyme-linked immunosorbent assay (ELIS...

Polychlorinated biphenyls, polybrominated biphenyls, polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans

EPA Science Inventory

Polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) belong to a group of compounds that are structurally related and are biologically and environmentally persistent. These chemical...

Polychlorinated biphenyls, polybrominated biphenyls, polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans.

EPA Science Inventory

Polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) belong to a group of compounds that are structurally related and are environmentally and biologically persistent. These chemical...

Waste disposal technologies for polychlorinated biphenyls.

PubMed Central

Piver, W T; Lindstrom, F T

1985-01-01

Improper practices in the disposal of polychlorinated biphenyl (PCB) wastes by land burial, chemical means and incineration distribute these chemicals and related compounds such as polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzodioxins (PCDDs) throughout the environment. The complete range of methods for disposal that have been proposed and are in use are examined and analyzed, with emphasis given to the two most commonly used methods: land burial and incineration. The understanding of aquifer contamination caused by migration of PCBs from subsurface burial sites requires a description of the physical, chemical and biological processes governing transport in unsaturated and saturated soils. For this purpose, a model is developed and solved for different soil conditions and external driving functions. The model couples together the fundamental transport phenomena for heat, mass, and moisture flow within the soil. To rehabilitate a contaminated aquifer, contaminated groundwaters are withdrawn through drainage wells, PCBs are extracted with solvents or activated carbon and treated by chemical, photochemical or thermal methods. The chemical and photochemical methods are reviewed, but primary emphasis is devoted to the use of incineration as the preferred method of disposal. After discussing the formation of PCDFs and PCDDs during combustion from chloroaromatic, chloroaliphatic, as well as organic and inorganic chloride precursors, performance characteristics of different thermal destructors are presented and analyzed. To understand how this information can be used, basic design equations are developed from governing heat and mass balances that can be applied to the construction of incinerators capable of more than 99.99% destruction with minimal to nondetectable levels of PCDFs and PCDDs. PMID:3921358

ROLE OF SULFUR IN REDUCING PCDD AND PCDF FORMATION

EPA Science Inventory

Past research has suggested that the presence of sulfur (S) in municipal waste combustors (MWCs) can decrease downstream formation of chlorinated organic compounds, particularly polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Thus, co-firing a...

IMMUNOCHEMICAL DETERMINATION OF DIOXINS IN SEDIMENT AND SERUM SAMPLES

EPA Science Inventory

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are considered highly toxic contaminants and the environmental and biological monitoring of these compounds is of great concern. Immunoassays may be used as screening methods to satisfy the gro...

A PERFORMANCE HISTORY OF THE BASE CATALYZED DECOMPOSITION (BCD) PROCESS

EPA Science Inventory

Remediation of halogenated organic compounds--such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs)--poses a challenge because these compounds are resistant to microbial attack and to degradation by many com...

Emissions from Open burning of Used Agricultural Pesticide Containers

EPA Science Inventory

Emissions from simulated open burning of used agricultural pesticide containers were sampled for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs), polycyclic aromatic hydrocarbon compounds (PAHs), and particle matter (PM10 and PM2.5). Clean high density polyethyl...

PCDD AND PCDF EMISSIONS FROM SIMULATED SUGARCANE FIELD BURNING

EPA Science Inventory

The emissions from simulated sugarcane field burns were sampled and analyzed for polychlorinated dibenzodioxins and dibenzofurans (PCDDs and PCDFs). Sugarcane leaves from Hawaii and Florida were burned in a manner simulating the natural physical dimensions and biomass density fou...

PCDDs, PCDFs, PCBs, OC pesticides and mercury in fish and osprey eggs from Willamette River, Oregon (1993, 2001 and 2006) with calculated biomagnification factors

USGS Publications Warehouse

Henny, C.J.; Kaiser, J.L.; Grove, R.A.

2009-01-01

The osprey (Pandion haliaetus) population nesting along the main stem Willamette River and lower Santiam River was first studied to evaluate contaminants and reproductive rates in 1993 when 78 occupied nests were present. By 2001, the population increased to 234 occupied nests, a 13.7% annual rate of population increase. A sample egg was collected from each of a series of nests along the Upper River (river mile 55-187) in 1993, 2001 and 2006 to evaluate trends of persistent contaminants (organochlorine [OC] pesticides, polychlorinated biphenyls [PCBs], polychlorinated dibenzo-p-dioxins [PCDDs], and polychlorinated dibenzofurans [PCDFs]). Nearly all OC pesticide residues decreased significantly, e.g., p, p?-DDE (DDE) from 2,350 to 1,353 to 210 ??g/kg wet weight (ww). PCBs followed a similar pattern over time, e.g., ???PCBs 688 to 245 to 182 ??g/kg ww, while PCDDs and PCDFs showed a more precipitous decline (often 85-95%) between 1993 and 2001, with no egg analyses warranted in 2006. During 2001-2002, sample osprey eggs were also collected from nests at three Headwater Reservoirs and two lower reaches (Newberg Pool and Tidal Portland) of the Willamette River, as well as the lower portion of the Santiam River to evaluate spatial residue patterns. Significant differences were seldom detected among the different sampling areas for OC pesticides (probably due to small sample sizes), although higher concentrations were often seen in the lower reaches, e.g., DDE 901 ??g/kg ww (Headwater Reservoirs), 1,353 (Upper River), 1,384 (Newberg Pool) and 2,676 (Tidal Portland). PCB congener concentrations in eggs were usually higher in the Tidal Portland reach than at other locations and often significantly higher than at the Headwater Reservoirs or Upper River. Mercury (first analyzed in eggs in 2001), PCDDs and PCDFs were extremely low in 2001/2002 with no significant spatial patterns. Whole fish composite samples of largescale sucker (Catastomus macrocheilus) and northern pikeminnow (Ptychocheilus oregonensis), which account for about 90% of the biomass in the diet of this osprey population, were also collected from the Willamette River in 1993 and 2001 and analyzed for the same contaminants as osprey eggs. Contaminant residues in fish from the Upper River decreased between 1993 and 2001, paralleling findings for osprey eggs. Likewise, spatial patterns for fish residues paralleled findings for osprey eggs from the different reaches in 2001. A second empirical estimate of biomagnification factors (BMFs) from fish to osprey eggs for OC pesticides, PCBs, PCDDs and PCDFs (ww and lipid weight [lw] basis) was calculated based on residue data collected in 2001. The two independent BMF estimates (1993 and 2001) for each contaminant from the Upper River provide a measure of consistency, e.g., DDE (ww) 87 and 79, (lw) 103 and 112; ???PCBs (ww) 11 and 8.4, (lw) 13 and 12. Mercury did not biomagnify from fish to osprey eggs (BMF = 0.60). Legacy contaminants investigated had limited (perhaps only DDE), if any, effects on reproductive success of the increasing osprey population nesting along the Willamette River by 2001. ?? 2008 U.S. Government.

EFFECT OF SOOT AND COPPER COMBUSTOR DEPOSITS ON DIOXIN EMISSIONS

EPA Science Inventory

An experimental study was conducted to investigate the effects of residual soot and copper combustor deposits on the formation of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) during the combustion of a chlorinated waste. In a bench-scale set...

CONTROL OF DIOXIN, FURAN, AND MERCURY EMISSIONS FROM MUNICIPAL WASTE COMBUSTORS

EPA Science Inventory

There is a significant public and scientific concern over the potential risks of air pollution emissions from municipal waste combustors (MWCs). The primary pollutants of concern are polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs), and mercury (Hg). Depending on...

Levels and trends of organochlorines and brominated flame retardants in ivory gull eggs from the Canadian Arctic, 1976 to 2004.

PubMed

Braune, Birgit M; Mallory, Mark L; Grant Gilchrist, H; Letcher, Robert J; Drouillard, Ken G

2007-06-01

The ivory gull (Pagophila eburnea) is a circumpolar marine bird which has recently been listed as an endangered species in Canada. To determine whether contaminants may be playing a role in the population decline of this species, ivory gull eggs collected in 1976, 1987 and 2004 from Seymour Island in the Canadian Arctic were analyzed for organochlorines, polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and non-ortho PCBs. This study also provides the first account of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs) and polybrominated biphenyls (PBBs) in ivory gulls. The most quantitatively abundant legacy organochlorines found in the ivory gull eggs were p,p'-DDE, SigmaPCB and oxychlordane. Concentrations of the organochlorines analyzed either decreased or showed little change between 1976 and 2004. Concentrations of SigmaPCDD in ivory gull eggs were greater than SigmaPCDF, and the non-ortho PCBs (primarily PCB-126) contributed the largest fraction to the total TEQ value in all years sampled. Concentrations of PCDDs, PCDFs and SigmaTEQ decreased from 1976 to 2004. In contrast, concentrations of the PBDEs steadily increased between 1976 and 2004 driven primarily by increases in BDE-47. Although concentrations of the persistent chlorinated compounds (i.e. organochlorine pesticides, PCBs, PCDDs, PCDFs) reported in this study were below published toxicological threshold values for eggs of wild birds, we cannot rule out the possibility of synergistic/additive, sublethal effects. Very few studies have been carried out to evaluate the exposure-effect relationship of the persistent brominated compounds in avian species. Given the scarcity of information on toxicity threshold levels for PBBs and PBDEs in avian species, coupled with the trend toward increasing concentrations in ivory gulls, continued monitoring and further toxicological studies of these compounds are warranted.

Effects of Perinatal Dioxin Exposure on Development of Children during the First 3 Years of Life.

PubMed

Tai, Pham The; Nishijo, Muneko; Nghi, Tran Ngoc; Nakagawa, Hideaki; Van Luong, Hoang; Anh, Tran Hai; Nishijo, Hisao

2016-08-01

To investigate the longitudinal effects of perinatal exposure to dioxin on neurodevelopment and physical growth of a birth cohort during the first 3 years of life. A total of 217 mother-infant pairs living in a dioxin-contaminated area in Vietnam were followed up. Perinatal dioxin exposure of infants was estimated by the measurement of dioxin levels in breast milk of nursing mothers. Neurodevelopment of infants and children, including cognitive, language, and motor development, was determined at 4 months, 1 year, and 3 years of age. Physical growth, including weight, height, and head and abdominal circumferences, was measured at birth, 1 and 4 months, and 1 and 3 years of age. Multivariate mixed models were applied for analyzing repeated measures. In boys, composite motor and gross motor scores were decreased with increasing exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TetraCDD). The high toxic equivalent of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/PCDFs-TEQ) group showed a significant decrease in expressive communication score. In girls, there was no decreased score in any neurodevelopment aspects in high-exposure groups. All body size measures in boys were decreased in the high-exposure groups of 2,3,7,8-TetraCDD and PCDDs/PCDFs-TEQ. In girls, high 2,3,7,8-TetraCDD and PCDDs/PCDFs-TEQ exposure was associated with increased head and abdominal circumferences. Perinatal dioxin exposure affects physical growth and neurodevelopment of infants and children in the first 3 years of life in a sex-specific manner. Copyright © 2016 Elsevier Inc. All rights reserved.

Distribution and depth profiles of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and polychlorinated biphenyls in sediment collected from offshore waters of Central Vietnam.

PubMed

Tri, Tran Manh; Anh, Hoang Quoc; Tham, Trinh Thi; Van Quy, Tran; Long, Nguyen Quang; Nhung, Dao Thi; Nakamura, Masafumi; Nishida, Masayo; Maeda, Yasuaki; Van Boi, Luu; Minh, Tu Binh

2016-05-15

Concentrations of PCBs and OCPs were measured in 35 surface sediment samples collected from offshore waters of Central Vietnam. The mean concentrations of PCBs, HCHs, and DDTs in surface sediments were 86.5, 37.0, and 44.5pgg(-1), respectively. Additionally, nine PCDDs, eleven PCDFs, and twelve dl-PCBs were also examined in 19 sediment core samples collected from five locations. Concentration of PCDDs, PCDFs, and dl-PCBs ranged from 200 to 460, 0.39 to 2.9, and 1.6 to 22pgg(-1), respectively. OCDD was detected at the highest concentration, ranged from 100 to 300pgg(-1). Generally, the concentrations of PCDD/Fs at shallower depths were higher, meanwhile the depth profiles of dl-PCBs in sediment cores were different than the depth profiles of PCDD/Fs. The results suggest that the pollution of PCBs might be from many different sources leading to the variation between depths. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dioxins in beef samples from Mexico using a low resolution GC/MS screening method.

PubMed

Naccha, Lidia; Alanis, Guadalupe; Torres, Anabel; Abad, Esteban; Ábalos, Manuela; Rivera, Josep; Heyer, Lorenzo; Morales, Alberto; Waksman, Noemí

2010-01-01

Dioxins in beef were quantified by high resolution gas chromatography coupled to low-resolution mass spectrometry (GC/LRMS). The analyses were performed according to the minimum requirements described in the USEPA 1613 method with some minor modifications. Levels found in the samples were in the range 1.02-8.04 pg WHO-TEQ PCDDs/PCDFs g(-1) fat. For comparison purposes, the maximum level allowed by the European Union is 3 pg WHO-TEQ PCDDs/PCDFs g(-1) fat, and some of these samples surpassed the above-mentioned limit and can be considered as contaminated food. The results confirm that a preliminary screening of dioxins in beef can be performed by GC/LRMS. As far as we know, this is the first report of dioxins in beef in Mexico. After the appropriated tests, the applied methodology could be considered as an alternative screening method for the analysis of PCDD/Fs in other food products.

Results and evaluation of the first study of organochlorine contaminants (PCDDs, PCDFs, PCBs and DDTs), heavy metals and metalloids in birds from Baja California, México.

PubMed

Jiménez, Begoña; Rodríguez-Estrella, Ricardo; Merino, Rubén; Gómez, Gema; Rivera, Laura; José González, María; Abad, Esteban; Rivera, Josep

2005-01-01

Organochlorine compounds (OCs) including polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p-p'-DDE), heavy metals (Pb, Cd, Zn, Cu), and arsenic were measured in house sparrows (Passer domesticus) and common ground doves (Columbina passerina) from Baja California Sur, México. Concentrations of PCDD/Fs were low, with 21 pg/g for house sparrows, and 7.7 pg/g for common ground doves. Non-ortho-PCB concentrations in house sparrow and common ground doves were 58 and 254 pg/g, respectively, and are within the highest concentrations reported in species that are in the low levels of food webs. The major differences in organochlorine levels between species were found for ortho-PCBs and DDTs. ortho-PCB levels were higher in the seedeater species, whereas DDT levels were higher in the omnivorous species. Heavy metal levels were far below those associated with negative effects.

Dibenzo-p-dioxins and dibenzofurans in human breast milk collected in the area of Taranto (Southern Italy): first case study.

PubMed

Bianco, Giuliana; Zianni, Rosalia; Anzillotta, Giuseppe; Palma, Achille; Vitacco, Vincenzo; Scrano, Laura; Cataldi, Tommaso R I

2013-03-01

We report on the content of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in 15 breast milk samples of nursing women living in the city of Taranto (Southern, Italy) or nearby. Breast milk samples were collected over the 2008-2009 period and analyzed by gas chromatography coupled with high-resolution mass spectrometry (GC-HRMS) upon accelerated solvent extraction (ASE) using acetone/n-hexane mixture 1:1 (v/v). The method was validated demonstrating good performing features. Profiles of PCDD/PCDF congeners in breast milk samples exhibited a prevalence of PCDFs compared to PCDDs. Toxic equivalents (TEQs in picogram per gram fat) of four breast milk were far above the legal limit for human consumption of 3.0 pg/g; their estimated daily and weekly dietary intake were almost 5-20 and 10-40 times higher, respectively, than the tolerable intake values established by the World Health Organization.

Ambient air concentrations of PCDDs, PCDFs, coplanar PCBs, and PAHs at the Mississippi Sandhill Crane National Wildlife Refuge, Jackson County, Mississippi

USGS Publications Warehouse

White, D.H.; Hardy, J.W.

1994-01-01

Our objective was to determine the levels of selected airborne contaminants in ambient air at the Mississippi Sandhill Crane National Wildlife Refuge, Mississippi, that might be affecting the health of endangered cranes living there. Two high-volume air samplers were operated at separate locations on the Refuge during May?September 1991. The sampling media were micro-quartz filters in combination with polyurethane foam plugs. Composite bimonthly samples from each station were analyzed for polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), coplanar polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs). Overall, residue concentrations were low. The toxic PCDD isomer 2,3,7,8-tetra-CDD was not detected, nor was penta-CDD. There was no difference (P>0.05) in residue concentrations between stations or over time and meteorological parameters were not correlated with residue concentrations. Because contaminant levels and patterns may differ seasonally, we recommend that air samples collected during winter months also be analyzed for these same chemical groups.

Aerosat sampling of PCDD/PCDF emissions from the Gulf oil spill in situ burns

EPA Science Inventory

Emissions from the in situ burning of oil in the Gulf of Mexico after the catastrophic failure of the Deepwater Horizon drilling platform were sampled for polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/PCDFs). A battery-operated instrument package was lo...

EFFECT OF SOOT, TEMPERATURE AND RESIDENCE TIME ON PCDD/F FORMATION

EPA Science Inventory

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during thermal processes in the presence of fly ash that acts as an oxidation catalyst as well as a carbon and chloride source. Recent laboratory studies pointed out the importance of s...

MECHANISTIC STEPS IN THE PRODUCTION OF PCDD AND PCDF DURING WASTE COMBUSTION

EPA Science Inventory

Research has shown that synthesis of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) during municipal waste combustion can proceed through a three step mechanism including 1) production of Cl₂ from a metal-catalyzed reaction of HCl a...

EVALUATION OF THE FULL-SCALE BASE CATALYZED DECOMPOSITION PROCESS (BCDP) UNIT LOCATED IN GUAM

EPA Science Inventory

This report summarizes performance data collected in February 1997 on the removal of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) from soil fed to a first-stage rotary kiln reactor of the Base Catalyzed Dec...

Framework for Application of the Toxicity Equivalence Methodology for Polychlorinated Dioxins, Furans, and Biphenyls in Ecological Risk Assessment (Final)

EPA Science Inventory

Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) are persistent contaminants found widely in the environment. Several of these compounds bioaccumulate in the tissues of fish, birds, and mammals and have been shown to cause mortality and adver...

AN ALTERNATIVE METHOD FOR ESTABLISHING TEFS FOR DIXON-LIKE COMPOUNDS. PART 2. DEVELOPMENT OF AN APPROACH TO QUANTITATIVELY WEIGHT THE UNDERLYING POTENCY DATA

EPA Science Inventory

The current approach for evaluating potential health risks associated with exposure to mixtures of polychlorinated dibenzo-p-dixoins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (PCBs) [hereafter referred to as "dioxin-like compoun...

POLYCHLORINATED DIBENZO-P-DIOXINS AND DIBENZOFURANS: CORRELATION BETWEEN IN VITRO AND IN VIVO STRUCTURE ACTIVITY RELATIONSHIPS (SARS)

EPA Science Inventory

Polychlorinated dibenzofurans (PCDFs) and dibenzo-p-dioxins (PCDDs) elicit a number of common biologic and toxic responses which are triggered by their initial binding to a cytosolic receptor protein. hese effects include the induction of several cytochrome P-448 dependent monoox...

AN ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA) FOR DETERMINING DIOXINS IN SEDIMENT AND SOIL SAMPLES

EPA Science Inventory

The dioxins comprise a family of compounds chemically referred to as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The most toxic of these compounds is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a known human carcinogen. Dioxins are formed ...

ASSESSMENT OF PCDDS (POLYCHLORINATED DIBENZODIOXINS) AND PCDFS (POLYCHLORINATED DIBENZOFURANS) FROM PCB (POLYCHLORINATED BIPHENYL'S) TRANSFORMER AND CAPACITOR FIRES

EPA Science Inventory

The EPA, under the Toxic Substances Control Act, has been mandated to develop appropriate regulations for the control of exposure to polychlorinated biphenyls (PCBs). In light of this responsibility the EPA Office of Toxic Substances recently issued an Advance Notice of Proposed ...

AN ALTERNATIVE METHOD FOR ESTABLISHING TEFS FOR DIOXIN-LIKE COMPOUNDS. PART 1. EVALUATION OF DECISION ANALYSIS METHODS FOR USE IN WEIGHTING RELATIVE POTENCY DATA

EPA Science Inventory

A number of investigators have recently examined the utility of applying probabilistic techniques in the derivation of toxic equivalency factors (TEFs) for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (...

BIOTA-SEDIMENT ACCUMULATION FACTORS FOR POLYCHLORINATED BIPHENYLS, DIBENZO-P-DIOXINS, AND DIBENZOFURANS IN SOUTHERN LAKE MICHIGAN LAKE TROUT (SALVELINUS NAMAYCUSH)

EPA Science Inventory

A set of high-quality, age-specific biota-sediment accumulation factors (BSAFs) for polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs) have been determined from concentrations measured with high-resolution gas chroma tography/high-resolution ma...

THE EFFECT OF METAL CATALYSTS ON THE FORMATION OF POLYCHLORINATED DIBENZO-P-DIOXIN AND POLYCHLORINATED DIBENZOFURAN PRECURSORS

EPA Science Inventory

The catalytic effects of copper and iron compounds were examined for their behavior in promoting formation of chlorine (Cl₂), the major chlorinating agent of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), in an environment simulati...

2,3,7,8-DIBENZO-P-DIOXINS IN MINED CLAY PRODUCTS ...

EPA Pesticide Factsheets

Ball clay was the source of dioxin contamination discovered in selected chickens analyzed as part of a joint U.S. Department of Agriculture/U.S. Environmental Protection Agency national survey of the U.S. poultry supply conducted in 1997. The affected animals, which had been raised in the southern United States, represented approximately 5% of the national poultry production . All of these chickens and other animal food sources (i.e., farm-raised catfish), similarly contaminated, were fed a diet of animal feed containing ball clay as an anti-caking additive. The clay was mined in northwestern Mississippi within a geological formation referred to as the Mississippi Embayment. Individual raw and processed ball clay samples were analyzed for the presence of the 2,3,7,8-PCDDs/PCDFs. The average toxic equivalents (TEQs) for the raw and processed samples were 1513 and 996 ppt dry weight, respectively. Other mined clay-based products used in animal feeds revealed lower TEQs. All of the products exhibited either an absence of detectable concentrations of 2,3,7,8-PCDFs or concentrations 2-3 orders of magnitude lower than the PCDDs. The isomer distribution, specific isomer identification, and congener profile of the PCDDs in the clay were established and compared to known sources of dioxin contamination. Several unique features of this isomer distribution are characteristic of the clays and are distinguishable from those other known sources. These characteristic

DETERMINATION OF THE VAPOR PRESSURES OF SELECT POLYCHLORINATED DIBENZO-P-DIOXINS AND DIBENZOFURANS AT 75–275°C

EPA Science Inventory

Vapor pressures were determined for several polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) at 75–275°C, extending the available literature data to more relevant temperature regions and providing the first experimental data for 2,3,7...

AN ALTERNATIVE METHOD FOR ESTABLISHING TEFS FOR DIOXIN-LIKE COMPOUNDS. PART 3. DEVEOPMENT OF WEIGHTED DISTRIBUTIONS OF REPS FOR PCB 126 AND 2,3,4,7,8-PECDF

EPA Science Inventory

Currently, regulatory agencies utilize the toxic equivalency factor (TEF) approach to evaluate potential health risks associated with exposure to polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (PCBs). Th...

Public-health assessment for American Creosote Works Inc. , Pensacola, Escambia County, Florida, Region 4. CERCLIS No. FLD008161994. Final report

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

Not Available

1992-07-29

The American Creosote Works, Inc., National Priorities List (NPL) site, is near Pensacola Bay in Pensacola, Florida. American Creosote operated a wood preserving business from 1902 until 1981. Soils, buried sludge, ground water, sediments, and air are contaminated with numerous of chemicals including; pentachlorophenol, polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and benzene. Children trespassing on the site are likely to be exposed to pentachlorophenol, PAHs, and PCDDs/PCDFs in the soil via incidental ingestion and may suffer chloracne, liver damage, and an increased risk of cancer. Incidental ingestion of off-site soil by children may also increase theirmore » risk of chloracne and liver damage, but actual health effects depend on the frequency and duration of the exposure. Inhalation of benzene in the on-site air may increase the lifetime risk of cancer for children and other site trespassers. The site is a public health hazard due to the risk of adverse health effects from long term exposure to hazardous chemicals in the air, soil, and ground water.« less

Use of the semipermeable membrane device as an in situ sampler of waterborne bioavailable PCDD and PCDF residues at sub-parts-per-quadrillion concentrations

USGS Publications Warehouse

Lebo, Jon A.; Gale, Robert W.; Petty, Jimmie D.; Tillitt, Donald E.; Huckins, James N.; Meadows, John C.; Orazio, Carl E.; Echols, Kathy R.; Schroeder, Dennis J.; Inmon, Lloyd E.

1995-01-01

Semipermeable membrane devices (SPMDs) were used to passively sample aqueous polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in Bayou Meto, AR. The two sites were upstream and downstream from the confluence with a tributary that delivers PCDDs and PCDFs to the Bayou. Following dialysis, cleanup, and fractionation, four replicate 17-9 SPMD samples from each site were analyzed by GUMS, and four were evaluated by H411E bioassay. Traces of only OCDD and HpCDDs were detected in samples from the upstream site. The four samples from below the tributary contained averages of 1550 ± 80 pg of 2,3,7,8-TCDD, 1640 ± 80 pg of 2,3,7,8-TCDF, and lesser quantities of other congeners. The TCDD equivalents obtained by bioassay of replicate SPMD samples agreed well with results obtained by GC/MS. The quantities of 2,3,7,8- TCDD and 2,3,7,8-TCDF sequestered by SPMDs at the downstream site were used to estimate the aqueous concentrations for both compounds as 2 pg/L.

Polybrominated, polychlorinated and monobromo-polychlorinated dibenzo-p-dioxins/dibenzofurans and dioxin-like polychlorinated biphenyls in marine surface sediments from Hong Kong and Korea.

PubMed

Terauchi, Hidenori; Takahashi, Shin; Lam, Paul K S; Min, Byung-Yoon; Tanabe, Shinsuke

2009-03-01

In this study we investigated occurrences and distribution patterns of dioxin-related compounds (DRCs) such as polybrominated dibenzo-p-dioxins/dibenzofurans (PBDD/Fs), polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), monobromo-polychlorinated dibenzo-p-dioxins/dibenzofurans (MoBPCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in marine surface sediments collected from the coastal waters of Hong Kong and Korea. In most sampling sites, concentrations of PCDDs were the highest, followed by DL-PCBs, PCDFs, PBDFs, PBDDs, MoBPCDDs and MoBPCDFs in this order. Levels of PBDD/Fs were generally 1-2 orders of magnitude lower than chlorinated analogues. Levels of PCDDs are higher than PCDFs in Hong Kong while levels of PBDFs are higher than PBDDs in Korea (p<0.05). Report of PBDD/Fs and MoBPCDD/Fs in sediments from East Asian countries is novel and original. Environmental levels of PBDD/Fs are supposed to start increasing in accordance with rising production, use and disposal of brominated flame retardants (BFRs) and recycling processes of e-waste in Asian developing countries.

Polycyclic Aromatic Hydrocarbons and Polychlorinated Dibenzo-p-Dioxins/Dibenzofurans in Microliter Samples of Human Serum as Exposure Indicators

PubMed Central

Xia, Xiaoyan; Carroll-Haddad, Alesia; Brown, Nicole; Utell, Mark J.; Mallon, Timothy; Hopke, Philip K.

2016-01-01

Objective The objectives were: 1) measure polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in 100 μL of human serum and 2) assess PAH and PCDD/PCDF as markers of burn pit exposures during military deployments. Methods PAHs and PCDDs/PCDFs were analyzed in 100μL serum samples collected pre- and post-deployment from 200 persons deployed to Iraq or Afghanistan (CASE); 200 persons not deployed (CONTROL) with GC/MS. Results Naphthalene was found in ~83% of the samples and was statistically different between post-deployment CASE personnel and pre-deployment. 1,2,3,4,6,7,8-Heptachlorodibenzo-p-dioxin, Octachlorodibenzo-p-dioxin, 1,2,3,7,8,9-Hexachlorodibenzofuran, and 1,2,3,4,6,7,8-Heptachlorodibenzofuran were found in ~38% of samples. Concentrations were significantly different between CASE and CONTROL and between pre- and post-deployment samples. Conclusions PAH and PCDD/PCDF in serum can serve as exposure markers and measurements in small volumes is feasible for quantifying exposure to burn pits. PMID:27501107

PCDDs, PCDFs, and coplanar PCBs in albatross from the North Pacific and Southern Oceans: levels, patterns, and toxicological implications.

PubMed

Tanabe, Shinsuke; Watanabe, Mafumi; Minh, Tu Binh; Kunisue, Tatsuya; Nakanishi, Shigeyuki; Ono, Hitoshi; Tanaka, Hiroyuki

2004-01-15

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (coplanar PCBs) were determined in five albatross species collected from the North Pacific and Southern Oceans to assess the north-south differences in residue levels, accumulation patterns, and toxic potential. Black-footed and Laysan albatrosses from the North Pacific Ocean contained higher levels of PCDD/Fs and coplanar PCBs than albatrosses from the Southern Ocean, indicating that emission sources of these contaminants were predominant in the northern hemisphere. Residue levels in albatrosses from the remote North Pacific Ocean far from the point source of pollution were comparable to or higher than those in terrestrial and coastal birds from contaminated areas in developed nations, suggesting the specific exposure and accumulation of PCDD/Fs and coplanar PCBs in albatross. The long life span and ingestion of plastic resin pellets by albatrosses could be the plausible explanations for the elevated accumulation of persistent and lipophilic contaminants including PCDD/Fs and coplanar PCBs in these birds. Relative proportions of PCDFs and coplanar PCBs in albatross were higher than those observed in birds inhabiting terrestrial and coastal areas, suggesting that these toxic chemicals may have higher transportability by air and water than PCDDs. Congener patterns of PCDD/Fs in albatross showed less variability as compared to those in terrestrial species, indicating that contamination patterns of PCDD/Fs were similar within the open ocean environment. Contributions of PCDD/Fs to total TEQs in albatrosses from the open ocean were generally lower than those in terrestrial birds, suggesting different toxic potency of PCDD/Fs and coplanar PCBs on animals inhabiting open ocean and terrestrial environment. Whereas albatrosses from southern oceans retained lower TEQ concentrations, possible adverse effects of PCDD/Fs and coplanar PCBs to black-footed and Laysan albatrosses of the North Pacific Ocean may be suspected from TEQ levels.

EFFECT OF COFIRING COAL ON FORMATION OF POLYCHLORINATED DIBENZO-P-DIOXINS AND DIBENZOFURANS DURING WASTE COMBUSTION

EPA Science Inventory

The effect of cofiring coal with municipal waste on formation of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) was examined by cofiring minor amounts (<7% by wt) of high (3.4% by wt) or low (0.7% by wt) sulfur (S) coal in a municipal waste co...

Passive Sampling Provides Evidence for Neward Bay as a Source of Polychlorinated Dibenzo-p-Dioxins and Furans to the New York/New Jersey, USA, Atmosphere

EPA Science Inventory

Freely dissolved and gas phase polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were measured in the water column and atmosphere at five locations within Newark Bay (New Jersey, USA) from May 2008 to August 2009 with polyethylene (PE) passive ...

A Survey of Polychlorinated Dibenzo-p-dioxins, Polychlorinated Dibenzofurans and Co-planar Polychlorinated Biphenyls in U.S. Meat and Poultry, 2007-2008

USDA-ARS?s Scientific Manuscript database

A statistically-based survey of dioxins and dioxin-like compounds in domestic meat and poultry was conducted by the U.S. Department of Agriculture (USDA) from September 2007 to September 2008. Seventeen toxic polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and three coplanar pol...

Dioxin, furan, PCB, and PBDE levels in U.S. foods: Survey trends and consumer exposure

USDA-ARS?s Scientific Manuscript database

The U.S. Department of Agriculture, Agricultural Research Service (USDA-ARS) and Food Safety and Inspection Service (USDA-FSIS) have conducted statistical surveys for dioxins (PCDDs, PCDFs, and PCBs) and polybrominated diphenyl ethers every 5 years since the mid-1990s (mid-1990s, 2002-3, 2007-8). I...

THE CONCENTRATION AND DISTRIBUTION OF 2,3,7,8-DIBENZO-P-DIOXINS / - FURANS IN CHICKENS

EPA Science Inventory

The concentrations of 2,3,7,8-Cl substituted dibenzo-p-dioxins/-furans (PCDDs/PCDFs) were determined in the edible tissues of whole chicken fryers and compared with the values found in their abdominal fat. The values are presented both on a whole weight basis and on a lipid-adju...

DIBENZO-P-DIOXINS IN THE ENVIRONMENT FROM CERAMICS AND POTTERY PRODUCED FROM BALL CLAY MINED IN THE U.S.

EPA Science Inventory

Processed ball clay samples used in the production of ceramics and samples of the ceramic products were collected and analyzed for the presence and concentration of the 2,3,7,8-Cl substituted polychlorinated dibenzo-p-dioxins and furans (PCDDs/PCDFs). The processed ball clay had...

Dioxins, dioxin-like compounds, and PBDEs in the U.S. domestic meat supply: trends and levels 2003 to 2013

USDA-ARS?s Scientific Manuscript database

In the mid-1990s, 2002-2003, 2007-2008, and again in 2012-2013 the U.S. Department of Agriculture (USDA) conducted statistical surveys for dioxin and dioxin-like compound (PCDDs, PCDFs, and PCBs) residues in domestic meat and poultry. The surveys were conducted to determine background levels of diox...

Survey of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and non-orthopolychlorinated biphenyls in U.S. meat and poultry from 2012-2013: Toxic equivalency levels, patterns, temporal trends, and implication

USDA-ARS?s Scientific Manuscript database

The U.S. Department of Agriculture (USDA) conducts a statistically-based survey of the domestic meat supply (beef, pork, chicken, and turkey) to determine current levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and non-ortho-polychlorinated biphenyls (no-P...

Effect of solid waste landfill organic pollutants on groundwater in three areas of Sicily (Italy) characterized by different vulnerability.

PubMed

Indelicato, Serena; Orecchio, Santino; Avellone, Giuseppe; Bellomo, Sergio; Ceraulo, Leopoldo; Di Leonardo, Rossella; Di Stefano, Vita; Favara, Rocco; Candela, Esterina Gagliano; La Pica, Leonardo; Morici, Sabina; Pecoraino, Giovannella; Pisciotta, Antonino; Scaletta, Claudio; Vita, Fabio; Vizzini, Salvatrice; Bongiorno, David

2017-07-01

The aim of this study was to obtain information on the presence and levels of hazardous organic pollutants in groundwater located close to solid waste landfills. Eighty-two environmental contaminants, including 16 polycyclic aromatic hydrocarbons (PAHs), 20 volatile organic compounds (VOCs), 29 polychlorinated biphenyls (PCBs), 7 dioxins (polychlorinated dibenzo-p-dioxins, PCDDs) and 10 furans (polychlorinated dibenzofurans, PCDFs) were monitored in areas characterised by different geological environments surrounding three municipal solid waste landfills (Palermo, Siculiana and Ragusa) in Sicily (Italy) in three sampling campaigns. The total concentrations of the 16 PAHs were always below the legal threshold. Overall, the Fl/Fl + Py diagnostic ratio revealed that PAHs had a petrogenic origin. VOC levels, except for two notable exceptions near Palermo landfill, were always below the legal limit. As concerns PCB levels, several samples were found positive with levels exceeding the legal limits. It is worth noting that the % PCB distribution differs from that of commercial compositions. In parallel, some samples of groundwater containing PCDDs and PCDFs exceeding the legal threshold were also found. Among the 17 congeners monitored, the most abundant were the highest molecular weight ones.

Reduction of PCDDs/PCDFs in MSWI fly ash using microwave peroxide oxidation in H2SO4/HNO3 solution.

PubMed

Chang, Yu-Min; Dai, Wen-Chien; Tsai, Kao-Shen; Chen, Shiao-Shing; Chen, Jyh-Herng; Kao, Jimmy C M

2013-05-01

Microwave peroxide oxidation (MPO) is an energy-efficient and low GHG emission technology to destroy the hazardous organic compounds in solid waste. The objective of this paper is to explore the reduction feasibility of PCDDs/Fs in MSWI fly ash using the MPO in H2SO4/HNO3 solution. Nearly all PCDDs/Fs, 99% in the original fly ash, can be reduced in 120min at the temperature of 150°C using the MPO treatment. It was also found that a change occurred in the content distribution profiles of 17 major PCDD/F congeners before and after MPO treatment. This provides the potential to reduce the actual PCDDs/Fs content more than I-TEQ contents of PCDDs/Fs. The percentile distribution profile has a tendency of higher chlorinated PCDDs/Fs moving to the lower ones. It concludes that a significant reduction efficiency of I-TEQ toxicity was achieved and showed sufficient reduction of toxic level to lower than 1.0ngI-TEQ(gdw)(-1). The treatment temperature would be a critical factor facilitating the dissolution because higher temperature leads more inorganic salt (parts of fly ash) dissolution. Some problems caused by the MPO method are also delineated in this paper. Copyright © 2013 Elsevier Ltd. All rights reserved.

National Dioxin Air Monitoring Network (Ndamn) Report of the Results of Atmospheric Measurements of Pcdds, Pcdfs, and Dioxin-Like PCBs in Rural and Remote Areas of the U.S. from June 1998 Through November 2004

EPA Science Inventory

In 1998, the U.S. Environmental Protection Agency (U.S. EPA) established the National Dioxin Air Monitoring Network (NDAMN) to help characterize the ubiquitous presence of dioxins in the environment. This final report represents the 2013 update to NDAMN.

RELATIVE POTENCY BASED ON HEPATIC ENZYME INDUCTION PREDICTS IMMUNOSUPPRESSIVE EFFECT OF A MIXTURE OF POLYCHLORINATED DIBENZO-P-DIOXINS (PCDDS), DIBENZOFURANS (PCDFS) AND BIPHENYLS (PCBS)

EPA Science Inventory

ABSTRACT
). Mixture (MIX)-1 contained TCDD , 2,3,7,8-tetrachlorodibenzofuran (TCDF), 1,2,3,7,8-pentachlorodibenzofuran (1-PeCDF), 2,3,4,7,8-pentachlorodibenzofuran (4-PeCDF), and 1,2,3,4,6,7,8,9-octachlorodibenzofuran (OCDF). MIX-2 was prepared by adding PCBs to MIX-1, the P...

Journal Article: Atmospheric Measurements of CDDs, CDFs, and Coplanar PCBs in Rural and Remote Locations of the U.S. for the Years 1998-2001 from the National Dioxin Air Monitoring Network (Ndamn)

EPA Science Inventory

The U.S. EPA established a National Dioxin Air Monitoring Network (NDAMN) to determine background air concentrations of PCDDs, PCDFs, and cp-PCBs in rural and remote areas of the United States. Background is defined as average ambient air concentrations inferred from long-term a...

Origin of PCDDs in ball clay assessed with compound-specific chlorine isotope analysis and radiocarbon dating.

PubMed

Holmstrand, Henry; Gadomski, Damien; Mandalakis, Manolis; Tysklind, Mats; Irvine, Robert; Andersson, Per; Gustafsson, Orjan

2006-06-15

Polychlorinated dibenzo-p-dioxins (PCDDs) of high concentrations in a ball clay deposit from the Mississippi Embayment were found to be consistent with a natural abiotic and non-pyrogenic origin by investigation with bulk radiocarbon analysis, compound-specific chlorine isotope analysis (CSIA-delta37Cl) of octachlorodibenzo-p-dioxin (OCDD), and black carbon (BC) analysis. The conventional radiocarbon date of total organic carbon from a depth of approximately 10 m in three parallel cores ranged from 14 700 years to >48 000 years, indicating that the strata with elevated levels of PCDDs have remained isolated from recent anthropogenic input in these >40 Ma old clay sediments. The CSIA-delta37Cl of OCDD yielded a delta37Cl of -0.2 per thousandth, which is significantly higher than the postulated range for biotic chlorination by chloroperoxidase enzymes, -11 to -10 per thousandth, and falls within the known range for abiotic organochlorines, -6 to +3 per thousandth. The absence of correlations between concentrations of PCDDs and corresponding pyrogenic black carbon (BC), together with estimations of BC sorptive loadings and the absence of polychlorinated dibenzofurans (PCDFs), suggest that vegetation fires did not form these ball-clay PCDDs. Results from this study indicate that the high levels of the toxic and carcinogenic PCDDs found in kaolinite-bearing clays may result from natural abiotic formation via in situ surface-promoted reactions on the clay mineral, including a so-far unknown organic precursor, rather than being the result of anthropogenic contamination.

Polychlorinated dibenzo-p-dioxins and dibenzofurans in the atmosphere around the Great Lakes.

PubMed

Venier, Marta; Ferrario, Joseph; Hites, Ronald A

2009-02-15

The atmospheric concentrations of PCDDs and PCDFs were measured in four sites near the shores of the North American Great Lakes. The sites included an urban site (Chicago, Illinois) and three rural/remote sites (Eagle Harbor, Michigan; Sleeping Bear Dunes, Michigan; and Sturgeon Point, New York). Sampling occurred every 24 days between November 2004 and December 2007. The concentration of PCDD/Fs averaged 2.3 +/- 0.2 fg WHO TEQ/m3 at Eagle Harbor, 35 +/- 3 fg WHO TEO/ m3 at Chicago, 7.4 +/- 1.4 fg WHO TEO/m3 at Sleeping Bear Dunes, and 13 +/- 2 fg WHO TED/m3 at Sturgeon Point. The total concentration of the 17 toxic PCDD/F congeners showed a significant seasonal trend at all sites, except Chicago. The date of maximum concentration averaged Dec 6 +/- 35 days, which is consistent with residential heating being an important source of PCDD/Fs to the atmosphere. A significant positive relationship between the logarithm of the total concentration of the 17 toxic PCDD/F congeners and the logarithm of the number of people within a 25 km radius around the sampling site was found. We suggest that urban and industrial areas, which are heavily populated, act as sources of PCDDs and PCDFs to the atmosphere.

Persistent organic pollutants in chinook salmon (Oncorhynchus tshawytscha): implications for resident killer whales of British Columbia and adjacent waters.

PubMed

Cullon, Donna L; Yunker, Mark B; Alleyne, Carl; Dangerfield, Neil J; O'Neill, Sandra; Whiticar, Michael J; Ross, Peter S

2009-01-01

We measured persistent organic pollutant (POP) concentrations in chinook salmon (Oncorhynchus tshawytscha) in order to characterize dietary exposure in the highly contaminated, salmon-eating northeastern Pacific resident killer whales. We estimate that 97 to 99% of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dichlorodiphenyltrichloroethane (DDT), and hexachlorocyclohexane (HCH) in returning adult chinook were acquired during their time at sea. Highest POP concentrations (including PCBs, PCDDs, PCDFs, and DDT) and lowest lipids were observed in the more southerly chinook sampled. While feeding by salmon as they enter some more POP-contaminated near-shore environments inevitably contribute to their contamination, relationships observed between POP patterns and both lipid content and delta13C also suggest a migration-related metabolism and loss of the less-chlorinated PCB congeners. This has implications for killer whales, with the more PCB-contaminated salmon stocks in the south partly explaining the 4.0 to 6.6 times higher estimated daily intake for sigmaPCBs in southern resident killer whales compared to northern residents. We hypothesize that the lower lipid content of southerly chinook stocks may cause southern resident killer whales to increase their salmon consumption by as much as 50%, which would further increase their exposure to POPs.

Exposure of northern leopard frogs in the Green Bay ecosystem to polychlorinated biphenyls, polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans is measured by direct chemistry but not hepatic ethoxyresorufin-O-deethylase activity

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

Huang, Y.W.; Karasov, W.H.; Patnode, K.A.

1999-10-01

The authors measured concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) in northern leopard frogs collected from the Green Bay ecosystem and explored the catalytic activity of hepatic cytochrome P450-associated monooxygenase (P450 enzyme) as a biomarker for exposure to aryl hydrocarbon receptor (AhR) agonists. The two hypotheses tested were PCH concentrations in northern leopard frogs would be positively correlated with sediment polychlorinated hydrocarbon (PCH) levels in wetland habitats along a contamination gradient and hepatic ethoxyresorufin-O-deethylase (EROD) activity of northern leopard frogs, which is presumably mediated by aryl hydrocarbon receptor (AhR), would be positively correlated with PCHmore » concentrations in frog carcasses from different collection sites. In 1994 and 1995, frogs from seven sites along the lower Fox River and Green Bay, USA, were assayed for hepatic EROD activities and whole carcass concentrations of PCBs, PCDDs, and PCDFs. Tissue total PCB concentrations ranging from 3 to 154 ng/g were significantly correlated with sediment PCB levels. Only one PCDD and two PCDFs at concentrations of 6 to 8 pg/g were found in the frogs collected with frog body weight and was similar among sites except for Peter's Marsh. No significant correlation was found between EROD activity and carcass PCB concentration. This result was consistent with the fact that the frogs collected from the Green Bay ecosystem had relatively low PCB concentrations compared with what was required for induction in the laboratory.« less

Relative effect potency estimates of dioxin-like activity for dioxins, furans, and dioxin-like PCBs in adults based on cytochrome P450 1A1 and 1B1 gene expression in blood.

PubMed

Wimmerová, Soňa; van den Berg, Martin; Chovancová, Jana; Patayová, Henrieta; Jusko, Todd A; van Duursen, Majorie B M; Palkovičová Murínová, Ľubica; Canton, Rocio F; van Ede, Karin I; Trnovec, Tomáš

2016-11-01

In the risk assessment of PCDDs, PCDFs, and dioxin-like (DL) PCBs, regulatory authorities support the use of the toxic equivalency factor (TEF)-scheme derived from a heterogeneous data set of the relative effect potency (REPs) estimates. We sought to determine REPs for dioxin-like compounds (DLCs) using expression of cytochrome P450 (CYP) 1A1 and 1B1 mRNA in human peripheral blood mononuclear cells representing two different pathways. We used a sex and age adjusted regression-based approach comparing the strength of association between each DLC and the cytochrome P450 (CYP) 1A1 and 1B1 mRNA expression in 320 adults residing in an organochlorine-polluted area of eastern Slovakia. We calculated REPs based on CYP1A1 expression for 4 PCDDs, 8 PCDFs, and 1 PCB congener, and based on CYP1B1 expression for 5 PCDFs and 11 PCB congeners. REPs from CYP1A1 correlated with REPs previously derived from thyroid volume (ρ=0.85; p<0.001) and serum FT4 (ρ=0.77; p=0.009). The 13 log REPs from CYP1A1 correlated with log WHO-TEFs (r=0.63; p=0.015) and 11 log PCB REPs with PCB consensus toxicity factors (CTFs) for compounds with WHO-TEFs (r=0.80; p=0.003). The complete set of derived 56 log REPs correlated with the log CTFs (r=0.77; p=0.001) and log WHO-TEFs (r=0.81; p<0.001). REPs calculated from thyroid and cytochrome P450 endpoints realistically reflect human exposure scenarios because they are based on human chronic and low-dose exposures. While the CYP 1A1 seems more suitable for toxicity evaluation of PCDD/Fs, the CYP 1B1 is more apt for PCDFs and PCBs and reflects different pathways. Copyright © 2016 Elsevier Ltd. All rights reserved.

Spatial distribution of polychlorinated dibenzo-p-dioxins and dibenzo-furans (PCDDs/Fs) in dust, soil, sediment and health risk assessment from an intensive electronic waste recycling site in Southern China.

PubMed

Hu, Jianfang; Xiao, Xiao; Peng, Ping'an; Huang, Weilin; Chen, Deyi; Cai, Ying

2013-10-01

Workshop dust, soil and sediment samples were collected to investigate the level and spatial distribution of PCDDs/Fs at an intensive electronic waste (e-waste) recycling site in Southern China, and also to characterize the dioxin emission in different e-waste recycling procedures. The concentrations of total PCDDs/Fs ranged from 1866 to 234292 ng kg(-1) for the dust samples, from 3187 to 63998 ng kg(-1) dry wt for the top soils, and 33718 ng kg(-1) for the surface sediment. All the samples were characterized by abnormally high concentrations of OCDD and an extremely low portion of PCDFs. Different e-waste recycling procedures may generate different congener profiles. Open burning and dismantling were the two procedures emitting relatively higher concentrations of PCDDs/Fs in this case, indicating that low-tech recycling operations were one of the major contributors of PCDDs/Fs to the environment. The variation and distinction of the concentrations and homologue/congener profiles among different environmental matrices reveal the characteristics of contaminant environmental behavior and fate during the transportation from "source" to "sink". Daily intake of PCDDs/Fs through soil ingestion and dermal absorption was negligible, but the rough estimated total PCDD/F intake dose far exceeded the tolerance daily intake value of 4 pg-TEQ per kg per day recommended by WHO, indicating that residents in Longtang were at a high risk of exposure to dioxins, especially children.

Dioxin, furan and PCB serum levels in a South African Tswana population: comparing the polluting effects of using different cooking and heating fuels.

PubMed

Pieters, Rialet; Focant, Jean-François

2014-05-01

In South Africa, 26-50% of households use solid fuel for cooking food and heating houses. When used as fuel, wood and chlorinated waste are known sources of polychlorinated dibenzo-para-dioxins, polychlorinated dibenzofurans (PCDD/Fs), and polychlorinated biphenyls (PCBs). Here, we compare PCDD/F, dioxin-like PCB (DL-PCB), and non-DL-PCB (NDL-PCB) levels in serum of 693 Tswana individuals in the North West province, who either burn solid biofuels or have access to electricity, gas, and paraffin. This is the first South African study on dioxin levels in humans with more than 100 participants. Serum was pooled according to fuel use, as well as to confounding factors such as gender and age. Solid-phase extraction was used to remove the target analytes from serum, after which the extracts were further refined automatically using a combination of multilayer sorbents. Compound concentrations were determined by high-resolution mass spectrometry after high-resolution gas chromatography. Mean serum lipid content was determined enzymatically to be 5.91 ± 0.42 g/L. The PCDD/F and DL-PCB levels were similar to global concentrations reported for non-exposed adults. The mean of the total Toxic Equivalencies (ΣTEQ) was 6.9 ± 3.3 pg/g lipid and the mean NDL-PCB was 70.1 ± 42.8 ng/g lipid. The mean concentrations of the PCDDs, PCDFs and the corresponding World Health Organization-TEQ (WHO-TEQ) of the population using electricity, gas, and paraffin were greater than of those reliant on solid biomass (p = 0), whereas the DL-PCBs, their corresponding WHO-TEQ, and NDL-PCBs were greater for the population who use biofuels but not significantly so. The females had higher serum levels of the PCDDs (p = 0) and PCDFs (not significant) whereas the PCBs were higher for the males (p = 0). Breastfeeding women presented lower levels of all compound classes than their non-breastfeeding counterparts (p=0) and older subjects manifested greater pollutant loads than the younger generation (p = 0). For our study population, being regularly exposed to the combustion of solid biofuels caused higher serum levels of DL-PCBs and NDL-PCBs but not of PCDDs and PCDFs. Copyright © 2014 Elsevier Ltd. All rights reserved.

Semivolatile and volatile organic compound emissions from wood-fired hydronic heaters.

PubMed

Aurell, Johanna; Gullett, Brian K; Tabor, Dennis; Touati, Abderrahmane; Oudejans, Lukas

2012-07-17

Emissions including polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), polyaromatic hydrocarbons (PAHs), and volatile organic compounds (VOCs), were sampled from different wood-fired hydronic heater (HH) technologies. Four commercially available HH technologies were studied: a single-stage conventional combustor with natural updraft, a three-stage downdraft combustion system, a bottom-fed pellet burner, and a two-stage heater with both a combustion and gasification chamber. The fuel consisted of three wood types (red oak, white pine, and white ash), one hardwood pellet brand, and one fuel mixture containing 95% red oak and 5% residential refuse by weight. The various HHs and fuel combinations were tested in a realistic homeowner fuel-charging scenario. Differences in emission levels were found between HH technologies and fuel types. PCDD/PCDF emissions ranged from 0.004 to 0.098 ng toxic equivalency/MJ(input) and PAHs from 0.49 to 54 mg/MJ(input). The former was increased by the presence of 5% by weight refuse. The white pine fuel had the highest PAH emission factor, while the bottom fed pellet burner had the lowest. The major VOCs emitted were benzene, acetylene, and propylene. The highest emissions of PAHs, VOCs, and PCDDs/PCDFs were observed with the conventional unit, likely due to the rapid changes in combustion conditions effected by the damper opening and closing.

Levels of PCDDs and PCDFs in human milk from populations in Madrid and Paris

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

Gonzalez, M.J.; Hernandez, L.M.; Jimenez, B.

Human breast milk represents a good substrate to examine the polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) background contamination of a population and also supplies important information about the exposure risk for nursing infants. Although adipose tissue and blood samples are commonly studied in the literature milk Dioxin levels are more specifically of concern because of the facility of sampling and also the potential health damage which may be caused to the breastfed babies by those highly toxic synthetic chemicals. The occurrence of dioxins in mother milk among the general population in all countries studied until now, has confirmed a widespread pollutionmore » and intake of those compounds. Dietary and other sources such as contaminated chemicals, industrial activity, waste combustion and leaded car gasoline may be responsible for such a contamination, and also for the differences among levels found in different countries. Human contamination by PCDDs and PCDFs from the environment is clearly a multisource problem. Human milk as well as other human fluids studies up to know have only found the presence of 2,3,7,8 substituted PCDD or PCDF congeners present. The reason for this congener specific retention is usually explained by the metabolic conversion on the 2,3,7, and 8 lateral positions in combination with high binding affinities for the cytosolic receptor proteins.« less

Organohalogen concentrations and feeding status in Atlantic salmon (Salmo salar L.) of the Baltic Sea during the spawning run.

PubMed

Vuorinen, Pekka J; Kiviranta, Hannu; Koistinen, Jaana; Pöyhönen, Outi; Ikonen, Erkki; Keinänen, Marja

2014-01-15

Changes in the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in Baltic salmon muscle were studied during the spawning migration from the southern Baltic Sea to rivers flowing into the northern Gulf of Bothnia and during the spawning period. The aim was to obtain information to facilitate the arrangement of salmon fisheries such that the human dioxin intake is taken into account. The EC maximum allowable total toxic equivalent concentration (WHO-TEQPCDD/F+PCB) was exceeded in the muscle of the majority of the migrating salmon, except in the Baltic Proper. The fresh-weight-based concentrations of all toxicant groups in salmon tended to be the lowest in the Baltic Proper and the Northern Quark, and all toxicant concentrations, except PCDDs and PCDFs, were significantly higher in the spawning salmon than in the salmon caught during the spawning run. The fat content of the salmon muscle decreased by 60% during the spawning run, and the lipid-based total toxicant concentrations were consequently 4.2-6.2 times higher during the spawning period than during the spawning migration. However, the toxicants were concentrated just before spawning, and thus there is no essential difference related to whether the salmon are caught in the sea or the recreational river fishery. © 2013.

Sludge incineration tests on circulating fluidised bed furnace.

PubMed

Lotito, V; Mininni, G; Di Pinto, A C; Spinosa, L

2001-01-01

Results of sludge incineration tests on a demonstrative fluidised bed furnace are reported and discussed. They show that particulate, heavy metals and acidic compounds in the emissions can be easily controlled both when sludge is spiked with chlorinated hydrocarbons up to a chlorine concentration in the feed of 5%, and when the afterburner is switched off. As for organic micropollutants, polynuclear aromatic hydrocarbons (PAH) were much lower than the Italian limits of 10 microg/m3 (no limits are at present considered in the European Directives). Dioxins (PCDDs) and furans (PCDFs) in some tests exceeded the limit of 0.1 ng/m3 (TE) but the concentrations in the fly ashes were much lower, thus evidencing a possible presence of contaminants in gas phase. PAHs and PCDD/PCDFs were not depending on the afterburning operation, the presence of organic chlorine in the feed sludge and the copper addition to sewage sludge.

Polychlorinated dibenzo-p-dioxins and the human immune system: 4 studies on two Spanish families with increased body burdens of highly chlorinated PCDDs.

PubMed

Smith, Andrew G; Hansson, Marriane; Rodriguez-Pichardo, Antonio; Ferrer-Dufol, Ana; Neubert, Reinhard T; Webb, Jessie R; Rappe, Christopher; Neubert, Diether

2008-04-01

The consequences of exposure of people to highly chlorinated polychlorodibenzo-p-dioxins (PCDDs) are much less known than those of TCDD. We report on levels of PCDDs (and PCDFs) in 13 members of two families poisoned by contaminated cooking oil. Originally, all persons displayed chloracne as an early symptom. Persisting hexa- and higher chlorinated PCDDs could be analysed many years after exposure. Highest values found in blood lipids were: OCDD 660,000 pg/g; HpCDD 58,000 pg/g; HxCDDs: 3500 pg/g. None of the participants exhibited increased TCDD levels at the time of study. During a period of 6 years, HpCDD and OCDD disappeared from the blood lipids much faster in persons exposed as children or young adults, than from lipids of their parents. Surface receptors on blood lymphocytes of the members of the two families and the proliferative capacity of these blood cells in the presence of typical stimulants were analysed. Even in family members with the highest body burdens of hexa- to octachlorinated PCDDs we could not detect pronounced changes from a reference population with respect to the immunological markers. Minor deviations of levels of some receptors in a few, but not all, highly exposed persons suggested a similar trend to those reported in previous studies of persons with body burdens of > or =3000 pg TCDD/g blood lipids. An increase in the number of total blood lymphocytes in some subjects exposed as children may have similarity with highly TCDD-exposed children in Seveso.

Alkali Potassium Induced HCl/CO2 Selectivity Enhancement and Chlorination Reaction Inhibition for Catalytic Oxidation of Chloroaromatics.

PubMed

Sun, Pengfei; Wang, Wanglong; Weng, Xiaole; Dai, Xiaoxia; Wu, Zhongbiao

2018-06-05

Industrial combustion of chloroaromatics is likely to generate unintentional biphenyls (PCBs), polychlorinated dibenzo- p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs). This process involves a surface-mediated reaction and can be accelerated in the presence of a catalyst. In the past decade, the effect of surface nature of applied catalysts on the conversion of chloroaromatics to PCBs/PCDD/PCDF has been well explored. However, studies on how the flue gas interferent components affect such a conversion process remain insufficient. In this article, a critical flue gas interferent component, alkali potassium, was investigated to reveal its effect on the chloroaromatics oxidation at a typical solid acid-base catalyst, Mn x Ce 1- x O 2 /HZSM-5. The loading of alkali potassium was found to improve the Lewis acidity of the catalyst (by increasing the amounts of surface Mn 4+ after calcination), which thus promoted the CO 2 selectivity for catalytic chlorobenzene (CB) oxidation. The KOH with a high hydrophilicity has favored the adsorption/activation of H 2 O molecules that provided sufficient hydroxyl groups and possibly induced a hydrolysis process to promote the formation of HCl. The K ion also served as a potential sink for chorine ions immobilization (via forming KCl). Both of these inhibited the formation of phenyl polychloride byproducts, thereby blocking the conversion of CB to chlorophenol and then PCDDs/PCDFs, and potentially ensuring a durable operation and less secondary pollution for the catalytic chloroaromatics combustion in industry.

Journal Article: Atmospheric Measurements of CDDs, CDFs ...

EPA Pesticide Factsheets

The U.S. EPA established a National Dioxin Air Monitoring Network (NDAMN) to determine background air concentrations of PCDDs, PCDFs, and cp-PCBs in rural and remote areas of the United States. Background is defined as average ambient air concentrations inferred from long-term and multi-year atmospheric measurements at the same locations using identical monitoring and analytical procedures. The rural sites were chosen in order to obtain air concentrations in areas where crops and livestock are grown, and that encompassed a range of geographic locations in terms of latitudinal and longitudinal positions. Remote sites were selected on the basis that they were relatively free of human habitation and >100 km away from human dioxin sources. The locations of sampling sites covered a wide range of climate conditions from tropical sub-humid to sub-Artic climates. The idea behind the sampling configuration was to provide reasonable geographic coverage of the United States limited only by budgetary constraints. Funding was sufficient for the establishment and maintenance of 34 NDAMN stations over a period of 6 years. Results were reported as the toxic equivalent (TEQ) of the mix of PCDDs/PCDFs (TEQ-DF) and the mix of coplanar PCBs (TEQ-PCB). At the studied rural sites the mean annual TEQ-DF for each of the NDAMN sampling years was 10.43, 11.39, 10.40, and 10.47 femtograms per cubic meter (fg/cu. m) for 1999, 2000, 2001, and 2002, respectively.There was no statistical

Relationships between environmental organochlorine contaminant residues, plasma corticosterone concentrations, and intermediary metabolic enzyme activities in Great Lakes herring gull embryos.

PubMed Central

Lorenzen, A; Moon, T W; Kennedy, S W; Glen, G A

1999-01-01

Experiments were conducted to survey and detect differences in plasma corticosterone concentrations and intermediary metabolic enzyme activities in herring gull (Larus argentatus) embryos environmentally exposed to organochlorine contaminants in ovo. Unincubated fertile herring gull eggs were collected from an Atlantic coast control site and various Great Lakes sites in 1997 and artificially incubated in the laboratory. Liver and/or kidney tissues from approximately half of the late-stage embryos were analyzed for the activities of various intermediary metabolic enzymes known to be regulated, at least in part, by corticosteroids. Basal plasma corticosterone concentrations were determined for the remaining embryos. Yolk sacs were collected from each embryo and a subset was analyzed for organochlorine contaminants. Regression analysis of individual yolk sac organochlorine residue concentrations, or 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs), with individual basal plasma corticosterone concentrations indicated statistically significant inverse relationships for polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs), total polychlorinated biphenyls (PCBs), non-ortho PCBs, and TEQs. Similarly, inverse relationships were observed for the activities of two intermediary metabolic enzymes (phosphoenolpyruvate carboxykinase and malic enzyme) when regressed against PCDDs/PCDFs. Overall, these data suggest that current levels of organochlorine contamination may be affecting the hypothalamo-pituitary-adrenal axis and associated intermediary metabolic pathways in environmentally exposed herring gull embryos in the Great Lakes. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:10064546

Persistent organic pollutant concentrations in first birth mothers across Mexico.

PubMed

Rodríguez-Dozal, Sandra; Riojas Rodríguez, Horacio; Hernández-Ávila, Mauricio; Van Oostdam, Jay; Weber, Jean Philippe; Needham, Larry L; Trip, Luke

2012-01-01

This project was initiated by the North America Commission for Environmental Cooperation (CEC). Its main purpose was to obtain an initial profile on pregnant woman's exposure to persistent organic pollutants (POPs) in North America (Canada, the United States and Mexico). Persistent organic pollutants are transferred to the fetus via the placenta during the pregnancy or to the infant via maternal milk; therefore, the pregnant woman's body burden is important because of the higher exposures and potential health effects in the fetus and infant. This paper presents the results from 240 pregnant women in 10 Mexican cities, and includes the concentrations of various POPs such as polychlorinated biphenyls (PCBs), organochlorine pesticides and polychlorinated dibenzo dioxins and furans (PCDDs and PCDFs) in maternal plasma. We found concentrations of p,p'-DDE in maternal samples from Coatzacoalcos to be ∼60% higher than those found in Ciudad Obregon, which had the second highest concentration. Pregnant women from Merida had higher mean concentrations of PCBs than all women in other regions. Results for PCDDs and PCDFs plus dioxin-like PCBs data were only available on the basis of composite samples, and their concentrations are similar in most cities except for Coatzacoalcos, which had more than double the concentration found in other cities. Although this study provides useful information on the variability of POPs in specific populations and possible regional/local differences, these results cannot be generalized to the entire Mexican population because of differences in age, gender, sources of exposure and nonrandom nature of the sample.

Baseline soil levels of PCDD/Fs established prior to the construction of municipal solid waste incinerators in China.

PubMed

Liu, Hong-mei; Lu, Sheng-yong; Buekens, Alfons G; Chen, Tong; Li, Xiao-dong; Yan, Jian-hua; Ma, Xiao-jun; Cen, Ke-fa

2012-01-01

In order to determine the baseline contamination by polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in different areas in China, prior to the construction of municipal solid waste incinerators (MSWIs), a total of 32 representative soil samples was collected near 16 incinerators and analyzed for their PCDD/F concentrations. The PCDD/F baseline concentrations in the soil samples ranged from 0.32 to 11.4 ng I-TEQ kg(-1) (dry matter), with average and median value of 2.73 and 2.24 ng I-TEQ kg(-1) (dry matter), respectively, and a span between maximum and minimum recorded value of 36. The PCDD homologues predominated in 26 out of 32 soil samples, with the ratio (PCDDs)/(PCDFs) ranging from 1.1 to 164; however in the other 6 samples, PCDF homologues were larger, with the same ratio varying from 0.04 to 0.8. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to examine PCDD/F amount and profile in these soil samples, and their possible associations with known emission sources: in this process 6 really distinct isomer fingerprints were identified. Background PCDD/F levels and profiles were comparable to those found in soils from China and other countries and indicate a rather low baseline PCDD/F contamination of soils. The present data provide the tools for future assessment of a possible impact of these MSWIs. Copyright © 2011 Elsevier Ltd. All rights reserved.

Serum Concentrations of Selected Persistent Organic Pollutants in a Sample of Pregnant Females and Changes in Their Concentrations during Gestation

PubMed Central

Wang, Richard Y.; Jain, Ram B.; Wolkin, Amy F.; Rubin, Carol H.; Needham, Larry L.

2009-01-01

Objectives In this study we evaluated the concentrations of selected persistent organic pollutants in a sample of first-time pregnant females residing in the United States and assessed differences in these concentrations in all pregnant females during gestation. Methods We reviewed demographic and laboratory data for pregnant females participating in the National Health and Nutrition Examination Survey, including concentrations of 25 polychlorinated biphenyls (PCBs), 6 polychlorinated dibenzo-p-dioxins (PCDDs), 9 polychlorinated dibenzofurans (PCDFs), and 9 organochlorine pesticides. We report serum concentrations for first-time pregnant females (2001–2002; n = 49) and evaluate these concentrations in all pregnant females by trimester (1999–2002; n = 203) using a cross-sectional analysis. Results The chemicals with ≥ 60% detection included PCBs (congeners 126, 138/158, 153, 180), PCDDs/PCDFs [1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (1234678HpCDD), 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin (123678HxCDD), 1,2,3,4,6,7,8-heptachlorodibenzofuran (1234678HpCDF), 1,1′-(2,2-dichloroethenylidene)-bis(4-chlorobenzene) (p,p′-DDE)], and trans-nonachlor. The geometric mean concentration (95% confidence intervals) for 1234678HpCDD was 15.9 pg/g lipid (5.0–50.6 pg/g); for 123678HxCDD, 9.7 pg/g (5.5–17.1 pg/g); and for 1234678HpCDF, 5.4 pg/g (3.3–8.7 pg/g). The differences in concentrations of these chemicals by trimester were better accounted for with the use of lipid-adjusted units than with whole-weight units; however, the increase in the third-trimester concentration was greater for PCDDs/PCDFs (123678HxCDD, 1234678HpCDF) than for the highest concentration of indicator PCBs (138/158, 153, 180), even after adjusting for potential confounders. Conclusion The concentrations of these persistent organic pollutants in a sample of first-time pregnant females living in the United States suggest a decline in exposures to these chemicals since their ban or restricted use and emission. The redistribution of body burden for these and other persistent organic pollutants during pregnancy needs to be more carefully defined to improve the assessment of fetal exposure to them based on maternal serum concentrations. Additional studies are needed to further the understanding of the potential health consequences to the fetus from persistent organic pollutants. PMID:19672404

Plasma levels of dioxins, furans, non-ortho-PCBs, and TEQs in the Seveso population 17 years after the accident.

PubMed

Consonni, D; Sindaco, Raffaella; Agnello, L; Caporaso, N E; Landi, Maria Teresa; Pesatori, Angela Cecilia; Bertazzi, P A

2012-01-01

The Seveso accident (Italy) in 1976 caused the contamination of a large population by 2,3,7,8-tetrachlorodibenzo-para-dioxin (2,3, 7,8-TCDD). The contaminated territory was divided into three zones: A (very high contamination), B (high contamination), and R (low contamination). We report here the plasma concentrations of seven polychlorinated dibenzo-para-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), four non-ortho-polychlorinated biphenyls PCBs (nPCBs), and Toxic Equivalencies (TEQs) in a sample of residents in the most polluted zones A and B and in a reference non-contaminated zone. From December 1992 to March 1994, 62 individuals were randomly selected from the population living in zone A (No. =7) and B (No. =55). A sample of 59 subjects living in a surrounding non-contaminated area (non-ABR), frequency-matched by gender, age, and smoking history, was used as reference. All subjects were administered a questionnaire surveying demographic, lifestyle, medical history, and accident-related factors. We assayed plasma PCDD, PCDF, and nPCB concentrations by high-resolution gas chromatography/high resolution mass spectrometric (HRGC/HRMS) analysis, with results reported as pg/g of lipid, or parts per trillion (ppt). We calculated TEQs using the WHO 2005 Toxic Equivalency Factors (TEFs). We found elevated median levels of 2,3, 7,8-TCDD in plasma samples of subjects living in zone A (73.3 ppt) and zone B (12.4 ppt), compared with residents in the reference zone (5.5 ppt). In analyses adjusted for gender, age, smoking, and body mass index (BMI), none of the other congeners showed levels higher than reference in the contaminated zones. Compared with men, women showed higher levels (113%) of 2,3, 7,8-TCDD and a slight elevation (17%) of TEQ for the other congeners. Age was strongly positively associated with most congener levels; TEQs for PCDDs, PCDFs, and nPCBs showed respectively 12%, 24%, and 41% increases for every 10 years of age. Current smokers had lower (from -37% to -67%) TEQ levels than subjects who had never smoked. BMI was negatively associated with levels of a few congeners, but with no impact on TEQ values. The Seveso accident caused a severe exposure of the population to 2,3,7,8-TCDD only. None of the other congeners analyzed showed variation across zones. Age showed a strong positive association with TEQs for all classes of compounds (PCDDs, PCDFs, and nPCBs).

Biomagnification factors (fish to osprey eggs from Willamette River, Oregon, U.S.A.) for PCDDS, PCDFS, PCBS, and OC pesticides

USGS Publications Warehouse

Henny, Charles J.; Kaiser, James L.; Grove, Robert A.; Bentley, V.R.; Elliot, J.E.

2003-01-01

A migratory population of 78 pairs of Osprey (Pandion haliaetus) nesting along the Willamette River in westernOregon was studied in 1993. The study was designed to determinecontaminant concentrations in eggs, contaminant concentrationsin fish species predominant in the Ospreys diet, andBiomagnification Factors (BMFs) of contaminants from fish specieseaten to Osprey eggs. Ten Osprey eggs and 25 composite samplesof fish (3 species) were used to evaluate organochlorine (OC)pesticides, polychlorinated biphenyls (PCBs), polychlorinateddibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans(PCDFs). Mercury was also analyzed in fish. Geometric meanresidues in Osprey eggs were judged low, e.g., DDE 2.3 g g-1 wet weight (ww), PCBs 0.69 g g-1, 2,3,7,8-TCDD 2.3 ng kg-1, and generally well below known threshold values for adverse effects on productivity, and the population was increasing. Osprey egg residue data presentedby River Mile (RM) are discussed, e.g., higher PCDDs were generally found immediately downstream of paper mills and eggsfrom the Willamette River had significantly elevated PCBs and PCDDs compared to reference eggs collected nearby in the CascadeMountains. Prey remains at nest sites indicated that the Largescale Sucker (Catostomus macrocheilus) and NorthernPikeminnow (Ptychocheilus oregonensis) accounted for an estimated 90.1% of the biomass in the Osprey diet, and composite samples of these two species were collected from different sampling sites throughout the study area for contaminant analyses. With the large percentage of the fishbiomass in the Osprey diet sampled for contaminants (and fisheaten by Ospreys similar in size to those chemically analyzed),and fish contaminant concentrations weighted by biomass intake, a mean BMF was estimated from fish to Osprey eggs for the largeseries of contaminants. BMFs ranged from no biomagnification(0.42) for 2,3,7,8-TCDF to 174 for OCDD. Our findings for themigratory Osprey were compared to BMFs for the resident HerringGull (Larus argentatus), and differences are discussed. Webelieve a BMF approach provides some basic understanding ofrelationships between contaminant burdens in prey species offish-eating birds and contaminants incorporated into their eggs,and may prove useful in understanding sources of contaminants inmigratory species although additional studies are needed.

Biomagnification factors (fish to Osprey eggs from Willamette River, Oregon, U.S.A.) for PCDDs, PCDFs, PCBs and OC pesticides.

PubMed

Henny, Charles J; Kaiser, James L; Grove, Robert A; Bentley, V Raymond; Elliott, John E

2003-06-01

A migratory population of 78 pairs of Osprey (Pandion haliaetus) nesting along the Willamette River in western Oregon was studied in 1993. The study was designed to determine contaminant concentrations in eggs, contaminant concentrations in fish species predominant in the Ospreys diet, and Biomagnification Factors (BMFs) of contaminants from fish species eaten to Osprey eggs. Ten Osprey eggs and 25 composite samples of fish (3 species) were used to evaluate organochlorine (OC) pesticides, polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs). Mercury was also analyzed in fish. Geometric mean residues in Osprey eggs were judged low, e.g., DDE 2.3 microg g(-1) wet weight (ww), sigma PCBs 0.69 microg g(-1), 2,3,7,8-TCDD 2.3 ng kg(-1), and generally well below known threshold values for adverse effects on productivity, and the population was increasing. Osprey egg residue data presented by River Mile (RM) are discussed, e.g., higher PCDDs were generally found immediately downstream of paper mills and eggs from the Willamette River had significantly elevated PCBs and PCDDs compared to reference eggs collected nearby in the Cascade Mountains. Prey remains at nest sites indicated that the Largescale Sucker (Catostomus macrocheilus) and Northern Pikeminnow (Ptychocheilus oregonensis) accounted for an estimated 90.1% of the biomass in the Osprey diet, and composite samples of these two species were collected from different sampling sites throughout the study area for contaminant analyses. With the large percentage of the fish biomass in the Osprey diet sampled for contaminants (and fish eaten by Ospreys similar in size to those chemically analyzed), and fish contaminant concentrations weighted by biomass intake, a mean BMF was estimated from fish to Osprey eggs for the large series of contaminants. BMFs ranged from no biomagnification (0.42) for 2,3,7,8-TCDF to 174 for OCDD. Our findings for the migratory Osprey were compared to BMFs for the resident Herring Gull (Larus argentatus), and differences are discussed. We believe a BMF approach provides some basic understanding of relationships between contaminant burdens in prey species of fish-eating birds and contaminants incorporated into their eggs, and may prove useful in understanding sources of contaminants in migratory species although additional studies are needed.

Gender-related decrease in raven`s progressive matrices scores in children prenatally exposed to polychlorinated biphenyls and related contaminants

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

Guo, Y.L.; Lai, T.J.; Chen, S.J.

1995-07-01

Polychlorinated biphenyls (PCBs) and industrial mixtures that have been widely used throughout the world. PCBs have long environmental half lives and bioconcentrate, therefore contaminating soil, water, wild life, and human tissues. Typical human exposures come from environmental contamination of food supply, especially fresh water fish and meat, and occupational exposures. In certain uses, PCBs can partially oxidize and themselves become contaminated by extremely toxic compounds such as polychlorinated dibenzofurans (PCDFs). Two episodes of intoxication with heat-degraded PCBs have occurred, in Japan and Taiwan respectively. In 1979, over 2000 persons in Taiwan were intoxicated by heat-degraded PCBs that had contaminated theirmore » cooking oil. Kaneclor 500 (a Japanese PCB mixture) contained in the heating pipe was used as the heat transmitter. Leakage of the pipe introduced PCBs and heat-degraded products such as polychlorinated dibenzofurans (PCDFs) and polychlorinated quaterphenyls (PCQs) into the rice oil. Exposed victims developed chloracne, hyperpigmentation, peripheral neuropathy, and other signs and symptoms which were later called Yu-Cheng ({open_quotes}oil disease{close_quotes}) in Taiwan. These symptoms were caused not only by PCBs but by their heat degraded products, PCDFs. PCBs, PCDFs and PCDDs also can cross the placenta to affect the fetus and cause significant neurodevelopmental toxicity. Raven`s Colored Progressive Matrices (CPM) and Standarized Progressive Matrices (SPM) test spatial rather than verbal capabilities in children. These test are useful for determining whether prenatal exposure to PCBs/PCDFs cause differential effects on boys and girls. This paper reports results of CPM and SPM from age six to nine year in Yu-Cheng children and their matched controls. Cognative deficits up to 9 years of age were detected n children with prenatal exposure to PCBs and PCDFs, and boys were more affected than girls. 26 refs., 1 fig., 2 tabs.« less

Dioxin formation from waste incineration.

PubMed

Shibamoto, Takayuki; Yasuhara, Akio; Katami, Takeo

2007-01-01

There has been great concern about dioxins-polychlorinated dibenzo dioxins (PCDDs), polychlorinated dibenzo furans (PCDFs), and polychlorinated biphenyls (PCBs)-causing contamination in the environment because the adverse effects of these chemicals on human health have been known for many years. Possible dioxin-contamination has received much attention recently not only by environmental scientists but also by the public, because dioxins are known to be formed during the combustion of industrial and domestic wastes and to escape into the environment via exhaust gases from incinerators. Consequently, there is a pressing need to investigate the formation mechanisms or reaction pathways of these chlorinated chemicals to be able to devise ways to reduce their environmental contamination. A well-controlled small-scale incinerator was used for the experiments in the core references of this review. These articles report the investigation of dioxin formation from the combustion of various waste-simulated samples, including different kinds of paper, various kinds of wood, fallen leaves, food samples, polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC), polyvinylidene chloride, polyethylene tetraphthalate (PET), and various kinds of plastic products. These samples were also incinerated with inorganic chlorides (NaCl, KCl, CuCI2, MgCl2, MnCl2, FeCl2, CoCl2, fly ash, and seawater) or organic chlorides (PVC, chlordane, and pentachlorophenol) to investigate the role of chlorine content and/or the presence of different metals in dioxin formation. Some samples, such as newspapers, were burned after they were impregnated with NaCl or PVC, as well as being cocombusted with chlorides. The roles of incineration conditions, including chamber temperatures, O2 concentrations, and CO concentrations, in dioxin formation were also investigated. Dioxins (PCDDs, PCDFs, and coplanar-PCBs) formed in the exhaust gases from a controlled small-scale incinerator, where experimental waste samples were burned, were analyzed by gas chromatography/mass spectrometry. Formation of total PCDFs was much higher than that of PCDDs in all samples. The total PCDFs comprised 70%-90% of the total dioxin formed. The amount of total PCDFs formed ranged from 0.78 ng/g (newspaper) to 8,490ng/g (PVC burned in high CO concentration). The amount of total PCDDs formed ranged from 0.02ng/g (newspaper) to 430ng/g (PVC). Coplanar PCBs were found at the lowest level of the dioxins formed. Their formation levels ranged from 0ng/g (newspaper) to 77.6ng/g (PVC). It is obvious that the samples with either inorganic or organic chlorides produced much more dioxins than the sample without chlorides when incinerated under similar conditions. It is not clear how inorganic and organic chloride contribute differently to dioxin formation. Among the metals examined, copper seems to have higher activity toward dioxin formation than other metals. It acted not only as a catalyst but also as a transmitter of heterogeneous chlorine. The toxicity equivalence quantity (TEQ) values generally correlated with the amount of chlorine content in the samples and the amount of dioxin formed in exhaust gases from an incinerator. When the same sample was incinerated at different temperatures, however, the sample burned at low temperature yielded a higher TEQ value than did the sample burned at high temperature. The samples that did not contain chlorine or were not combusted with chlorides exhibited low TEQ values. In contrast, samples with high chlorine content, such as PVC (51.3%), gave high TEQ values. Combustion temperatures may play an important role in dioxin formation in exhaust gases from the incineration of waste materials. However, no significant relationship between dioxin formation and chamber temperatures was reported in the core articles. However, It is obvious that dioxin formation occurred at temperatures above 450'C and was reduced significantly at temperatures above 850 degrees C. The reaction occurring in an incinerator is extremely complex, and there are many factors in addition to combustion temperature influencing dioxin formation. Even though it is possible to hypothesize reasonable formation mechanisms of dioxins produced in exhaust gases according to the results obtained from experiments in classical chemistry, the reactions involved in an incinerator are extremely complex and heterogeneous. More detailed investigation of the many individual factors influencing dioxin formation is needed to find ways to reduce their formation in individual and municipal incinerators.

Multiple lines of evidence risk assessment of American robins exposed to polychlorinated dibenzofurans (PCDFS) and polychlorinated dibenzo-P-dioxins (PCDDS) in the Tittabawassee River floodplain, Midland, Michigan, USA.

PubMed

Tazelaar, Dustin L; Fredricks, Timothy B; Seston, Rita M; Coefield, Sarah J; Bradley, Patrick W; Roark, Shaun A; Kay, Denise P; Newsted, John L; Giesy, John P; Bursian, Steven J; Zwiernik, Matthew J

2013-06-01

Concentrations of polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzo-p-dioxins (PCDDs) in Tittabawassee River floodplain soils and biota downstream of Midland, Michigan, USA, are greater than regional background concentrations. From 2005 to 2008, a multiple lines of evidence approach was utilized to evaluate the potential for effects of PCDD/DFs on American robins (Turdus migratorius) breeding in the floodplains. A dietary-based assessment indicated there was potential for adverse effects for American robins predicted to have the greatest exposures. Conversely, a tissue-based risk assessment based on site-specific PCDD/DF concentrations in American robin eggs indicated minimal potential for adverse effects. An assessment based on reproductive endpoints indicated that measures of hatch success in study areas were significantly less than those of reference areas. However, there was no dose-response relationship between that endpoint and concentrations of PCDD/DF. Although dietary-based exposure and reproductive endpoint assessments predicted potential for adverse effects to resident American robins, the tissue-based assessment indicates minimal to no potential for adverse effects, which is reinforced by the fact the response was not dose related. It is likely that the dietary assessment is overly conservative given the inherent uncertainties of estimating dietary exposure relative to direct tissue-based assessment measures. Based on the available data, it can be concluded that exposure to PCDD/DFs in the Tittabawassee River floodplain would not likely result in adverse population-level effects to American robins. Copyright © 2013 SETAC.

Chemical contaminants in fish feeds used in federal salmonid hatcheries in the USA

USGS Publications Warehouse

Maule, A.G.; Gannam, A.L.; Davis, J.W.

2007-01-01

Recent studies have demonstrated that fish feeds contain significant concentrations of contaminants, many of which can bioaccumulate and bioconcentrate in fish. Organochlorine (OC) contaminants are present in the fish oils and fish meals used in feed manufacture, and some researchers speculate that all fish feeds contain measurable levels of some contaminants. To determine the concentration of contaminants in feeds used in US Fish and Wildlife Service's National Fish Hatcheries, we systematically collected samples of feed from 11 cold-water fish hatcheries. All samples (collected from October 2001 to October 2003) contained at least one polychlorinated dibenzo-p-dioxin (PCDD), polychlorinated dibenzofuran (PCDF), polychlorinated biphenyl (PCB) congener, or dichlorodiphenyltrichloroethane (DDT) metabolite. Of the 55 samples in which they were analyzed 39 contained PCDDs, 24 contained PCDFs and 24 contained DDT or its metabolites. There were 10- to 150-fold differences in concentrations of total PCBs, PCDDs, PCDFs and DDT. Although PCBs were the most commonly detected contaminant in our study, concentrations (range: 0.07-10.46 ng g-1 wet weight) were low compared to those reported previously. In general, we also found lower levels of OCs than reported previously in fish feed. Perhaps most notable was the near absence of OC pesticides - except for DDT or its metabolites, and two samples containing hexachlorocyclohexane (HCH). While contaminant concentrations were generally low, the ecological impacts can not be determined without a measure of the bioaccumulation of these compounds in the fish and the fate of these compounds after the fish are released. ?? 2006 Elsevier Ltd. All rights reserved.

Toxic equivalency factors (TEFs) for PCBs, PCDDs, PCDFs for humans and wildlife

USGS Publications Warehouse

Van Den, Berg; Birnbaum, L.; Bosveld, A.T.C.; Brunstrom, B.; Cook, P.; Feeley, M.; Giesy, J.P.; Hanberg, A.; Hasegawa, R.; Kennedy, S.W.; Kubiak, T.; Larsen, J.C.; Van Leeuwen, F. X. R.; Liem, A.K.D.; Nolt, C.; Peterson, R.E.; Poellinger, L.; Safe, S.; Schrenk, D.; Tillitt, D.; Tysklind, M.; Younes, M.; Waern, F.; Zacharewski, T.

1998-01-01

An expert meeting was organized by the World Health Organization (WHO) and held in Stockholm on 15-18 June 1997. The objective of this meeting was to derive consensus toxic equivalency factors (TEFs) for polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and dioxinlike polychlorinated biphenyls (PCBs) for both human, fish, and wildlife risk assessment. Based on existing literature data, TEFs were (re)evaluated and either revised (mammals) or established (fish and birds). A few mammalian WHO-TEFs were revised, including 1,2,3,7,8-pentachlorinated DD, octachlorinated DD, occachlorinated DF, and PCB 77. These mammalian TEFs are also considered applicable for humans and wild mammalian species. Furthermore, it was concluded that there was insufficient in vivo evidence to continue the use of TEFs for some di-ortho PCBs, as suggested earlier by Ahlborg et al. In addition, TEFs for fish and birds were determined. The WHO working group attempted to harmonize TEFs across different taxa to the extent possible. However, total synchronization of TEFs was not feasible, as there were orders of a magnitude difference in TEFs between taxa for some compounds. In this respect, the absent or very low response of fish to mono-ortho PCBs is most noticeable compared to mammals and birds. Uncertainties that could compromise the TEF concept were also reviewed, including nonadditive interactions, differences in shape of the dose-response curve, and species responsiveness. In spite of these uncertainties, it was concluded that the TEF concept is still the most plausible and feasible approach for risk assessment of halogenated aromatic hydrocarbons with dioxinlike properties.

PCDD/Fs and PCBs in seafood species from Moreton Bay, Queensland, Australia.

PubMed

Matthews, V; Päpke, O; Gaus, C

2008-01-01

Previous studies have identified elevated levels of polychlorinated dibenzo-p-dioxins (PCDDs) in sediments and megafauna (dugongs and green turtles) in the marine environment of southeast Queensland, Australia. Little information exists, however, regarding the levels of PCDDs, polychlorinated dibenzofurans (PCDFs) and related polychlorinated biphenyls (PCBs) in seafood from this area. This study aims to establish baseline information on PCDD/F and PCB contamination in a range of seafood species from Moreton Bay and to investigate contaminant variability due to harvesting season, size, habitat location and trophic level. In addition, different seafood extraction methods were tested to evaluate their impact on lipid yields and contaminant concentration. Overall, the median TEQ(DF&PCB) levels in seafood from Moreton Bay were elevated compared to background levels in Australian marine/estuarine and retail fish. However, TEQ(DF&PCB) levels of most seafood analysed were below the respective EU maximum limits. High inter- and intraspecies variability was observed, which could be partially attributed to differences in trophic level, season harvested and habitat location.

Binding effect of polychlorinated compounds and environmental carcinogens on rice bran fiber.

PubMed

Sera, Nobuyuki; Morita, Kunimasa; Nagasoe, Masami; Tokieda, Hisako; Kitaura, Taeko; Tokiwa, Hiroshi

2005-01-01

To accelerate the fecal excretion of polycyclic biphenyl (PCB), polychlorinated dibenzofurans (PCDFs), polychlorinated-p-dioxines (PCDDs) and various mutagens and carcinogens, their binding effect on rice bran fiber (RBF) was investigated for nine heterocyclic amines, six nitroarenes, 4-nitroquinoline-N-oxide, benzo[a]pyrene, furylfuramide, two kinds of flavonoid compounds and formaldehyde and ascorbic acid. PCBs, PCDFs and PCDDs suspended in nonane were incubated with RBF (10 mg/ml) at 37 degrees C and after centrifugation, unbound chemicals in the supernatant were analyzed by high-performance liquid chromatography (HPLC) and gas chromatography (GC). The binding effects on RBF were enhanced more than other dietary fibers (DFs), which were tested including corn, wheat bran, spinach, Hijiki (a kind of seaweed), sweet potatoes and burdock fibers. It was found that the binding effects were related to lignin contents. Binding of 3-amino-1(or 1,4)-dimethyl-5H-pyrido[4,3-b]indole (Trp-p-1 and Trp-p-2), food-derived carcinogens and 1-nitropyrene (1-NP), suspended in methanol, to RBF occurred within 10 min of incubation at 37 degrees C at pH 5-7, and decreased below pH 4; binding of food-derived carcinogens was pH dependent. The binding effects to RBF and pulp lignin were obtained at ratio of over 90%, while corn fiber and cellulose were at ratios of 4-30%. Polycyclic aromatic compounds were related to the number of rings, showing high binding effects to chemical structures with triple rings. Binding of 1-NP and PCB to RBF was not influenced in any aerobic and anaerobic bacterial cultures. It was also found that RBF was capable of binding even conjugates containing mutagens such as glucuronides and sulfates, as well as metabolites in urine. It was suggested, therefore, that mutagens and carcinogens were available for the fecal excretion of residual chemicals and their metabolites, and also for the fecal excretion of PCBs, PCDFs and related compound residues in patients of Yusho disease, who suffered food poisoning due to rice oil contaminated with PCB in Japan.

Combining NMR spectral and structural data to form models of polychlorinated dibenzodioxins, dibenzofurans, and biphenyls binding to the AhR

NASA Astrophysics Data System (ADS)

Beger, Richard D.; Buzatu, Dan A.; Wilkes, Jon G.

2002-10-01

A three-dimensional quantitative spectrometric data-activity relationship (3D-QSDAR) modeling technique which uses NMR spectral and structural information that is combined in a 3D-connectivity matrix has been developed. A 3D-connectivity matrix was built by displaying all possible assigned carbon NMR chemical shifts, carbon-to-carbon connections, and distances between the carbons. Two-dimensional 13C-13C COSY and 2D slices from the distance dimension of the 3D-connectivity matrix were used to produce a relationship among the 2D spectral patterns for polychlorinated dibenzofurans, dibenzodioxins, and biphenyls (PCDFs, PCDDs, and PCBs respectively) binding to the aryl hydrocarbon receptor (AhR). We refer to this technique as comparative structural connectivity spectral analysis (CoSCoSA) modeling. All CoSCoSA models were developed using forward multiple linear regression analysis of the predicted 13C NMR structure-connectivity spectral bins. A CoSCoSA model for 26 PCDFs had an explained variance (r2) of 0.93 and an average leave-four-out cross-validated variance (q4 2) of 0.89. A CoSCoSA model for 14 PCDDs produced an r2 of 0.90 and an average leave-two-out cross-validated variance (q2 2) of 0.79. One CoSCoSA model for 12 PCBs gave an r2 of 0.91 and an average q2 2 of 0.80. Another CoSCoSA model for all 52 compounds had an r2 of 0.85 and an average q4 2 of 0.52. Major benefits of CoSCoSA modeling include ease of development since the technique does not use molecular docking routines.

Polychlorinated dibenzo-p-dioxins, dibenzofurans, biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents in fishes from Saginaw Bay, Michigan

USGS Publications Warehouse

Giesy, John P.; Jude, David J.; Tillitt, Donald E.; Gale, Robert W.; Meadows, John C.; Zajieck, James L.; Peterman, Paul H.; Verbrugge, David A.; Sanderson, J. Thomas; Schwartz, Ted R.; Tuchman, Marc L.

1997-01-01

Concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated naphthalenes (PCNs), polychlorinated dibenzothiophenes (PCDTs), and 2,3,7,8-tetrachlo-rodibenzo-p-dioxin (2,3,7,8-TCDD) equivalents were measured in composite samples of forage fishes and several sizes of walleyes (Stizostedion vitreum) and common carp (Cyprinus carpio) collected from Saginaw Bay, Michigan, USA. The concentrations of 2,3,7,8-TCDD equivalents determined from the use of TCDD equivalency factors (TEFs) and instrumentally determined concentrations of individual congeners were designated TEq. The 2,3,7,8-TCDD equivalents determined on the same extracts with the H4IIE bioassay were defined as TCDD-EQ. Concentrations of TCDD-EQ and TEq were significantly, but poorly correlated (R2 = 0.44). Concentrations of TCDD-EQ and TEq ranged from 10.6 to 348 and 13.5 to 69.5 ng/kg, wet weight, respectively. The ratio of TCDD-EQ to TEq ranged from 0.5 to 5.0, with the greatest ratio observed in common carp but the average ratio between TEq and TCDD-EQ was approximately 1.0. In common carp, larger walleye, and medium-sized alewife (Alosa pseudoharengus) there were significant concentrations of TCDD-EQ that could not be accounted for by TEq calculated from an additive model of PCBs, PCDDs, or PCDFs. As much as 75% of the TCDD-EQ in some samples could not be accounted for by TEqs. It is unlikely that PCNs, PCDTs, or polychlorinated diphenyl ethers (PCDEs) occurred at concentrations that were, based on their relative potencies, great enough to contribute significant quantities of TCDD-EQ. The discrepency between TCDD-EQs and TEqs was not due to antagonisms among congeners or extraction efficiencies.

Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like coplanar polychlorinated biphenyls in mackerel obtained from the Japanese market, 1999-2003.

PubMed

Nakatani, Tadashi; Yamano, Testuo

2017-09-01

This study analysed the concentrations and toxic-equivalent (TEQ) levels of dioxin congeners in mackerel commercially available in Japan in early 2000s. The content of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like coplanar polychlorinated biphenyls (DL-PCBs) was determined in 17 mackerel samples from different areas. TEQ levels in mackerel muscle were 0.78 pg TEQ g - 1 wet weight (wt) on average (range = 0.21-2.26 pg TEQ g - 1 wet wt) for PCDD/Fs (PCDDs plus PCDFs), 2.81 pg TEQ g - 1 wet wt on average (range = 1.02-8.5 pg TEQ g - 1 wet wt) for DL-PCBs, and 3.59 pg TEQ g - 1 wet wt on average (range = 1.24-10.8 pg g - 1 wet wt) for dioxins (PCDD/Fs plus DL-PCBs). The results revealed somewhat higher TEQ levels for dioxins compared with the other data for fish and shellfish in the Japanese market. TEQ levels were well correlated with mackerel body weight; the main contributors were tetra- and penta-CDD/Fs, some hexa-CDD/Fs, and all 12 DL-PCBs, which are known to have high bioaccumulation potential. In particular, PCB 126 was mostly responsible for the observed correlation of DL-PCB and dioxins-TEQ levels with mackerel body weight. The average daily intake of dioxins in terms of TEQ through mackerel consumption was estimated to be 4.81 pg TEQ/person/day, accounting for 7% of the total intake of dioxins-TEQ through fish and shellfish in Japan.

Relationship of polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran levels to stable-nitrogen isotope abundance in marine birds and mammals in coastal California

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

Jarman, W.M.; Sydeman, W.J.; Hobson, K.A.

1997-05-01

Levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in common murre (Uria aalge), Brandt`s cormorant (Phalacrocorax penicillatus), rhinoceros auklet (Cerorhinca monocerata), and pigeon guillemot (Cepphus columba) eggs, and Steller sea lion (Eumetopias jubatus) blubber collected from the Gulf of the Farallones National Marine Sanctuary in 1993. In addition, the samples were analyzed for stable-nitrogen isotopes ({delta}{sup 15}N). Of the PCDDs and PCDFs, the 2,3,7,8-TCDD (TCDD) and 2,3,7,8-TCDF (TCDF) congeners were the most prominent in the birds. The levels of TCDD in the eggs ranged from 0.2 to 6.6 ng/wet kg in the pigeon guillemot and Brandt`s cormorant,more » respectively. The TCDF ranged from 0.30 to 2.25 ng/kg in the pigeon guillemot and Brandt`s cormorant eggs, respectively. Other prominent PCDD and PCDF congeners detected in all bird species were 1,2,3,6,7,8-HxCDD, 2,3,4,7,8-PeCDF, 1,2,3,7,8-PeCDD and 1,2,3,4,6,7,8-HpCDD. In the Steller sea lion the most prominent congeners were 1,2,3,7,8-PeCDD at 3.2 ng/kg, 2,3,7,8-TCDD at 2.9 ng/kg, OCDF at 2.2 ng/kg, 1,2,3,6,7,8-HxCDD at 1.92 ng/kg, and 1,2,3,4,7,8-HxCDF at 1.3 ng/kg. Stable-nitrogen values ranged from 16.9% in the pigeon guillemot and rhinoceros auklet to 19.8% in the Steller sea lion.« less

Environmental contaminants in male river otters from Oregon and Washington, USA, 1994-1999

USGS Publications Warehouse

Grove, R.A.; Henny, C.J.

2008-01-01

This study reports hepatic concentrations and distribution patterns of select metals, organochlorine pesticides (OCs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in 180 male river otters (Lontra canadensis) collected from Oregon and Washington, 1994-1999. Seven regional locations of western Oregon and Washington were delineated based on associations with major population centers, industry or agriculture. Cadmium (Cd) was not found above 0.5 ??g g-1, dry weight (dw) in juveniles, but increased with age in adults though concentrations were generally low (nd-1.18 ??g g-1, dw). Regional geometric means for total mercury (THg) ranged from 3.63 to 8.05 ??g g-1, dw in juveniles and 3.46-2.6 ??g g-1 (dw) in adults. The highest THg concentration was 148 ??g g-1, dw from an apparently healthy adult male from the Olympic Peninsula of Washington. Although THg increased with age in adult otters, the occurrence of the more toxic form methylmercury (MeHg) was not evaluated. Mean OC and PCB concentrations reported in this study declined dramatically from those reported in 1978-1979 from the lower Columbia River. Organochlorine pesticide and metabolite means for both juvenile and adult river otter males were all below 100 ??g kg-1, wet weight (ww), with only DDE, DDD and HCB having individual concentrations exceeding 500 ??g kg-1, ww. Mean ??PCB concentrations in both juvenile and adult male otters were below 1 ??g g-1 for all regional locations. Mean juvenile and adult concentrations of non-ortho substituted PCBs, PCDDs and PCDFs were in the low ng kg-1 for all locations studied. ?? Springer Science+Business Media B.V. 2007.

PCDDs/PCDFs, PCBs, and organochlorine pesticides in eggs of Eurasian sparrowhawks (Accipiter nisus), hobbies (Falco subbuteo), and northern goshawks (Accipiter gentilis) collected in the area of Berlin-Brandenburg, Germany.

PubMed

Wiesmüller, T; Sömmer, P; Volland, M; Schlatterer, B

2002-05-01

Concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and organochlorine (OC) pesticides were measured in unsuccessfully hatched eggs of three different kinds of predatory birds: 3 eggs of sparrowhawks, 7 eggs of hobbies, and 16 eggs of goshawks collected in the German region of Berlin-Brandenburg. Using toxic equivalency factors for birds, eggs of hobbies contained mean concentrations of 478 pg TEQ/g fat and 551 pg TEQ/g fat contributed by PCDD/Fs and coplanar PCBs, respectively. For sparrowhawks the respective TCDD equivalents were 424 and 1278 pg/g fat; those for goshawks were 211 and 935 pg/g fat. The mean value of the summed concentrations of the PCB congeners 28, 52, 101, 138, 153, and 180 amounted to 11 microg/g fat in eggs of hobbies, 9.5 microg/g fat for sparrowhawks, and 16.1 microg/g fat for goshawks. Of the analyzed organochlorine pesticides the concentration of p,p'-DDE was highest (up to 273 microg/g); the concentration of the other OCs, with the exception of methoxychlor in eggs of goshawks (highest level of 10.6 microg/g fat), were negligible. In all cases the calculated toxicity of the coplanar PCBs surpassed the toxicity of the PCDD/Fs, at least by a factor of two. Due to the higher concentration of the coplanar PCB 77 compared to PCB 126 in eggs of hobbies, it is concluded that its metabolic excretion in this species is much lower than in sparrowhawks and goshawks.

Analyses of known and new types of polyhalogenated aromatic substances in oven ash from recycled aluminium production.

PubMed

Sinkkonen, Seija; Lahtiperä, Mirja; Vattulainen, Antero; Takhistov, Viatcheslav V; Viktorovskii, Igor V; Utsal, Viktor A; Paasivirta, Jaakko

2003-07-01

Persistent aromatic bromine, chlorine and mixed chlorine-bromine compounds were analysed from recycled aluminium smelter (ALS) ashes to explore the impact of brominated flame retardants (BFR) on their formation. Polybrominated diphenyl ethers (PBDE) were the most abundant original BFRs found. Induction furnace ash contained tetra- to octa-BDEs about 2000ng g(-1) in similar congener ratios as the original scrap, but contents of nona- and deca-BDEs were only 25 and 5ng g(-1) indicating their significant degradation in ALS process. In the most non-polar fraction, PCB levels and profiles were similar as earlier ALS ash samples in 1990s. The highest PCB level measured was that of deca-CB (450ng g(-1)) in the induction furnace ash. In this fraction, bromo compounds were non-detectable (<5ng g(-1)). Fraction of the most polar compounds (from reversed toluene elution of carbon column ("dioxin fraction") contained PCDDs, PCDFs and polychlorinated dibenzothiophenes (PCDTs) in similar amounts and congener profiles as earlier investigated ALS ash samples. Bromine-containing dioxin and furan congeners were not detected. From individual PCDDs and PCDFs, octaCDF was the most abundant (205ng g(-1)) in induction furnace ash. In this fraction, the original BFR, tetrabromo-bisphenol-A, was identified. Its level in the induction furnace ash was approximated to be 388ng g(-1). In addition, 12 novel brominated and chlorinated compounds were found as abundant (8-441ng g(-1) in the induction furnace ash) contaminants from the fraction. Four of them were bisphenol derivatives, five biphenylols, then octachlorofluorenone (OCFL) and octachlorobiphenylene (OCBP). Their structures or structure types were deduced from total low-resolution EI mass spectra by theoretical isotope cluster simulation (ICLU) and through known fragmentation rules.

Highly purified hexachlorobenzene induces cytochrome P4501A in primary cultures of chicken embryo hepatocytes

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

Mundy, Lukas J.; Environment Canada, National Wildlife Research Centre, Ottawa, Ontario; Jones, Stephanie P.

Some uncertainty exists regarding the purity of hexachlorobenzene (HCB) used in past toxicity studies. It has been suggested that reported toxic and biochemical effects initially attributed to HCB exposure may have actually been elicited by contamination of HCB by polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Herein, primary cultures of chicken embryo hepatocytes (CEH) were used to compare the potencies of two lots of reagent-grade hexachlorobenzene (HCB-old [HCB-O] and HCB-new [HCB-N]), highly purified HCB (HCB-P) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as inducers of ethoxyresorufin O-deethylase (EROD) activity, cytochrome P4501A4 (CYP1A4) messenger ribonucleic acid (mRNA) and CYP1A5 mRNA. The study also compared themore » EROD- and CYP1A4/5 mRNA-inducing potencies of HCB to the potencies of two mono-ortho substituted polychlorinated biphenyls (PCBs), 2,3,3',4,4'-pentachlorobiphenyl (PCB 105) and 2,3'4,4',5-pentachlorobiphenyl (PCB 118). HCB-O, HCB-N and HCB-P all induced EROD activity and up-regulated CYP1A4 and CYP1A5 mRNAs. Induction was not caused by contamination of HCB with PCDDs or PCDFs. Based upon a comparison of the EC{sub 50} and EC{sub threshold} values for EROD and CYP1A4/5 mRNA concentration-response curves, the potency of HCB relative to the potency of TCDD was 0.0001, and was similar to that of PCB 105 and PCB 118. The maximal EROD activity and CYP1A4/5 mRNA expression differed greatly between HCB and TCDD, and may contribute to an overestimation of the ReP value calculated for highly purified HCB.« less

The effects of fuel composition and ammonium sulfate addition on PCDD, PCDF, PCN and PCB concentrations during the combustion of biomass and paper production residuals.

PubMed

Lundin, Lisa; Jansson, Stina

2014-01-01

The use of waste wood as an energy carrier has increased during the last decade. However, the higher levels of alkali metals and chlorine in waste wood compared to virgin biomass can promote the formation of deposits and organic pollutants. Here, the effect of fuel composition and the inhibitory effects of ammonium sulfate, (NH4)2SO4, on the concentrations of persistent organic pollutants (POPs) in the flue gas of a lab-scale combustor was investigated. Ammonium sulfate is often used as a corrosion-preventing additive and may also inhibit formation of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). In addition to PCDDs and PCDFs, polychlorinated naphthalenes (PCN) and biphenyls (PCB) were also analyzed. It was found that the flue gas composition changed dramatically when (NH4)2SO4 was added: CO, SO2, and NH3 levels increased, while those of HCl decreased to almost zero. However, the additive's effects on POP formation were less pronounced. When (NH4)2SO4 was added to give an S:Cl ratio of 3, only the PCDF concentration was reduced, indicating that this ratio was not sufficient to achieve a general reduction in POP emissions. Conversely, at an S:Cl ratio of 6, significant reductions in the WHO-TEQ value and the PCDD and PCDF contents of the flue gas were observed. The effect on the PCDF concentration was especially pronounced. PCN formation seemed to be promoted by the elevated CO concentrations caused by adding (NH4)2SO4. Copyright © 2013. Published by Elsevier Ltd.

Occurrence of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) in eggs from free-range hens in Campania (southern Italy) and risk evaluation.

PubMed

Lambiase, Sara; Serpe, Francesco Paolo; Cavallo, Stefania; Rosato, Guido; Baldi, Loredana; Neri, Bruno; Esposito, Mauro

2017-01-01

Hens' eggs collected in home-producing farms located in different areas of the Campania region of southern Italy were analysed for six NDL-polychlorobiphenyls (PCB indicators), 17 polychlorodibenzo-p-dioxins (PCDDs) and polychlorodibenzofurans (PCDFs), and 12 congeners of dioxin-like PCBs (DL-PCBs). In the investigated area, waste from civil, industrial and hospital activities was illegally dumped and in many cases burned, so the area is called the 'Land of fire'. This illicit practice has been considered the main source of pollution in this territory and the cause of the persistent organic pollutants' (POPs) contamination in the neighbouring lands intended for agricultural use and livestock. The results, which were obtained from the analysis of 56 samples of eggs, showed levels of contamination by dioxins and PCBs that have often exceeded the action levels set by European Union Recommendation 711/2013 and sometimes even exceeded the maximum levels set by Commission Regulation (EU) 1259/2011. The median PCDD/Fs was 0.41 pg TEQ g -1 fat (range = 0.01-6.18 pg TEQ g -1 fat) and the median concentration of DL-PCBs was 0.70 pg TEQ g -1 fat (range = 0.01-14.60 pg TEQ g -1 fat), whereas NDL-PCBs median was 7.35 ng g -1 fat (range = 0.48-67.55 ng g -1 fat). Nevertheless, the estimated weekly intake (EWI) calculated for consumers of eggs home produced in Campania is lower than the tolerable weekly intake (TWI) established by the European Union Scientific Committee on Food (SCF).

Highly chlorinated unintentionally produced persistent organic pollutants generated during the methanol-based production of chlorinated methanes: A case study in China.

PubMed

Zhang, Lifei; Yang, Wenlong; Zhang, Linli; Li, Xiaoxiu

2015-08-01

The formation of unintentionally produced persistent organic pollutants (POPs) may occur during various chlorination processes. In this study, emissions of unintentionally produced POPs during the methanol-based production of chlorinated methanes were investigated. High concentrations of highly chlorinated compounds such as decachlorobiphenyl, octachloronaphthalene, octachlorostyrene, hexachlorobutadiene, hexachlorocyclopentadiene, hexachlorobenzene, and pentachlorobenzene were found in the carbon tetrachloride byproduct of the methanol-based production of chlorinated methanes. The total emission amounts of hexachlorocyclopentadiene, hexachlorobutadiene, polychlorinated benzenes, polychlorinated naphthalenes, octachlorostyrene, and polychlorinated biphenyls released during the production of chlorinated methanes in China in 2010 were estimated to be 10080, 7350, 5210, 427, 212, and 167 kg, respectively. Moreover, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) were formed unintentionally during chlorinated methanes production, the emission factor for PCDDs/DFs was 364 μg toxic equivalency quotient (TEQ) t(-1) product for residues, which should be added into the UNEP toolkit for updating. It was worth noting that a high overall toxic equivalency quotient from polychlorinated naphthalenes and PCDDs/DFs was generated from the chlorinated methanes production in China in 2010. The values reached 563 and 32.8 g TEQ, respectively. The results of the study indicate that more research and improved management systems are needed to ensure that the methanol-based production of chlorinated methanes can be achieved safely. Copyright © 2015 Elsevier Ltd. All rights reserved.

Emissions of PCDD/Fs in flue gas from a medical waste incinerator in Shanghai

NASA Astrophysics Data System (ADS)

He, Jiao; Liu, Tao; Qiang, Ning; Li, Zhaohai; Cao, Yiqi; Xie, Li; Zhao, Yuanchen

2017-12-01

Emission characteristics of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and 17 congeners from a medical waste incineration plants in Shanghai, China were investigated. Results showed that the dioxin concentration ranged from 5.0 to 23.3ng I-TEQ (Toxic Equivalent Quantity) Nm-3 under normal combustion concentration. The high dioxin incidence area was found in the boiler outlet and the bag filter inlet, and over 95% of the dioxins were present in the gaseous state. Polychlorinated dibenzofurans (PCDFs) accounted for a higher proportion of the total amount of PCDD/Fs than polychlorinated dibenzo-p-dioxins (PCDDs).

Theoretical Mechanistic and Kinetic Studies on Homogeneous Gas-Phase Formation of Polychlorinated Naphthalene from 2-Chlorophenol as Forerunner

PubMed Central

Xu, Fei; Zhang, Ruiming; Li, Yunfeng; Zhang, Qingzhu; Wang, Wenxing

2015-01-01

Polychlorinated naphthalenes (PCNs) are dioxins-like compounds and are formed along with polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in thermal and combustion procedures. Chlorophenols (CPs) are the most important forerunners of PCNs. A comprehensive comprehension of PCN formation procedure from CPs is a precondition for reducing the discharge of PCNs. Experiments on the formation of PCNs from CPs have been hindered by PCN toxicity and short of precise detection methods for active intermediate radicals. In this work, PCN formation mechanism in gas-phase condition from 2-chlorophenol (2-CP) as forerunner was studied by quantum chemistry calculations. Numbers of energetically advantaged formation routes were proposed. The rate constants of key elementary steps were calculated over 600–1200 K using canonical variational transition-state theory (CVT) with small curvature tunneling contribution (SCT) method. This study illustrates formation of PCNs with one chlorine atom loss from 2-CP is preferred over that without chlorine atom loss. In comparison with formation of PCDFs from 2-CP, PCN products are less chlorinated and have lower formation potential. PMID:26516839

Theoretical Mechanistic and Kinetic Studies on Homogeneous Gas-Phase Formation of Polychlorinated Naphthalene from 2-Chlorophenol as Forerunner.

PubMed

Xu, Fei; Zhang, Ruiming; Li, Yunfeng; Zhang, Qingzhu; Wang, Wenxing

2015-10-26

Polychlorinated naphthalenes (PCNs) are dioxins-like compounds and are formed along with polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in thermal and combustion procedures. Chlorophenols (CPs) are the most important forerunners of PCNs. A comprehensive comprehension of PCN formation procedure from CPs is a precondition for reducing the discharge of PCNs. Experiments on the formation of PCNs from CPs have been hindered by PCN toxicity and short of precise detection methods for active intermediate radicals. In this work, PCN formation mechanism in gas-phase condition from 2-chlorophenol (2-CP) as forerunner was studied by quantum chemistry calculations. Numbers of energetically advantaged formation routes were proposed. The rate constants of key elementary steps were calculated over 600-1200 K using canonical variational transition-state theory (CVT) with small curvature tunneling contribution (SCT) method. This study illustrates formation of PCNs with one chlorine atom loss from 2-CP is preferred over that without chlorine atom loss. In comparison with formation of PCDFs from 2-CP, PCN products are less chlorinated and have lower formation potential.

Bioaccumulation of organochlorines in crows from an indian open waste dumping site: evidence for direct transfer of dioxin-like congeners from the contaminated soil.

PubMed

Watanabe, Michio X; Iwata, Hisato; Watanabe, Mafumi; Tanabe, Shinsuke; Subramanian, Annamalai; Yoneda, Kumiko; Hashimoto, Takuma

2005-06-15

To assess the significance of waste dumping sites as a source of chemical contamination to ecosystems, we analyzed the residue levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and other organochlorines in the breast muscle of crows from a dumping site in the south of Chennai city, South India. Crows from the dumping site contained significantly higher total TEQs (60 +/- 27 pg/g lipid wt) than those from the reference sites (26 +/- 18 pg/g lipid wt). Especially, certain dioxin-like coplanar PCB congeners (Co-PCBs), such as CB-77 and CB-105, whose source is commercial PCBs,were significantly higher in crows from the dumping site than those from the reference sites. Profiles of PCDDs/DFs and Co-PCBs in crows from the dumping site were similar to those of soil at the same site, which was confirmed by principal component analysis. Furthermore, significant positive correlations were obtained between the congener-specific bioconcentration factors (BCFs) of PCDDs/DFs estimated from concentrations in crows and soil from the dumping site and the theoretical BCFs calculated from water-particle and lipid-water partitioning coefficients. On the other hand, the estimated BCFs had significant negative correlations with the molecular weight of PCDDs/DFs, indicating that molecular size limits their bioaccumulation. These results suggest that dioxin-like congeners in the soil of the dumping site were transferred directly to the crows through the ingestion of on-site garbage contaminated with soil, rather than through trophic transfer in the ecosystem. The present study provides insight into the ecological impacts of dumping sites.

Contaminants in ospreys from the Pacific Northwest: I. Trends and Patterns in polychlorinated dibenzo-p-dioxins and -dibenzofurans in eggs and plasma

USGS Publications Warehouse

Elliott, J.E.; Machmer, M.M.; Henny, Charles J.; Wilson, L.K.; Norstrom, R.J.

1998-01-01

Osprey (Pandion haliaetus) eggs were collected from 1991 to 1997 at nests (na??=a??121) upstream and downstream of bleached kraft pulp mills and at reference sites in the Fraser and Columbia River drainage systems of British Columbia, Washington, and Oregon. Blood samples were collected from nestling ospreys during the 1992 breeding season on the Thompson River. Samples were analyzed for polychlorinated dibenzo-p-dioxins (PCDDs) and -dibenzofurans (PCDFs). Mean concentrations of 2,3,7,8-TCDD were significantly higher in eggs collected in 1991 at downstream compared to upstream nests near pulp mills at Kamloops and Castlegar, British Columbia. There were no significant temporal trends in 2,3,7,8-TCDD, -TCDF or other measured compounds at a sample of nests monitored between 1991 and 1994 downstream of the Castlegar pulp mill, despite changes in bleaching technology (CIO2 substitution). However, by 1997 concentrations of 2,3,7,8-TCDD and -TCDF were significantly lower than previous years in nests sampled downstream at both Castlegar and Kamloops. An unusual pattern of higher chlorinated PCDDs and PCDFs was found in many of the osprey eggs collected in this study, and considerable individual variation in the pattern existed among eggs from the same site. For example, eggs from four different nests at one study area (Quesnel) on the Fraser River had concentrations of 1,2,3,4,6,7,8-HpCDD ranging from <1 to 1,100 ng/kg and OCDD from <1 to 7,000 ng/kg wet weight. Higher mean concentrations of HpCDD and OCDD were found in eggs from the Thompson River, a tributary of the Fraser, compared to the Columbia River, and concentrations were generally higher at nests upstream of pulp mills. In plasma samples, 1,2,3,4,6,7,8-HpCDD and OCDD were the main compounds detected, with no significant differences measured between samples upstream versus downstream or earlier versus later in the breeding season. Use of chlorophenolic wood preservatives by lumber processors was considered the main source of higher chlorinated PCDD/Fs throughout the systems, based on patterns of trace PCDFs in eggs and significant correlations between egg concentrations of pentachlorophenol and both HpCDD (ra??=a??0.891, pa??

Contaminants in ospreys from the Pacific Northwest: I. Trends and patterns in polychlorinated dibenzo-p-dioxins and -dibenzofurans in eggs and plasma.

PubMed

Elliott, J E; Machmer, M M; Henny, C J; Wilson, L K; Norstrom, R J

1998-11-01

Osprey (Pandion haliaetus) eggs were collected from 1991 to 1997 at nests (n = 121) upstream and downstream of bleached kraft pulp mills and at reference sites in the Fraser and Columbia River drainage systems of British Columbia, Washington, and Oregon. Blood samples were collected from nestling ospreys during the 1992 breeding season on the Thompson River. Samples were analyzed for polychlorinated dibenzo-p-dioxins (PCDDs) and -dibenzofurans (PCDFs). Mean concentrations of 2,3,7,8-TCDD were significantly higher in eggs collected in 1991 at downstream compared to upstream nests near pulp mills at Kamloops and Castlegar, British Columbia. There were no significant temporal trends in 2,3,7,8-TCDD, -TCDF or other measured compounds at a sample of nests monitored between 1991 and 1994 downstream of the Castlegar pulp mill, despite changes in bleaching technology (CIO2 substitution). However, by 1997 concentrations of 2, 3,7,8-TCDD and -TCDF were significantly lower than previous years in nests sampled downstream at both Castlegar and Kamloops. An unusual pattern of higher chlorinated PCDDs and PCDFs was found in many of the osprey eggs collected in this study, and considerable individual variation in the pattern existed among eggs from the same site. For example, eggs from four different nests at one study area (Quesnel) on the Fraser River had concentrations of 1,2,3,4,6,7,8-HpCDD ranging from <1 to 1,100 ng/kg and OCDD from <1 to 7,000 ng/kg wet weight. Higher mean concentrations of HpCDD and OCDD were found in eggs from the Thompson River, a tributary of the Fraser, compared to the Columbia River, and concentrations were generally higher at nests upstream of pulp mills. In plasma samples, 1,2,3,4,6,7,8-HpCDD and OCDD were the main compounds detected, with no significant differences measured between samples upstream versus downstream or earlier versus later in the breeding season. Use of chlorophenolic wood preservatives by lumber processors was considered the main source of higher chlorinated PCDD/Fs throughout the systems, based on patterns of trace PCDFs in eggs and significant correlations between egg concentrations of pentachlorophenol and both HpCDD (r = 0.891, p < 0.01) and OCDD (r = 0.870, p < 0.01).

Human body burden of polychlorinated dibenzofurans associated with toxicity based on the yusho and yucheng incidents

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

Ryan, J.J.; Gasiewicz, T.A.; Brown, J.F. Jr.

1990-11-01

The polychlorinated dibenzofurans (PCDFs) are one group of man-made toxicants for which reasonably extensive data exist relevant to dose-response relationships in humans. Examination of contaminated food oil consumption from the yusho (Japan) poisoning incident indicates the mean uptake or body burden of 2, 3, 4, 7, 8-pentachlorodibenzofuran (PnCDF) equivalents (PEQ) associated with nausea and anorexia to be 4.4 micrograms/kg body wt and that associated with chloracne to be 5.9 micrograms/kg. For the yucheng (Taiwan) poisoning incident, blood measurements for chloracne show a similar body burden of 4.0 micrograms/kg. The latter value is toxicologically equivalent to a 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalent (TEQ) bodymore » burden of 2.0 micrograms/kg body wt or about 150 micrograms for an adult person. This corresponds to an adipose tissue level of about 10 micrograms/kg fat, and is comparable to that known to cause chloracne in rhesus monkeys. These body burdens on a TEQ basis are more than 200 times higher than the average current levels of PCDDs/PCDFs found in North American populations and are the first to relate human body burdens of PCDFs with a known effect and to compare them to animal data. Since the effects reported may not be the most sensitive indicator of human toxicity, lower body burdens could be associated with more subtle toxicological events.« less

Effect of ammonium sulfate and urea on PCDD/F formation from active carbon and possible mechanism of inhibition.

PubMed

Yan, Mi; Qi, Zhifu; Yang, Jie; Li, Xiaodong; Ren, Jianli; Xu, Zhang

2014-11-01

The effect of ammonium sulfate ((NH4)2SO4) and urea (CO(NH2)2) on polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) formation from active carbon was investigated in this study. Both additives could significantly inhibit PCDD/F formation, and PCDD/F (TEQ) generation was reduced to 98.5% (98%) or 64.5% (77.2%) after 5% (NH4)2SO4 or CO(NH2)2 was added into model ash, respectively. The inhibition efficiency of PCDDs was higher than the value of PCDFs, however, the reduction of PCDD/F yield was mainly from PCDFs decreasing. In addition, the solid-phase products were reduced more than the gas-phase compounds by inhibitors. By the measurement of chlorine emission in the phase of ion (Cl[Cl(-)]) and molecule gas (Cl[Cl2]), it was observed that both Cl[Cl(-)] and Cl[Cl2] were reduced after inhibitors were added into ash. Cl[Cl2] was reduced to 51.0% by urea addition, which was supposed as one possible mechanism of PCDD/F inhibition. Copyright © 2014. Published by Elsevier B.V.

Evaluation of gas-particle partition of dioxins in flue gas I: evaluation of gasification behavior of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in fly ash by thermal treatment.

PubMed

Yokohama, Naoki; Otaka, Hiroaki; Minato, Ichiro; Nakata, Munetaka

2008-05-01

The gasification behavior of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in fly ash by thermal treatment has been investigated to estimate gas-particle partition in flue gas. The results obtained in thermal experiments under various conditions showed that gasification of PCDD/Fs depends on air flow rate and treatment weight of fly ash as well as treatment temperature. On the other hand, the results obtained in the thermal experiments using dioxin-free fly ash revealed that during thermal treatment, the de novo synthesis, gasification, and decomposition of PCDFs proceeded at different rates. This difference in the reaction rates indicates that thermal treatment time is also a factor in determining the gas-particle partition of PCDD/Fs in fly ash. Therefore, reasonable thermal treatment conditions were established and applied to three ash samples. For all samples, PCDD/Fs started to gasify at 350 degrees C treatment, whereas 53-98% of PCDD/F homologs gasified at 400 degrees C treatment, implying that gaseous PCDD/Fs are dominant in flue gas at temperatures in the range 350-400 degrees C regardless of particle concentration.

Concentrations of polychlorinated dibenzo-p-dioxins in processed ball clay from the United States.

PubMed

Ferrario, Joseph; Byrne, Christian; Schaum, John

2007-04-01

Processed ball clays commonly used by the ceramic art industry in the United States were collected from retail suppliers and analyzed for the presence and concentration of the 2,3,7,8-Cl substituted polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs). The average PCDD toxic equivalent (TEQ) concentrations of these processed ball clays was approximately 800 pg/g (TEQ-WHO) with characteristic congener profiles and isomer distributions similar to patterns of previously analyzed raw and processed ball clays. The PCDF concentrations were below the average limit of detection (LOD) of 0.5 pg/g. Correlation analyses reveal no significant relationship between total organic carbon (TOC) and either individual, homologues, and total tetra-through octa-chlorinated PCDD congeners, or TEQ concentrations of the processed ball clays. The results are consistent with earlier studies on levels of PCDDs in ball clays. Data from earlier studies indicated that dioxins may be released to the environment during the processing of raw clay or the firing process used in commercial ceramic facilities. The presence of dioxin in the clays also raises concerns about potential occupational exposure for individuals involved in the mining/processing of ball clay, ceramics manufacturing and ceramic artwork.

Determination of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in Brazilian cow milk.

PubMed

Rocha, Dayse A M; Torres, João P M; Reichel, Klaus; Novotny, Etelvino H; Estrella, Leonardo F; Medeiros, Rebeca O; Netto, Annibal D Pereira

2016-12-01

The determination of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in raw cow milks have never been reported in Brazil. Since the consumption of food of animal origin, including milk and dairy products, is the major source of human exposure to these compounds, this study aimed to establish the levels and profile of seven PCDDs and ten PCDFs in raw cow milk samples collected in eight Brazilian states which among the major milk producer states. Raw milk samples were collected in 34 different dairy cattle farms during the summer of 2013. All PCDD/Fs congeners were found at least in some of the 34 samples studied. The octa-chlorinated congeners (OCDD and OCDF) were ubiquitous and also present in high concentrations. The mean values of WHO-TEQ 1998;2005 were respectively 1.66 and 1.36pgTEQg -1 fat and samples taken in São Paulo showed the highest WHO-TEQ values (2.46 TEQ 1998 g -1 fat and 2.10pgTEQ 2005 g -1 fat). Although all samples showed some contamination level, all values were below the limit established by European Union for total PCDD/Fs in cow milk (3pgWHO-TEQ 1998 g -1 fat). Principal Component Analysis (PCA) showed that OCDD and OCDF were responsible for 73% and 20% of the total data variance, respectively and they presented an independent behavior, probably as a result of distinct origins. The use of TEQ as weights in the PCA, revealed the importance of the penta-chloro congeners and it was possible to identify sample distribution patterns probably associated with the main PeCDD and PeCDF. The importance of local sources to PCDD/Fs concentrations is still to be evaluated and determined. Copyright © 2016 Elsevier B.V. All rights reserved.

Evaluation of the toxicity of sediments from the Anniston PCB Site to the mussel Lampsilis siliquoidea

USGS Publications Warehouse

Schein, Allison; Sinclair, Jesse A.; MacDonald, Donald D.; Ingersoll, Christopher G.; Kemble, Nile E.; Kunz, James L.

2015-01-01

The Anniston Polychlorinated Biphenyl (PCB) Site is located in the vicinity of the municipality of Anniston in Calhoun County, in the north-eastern portion of Alabama. Although there are a variety of land-use activities within the Choccolocco Creek watershed, environmental concerns in the area have focused mainly on releases of PCBs to aquatic and riparian habitats. PCBs were manufactured by Monsanto, Inc. at the Anniston facility from 1935 to 1971. The chemicals of potential concern (COPCs) in sediments at the Anniston PCB Site include: PCBs, mercury, metals, polycyclic aromatic hydrocarbons (PAHs), organochlorine and organophosphorous pesticides, volatile organic compounds (VOCs), semivolatile organic compounds (SVOCs), and polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/PCDFs). The purpose of this study was to evaluate the toxicity of PCB-contaminated sediments to the juvenile fatmucket mussel (Lampsilis siliquoidea) and to characterize relationships between sediment chemistry and the toxicity of sediment samples collected from the Anniston PCB Site using laboratory sediment testing. Samples were collected in August 2010 from OU-4 of the Anniston PCB Site, as well as from selected reference locations. A total of 32 samples were initially collected from six test sites and one reference site within the watershed. A total of 23 of these 32 samples were evaluated in 28-day whole-sediment toxicity tests conducted with juvenile mussels (L. siliquoidea). Physical and chemical characterization of whole sediment included grain size, total organic carbon (TOC), nutrients, PCBs, parent and alkylated PAHs, organochlorine pesticides, PCDD/PCDFs, total metals, simultaneously extracted metals (SEM), and acid volatile sulfide (AVS). Sediment collected from Snow Creek and Choccolocco Creek contained a variety of COPCs. Organic contaminants detected in sediment included PCBs, organochlorine pesticides, PCDDs/PCDFs, and PAHs. In general, the highest concentrations of PCBs were associated with the highest concentrations of PAHs, PCDDs/PCDFs, and organochlorine pesticides. Specifically, sediments 08, 18, and 19 exceeded probable effect concentration quotients (PEC-Qs) of 1.0 for all organic classes of contaminants. These three sediment samples also had high concentrations of mercury and lead, which were the only metals found at elevated concentrations (i.e., above the probable effect concentration [PEC]) in the samples collected. Many sediment samples were highly contaminated with mercury, based on comparisons to samples collected from reference locations. The whole-sediment laboratory toxicity tests conducted with L. siliquoidea met the test acceptability criteria (e.g., control survival was greater than or equal to 80%). Survival of mussels was high in most samples, with 4 of 23 samples (17%) classified as toxic based on the survival endpoint. Biomass and weight were more sensitive endpoints for the L. siliquoidea toxicity tests, with both endpoints classifying 52% of the samples as toxic. Samples 19 and 30 were most toxic to L. siliquoidea, as they were classified as toxic according to all four endpoints (survival, biomass, weight, and length). Mussels were less sensitive in toxicity tests conducted with sediments from the Anniston PCB Site than Hyalella azteca and Chironomus dilutus. Biomass of L. siliquoidea was less sensitive compared to biomass of H. azteca or biomass of larval C. dilutus. Based on the most sensitive endpoint for each species, 52% of the samples were toxic to L. siliquoidea, whereas 67% of sediments were toxic to H. azteca (based on reproduction) and 65% were toxic to C. dilutus (based on adult biomass). The low-risk toxicity threshold (TTLR) was higher for L. siliquoidea biomass (e.g., 20,400 µg/kg dry weight [DW]) compared to that for H. azteca reproduction (e.g., 499 µg/kg DW) or C. dilutus adult biomass (e.g., 1,140 µg/kg DW; MacDonald et al. 2014). While mussels such as L. sili

Chlorine-Free Red-Burning Pyrotechnics.

PubMed

Sabatini, Jesse J; Koch, Ernst-Christian; Poret, Jay C; Moretti, Jared D; Harbol, Seth M

2015-09-07

The development of a red, chlorine-free pyrotechnic illuminant of high luminosity and spectral purity was investigated. Red-light emission based solely on transient SrOH(g) has been achieved by using either 5-amino-1H-tetrazole or hexamine to deoxidize the combustion flame of a Mg/Sr(NO3 )2 /Epon-binder composition and reduce the amount of both condensed and gaseous SrO, which emits undesirable orange-red light. The new formulations were found to possess high thermal onset temperatures. Avoiding chlorine in these formulations eliminates the risk of the formation of PCBs, PCDDs, and PCDFs. This finding, hence, will have a great impact on both military pyrotechnics and commercial firework sectors. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Review of organohalogen toxicants in fish from the Gulf of Finland

NASA Astrophysics Data System (ADS)

Vuorinen, Pekka J.; Roots, Ott; Keinänen, Marja

2017-07-01

A literature survey identified 30 articles providing data on the concentrations of organohalogen compounds in fish caught from the Gulf of Finland: polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs), the chlorinated pesticide DDT and polybrominated diphenylethers (PBDEs). Results were found for 14 fish species in total, but mainly for herring (Clupea harengus), salmon (Salmo salar) and sprat (Sprattus sprattus), and the oldest data were for PCBs, from 1975. PCBs and PCDDs were the most prevalent organohalogens in the Gulf of Finland compared to other areas of the Baltic Sea. In particular, more local fish species and benthic feeders caught from the eastern parts of the Gulf of Finland appear to contain higher concentrations of organochlorines than those from the western parts. The concentration of dioxins plus dioxin-like PCBs as WHO-TEQPCDD/F + PCB in herring has demonstrated a decreasing trend since the late 1970s. However, the maximum allowable concentration of WHO-TEQPCDD/F + PCB in fish set by the EC was exceeded in all salmon and older herring specimens and in some whitefish (Coregonus lavaretus), bream (Abramis brama), sea trout (Salmo trutta) and flounder (Platichthys flesus). The respective limit concentration for fish used as animal feed was exceeded in most of the fish samples.

Evaluation of the release of dioxins and PCBs during kiln-firing of ball clay.

PubMed

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.

Levels of non-ortho-substituted (coplanar), mono- and di-ortho-substituted polychlorinated biphenyls, dibenzo-p-dioxins, and dibenzofurans in human serum and adipose tissue.

PubMed Central

Patterson, D G; Todd, G D; Turner, W E; Maggio, V; Alexander, L R; Needham, L L

1994-01-01

We have measured non-ortho-substituted (coplanar) polychlorinated biphenyl (PCB) levels as well as polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) levels in human adipose tissue and serum collected in Atlanta, Georgia. The results show that the concentrations of the coplanar PCBs can be more than an order of magnitude higher than the concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin. Our measurements in pooled serum collected in 1982, 1988, and 1989 show a decrease in coplanar PCB levels from 1982 to 1989. We found that the pattern of relative amounts of coplanar PCBs in adipose tissue varied greatly from person to person unlike the PCDD and PCDF patterns, which were more nearly the same. Age was significantly correlated with the concentrations of 2,3,7,8-TCDD,3,3'4,4'-PCB, 3,3',4,4',5-PCB, and 3,3'4,4',5,5'-PCB in adipose tissue. We also measured levels of the mono- and di-ortho chlorine-substituted PCBs in human serum. The levels for some of these PCB congeners were three orders of magnitude higher than the coplanar PCBs, PCDDs, and PCDFs. We used the international toxicity equivalency factors (TEFs) for PCDDs and PCDFs and the TEFs proposed by Safe for PCBs to calculate the 2,3,7,8-TCDD equivalents. Four PCBs (3,3',4,4',5-; 2,3',4,4',5-;2,3,3',4,4'-;2,3,3',4,4',5-) make a larger contribution than 2,3,7,8-TCDD, while four other PCBs (3,3',4,4'5,5'-; 2,2',3,4,4',5'-;2,2',4,4',5,5'-;2,2',3,4,4',5,5'-) make nearly the same contribution as 2,3,7,8-TCDD. The mono-ortho-chlorine-substituted 2,3',4,4',5-PCB, however, is the major contributor to the total 2,3,7,8-TCDD equivalents in general population samples from the United States, Sweden, and Japan.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8187709

[Measurement of chemical agents in metallurgy field: electric steel plant].

PubMed

Cottica, D; Grignani, E; Ghitti, R; Festa, D; Apostoli, P

2012-01-01

The steel industry maintains its important position in the context of the Italian production involving thousands of workers. The iron and steel processes are divided into primary steel industry, production of intermediate minerals, and secondary steel, scrap from the production of semi-finished industrial and consumer sector (metal inserted into components and metal used for dissipative uses, primarily coatings) and industrial waste. The paper presents the results of environmental monitoring carried out in some electric steel plant for the measurement of airborne chemicals that characterize the occupational exposure of workers employed in particular area like electric oven, to treatment outside the furnace, continuous casting area. For the sampling of the pollutants were used both personal and in fixed positions samplers. The pollutants measured are those typical of steel processes inhalable dust, metals, respirable dust, crystalline silica, but also Polycyclic Aromatic Hydrocarbons (PAH), polychlorinated dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs).

Persistent organic pollutants in human breast milk from Asian countries.

PubMed

Tanabe, Shinsuke; Kunisue, Tatsuya

2007-03-01

In this paper, we concisely reviewed the contamination of persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), hexachlorobenzene (HCB) in human breast milk collected from Asian countries such as Japan, China, Philippines, Vietnam, Cambodia, India, Malaysia, and Indonesia during 1999-2003. Dioxins, PCBs, CHLs in Japanese, and DDTs in Vietnamese, Chinese, Cambodian, Malaysian, and HCHs in Chinese, Indian, and HCB in Chinese breast milk were predominant. In India, levels of dioxins and related compounds (DRCs) in the mothers living around the open dumping site were notably higher than those from the reference site and other Asian developing countries, indicating that significant pollution sources of DRCs are present in the dumping site of India and the residents there have been exposed to relatively higher levels of these contaminants possibly via bovine milk.

PCDDs, PCDFs and PCBs in farmed fish produced in Greece: Levels and human population exposure assessment.

PubMed

Costopoulou, Danae; Vassiliadou, Irene; Leondiadis, Leondios

2016-03-01

Fish is among the essential components of Mediterranean diet and has beneficial effects on human health. Farmed fish is an affordable alternative to wild fish and a significant food export product for Greece. Published studies worldwide have reported significant levels of environmental pollutants in fish tissues. Especially for PCDDs/Fs and PCBs, the studies suggest that the most important contribution to human dietary intake is from fish and seafood. In the present study, we investigate the levels of PCDDs/Fs, dioxin-like and non dioxin-like PCBs in the most common farmed fish species produced in Greece i.e. sea bass, sea bream and rainbow trout. These species are widely consumed in Greece and are also exported to many countries worldwide. The mean levels found were WHO-PCDD/F-TEQ: 0.22 pg g(-1) wet weight (w.w.), WHO-PCDD/F-PCB-TEQ: 0.88 pg g(-1) w.w. for sea bream, WHO-PCDD/F-TEQ: 0.13 pg g(-1) w.w., WHO-PCDD/F-PCB-TEQ: 0.68 pg g(-1) w.w. for sea bass and WHO-PCDD/F-TEQ: 0.10 pg g(-1) w.w., WHO-PCDD/F-PCB-TEQ: 0.43 pg g(-1) w.w. for rainbow trout. For non dioxin-like PCBs, mean sum values found were 8.02 ng g(-1) w.w. for sea bream, 5.24 ng g(-1) w.w. for sea bass and 2.90 ng g(-1) w.w. for rainbow trout. All concentrations found were far below maximum levels set by the European Union and in the same range as wild-caught fish also presented for comparison. Daily intake from the consumption of farmed fish species examined is calculated at 1.3 pg WHO-TEQ kg(-1) b.w., which is at the lowest end of TDI values proposed by the WHO. Copyright © 2015 Elsevier Ltd. All rights reserved.

Human exposure to PCDDs and their precursors from heron and tern eggs in the Yangtze River Delta indicate PCP origin.

PubMed

Zhou, Yihui; Yin, Ge; Asplund, Lillemor; Stewart, Kathryn; Rantakokko, Panu; Bignert, Anders; Ruokojärvi, Päivi; Kiviranta, Hannu; Qiu, Yanling; Ma, Zhijun; Bergman, Åke

2017-06-01

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are highly toxic to humans and wildlife. In the present study, PCDD/Fs were analyzed in the eggs of whiskered terns (Chlidonias hybrida), and genetically identified eggs from black-crowned night herons (Nycticorax nycticorax) sampled from two lakes in the Yangtze River Delta area, China. The median toxic equivalent (TEQ) of PCDD/Fs were 280 (range: 95-1500) and 400 (range: 220-1100) pg TEQ g -1 lw (WHO, 1998 for birds) in the eggs of black-crowned night heron and whiskered tern, respectively. Compared to known sources, concentrations of PCDDs relative to the sum of PCDD/Fs in bird eggs, demonstrated high abundance of octachlorodibenzo-p-dioxin (OCDD), 1,2,3,4,6,7,8-heptaCDD and 1,2,3,6,7,8-hexaCDD indicating pentachlorophenol (PCP), and/or sodium pentachlorophenolate (Na-PCP) as significant sources of the PCDD/Fs. The presence of polychlorinated diphenyl ethers (PCDEs), hydroxylated and methoxylated polychlorinated diphenyl ethers (OH- and MeO-PCDEs, known impurities in PCP products), corroborates this hypothesis. Further, significant correlations were found between the predominant congener CDE-206, 3'-OH-CDE-207, 2'-MeO-CDE-206 and OCDD, indicating a common origin. Eggs from the two lakes are sometimes used for human consumption. The WHO health-based tolerable intake of PCDD/Fs is exceeded if eggs from the two lakes are consumed regularly on a weekly basis, particularly for children. The TEQs extensively exceed maximum levels for PCDD/Fs in hen eggs and egg products according to EU legislation (2.5 pg TEQ g -1 lw). The results suggest immediate action should be taken to manage the contamination, and further studies evaluating the impacts of egg consumption from wild birds in China. Likewise, studies on dioxins and other POPs in common eggs need to be initiated around China. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Lipid reserve dynamics and magnification of persistent organic pollutants in spawning sockeye salmon (Oncorhynchus nerka) from the Fraser River, British Columbia.

PubMed

Kelly, Barry C; Gray, Samantha L; Ikonomou, Michael G; Macdonald, J Steve; Bandiera, Stelvio M; Hrycay, Eugene G

2007-05-01

Pacific sockeye salmon (Oncorhynchus nerka) can travel several hundred kilometers to reach native spawning grounds and fulfill semelparous reproduction. The dramatic changes in lipid reserves during upstream migration can greatly affect internal toxicokinetics of persistent organic pollutants (POPs) such as PCBs, PCDDs, and PCDFs. We measured lipid content changes and contaminant concentrations in tissues (liver, muscle, roe/gonads) and biomarker responses (ethoxyresorufin O-deethylase or EROD activity and CYP1A levels) in two Pacific sockeye salmon stocks sampled at several locations along their spawning migration in the Fraser River, British Columbia. Muscle lipid contents declined significantly with increasing upstream migration distance and corresponded to elevated lipid normalized concentrations of PCBs and PCDD/Fs in spawning sockeye. Post-migration magnification factors (MFs) in spawning sockeye ranged between 3 and 12 and were comparable to model-predicted MFs. sigmaPCBs(150-500 ng x g(-1) lipid), sigmaPCDD/Fs (1-1000 pg x g(-1) lipid) and 2,3,7,8-TCDD toxic equivalent or TEQ levels (0.1-15 pg x g(-1) lipid) in spawning sockeye were relatively low and did not affect hepatic EROD activity/CYP1A induction. Despite a 3-fold magnification, TEQ levels in eggs of spawning Fraser River sockeye did not exceed 0.3 pg x g(-1) wet wt, a threshold level associated with 30% egg mortality in salmonids. PCBs in Fraser River sockeye are comparable to previous levels in Pacific sockeye. In contrast to Pacific sockeye from more remote coastal locations, PCDDs and PCDFs in Fraser River sockeye were generally minor components (<25%) of TEQ levels, compared to dioxin like PCB contributions (>75%). The data suggest that (i) the Fraser River is not a major contamination source of PCBs or PCDD/Fs and (ii) marine contaminant distribution, food-chain dynamics, and ocean-migration pathway are likely important factors controlling levels and patterns of POPs in returning Pacific sockeye. We estimate an annual chemical flux entering the Fraser River of up to 150 g for sigmaPCBs and 40 mg for sigmaPCDD/ Fs via returning sockeye. The results indicate that historical concentrations of PCBs and PCDD/Fs remain a potential threat to organism and ecosystem health on the west coast of Canada.

PCBs and PCDD/Fs in soil from informal e-waste recycling sites and open dumpsites in India: Levels, congener profiles and health risk assessment.

PubMed

Chakraborty, Paromita; Selvaraj, Sakthivel; Nakamura, Masafumi; Prithiviraj, Balasubramanian; Cincinelli, Alessandra; Bang, John J

2018-04-15

Growth of informal electronic waste (e-waste) recycling sector is an emerging problem for India. The presence of halogenated compounds in e-wastes may result in the formation of persistent organic pollutants like polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during recycling processes. We therefore investigated PCBs and PCDD/Fs in surface soils explicitly from the informal e-waste recycling sites and nearby open dumpsites of major metropolitan cities from four corners of India, viz., New Delhi (North), Kolkata (East), Mumbai (West) and Chennai (South). In the informal e-waste recycling sites, the range of Σ 26 PCBs (0.4-488ng/g) and ƩPCDD/Fs (1.0-10.6ng/g) were higher than Ʃ 26 PCBs (0.3-21ng/g) and ƩPCDD/Fs (0.15-7.3ng/g) from open dumpsites. In the e-waste sites, ƩPCDDs were found with increasing trend from ƩTetraCDD to OctaCDD, whereas ƩPCDFs showed a reverse trend. The dominance of PCDF congeners and maximum toxicity equivalents (TEQ) for both PCDDs (17pg TEQ/g) and PCDFs (82pg TEQ/g) at Mandoli in New Delhi has been related to intensive precious metal recovery process using acid bath. Among dumpsites, highest TEQ for PCDD/Fs was observed at Kodangaiyur dumpsite of Chennai (CN DS -02, 45pg TEQ/g). Positive Matrix Factorization (PMF) model identified distinct congener pattern based on the functional activities, such as e-waste dismantling, shredding, precious metal recovery and open burning in dumpsites. E-waste metal recovery factor was loaded with 86-91% of PCB-77, -105, -114, -118 and 30% of PCB-126, possibly associated with the burning of wires during the copper extraction process. Almost 70% of the Ʃ 26 PCB concentrations was comprised of the dioxin-like PCB congeners with a maximum concentration of 437ng/g at New Moore market in Chennai, followed by Wire Lane (102ng/g), in Mumbai. We speculate that PCB-126 might have resulted from combustion of plastic materials in e-waste stream and dumped waste. Copyright © 2017 Elsevier B.V. All rights reserved.

Blood levels of dioxins, furans, dioxin-like PCBs, and TEQs in general populations: a review, 1989-2010.

PubMed

Consonni, Dario; Sindaco, Raffaella; Bertazzi, Pier Alberto

2012-09-01

A comprehensive worldwide literature review of blood levels of dioxins and dioxin-like compounds in non-exposed adult general populations was performed. The studies published in 1989-2010 reporting information on polychlorinated dibenzo-para-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), non-ortho-PCBs (nPCBs), mono-ortho-PCBs (mPCBs) levels and Toxic Equivalencies (TEQs, a summary weighted measure of their combined toxicity) were reviewed. TEQs were calculated using as standard the most recent WHO 2005 reevaluation of Toxic Equivalency Factors (TEFs). Weighted multiple regression analyses adjusted for year, subject's age, type of sample analyzed, method used for values below detection limit, and central tendency measure used were performed for each congener and standardized TEQs (log-transformed). We identified 187 studies regarding 29,687 subjects of 26 countries. Year of blood collection ranged from 1985 to 2008. The studies reporting congener levels 161. In adjusted analyses, European countries showed higher levels of most dioxin-like congeners and TEQs. A strong positive association of subjects' age with most congeners and with TEQ values was found, confirming previous findings. Significant decreases over time (1985-2008) were documented for PCCDs, PCDFs, and TEQs including their contributions. No significant decrease was found for non-ortho-PCBs, notably PCB 126. Only some mono-ortho-PCBs showed clear significant declines. Accordingly, TEQs including only PCB contribution did not decrease over time. In interpreting these findings, it should be considered that for dioxin-like PCBs the analysis period was shorter (17 years), since these compounds were first measured in 1992. Copyright © 2012 Elsevier Ltd. All rights reserved.

Polybrominated diphenyl ethers, polychlorinated dibenzo-dioxins, -furans, and -biphenyls in three species of Antarctic penguins.

PubMed

Corsolini, Simonetta; Borghesi, Nicoletta; Schiamone, Alessandra; Focardi, Silvano

2007-09-01

Fish-eating seabirds are recognized to be at risk of accumulating toxic contaminants due to their high position in the trophic web and to their low ability to metabolize xenobiotic compounds. Penguins are widely distributed in Antarctica and represent an important fraction of the Antarctic biomass. They feed mainly on krill and, depending on krill availability, also on fish. It has been reported that predators may be a sink for volatile and toxic chemicals and this may pose a serious environmental problem. Polybrominated diphenyl ethers (PBDEs), polychlorinated dibenzo-dioxins (PCDDs), -furans (PCDFs), and -biphenyls (PCBs), including non-ortho congeners, hexachlorobenzene (HCB) and p,p'-DDE, were quantified in three species of Antarctic Pygoscelids in order to evaluate their accumulation patterns. The potential toxicity of twenty-two dioxin-like congeners was assessed and expressed as 2,3,7,8-tetraCDD equivalents (TEQs). Differences between males and females were investigated. Blood samples of the Adélie penguin Pygoscelis adeliae, Chinstrap penguin Pygoscelis antarctica and Gentoo penguin Pygoscelis papua were collected at Admiralty Bay, King George Is (62 degrees 10'39" S, 58 degrees 26'46" W) in February 2004. Halogenated hydrocarbons were identified and quantified using gas chromatography coupled with gas chromatography mass spectrometry analyses. Results are expressed on a wet weight basis. HCB, p,p'-DDE and sigmaPCBs were higher in Adélie penguins (6.7 +/- 6.1, 8.2 +/- 3.3 and 9.8 +/- 3.8 ng/g, respectively) than in Chinstrap and Gentoo penguins, both of which showed values in the same order of magnitude, but approximately 40% lower than Adélie penguins. Hexa-CBs ranged 35-45% of the residue. Low-chlorinated PCBs (nos. 70+76+95+ 56+60+101) accounted for 40-60% in the three species. PCB101 made up 15% of the residue in Adélie penguins. PBDEs were 291 +/- 477, 107 +/- 104 and 116 +/- 108 pg/g in Adélie, Chinstrap and Gentoo penguins, respectively; the most abundant congeners were BDE47 in Adélie and Chinstrap penguins and BDE17 in Gentoo penguins. PCDDs were 22 +/- 32, 6.5 +/- 7.4 and 18 +/- 23 pg/g in Adélie, Chinstrap and Gentoo penguins, respectively. PCDFs were higher in Adélie penguins and lower in Chinstrap penguins. PCDDs/Fs and PBDEs were higher in males than in females of Gentoo and Chinstrap penguins; differences in concentrations were likely related to the partial detoxification that occurs in females during egg formation. Of the four non-ortho PCBs measured, PCB126 occurred at the highest concentrations and contributed the majority of the non-ortho PCB-TEQ in Gentoo and Chinstrap penguins. The highest TEQs were found in the Gentoo penguin and due mainly to PCDDs and non-ortho PCBs. POP concentrations in penguins were lower than those found in seabird species from other areas of the world. Different chemical accumulation patterns were observed in relation to species and sex; the Adélie penguin showed the highest POP levels. Dissimilar ecological or metabolic features may be involved; the diverse timing of reproduction steps can be responsible for those differences; moreover, Adélie penguins feed on krill (a fatty resource) more abundantly than the other two species during the rearing period. The South Shetland Islands might be subjected to a higher chemical impact with respect to the rest of Antarctica, due to their being near South America. Because penguins are fish-eating birds showing low detoxifying capacities and key-species in Antarctic ecosystems, further studies on their xenobiotic metabolism should be carried out.

Polycyclic aromatic hydrocarbons in oysters and sediments from the Yatsushiro Sea, Japan: comparison of potential risks among PAHs, dioxins and dioxin-like compounds in benthic organisms.

PubMed

Nakata, Haruhiko; Uehara, Kiriko; Goto, Yuta; Fukumura, Miki; Shimasaki, Hideyuki; Takikawa, Kiyoshi; Miyawaki, Takashi

2014-01-01

Polycyclic aromatic hydrocarbons (PAHs) were analyzed in oysters collected from 18 stations in the Yatsushiro Sea, western Japan. PAHs were detected in all samples analyzed, and the highest concentration (mean 230 ng/g wet weight) was found in oysters from Tanoura Bay. The high molecular weight PAHs to low molecular weight PAHs ratios in oysters from Tanoura Bay were higher than at other stations. Sediment samples collected from 42 stations in Tanoura Bay were analyzed for PAHs to understand their concentrations and distribution. Higher concentrations were found in sediment samples at two stations in the southern inner bay (mean 30,200 ng/g dry weight), which were approximately two orders of magnitude higher than at a reference site. These observations strongly suggest severe contamination and significant sources of PAHs in Tanoura Bay. Dioxins and dioxin-like compounds (PCDFs, and non- and mono-ortho coplanar PCBs) were analyzed in sediments from eight stations in Tanoura Bay. The concentrations were comparable to, or lower than, at the reference sites, suggesting that there are no specific sources of these compounds in this bay. PAH, dioxins and dioxin-like compounds DR-CALUX relative potencies (REP) were applied to the sediment concentrations to evaluate the potential for toxicological effects on benthic organisms. PAHs made the highest contribution to the total REP concentration, supplying 99% of the total REP, followed by PCDDs (0.18%), PCDFs (0.04%), and PCBs (<0.001%). In this area, PAHs appear to be the most important Ah receptor binding chemicals for potential toxicity to benthic species. © 2013 Published by Elsevier Inc.

Dioxins/furans and PCBs in Canadian human milk: 2008-2011.

PubMed

Rawn, Dorothea F K; Sadler, Amy R; Casey, Valerie A; Breton, François; Sun, Wing-Fung; Arbuckle, Tye E; Fraser, William D

2017-10-01

Human milk was collected between 2008 and 2011 as part of the Maternal - Infant Research on Environmental Chemicals (MIREC) study that was initiated to establish Canadian national estimates of maternal and infant exposure to a broad suite of environmental contaminants (e.g., persistent organic pollutants [POPs], trace elements, phthalates, etc.). Among the 1017 human milk samples collected, 298 were analysed for polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs). World Health Organization (WHO) toxic equivalency concentrations (WHO TEQ 2005 ) for PCDD/F+dioxin-like (DL) PCB ranged from 2.2pg TEQ 2005 g -1 lipid to 27pg TEQ 2005 g -1 lipid. The relative contribution of PCDDs to the overall WHO TEQ 2005 (PCDD/F+DL PCB) has decreased from earlier investigations into POP levels in Canadian human milk. Significantly higher PCB concentrations were observed in milk from women born in Europe relative to those born in Canada (p<0.001), in contrast to results for the PCDD/Fs (p=0.496). Age was found to significantly impact milk ∑PCB concentrations (p=0.018), with elevated concentrations observed in milk from women >30years relative to those <30years of age. While this trend was also observed for the PCDD/Fs, this relationship was impacted by parity. WHO TEQ 2005 concentrations were significantly higher in milk from primiparous women (p=0.019) and those >30years relative to those <30years of age (p<0.001). No significant differences were associated with education level or pre-pregnancy body mass index. PCB and PCDD/F concentrations have continued to decline in Canadian human milk since the last sampling of human milk was performed. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Oceanic biogeochemical controls on global dynamics of persistent organic pollutants.

PubMed

Dachs, Jordi; Lohmann, Rainer; Ockenden, Wendy A; Méjanelle, Laurence; Eisenreich, Steven J; Jones, Kevin C

2002-10-15

Understanding and quantifying the global dynamics and sinks of persistent organic pollutants (POPs) is important to assess their environmental impact and fate. Air-surface exchange processes, where temperature plays a central role in controlling volatilization and deposition, are of key importance in controlling global POP dynamics. The present study is an assessment of the role of oceanic biogeochemical processes, notably phytoplankton uptake and vertical fluxes of particles, on the global dynamics of POPs. Field measurements of atmospheric polychlorinated biphenyls (PCBs), polychlorinated dibenzodioxins (PCDDs), and furans (PCDFs) are combined with remote sensing estimations of oceanic temperature, wind speed, and chlorophyll, to model the interactions between air-water exchange, phytoplankton uptake, and export of organic matter and POPs out of the mixed surface ocean layer. Deposition is enhanced in the mid-high latitudes and is driven by sinking marine particulate matter, rather than by a cold condensation effect. However, the relative contribution of the biological pump is a function of the physical-chemical properties of POPs. It is concluded that oceanic biogeochemical processes play a critical role in controlling the global dynamics and the ultimate sink of POPs.

Characterization of the particulate emissions from the BP Deepwater Horizon surface oil burns.

PubMed

Gullett, Brian K; Hays, Michael D; Tabor, Dennis; Wal, Randy Vander

2016-06-15

Sampling of the smoke plumes from the BP Deepwater Horizon surface oil burns led to the unintentional collection of soot particles on the sail of an instrument-bearing, tethered aerostat. This first-ever plume sampling from oil burned at an actual spill provided an opportunistic sample from which to characterize the particles' chemical properties for polycyclic aromatic hydrocarbons (PAHs), organic carbon, elemental carbon, metals, and polychlorinated dibenzodioxins/dibenzofurans (PCDDs/PCDFs) and physical properties for size and nanostructure. Thermal-optical analyses indicated that the particulate matter was 93% carbon with 82% being refractory elemental carbon. PAHs accounted for roughly 68μg/g of the PM filter mass and 5mg/kg oil burned, much lower than earlier laboratory based studies. Microscopy indicated that the soot is distinct from more common soot by its aggregate size, primary particle size, and nanostructure. PM-bound metals were largely unremarkable but PCDD/PCDF formation was observed, contrary to other's findings. Levels of lighter PCDD/PCDF and PAH compounds were reduced compared to historical samples, possibly due to volatilization or photo-oxidation. Published by Elsevier Ltd.

Emissions from open burning of simulated military waste from forward operating bases.

PubMed

Aurell, Johanna; Gullett, Brian K; Yamamoto, Dirk

2012-10-16

Emissions from open burning of simulated military waste from forward operating bases (FOBs) were extensively characterized as an initial step in assessing potential inhalation exposure of FOB personnel and future disposal alternatives. Emissions from two different burning scenarios, so-called "burn piles/pits" and an air curtain burner/"burn box", were compared using simulated FOB waste from municipal and commercial sources. A comprehensive array of emissions was quantified, including CO(2), PM(2.5), volatile organic compounds (VOCs), polyaromatic hydrocarbons (PAHs), polychlorinated dibenzodioxins and -furans (PCDDs/PCDFs), polybrominated dibenzodioxins and -furans (PBDDs/PBDFs), and metals. In general, smoldering conditions in the burn box and the burn pile led to similar emissions. However, when the burn box underwent periodic waste charging to maintain sustained combustion, PM(2.5), VOCs, and PAH emissions dropped considerably compared to smoldering conditions and the overall burn pile results. The PCDD/PCDF and PBDD/PBDF emission factors for the burn piles were 50 times higher than those from the burn box likely due to the dominance of smoldering combustion in the burn piles.

Detoxifying PCDD/Fs and heavy metals in fly ash from medical waste incinerators with a DC double are plasma torch.

PubMed

Pan, Xinchao; Yan, Jianhua; Xie, Zhengmiao

2013-07-01

Medical waste incinerator (MWI) fly ash is regarded as a highly toxic waste because it contains high concentrations of heavy metals and dioxins, including polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Therefore fly ash from MWI must be appropriately treated before being discharged into the environment. A melting process based on a direct current thermal plasma torch has been developed to convert MWI fly ash into harmless slag. The leaching characteristics of heavy metals in fly ash and vitrified slag were investigated using the toxicity characteristic leaching procedure, while the content of PCDD/Fs in the fly ashes and slags was measured using method 1613 of the US EPA. The experimental results show that the decomposition rate of PCDD/Fs is over 99% in toxic equivalent quantity value and the leaching of heavy metals in the slag significantly decreases after the plasma melting process. The produced slag has a compact and homogeneous microstructure with density of up to 2.8 g/cm3.

Persistent organic pollutants (POPs) in killer whales (Orcinus orca) from the Crozet Archipelago, southern Indian Ocean.

PubMed

Noël, Marie; Barrett-Lennard, Lance; Guinet, Christophe; Dangerfield, Neil; Ross, Peter S

2009-10-01

Persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs), are ubiquitous environmental contaminants of which significant concentrations are reported in upper trophic level animals. In 1998, we collected blubber biopsy samples (n=11) from killer whales (Orcinus orca) inhabiting the coastal waters around Possession Island, Crozet Archipelago, southern Indian Ocean, for contaminant analyses. Despite inhabiting an isolated region far removed from industrial activities, these killer whales can presently be considered among the most PCB-contaminated cetaceans in the southern hemisphere, with concentrations ranging from 4.4 to 20.5mg/kg lipid weight (lw). PCDD levels ranged from below the detection limit (5 ng/kg) to 77.1 ng/kg lw and PCDF levels from below the detection limit (7 ng/kg) to 36.1 ng/kg lw. Over 70% of our study animals had PCB concentrations which exceeded a 1.3mg/kg PCB threshold established for endocrine disruption and immunotoxicity in free-ranging harbour seals, suggesting that organic contaminants cannot be ruled out as an additional threat to this declining population.

Cleaner co-combustion of lignite-biomass-waste blends by utilising inhibiting compounds of toxic emissions.

PubMed

Skodras, G; Palladas, A; Kaldis, S P; Sakellaropoulos, G P

2007-04-01

In this paper, the co-combustion behaviour of coal with wastes and biomass and the related toxic gaseous emissions were investigated. The objective of this work is to add on towards a cleaner co-combustion of lignite-waste-biomass blends by utilizing compounds that could inhibit the formation of toxic pollutants. A series of co-combustion tests was performed in a pilot scale incinerator, and the emissions of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were measured. The co-combustion behaviour of lignite with olive kernels, MDF and sawdust was studied and the ability of additives such as urea, almond shells and municipal sewage sludge to reduce the PCDD/F emissions was examined. All blends were proven good fuels and reproducible combustion conditions were achieved. The addition of inhibitors prior to combustion showed in some cases, relatively high PCDD/F emissions reduction. Among the inhibitors tested, urea seems to achieve a reduction of PCDD/F emissions for all fuel blends, while an unstable behaviour was observed for the others.

Spatial patterns of chemical contamination (metals, PAHs, PCBs, PCDDs/PCDFS) in sediments of a non-industrialized but densely populated coral atoll/small island state (Bermuda).

PubMed

Jones, Ross J

2011-06-01

There is a recognized dearth of standard environmental quality data in the wider Caribbean area, especially on coral atolls/small island states. Extensive surveys of sediment contamination (n=109 samples) in Bermuda revealed a wide spectrum of environmental quality. Zinc and especially copper levels were elevated at some locations, associated with boating (antifouling paints and boatyard discharges). Mercury contamination was surprisingly prevalent, with total levels as high as 12mg kg(-1)DW, although methyl mercury levels were quite low. PAH, PCB and PCDD/PCDF contamination was detected a several hotspots associated with road run-off, a marine landfill, and a former US Naval annexe. NOAA sediment quality guidelines were exceeded at several locations, indicating biological effects are possible, or at some locations probable. Overall, and despite lack of industrialization, anthropogenic chemicals in sediments of the atoll presented a risk to benthic biodiversity at a number of hotspots suggesting a need for sediment management strategies. Copyright © 2011 Elsevier Ltd. All rights reserved.

Modeling the transport of PCDD/F compounds in a contaminated river and the possible influence of restoration dredging on calculated fluxes.

PubMed

Malve, Olli; Salo, Simo; Verta, Matti; Forsius, John

2003-08-01

River Kymijoki, the fourth largest river in Finland, has been heavily polluted by pulp mill effluents as well as by chemical industry. Loading has been reduced considerably, although remains of past emissions still exist in river sediments. The sediments are highly contaminated with polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated diphenyl ethers (PCDEs), and mercury originating from production of the chlorophenolic wood preservative (Ky-5) and other sources. The objective of this study was to simulate the transport of these PCDD/F compounds with a one-dimensional flow and transport model and to assess the impact of restoration dredging. Using the estimated trend in PCDD/F loading, downstream concentrations were calculated until 2020. If contaminated sediments are removed by dredging, the temporary increase of PCDD/F concentrations in downstream water and surface sediments will be within acceptable limits. Long-term predictions indicated only a minor decrease in surface sediment concentrations but a major decrease if the most contaminated sediments close to the emission source were removed. A more detailed assessment of the effects is suggested.

Internal standards for use in the comprehensive analysis of polychlorinated aromatic hydrocarbons using gas chromatography combined with multiphoton ionization mass spectrometry.

PubMed

Li, Adan; Imasaka, Totaro

2016-10-28

To decrease health-risks to humans, non-toxic compounds were evaluated for use as internal standards for calibrating data obtained by gas chromatography/multiphoton ionization mass spectrometry (GC-MPI-MS) using an ultraviolet femtosecond laser as the ionization source. The retention time in the mass chromatogram was calibrated using a retention index, in which a series of n-alkanes was employed as internal standards for evaluating the retention times for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs). To compensate for changes in signal intensity in MPI-MS, the dependence of signal intensity on the laser pulse energy was investigated for the dioxin-like compounds, in addition to five non-toxic aromatic hydrocarbons, that were used as internal standards. Based on their similar behavior,the non-toxic PCDD/PCDF, its 13 C-isotope, and pentachlorobenzene behave similarly, we conclude that they can be used for calibrating the signal intensities in MPI-MS. Copyright © 2016 Elsevier B.V. All rights reserved.

Influence of process changes on PCDD/Fs produced in an iron ore sintering plant

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

Guerriero, E.; Bianchini, M.; Gigliucci, P.F.

2009-01-15

This study investigated the influence of different charge typologies and additives on the PCDD/Fs amount produced and on the congener profiles in an iron ore sintering plant. Many tests were carried out combining different typologies of charge (iron materials) and solid fuel ('coke breeze' or 'anthracite') with or without the use of urea. The PCDD/Fs produced ranged from 1.2 to 22.7 {mu} g I-TEQ/ton of agglomerate, whereas the PCDD/Fs released to the ambient air ranged from 0.10 to 1.92 ng I-TEQ/Nm{sup 3} because of cleaning in an electrostatic precipitator (ESP) and a Wetfine scrubber (WS). A more homogeneous charge withmore » a higher amount of fine particles charge appeared to produce a lower PCDD/Fs concentration due to a better combustion but this hypothesis needs further investigations on charges having different dimension particles. Only a synergitic action of urea and anthracite was able to reduce the high PCDD/Fs content due to the bad combustion of the more inhomogeneous charge with a lower amount of fine particles. The congener profile was a typical combustion process fingerprint because the PCDFs predominated, the highly chlorinated congeners (HeptaCDD and OctaCDD) prevailed in PCDDs, whereas in PCDFs the profile was more varied; 1,2,3,4,6,7,8-HeptaCDF was the main contributor to the total concentration while 2,3,4,7,8-PentaCDF was the main contributor to the I-TEQ concentration. Whereas all the parameters under scrutiny influenced strongly the amount of PCDD/Fs produced, they affected only slightly the fingerprint of PCDD/Fs. In all cases studied, the reduction obtained using urea, anthracite, or the more homogeneous charge with a higher amount of fine particles was slightly greater on the higher chlorinated congeners in respect to the lower ones.« less

Human dietary exposure to polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in Taiwan.

PubMed

Wang, I-Ching; Wu, Yee-Lin; Lin, Long-Full; Chang-Chien, Guo-Ping

2009-05-30

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) levels in a total of 25 food items in Taiwan were surveyed. It was observed that shellfish and saltwater fish possessed the highest PCDD/Fs levels, 9.82 and 3.60 pg WHO-TEQ/g, respectively, on the lipid basis. The dietary intakes of humans at the ages of 12-18, 19-64, and over 65 were determined. The estimated intake were between 21.8 pg (female teenagers) and 37.6 pg (male seniors) WHO-TEQ/day; the levels varied with the dietary habits. The PCDD/F intakes for all human groups are far below the tolerable limit of 70 pg WHO-TEQ/kg b.w./month. In addition, the daily PCDD/F intake levels for duck-farmers consuming average and large amounts of PCDD/F contaminated duck eggs were examined. The result shows that consuming more than one duck egg with level higher than 10 pg WHO-TEQ/g lipid of PCDD/Fs per day could lead to a PCDD/F intake level higher than the tolerable limit. However, for normal population, there is a little risk to ingest intolerable amount of PCDD/Fs because of consuming contaminated duck eggs.

Inventory of U.S. 2012 dioxin emissions to atmosphere.

PubMed

Dwyer, Henri; Themelis, Nickolas J

2015-12-01

In 2006, the U.S. EPA published an inventory of dioxin emissions for the U.S. covering the period from 1987-2000. This paper is an updated inventory of all U.S. dioxin emissions to the atmosphere in the year 2012. The sources of emissions of polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), collectively referred to in this paper as "dioxins", were separated into two classes: controlled industrial and open burning sources. Controlled source emissions decreased 95.5% from 14.0 kg TEQ in 1987 to 0.6 kg in 2012. Open burning source emissions increased from 2.3 kg TEQ in 1987 to 2.9 kg in 2012. The 2012 dioxin emissions from 53 U.S. waste-to-energy (WTE) power plants were compiled on the basis of detailed data obtained from the two major U.S. WTE companies, representing 84% of the total MSW combusted (27.4 million metric tons). The dioxin emissions of all U.S. WTE plants in 2012 were 3.4 g TEQ and represented 0.54% of the controlled industrial dioxin emissions, and 0.09% of all dioxin emissions from controlled and open burning sources. Copyright © 2015. Published by Elsevier Ltd.

Dioxin concentrations in breast milk of Vietnamese nursing mothers: a survey four decades after the herbicide spraying.

PubMed

Tai, Pham The; Nishijo, Muneko; Kido, Teruhiko; Nakagawa, Hideaki; Maruzeni, Shoko; Naganuma, Rie; Anh, Nguyen Thi Nguyet; Morikawa, Yuko; Luong, Hoang Van; Anh, Tran Hai; Hung, Nguyen Ngoc; Son, Le Ke; Tawara, Kenji; Nishijo, Hisao

2011-08-01

In an operation by United States Armed Forces during 1961 to 1971, large quantities of herbicides were sprayed in South Vietnam. These herbicides contained 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-tetraCDD), the most toxic congener of dioxins. Several decades after the herbicide spraying ceased, dioxin concentrations in the environment and human remained elevated in the sprayed areas. Breast milk samples from 520 nursing mothers residing in areas including the hot spots as well as the sprayed and unsprayed areas were collected to quantify the levels of dioxins. The total toxic equivalents of 2,3,7,8-substitued PCDDs/PCDFs in breast milk of mothers living in the hot spots, and the sprayed and unsprayed areas were 14.10 pg/g lipid, 10.89 pg/g lipid, and 4.09 pg/g lipid for primiparae and 11.48 pg/g lipid, 7.56 pg/g lipid, and 2.84 pg/g lipid for multiparae, respectively, with significant differences in the values among the three areas. In the hot spots, dioxin levels were highly correlated with the residency of mothers after adjustment for their age and parity.

Emissions from an automobile fire.

PubMed

Lönnermark, Anders; Blomqvist, Per

2006-02-01

The emissions from automobile fires have been investigated. The main gas phase components were analysed in small-scale tests with representative material from an automobile. A more detailed investigation of full-scale simulated automobile fires was also conducted, including the characterisation of gas phase components, particulates and run-off water from extinguishing activities. Three separate full scale fire tests have been characterised: a fire ignited and developed in the engine compartment; a fire ignited inside the coupé, that was extinguished in the early stages; and a similar fire ignited inside the coupé that was allowed to spread until the entire vehicle was involved in the fire. The quantitative analysis of the smoke gases from the full-scale fires showed that emissions with a potentially negative impact on the environment, or chronic toxic effect on humans, were produced in significant quantities. These emissions included HCl, SO2, VOCs (e.g. benzene), PAHs, and PCDDs/PCDFs. Analysis of run-off water indicated that it was severely contaminated, containing elevated levels of both organic compounds and metals. Comparison with data from other vehicle fires found in the literature shows that contamination by lead, copper, zinc, and antimony appears to be significant in water run-off from these types of fires.

Serum profiles of PCDDs and PCDFs, in individuals near the Escambia Wood Treating Company Superfund site in Pensacola, FL.

PubMed

Karouna-Renier, Natalie K; Rao, K Ranga; Lanza, John J; Davis, Deeya A; Wilson, Patricia A

2007-10-01

The Escambia Wood Treating Company (ETC) Superfund site, Pensacola, FL, is contaminated with polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F), benzo(a)pyrene, lead and arsenic from pentachlorophenol (PCP), creosote, and other compounds used to treat utility poles and foundation pilings. Although ETC's operations ceased in 1982, soils in the areas surrounding the facility continue to exhibit elevated levels of contaminants attributable to ETC operations. In July 2000, individuals who may have been affected by contamination from the ETC site, including current and former residents and former workers and their household members were invited to participate in a study, which included a health and exposure history and routine blood analysis. We also conducted a toxicological health evaluation of a subset of these eligible workers/residents by analyzing serum levels of 17 PCDD/F congeners. Members of the ETC cohort exhibited elevated serum PCDD/F relative to the general population, and congener profiles in members of the cohort reflected patterns commonly observed in persons exposed to PCP. Hypertension prevalence in the cohort was found to correlate with PCDD/F levels, although no other significant relationships were identified with monitored health indices.

Application of a novel large-volume injection method using a stomach-shaped inlet liner in capillary gas chromatographic trace analysis of dioxins in human milk and plasma.

PubMed

Saito, Koichi; Ohmura, Atsuko; Takekuma, Mikiko; Sasano, Ryoichi; Matsuki, Yasuhiko; Nakazawa, Hiroyuki

2007-06-01

A newly developed large-volume injection (LVI) technique that employs a unique stomach-shaped inlet liner (SSIL) inside of a programmable temperature vaporizer was used for the determination of trace amounts of dioxins in human milk and plasma. The initial temperature and the initial dwelling time of the inlet and the kind of solvent used were found to be critical in determining the analytical sensitivity of dioxins due to the loss of these relatively volatile compounds during solvent vaporization. Human milk and plasma were purified and fractionated by pre-packed multi-layered silica-gel chromatography and activated carbon silica-gel column chromatography. A 20-microL aliquot of the fraction collected from the chromatography with toluene was directly applied to the LVI system in high-resolution gas chromatography/high-resolution mass spectrometry. Excellent correlation (r > 0.97) between the values obtained by the LVI method using the SSIL device and those by the conventional regular-volume splitless injection method was obtained for PCDDs, PCDFs and non-ortho PCBs in human milk and plasma samples.

Development of supercritical carbon dioxide extraction with a solid phase trap for dioxins in soils and sediments.

PubMed

Miyawaki, Takashi; Kawashima, Ayato; Honda, Katsuhisa

2008-01-01

A method involving supercritical fluid extraction (SFE) with a solid phase trap containing activated alumina was investigated for the rapid analysis of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin like polychlorinated biphenyls (DL-PCBs) in soils and sediments. The samples were extracted by using supercritical carbon dioxide with water (2% versus CO(2) flow velocity) being used as an entrainer at a pressure of 30 MPa and a temperature of 130 degrees C for 50 min. The extracts were adsorbed on an activated alumina trap that was maintained at a temperature of 150 degrees C, and then, PCDD/DFs and DL-PCBs were eluted with 20 ml of hexane at 60 degrees C. After concentration, they were measured with a high-resolution gas chromatograph interfaced to a high-resolution mass spectrometric detector. The average concentrations of PCDD/DFs and DL-PCBs corresponded to the results obtained by the conventional method, and the reproducibility of this SFE method was below 21% of the relative standard deviations for all samples. The total time required for the analysis of the pretreatment of this method was only 2 h.

DFT study of the adsorption of 2,3,7,8-tetrachlorodibenzo-p-dioxin on pristine and Ni-doped boron nitride nanotubes.

PubMed

Wang, Ruoxi; Zhang, Dongju; Liu, Chengbu

2017-02-01

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are highly toxic to humans and the environment. Developing efficient methods to detect or remove these pollutants is particularly important and urgent. Boron nitride nanotubes (BNNTs) with low dimension and high surface-to-volume ratio might be one of promising materials for the adsorption of PCDD/Fs. Here we present a density functional theory (DFT) study on the interaction of the pristine and Ni doped (8,0) single-walled BNNTs with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the most toxic congener among PCDD/F family. The calculated results show that the pristine BNNT intrinsically interacts with TCDD via physisorption with π-π stacking interaction, in contrast, the Ni-doped BNNT presents much higher reactivities toward TCDD. The impurity Ni atom plays a crucial role for capturing TCDD molecule. We also find that the Ni doping introduces the local electronic states within the band gap of the BNNT and induces magnetism in the doped systems. The present results are expected to provide useful guidance for the potential application of BNNTs as adsorption materials for detecting or removing dioxin pollutants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Contaminant concentrations and biomarker response in great blue heron eggs from 10 colonies on the upper Mississippi River, USA

USGS Publications Warehouse

Custer, T.W.; Hines, R.K.; Melancon, M.J.; Hoffman, D.J.; Wickliffe, J.K.; Bickham, J.W.; Martin, J.W.; Henshel, D.S.

1997-01-01

In 1993, great blue heron (Ardea herodias; GBH) eggs were collected from 10 colonies on the upper Mississippi River (UMR). They were then artificially incubated until pipping and analyzed for mercury, selenium, and organochlorines. Livers of embryos were analyzed for hepatic microsomal ethoxyresorufin-O-dealkylase (EROD) and four measures of oxidative stress. Brains were measured for asymmetry and blood was measured for the coefficient of variation of DNA (DNA VC). Organochlorine concentrations were generally low (geometric mean DDE = 1.3 ug/g wet weight; polychlorinated biphenyl [PCB] = 3.0 ug/g; 2,3,7,8-tetrachloro- -dioxin [TCDD] = 11.5 pg/g). Eggshell thickness was negatively correlated with DDE concentrations. Mercury (geometric mean = 0.8 ug/g dry weight) and selenium (3.1 ug/g dry weight) concentrations in GBH eggs were within background levels. EROD activity was not correlated with total PCBs, TCDD or toxic equivalents (TEQs) based on the relative contribution of individual PCB congeners, dibenzodioxins (PCDDs), and dibenzofurans (PCDFs) to calculated TEQs. Three of the four measures of oxidative stress were correlated with mercury concentrations. Twenty of 43 (47%) embryo brains were asymmetrical and the embryos with asymmetrical brains had higher EROD concentrations in the liver and higher DNA CV in the blood than embryos with symmetrical brains.

Dioxins and polyvinylchloride in combustion and fires.

PubMed

Zhang, Mengmei; Buekens, Alfons; Jiang, Xuguang; Li, Xiaodong

2015-07-01

This review on polyvinylchloride (PVC) and dioxins collects, collates, and compares data from selected sources on the formation of polychlorinated dibenzofurans (PCDFs) and dibenzo-p-dioxins (PCDDs), or in brief dioxins, in combustion and fires. In professional spheres, the incineration of PVC as part of municipal solid waste is seldom seen as a problem, since deep flue gas cleaning is required anyhow. Conversely, with its high content of chlorine, PVC is frequently branded as a major chlorine donor and spitefully leads to substantial formation of dioxins during poorly controlled or uncontrolled combustion and open fires. Numerous still ill-documented and diverse factors of influence may affect the formation of dioxins during combustion: on the one hand PVC-compounds represent an array of materials with widely different formulations; on the other hand these may all be exposed to fires of different nature and consequences. Hence, attention should be paid to PVC with respect to the ignition and development of fires, as well as attenuating the emission of objectionable compounds, such as carbon monoxide, hydrogen chloride, polycyclic aromatic hydrocarbons, and dioxins. This review summarises available dioxin emissions data, gathers experimental and simulation studies of fires and combustion tests involving PVC, and identifies and analyses the effects of several local factors of influence, affecting the formation of dioxins during PVC combustion. © The Author(s) 2015.

Occurrence, variability and human exposure to Polychlorinated Dibenzo-p-dioxins (PCDDs), Polychlorinated Dibenzofurans (PCDFs) and Dioxin-Like Polychlorinated Biphenyls (DL-PCBs) in dairy products from Chile during the 2011-2013 survey.

PubMed

Pizarro-Aránguiz, N; Galbán-Malagón, C J; Ruiz-Rudolph, P; Araya-Jordan, C; Maddaleno, A; San Martin, B

2015-05-01

Levels, congener profiles of PCDD/Fs, DL-PCBs and human exposure for these xenobiotics never have been reported in Chile. For that purpose 102 raw cow milk samples were collected from seven different regions of Chile during 2011 until 2013. The highest mean level for PCDD/Fs, corresponds to 0.32 pg WHO-TEQ2005 g(-1) fat (2012) and for DL-PCBs 0.17 pg WHO-TEQ2005 g(-1) fat (2011), using the upper bound approach. Penta and tetra chlorinated congeners dominated PCDD/Fs profiles in a WHO-TEQ2005 basis during the survey. In the case of DL-PCBs, PCB 126 dominated the profiles with 89%. Statistical analysis showed significant difference among years only in DL-PCBs residues. Also dietary intake was estimated, and the highest level for total sum of PCDD/Fs and DL-PCBs for adult was 0.16 pg WHO-TEQ kg(-1) b.w d(-1) (2011) and for children correspond to 0.65 pg WHO-TEQ kg(-1) b.wd(-1) (2011). Concentrations and dietary intake for the studied compounds in milk and butter samples were below international and national regulations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Patterns, trends, and toxicological significance of chlorinated hydrocarbon and mercury contaminants in bald eagle eggs from the Pacific coast of Canada, 1990-1994.

PubMed

Elliott, J E; Norstrom, R J; Smith, G E

1996-10-01

Bald eagle (Haliaeetus leucocephalus) eggs were collected during incubation, 1990-1992, from 16 nests near three bleached-kraft pulp mills, from six nests in the Fraser River estuary and from seven nests at a reference site on the Pacific coast of Canada. Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were present in all eggs in a qualitatively similar pattern among sites. Mean concentrations of 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD) were significantly higher in eggs collected from near three kraft pulp mill sites in the Strait of Georgia (44, 45, 84 ng/kg) than from the reference area in Johnstone Strait (15 ng/kg). There were few differences among sites in mean organochlorine pesticide levels, indicating the diffuse distribution of those chemicals and the domination of atmospheric inputs. Mean concentrations of total polychlorinated biphenyls (PCBs) were highest in eggs from the Strait of Georgia (4.86 mg/kg) and the PCB congener pattern was significantly different between that area and both the lower Fraser valley and Johnstone Strait. Mean mercury concentrations, which were mainly methyl-mercury, were significantly higher in eggs collected from the lower Fraser Valley (0.258 mg/kg) and Johnstone Strait (0.294 mg/kg) compared to the Strait of Georgia (0.188 mg/kg). Individual and regional variation in concentrations of organochlorine pesticides, PCBs and mercury in eagle eggs were thought to be influenced mainly by dietary differences. Toxicologically, in 1990, mean TCDD-toxic equivalents (TEQs) in bald eagle eggs were about two-fold greater than a lowest-observed-effect level, suggested elsewhere for this species, of 210 ng/kg TEQs. In the Strait of Georgia, PCCDs and PCDFs made a greater contribution to TEQs than non-ortho and mono-ortho PCBs, whereas the reverse was true for eggs outside the strait. Mean eggshell thickness was less than the pre-1947 value at all sites, although there was no significant relationship between eggshell thickness and DDE concentrations. Levels of other organochlorine pesticides and mercury were below those considered to be toxic.

Evidence of Spatially Extensive Resistance to PCBs in an Anadromous Fish of the Hudson River

PubMed Central

Yuan, Zhanpeng; Courtenay, Simon; Chambers, R. Christopher; Wirgin, Isaac

2006-01-01

Populations of organisms that are chronically exposed to high levels of chemical contaminants may not suffer the same sublethal or lethal effects as naive populations, a phenomenon called resistance. Atlantic tomcod (Microgadus tomcod) from the Hudson River, New York, are exposed to high concentrations of polycyclic aromatic hydrocarbons (PAHs) and bioaccumulate polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs). They have developed resistance to PCBs and PCDDs but not to PAHs. Resistance is largely heritable and manifests at early-life-stage toxic end points and in inducibility of cytochrome P4501A (CYP1A) mRNA expression. Because CYP1A induction is activated by the aryl hydrocarbon receptor (AHR) pathway, as are most toxic responses to these compounds, we sought to determine the geographic extent of resistance to CYP1A mRNA induction by PCBs in the Hudson River tomcod population. Samples of young-of-the-year tomcod were collected from seven locales in the Hudson River, extending from the Battery at river mile 1 (RM 1) to RM 90, and from the Miramichi River, New Brunswick, Canada. Laboratory-reared offspring of tomcod adults from Newark Bay, in the western portion of the Hudson River estuary, were also used in this study. Fish were partially depurated in clean water and intraperitoneally injected with 10 ppm coplanar PCB-77, 10 ppm benzo[a]pyrene (BaP), or corn oil vehicle, and levels of CYP1A mRNA were determined. CYP1A was significantly inducible by treatment with BaP in tomcod from the Miramichi River, from laboratory-spawned offspring of Newark Bay origin, and from all Hudson River sites spanning 90 miles of river. In contrast, only tomcod from the Miramichi River displayed significantly induced CYP1A mRNA expression when treated with PCB-77. Our results suggest that the population of tomcod from throughout the Hudson River estuary has developed resistance to CYP1A inducibility and probably other toxicities mediated by the AHR pathway. Tomcod from the Hudson River may represent the most geographically expansive population of vertebrates with resistance to chemical pollutants that has been characterized. PMID:16393662

Effects of cooking on concentrations of polychlorinated dibenzo-p-dioxins and related compounds in fish and meat.

PubMed

Hori, Tsuguhide; Nakagawa, Reiko; Tobiishi, Kazuhiro; Iida, Takao; Tsutsumi, Tomoaki; Sasaki, Kumiko; Toyoda, Masatake

2005-11-02

We investigated the cooking-induced changes in concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) (dioxins) using mackerel and beef. The concentrations of dioxins (29 congeners) were determined by isomer specific analyses and were compared between uncooked and cooked samples. The cooking procedures examined in this study included grilling as a fillet, boiling as a fillet, and boiling as tsumire (small, hand-rolled balls) for mackerel and boiling as a slice, broiling as a slice, and broiling as a hamburger for beef. Three trials were carried out for each cooking method. Generally, concentrations of dioxins were reduced in every cooking trial. When nondetected congener concentrations were assumed to be half the limit of detection for mackerel, the maximum percentage reductions of total concentrations given as 2,3,7,8-tetraCDD equivalents (TEQ) were 31% in grilling as a slice, 14% in boiling as a slice, and 21% in boiling as tsumire under the conditions of this study. In contrast, for beef, the reductions were 42% in boiling as a slice, 42% in broiling as a slice, and 44% in broiling as a hamburger. These results suggest that ordinary cooking processes with heating undoubtedly reduce the dioxin content in animal products, and the reductions estimated should be considered when dioxin intake is evaluated using contamination data for individual food items.

Chlorinated dibenzo-P-dioxins and dibenzofurans and the human immune system (2) In vitro proliferation of lymphocytes from workers with quantified moderately-increased body burdens

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

Neubert, R.; Maskow, L.; Delgado, I.

1995-11-01

Lymphocyte proliferation responses were studied in workers with moderately increased body burdens of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin and other polychlorinated dibenzo-p-dioxin and other polyclorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs), calculated as International Toxicity Equivalencies [I-TE]. Mitogens (pokeweed mitogen [PWM], phytohemagglutinine [PHA], concanavalin A [Con A], as well as anti-human monoclonal antibody against CD3 were used as proliferation stimulators in vitro. Additionally, the feasibility of using the lymphocyte response to tetanus toxoid was assessed, and the response to this recall-antigen was included in this trial. No decrease in the capacity of {sup 3}H-thymidine incorporation was observed with any of the proliferation stimulatorsmore » in the group of volunteers with the increased TCDD-body burden when compared with volunteers exhibiting TCDD-concentrations in blood flat within the reference range. Regression analysis revealed a slight trend towards an increase for {sup 3}H-thymidine incorporation during the stimulation with PHA only. It can be concluded from our data that moderates increases in the TCDD- or I-TE-body burdens do not induce any medically significant changes in the capacity for proliferation of lymphocytes, measured as {sub 3}H=thymidine incorporation. 25 refs., 5 figs., 3 tabs.« less

Characterization of the Particulate Emissions from the BP ...

EPA Pesticide Factsheets

Opportunistic particle samples were gathered from the sail of a tethered aerostat during at-sea plume sampling of the purposely-burned surface oil during the BP Deepwater Horizon disaster in the Gulf of Mexico. Particles were analyzed for polycyclic aromatic hydrocarbons (PAHs), organic carbon (OC), elemental carbon (EC), metals, and polychlorinated dibenzodioxins/dibenzofurans (PCDDs/PCDFs). Emission factors were calculated using previous sampling values of background-adjusted CO2 and particulate matter (PM)-bound C. The mean of five thermal-optical analyses indicated that the burned crude oil particulate matter was 93% carbon (w/w) with the predominance being refractory elemental carbon (82% w/w) on average. PAHs accounted for roughly 60 ug/g of the PM mass or 4.5 mg/kg oil burned, at least an order of magnitude less than earlier laboratory based studies. Microscopy indicates that the soot from the in situ oil burns is distinct from more common soot by its aggregate size, primary particle size, and nanostructure within the primary particles. The PCDD/PCDF concentration of the PM was 1.5 to 3.3 ng toxic equivalency (TEQ)/kg PM sampled, about 10-fold lower than from a previous dedicated gas/solid sample, indicating loss of small particle-bound and more volatile PCDD/PCDF congeners through the aerostat sail. This work presents an analysis of smoke particles opportunistically caught during the in situ surface oil burns during the 2010 BP Deepwater Horizon di

MICRO AUTO GASIFICATION SYSTEM: EMISSIONS ...

EPA Pesticide Factsheets

A compact, CONEX-housed waste to energy unit, Micro Auto Gasification System (MAGS), was characterized for air emissions from burning of military waste types. The MAGS unit is a dual chamber gasifier with a secondary diesel-fired combustor. Eight tests were conducted with multiple waste types in a 7-day period at the Kilauea Military Camp in Hawai’i. The emissions characterized were chosen based on regulatory emissions limits as well as their ability to cause adverse health effects on humans: particulate matter (PM), mercury, heavy metals, volatile organic compounds (VOCs), polyaromatic hydrocarbons (PAHs), and polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Three military waste feedstock compositions reflecting the variety of wastes to be encountered in theatre were investigated: standard waste (SW), standard waste with increased plastic content (HP), standard waste without SW food components but added first strike ration (FSR) food and packaging material (termed FSR). A fourth waste was collected from the Kilauea dumpster that served the dining facility and room lodging (KMC). Limited scrubber water and solid ash residue samples were collected to obtain a preliminary characterization of these effluents/residues.Gasifying SW, HP, and KMC resulted in similar PCDD/PCDF stack concentrations, 0.26-0.27 ng TEQ/m3 at 7% O2, while FSR waste generated a notably higher stack concentration of 0.68 ng TEQ/m3 at 7% O2. The PM emission

Emission of PCDD/F, PCB, and HCB from combustion of firewood and pellets in residential stoves and boilers.

PubMed

Hedman, Björn; Naslund, Morgan; Marklund, Stellan

2006-08-15

To assess potential emissions of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and hexachlorobenzene (HCB) from residential combustion of biofuels, experiments were performed in which various types of pellets and firewood were combusted in four types of stoves and boilers, with both full and reduced rates of air supply. Intermittent combustion of wood pellets resulted in emissions of 11 ng-(WHO-TEQ)/kg combusted fuel (dry weight). A modern, environmentally certified boiler yielded somewhat lower emissions of PCCD/F and PCB than a wood stove. Both gave <0.1 ng(WHO-TEQ)/m3n (1.3-6.5 ng(WHO-TEQ)/kg) and considerably lower emissions than an old boiler (7.0-13 ng(WHO-TEQ)/kg). No positive effect on emissions could be observed in full air combustion (simulating the use of a heat storage tank) compared to combustion with reduced air. Two of the wood combustion experiments included paper and plastic waste fuels. Chlorine-containing plastic waste gave rise to high emissions: ca. 310 ng(WHO-TEQ)/ kg over the whole combustion cycle. The homologue profiles of PCDD/Fs show characteristic differences between ashes and flue gas from combustions with different levels of air supply. These differences do not, however, seem to have any correlation to the relative amount of toxic congeners.

Occurrence of Polychlorinated Dibenzo-p-Dioxins and Dibenzofurans and Polychlorinated Biphenyls in Fruit and Vegetables from the "Land of Fires" Area of Southern Italy.

PubMed

Esposito, Mauro; De Roma, Antonella; Cavallo, Stefania; Diletti, Gianfranco; Baldi, Loredana; Scortichini, Giampiero

2017-11-10

The concentrations of polychlorinated dibenzo- p -concentrations dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) (PCDD/Fs), and polychlorinated biphenyls (PCBs) were determined in fruit and vegetables collected in farms located in the well-known "Land of Fires" area of Southern Italy, in an effort to learn more about the environmental pollution of this high-risk area due to illegal waste dumping and uncontrolled burning near cultivated fields. Concentrations were in the range 0.011-2.26 ng g -1 for the six "indicator" non-dioxin-like PCBs (NDL-PCBs), and 0.0009-0.096 pg WHO toxic equivalent (TEQ) g -1 for the sum of dioxin-like PCBs (DL-PCBs) and PCDD/Fs. Lacking maximum limits for these contaminants in fruit and vegetables, the concentration values found were compared with the action levels set out in the EU Recommendations. These levels were never exceeded in the examined samples. In the present study, the highest mean value for PCDD/Fs + DL-PCB corresponded to apricots, olives, and nuts, while the lowest values were observed in endive and green beans. The results showed also that NDL-PCB levels in apricots were much higher than in any other food, suggesting that they can accumulate PCBs: this fruit might be proposed as a "sentinel" of the presence of these contaminants in the environment.

Role of black carbon in the sorption of polychlorinated dibenzo-p-dioxins and dibenzofurans at the Diamond Alkali superfund site, Newark Bay, New Jersey.

PubMed

Lambert, Matthew K; Friedman, Carey; Luey, Pamela; Lohmann, Rainer

2011-05-15

The sorption of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) to organic carbon (OC) and black carbon (BC) was measured in two sediment cores taken near the Diamond Alkali superfund site (DA) in the Passaic River and Newark Bay, New Jersey (U.S.A.). An OC partitioning model and a BC-inclusive, Freundlich distribution model were used to interpret measurements of freely dissolved PCDD/Fs using passive samplers in sediment incubations, together with measured sedimentary concentrations of OC, BC, and PCDD/Fs. Samples were also analyzed for polycyclic aromatic hydrocarbons (PAHs) as controls on the two distribution models. The OC partitioning model underpredicted the distribution of PAHs and PCDD/Fs by 10-100-fold. The Freundlich model predicted the distribution of PAHs at the DA to within a factor of 2-3 of observations. Black carbon-water partition coefficients (K(iBC)) for PCDD/Fs, derived from literature results of both field and laboratory studies differed up to 1000-fold from values derived from this study. Contrary to expectations, PCDDs displayed stronger sorption than either PCDFs or PAHs relative to their subcooled liquid aqueous solubilities. Even though the presence of BC in the sediments reduced the overall bioavailability of PCDD/Fs by >90%, the sediments at 2 m depth continue to display the highest pore water activities of PCDD/Fs.

Developing risk-based screening guidelines for dioxin management at a Melbourne sewage treatment plant.

PubMed

Gorman, J; Mival, K; Wright, J; Howell, M

2003-01-01

Dioxin is a generic term used to refer to the congeners of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The principal source of dioxin production is generally thought to be from unintended by-products of waste incineration, but dioxins are also naturally formed from volcanic activity and forest fires (WHO, 1998). Estimates of dioxin emissions in Australia suggest that approximately 75% of the total PCDD and PCDF emissions derive from prescribed burning and wild bushfires. Currently, no screening guidelines for dioxins within soils are available in Australia. This paper presents the general approach and results of a human health risk-based assessment performed by URS Australia in 2001 to develop site specific reference criteria for remediation of a former sewage plant in Melbourne. Risk-based soil remediation concentrations for dioxins at the sewage treatment plant site were developed using tolerable daily intake values of 4, 2 and 1 pg/kg/day. The potentially significant exposure pathways and processes for exposure to dioxins were identified and risk-based soil concentrations derived in accordance with the general method framework presented in the National Environmental Protection Measure (Assessment of Site Contamination). The derived dioxin reference criteria were used to develop an effective risk management program focussed on those conditions that present the greatest contribution to overall risk to human health.

Levels and trends of PCDD/Fs and PCBs in camel milk (Camelus bactrianus and Camelus dromedarius) from Kazakhstan.

PubMed

Konuspayeva, Gaukhar; Faye, Bernard; De Pauw, Edwin; Focant, Jean-François

2011-10-01

To date, despite the fact it represents a very important part of the national dairy production, no data are available concerning the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) in camel milk from the Republic of Kazakhstan. Selected PCDDs, PCDFs, and PCBs were measured in pools of milk from camels (n=15) located in various places of Kazakhstan (Almaty, Atyrau, Aralsk, Shymkent) and sampled at two different seasons for two different species (Camelus bactrianus and Camelus dromedarius). Non-dioxin-like (NDL-)PCB concentrations (6.3±2.7 ng g(-1) fat, median 5.1 ng g(-1) fat, range 0.6-17.4 ng g(-1) fat) were far below the maximum value of 40 ng g(-1) fat proposed by the EU. Dioxin-like (DL-)PCB concentrations (1.7±0.7 ng g(-1) fat, median 1.5 ng g(-1) fat, range 0.3-4.2 ng g(-1) fat) and the NDL-PCB to DL-PCB ratio (4.3) were similar to what is reported in EU for cow-based dairy products. PCB 52 and PCB 101 appeared to be proportionally more present in Kazakh camel milk samples (>60% of the sum of the 6 indicator NDL-PCBs) than in European cow milk samples (<10% of the sum of the 6 indicator NDL-PCBs), indicating possible differences in the route of exposure to PCBs in Kazakhstan. PCB 105 and PCB 118 appeared to be present at higher concentrations in camel milk (>80% of the sum of the 12 DL-PCBs). PCB 105, PCB 118 and PCB 156 were the major congeners for DL-PCBs, accounting for 92% of the sum of concentrations of DL-PCBs (88% for Belgian cows). In terms of TEQ, PCB 126 and PCB 118 are the major contributors and represent, respectively, 80% and 14% of the DL-PCB TEQWHO05 concentrations. No significant interracial or geographical trends were observed for NDL- and DL-PCB profiles. However, concentrations of all DL-PCBs appeared to be significantly higher for samples collected in Atyrau region. 2,3,7,8-TCDD level (mean 0.08±0.07 pg g(-1) fat, median 0.08 pg g(-1) fat, range 0.00-0.18 pg g(-1) fat, 60%>LOQs) were very low for all samples and 2,3,4,7,8-PeCDF was the major contributor (27%) to the PCDD/F TEQWHO05. Considering the total TEQWHO05 (sum of DL-PCBs and PCDD/Fs), DL-PCB and PCDD/F contributed for 73% and 27%, respectively. A decrease of only 1% of the total TEQ was observed when using the TEFWHO05 scale instead of the TEFWHO98 scale. Two samples collected in the region of Atyrau exceeded the EU maximum level value of 6.00 pg TEQWHO98 g(-1) fat (6.4 pg TEQWHO05 g(-1) fat and 6.9 pg TEQWHO05 g(-1) fat). Both samples exceeded the EU action level for the sum of DL-PCBs. Based on the fact that camel milk is used to prepare popular traditional fermented drinks like shubat, this suggests that the human exposure in the Caspian Sea region of Atyrau should be expected to be higher than in the other regions studied here. Copyright © 2011 Elsevier Ltd. All rights reserved.

Urinary Amino Acid Alterations in 3-Year-Old Children with Neurodevelopmental Effects due to Perinatal Dioxin Exposure in Vietnam: A Nested Case-Control Study for Neurobiomarker Discovery

PubMed Central

Nishijo, Muneko; Tai, Pham The; Anh, Nguyen Thi Nguyet; Nghi, Tran Ngoc; Nakagawa, Hideaki; Van Luong, Hoang; Anh, Tran Hai; Morikawa, Yuko; Waseda, Tomoo; Kido, Teruhiko; Nishijo, Hisao

2015-01-01

In our previous study of 3-year-old children in a dioxin contamination hot spot in Vietnam, the high total dioxin toxic equivalent (TEQ-PCDDs/Fs)-exposed group during the perinatal period displayed lower Bayley III neurodevelopmental scores, whereas the high 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-exposed group displayed increased autistic traits. In autistic children, urinary amino acid profiles have revealed metabolic alterations in the amino acids that serve as neurotransmitters in the developing brain. Therefore, our present study aimed to investigate the use of alterations in urinary amino acid excretion as biomarkers of dioxin exposure-induced neurodevelopmental deficits in highly exposed 3-year-old children in Vietnam. A nested case-control study of urinary analyses was performed for 26 children who were selected from 111 3-year-old children whose perinatal dioxin exposure levels and neurodevelopmental status were examined in follow-up surveys conducted in a dioxin contaminated hot spot. We compared urinary amino acid levels between the following 4 groups: (1) a high TEQ-PCDDs/Fs and high TCDD-exposed group; (2) a high TEQ-PCDDs/Fs but low TCDD-exposed group; (3) a low TEQ-PCDDs/Fs exposed and poorly developed group; and (4) a low TEQ-PCDDs/Fs exposed and well-developed group. Urinary levels of histidine and tryptophan were significantly decreased in the high TEQ-PCDDs/Fs and high TCDD group, as well as in the high TEQ-PCDDs/Fs but low TCDD group, compared with the low TEQ-PCDDs/Fs and well-developed group. However, the ratio of histidine to glycine was significantly lower only in the high TEQ-PCDDs/Fs and high TCDD group. Furthermore, urinary histidine levels and the ratio of histidine to glycine were significantly correlated with neurodevelopmental scores, particularly for language and fine motor skills. These results indicate that urinary histidine is specifically associated with dioxin exposure-induced neurodevelopmental deficits, suggesting that urinary histidine may be a useful marker of dioxin-induced neurodevelopmental deficits and that histaminergic neurotransmission may be an important pathological contributor to dioxin-mediated neurotoxicity. PMID:25584822

Urinary amino acid alterations in 3-year-old children with neurodevelopmental effects due to perinatal dioxin exposure in Vietnam: a nested case-control study for neurobiomarker discovery.

PubMed

Nishijo, Muneko; Tai, Pham The; Anh, Nguyen Thi Nguyet; Nghi, Tran Ngoc; Nakagawa, Hideaki; Van Luong, Hoang; Anh, Tran Hai; Morikawa, Yuko; Waseda, Tomoo; Kido, Teruhiko; Nishijo, Hisao

2015-01-01

In our previous study of 3-year-old children in a dioxin contamination hot spot in Vietnam, the high total dioxin toxic equivalent (TEQ-PCDDs/Fs)-exposed group during the perinatal period displayed lower Bayley III neurodevelopmental scores, whereas the high 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-exposed group displayed increased autistic traits. In autistic children, urinary amino acid profiles have revealed metabolic alterations in the amino acids that serve as neurotransmitters in the developing brain. Therefore, our present study aimed to investigate the use of alterations in urinary amino acid excretion as biomarkers of dioxin exposure-induced neurodevelopmental deficits in highly exposed 3-year-old children in Vietnam. A nested case-control study of urinary analyses was performed for 26 children who were selected from 111 3-year-old children whose perinatal dioxin exposure levels and neurodevelopmental status were examined in follow-up surveys conducted in a dioxin contaminated hot spot. We compared urinary amino acid levels between the following 4 groups: (1) a high TEQ-PCDDs/Fs and high TCDD-exposed group; (2) a high TEQ-PCDDs/Fs but low TCDD-exposed group; (3) a low TEQ-PCDDs/Fs exposed and poorly developed group; and (4) a low TEQ-PCDDs/Fs exposed and well-developed group. Urinary levels of histidine and tryptophan were significantly decreased in the high TEQ-PCDDs/Fs and high TCDD group, as well as in the high TEQ-PCDDs/Fs but low TCDD group, compared with the low TEQ-PCDDs/Fs and well-developed group. However, the ratio of histidine to glycine was significantly lower only in the high TEQ-PCDDs/Fs and high TCDD group. Furthermore, urinary histidine levels and the ratio of histidine to glycine were significantly correlated with neurodevelopmental scores, particularly for language and fine motor skills. These results indicate that urinary histidine is specifically associated with dioxin exposure-induced neurodevelopmental deficits, suggesting that urinary histidine may be a useful marker of dioxin-induced neurodevelopmental deficits and that histaminergic neurotransmission may be an important pathological contributor to dioxin-mediated neurotoxicity.

Determination of PCDD/Fs in breast milk of women living in the vicinities of Da Nang Agent Orange hot spot (Vietnam) and estimation of the infant's daily intake.

PubMed

Hue, N T M; Nam, V D; Thuong, N V; Huyen, N T; Phuong, N T H; Hung, N X; Tuan, N H; Son, L K; Minh, N H

2014-09-01

Seventeen toxic congeners of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in breast milks using the high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) method. Twenty seven breast milk samples were collected from primiparae who have lived over 5 years in wards namely Chinh Gian, An Khe, Khue Trung, and Hoa Thuan Tay which are located near the Da Nang Agent Orange hot spot (the AO/Dioxin hot spot). The samples were then analyzed for PCDD/F residues in order to assess the human exposure to dioxins from the AO/Dioxin hot spot, especially health risk to the breast-fed infants. The average TEQ levels in the four studied cohorts ranged from 8.1 to 26 pg/g lipid, with the highest level up to 51 pg TEQ/g lipid found in the An Khe ward. The TEQ level was correlated with geographical position and ranking in the order of Khue Trung, Hoa Thuan Tay, Chinh Gian and An Khe. The mean estimated PCDD/Fs infant's daily intake in the cohort of Khue Trung, Hoa Thuan Tay, Chinh Gian and An Khe was about 41, 122, 124, and 134 pg TEQ/kg bw/day, respectively, which are much higher than the tolerable daily intake proposed by the World Health Organization (4 pg TEQ/kg bw/day). Copyright © 2014 Elsevier B.V. All rights reserved.

Emission factors from aerial and ground measurements of field and laboratory forest burns in the southeastern US: PM2.5, black and brown carbon, VOC, and PCDD/PCDF.

PubMed

Aurell, Johanna; Gullett, Brian K

2013-08-06

Aerial- and ground-sampled emissions from three prescribed forest burns in the southeastern U.S. were compared to emissions from laboratory open burn tests using biomass from the same locations. A comprehensive array of emissions, including PM2.5, black carbon (BC), brown carbon (BrC), carbon dioxide (CO2), volatile organic compounds (VOCs), and polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were sampled using ground-based and aerostat-lofted platforms for determination of emission factors. The PM2.5 emission factors ranged from 14 to 47 g/kg biomass, up to three times higher than previously published studies. The biomass type was the primary determinant of PM2.5, rather than whether the emission sample was gathered from the laboratory or the field and from aerial- or ground-based sampling. The BC and BrC emission factors ranged from 1.2 to 2.1 g/kg biomass and 1.0 to 1.4 g/kg biomass, respectively. A decrease in BC and BrC emission factors with decreased combustion efficiency was found from both field and laboratory data. VOC emission factors increased with decreased combustion efficiency. No apparent differences in averaged emission factors were observed between the field and laboratory for BC, BrC, and VOCs. The average PCDD/PCDF emission factors ranged from 0.06 to 4.6 ng TEQ/kg biomass.

Journal Article: EPA's National Dioxin Air Monitoring Network ...

EPA Pesticide Factsheets

The U.S. Environmental Protection Agency (U.S. EPA) established the National Dioxin Air Monitoring Network (NDAMN) in June of 1998, and operated it until November of 2004. The objective of NDAMN was to determine background air concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dl-PCBs). NDAMN started with 10 sampling sites, adding more over time until the final count of 34 sites was reached by the beginning of 2003. Samples were taken quarterly, and the final sample count was 685. All samples were measured for 17 PCDD/PCDF congeners, 8 PCDD/PCDF homologue groups, and 7 dl-PCBs (note: 5 additional dl-PCBs were added for samples starting in the summer of 2002; 317 samples had measurements of 12 dl-PCBs). The overall average total toxic equivalent (TEQ) concentration in the United States was 11.2 fg TEQ m−3 with dl-PCBs contributing 0.8 fg TEQ m−3 (7%) to this total. The archetype dioxin and furan background air congener profile was seen in the survey averages and in most individual samples. This archetype profile is characterized by low and similar concentrations for tetra – through hexa PCDD/PCDF congeners, with elevations in four congeners – a hepta dioxin and furan congener, and both octa congeners. Sites were generally categorized as urban (4 sites), rural (23 sites), or remote (7 sites). The average TEQ concentrations over all sites and samples within these cat

Osprey distribution, abundance, reproductive success and contaminant burdens along lower Columbia River, 1997/1998 versus 2004

USGS Publications Warehouse

Henny, C.J.; Grove, R.A.; Kaiser, J.L.

2008-01-01

The osprey (Pandion haliaetus) population nesting along the lower portion of the Columbia River (river mile 29 to 286) increased from 94 in 1997 to 103 occupied nests in 1998 (9.6% annual rate of increase) to 225 occupied nests in 2004 (13.9% annual rate of increase). The more recent rate of population increase was associated with higher reproductive rates than in 1997/1998, and significantly lower egg concentrations of most organochlorine (OC) pesticides, polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). A comparison of observed egg residue concentrations in 2004 with effect-level information for ospreys indicated that reproduction at few, if any, nests was adversely affected. As recent as 1997/1998, dichlorodiphenyldichloroethylene (DDE) was still adversely affecting reproductive success for a portion of this population. Mercury was the only contaminant evaluated in both 1997/1998 and 2004 that showed a significant increase in eggs over time, but concentrations in 2004 (0.09 ??g g -1 ww) remained below established effect levels for birds (generally reported at 0.50 ??g g-1 ww or higher). The significant increase in mercury justifies the need for future monitoring. All contaminants mentioned that biomagnify up food chains can be effectively monitored in osprey eggs. The osprey has been shown to be an excellent sentinel species for long-term monitoring with their many useful traits described. ?? 2007 Springer Science+Business Media, LLC.

Dioxins from medical waste incineration: Normal operation and transient conditions.

PubMed

Chen, Tong; Zhan, Ming-xiu; Yan, Mi; Fu, Jian-ying; Lu, Sheng-yong; Li, Xiao-dong; Yan, Jian-hua; Buekens, Alfons

2015-07-01

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are key pollutants in waste incineration. At present, incinerator managers and official supervisors focus only on emissions evolving during steady-state operation. Yet, these emissions may considerably be raised during periods of poor combustion, plant shutdown, and especially when starting-up from cold. Until now there were no data on transient emissions from medical (or hospital) waste incineration (MWI). However, MWI is reputed to engender higher emissions than those from municipal solid waste incineration (MSWI). The emission levels in this study recorded for shutdown and start-up, however, were significantly higher: 483 ± 184 ng Nm(-3) (1.47 ± 0.17 ng I-TEQ Nm(-3)) for shutdown and 735 ng Nm(-3) (7.73 ng I-TEQ Nm(-3)) for start-up conditions, respectively. Thus, the average (I-TEQ) concentration during shutdown is 2.6 (3.8) times higher than the average concentration during normal operation, and the average (I-TEQ) concentration during start-up is 4.0 (almost 20) times higher. So monitoring should cover the entire incineration cycle, including start-up, operation and shutdown, rather than optimised operation only. This suggestion is important for medical waste incinerators, as these facilities frequently start up and shut down, because of their small size, or of lacking waste supply. Forthcoming operation should shift towards much longer operating cycles, i.e., a single weekly start-up and shutdown. © The Author(s) 2015.

State of the art and advances in the impact assessment of dioxins and dioxin-like compounds.

PubMed

Schiavon, Marco; Torretta, Vincenzo; Rada, Elena Cristina; Ragazzi, Marco

2016-01-01

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) are toxic and persistent organic pollutants that are able to enter the food chain, accumulate in the fat tissues of animals, and consequently pose a serious risk for human health. Consolidated tools for exposure assessment have been implemented during the last decades and widely used, both in the environmental monitoring and in modeling activities. Although the emissive trend and the concentrations in the environment have gradually decreased during the last 20 years, some situations are still underrated and not adequately controlled by the environmental legislation. On the other hand, a complete monitoring of all the pathways of exposure to PCDD/Fs and PCBs is technically and economically unfeasible. Therefore, this paper aims at providing an overview of the traditional approaches used to assess the impacts of PCDD/Fs and PCBs and presenting the novelties introduced during the last years. After an initial characterization of their toxicity and their effects on health, this paper focuses on activities and situations that can result in critical releases of PCDD/Fs and PCBs into the atmosphere and that can represent a hidden threat for the population. In the final part, this study presents the current methodologies for exposure assessment, summarizes the food chain models in a unified way, and puts the light on new methods that can help environmental scientists, risk assessors, and decision makers to estimate the risk related to exposure to PCDD/Fs in different contexts.

Emissions from open burning of used agricultural pesticide containers.

PubMed

Gullett, Brian K; Tabor, Dennis; Touati, Abderrahmane; Kasai, Jeanne; Fitz, Nancy

2012-06-30

Emissions from simulated open burning of used agricultural pesticide containers were sampled for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/PCDFs), polycyclic aromatic hydrocarbon compounds (PAHs), and particle matter (PM(10) and PM(2.5)). Clean high density polyethylene (HDPE) containers, containers with trace pesticide, and triple-rinsed containers were burned separately in an open combustion facility and their emissions compared. Two common chlorinated pesticides were used: 2,4-dichlorophenoxyacetic acid (2,4-D) and 1-chloro-3-ethylamino-5-isopropylamino-2,4,6-triazine (atrazine). PCDD/PCDF emission factors ranged from 0.1 to 24ng toxic equivalents (TEQ)/kg C burned with a mean and median of 4.9 and 1.9ng TEQ/kgC burned, respectively. In a limited number of trials, the trace 2,4-D in the HDPE container led to a statistically significant increase in PCDD/PCDF formation compare to all other conditions. Residual atrazine did not lead to more PCDD/PCDF than the unrinsed 2,4-D container. Total (16 compounds) PAH emission factors varied from 1.5 to 6.7mg/kgC burned. These limited data suggest that rinsing the 2,4-D container prior to burning reduces both PCDD/PCDF and PAH emissions. Nine PM(2.5) emission factors ranged from 9 to 35mg/gC burned and ten PM(10) values ranged from 6 to 43mg/gC burned. Neither pesticide appeared to have any effect on PM concentration. Published by Elsevier B.V.

Assessment on dioxin-like compounds intake from various marine fish from Zhoushan Fishery, China.

PubMed

Wang, Xiangyong; Zhang, Hongxia; Zhang, Lei; Zhong, Kai; Shang, Xiaohong; Zhao, Yunfeng; Tong, Zhendong; Yu, Xinwei; Li, Jingguang; Wu, Yongning

2015-01-01

Sea fish consuming is an important intake source of dioxin-like compounds, especially for the coastal residents. To assess the intake levels of these contaminants from sea fish and to provide risk-based consumption advice, concentrations of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) were measured in 32 commonly consumed fish species from Zhoushan Fishery, China. Due to the different accumulation influenced by fat content, feed habits and living zone in the sea area, the levels of PCDDs, PCDFs and dl-PCBs in different fish species varied significantly ranging from 0.002 to 0.078pg WHO-TEQ/g fresh weight, from 0.002 to 0.553pg WHO-TEQ/g fresh weight and from 0.003 to 2.059pg WHO-TEQ/g fresh weight, respectively. Based on mean fish consuming rate in China, the estimated maximum possible dioxin-like compounds intake through different fish species ranged from 0.26 to 65.61pgTEQkg(-1)bwmonth(-1). Bullet mackerel has the highest monthly intake level which was much higher than other fish species and very close to the provisional tolerable monthly intake (70pgTEQkg(-)(1)bwmonth(-)(1)) proposed by the Joint FAO/WHO Expert Committee on Food Additives. Hence, comparing to other fish species, the consumption of Bullet mackerel from Zhoushan Fishery should be cautious to reduce the potential health risk. Copyright © 2014 Elsevier Ltd. All rights reserved.

A sensitive, rapid, and simple DR-EcoScreen bioassay for the determination of PCDD/Fs and dioxin-like PCBs in environmental and food samples.

PubMed

Kojima, Hiroyuki; Takeuchi, Shinji; Iida, Mitsuru; Nakayama, Shoji F; Shiozaki, Takuya

2018-03-01

In developing countries in Asia, such as China, Vietnam, and Thailand, there is a strong need for the development of relatively rapid and low-cost bioassays for the determination of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs) in environmental and food samples. These compounds are known to induce a variety of toxic and biological effects through their ligand-specific binding of the aryl hydrocarbon receptor (AhR). Indeed, several AhR-mediated reporter gene assays are widely used as prescreening tools for high-resolution gas chromatography/high-resolution mass spectrometry (HRGC-HRMS) analysis, which individually measures 17 PCDD/Fs and 12 DL-PCBs. In 2008, we have developed a new sensitive and rapid reporter gene assay using a genetically engineered stable cell line, designated DR-EcoScreen cells. The DR-EcoScreen assay using these cells has a number of great advantages of its sensitivity to 2,3,7,8-tetrachlorodibenzo-p-dioxin and its simple procedure, which shows little variance in the data (within CV 10 %) compared to other reporter gene assays. In this review, we summarize the application of the DR-EcoScreen assay to the determination of PCDD/Fs and DL-PCBs in ambient air samples, in fish and shellfish samples, and in flue gas samples from incinerators and provide potential usefulness of this bioassay for the determination of PCDD/Fs and DL-PCBs in various matrices.

Contamination of food samples from Malaysia with polychlorinated dibenzo-p-dioxins and dibenzofurans and estimation of human intake.

PubMed

Leong, Yin-Hui; Chiang, Pui-Nyuk; Jaafar, Hajjaj Juharullah; Gan, Chee-Yuen; Majid, Mohamed Isa Abdul

2014-04-01

A total of 126 food samples, categorised into three groups (seafood and seafood products, meat and meat products, as well as milk and dairy products) from Malaysia were analysed for polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The concentration of PCDD/Fs that ranged from 0.16 to 0.25 pg WHO05-TEQ g(-1) fw was found in these samples. According to the food consumption data from the Global Environment Monitoring System (GEMS) of the World Health Organization (WHO), the dietary exposures to PCDD/F from seafood and seafood products, meat and meat products, as well as milk and dairy products for the general population in Malaysia were 0.064, 0.183 and 0.736 pg WHO05-TEQ kg(-1) bw day(-1), respectively. However, the exposure was higher in seafood and seafood products (0.415 pg WHO05-TEQ kg(-1) bw day(-1)) and meat and meat products (0.317 pg WHO05-TEQ kg(-1) bw day(-1)) when the data were estimated using the Malaysian food consumption statistics. The lower exposure was observed in dairy products with an estimation of 0.365 pg WHO05-TEQ kg(-1) bw day(-1). Overall, these dietary exposure estimates were much lower than the tolerable daily intake (TDI) as recommended by WHO. Thus, it is suggested that the dietary exposure to PCDD/F does not represent a risk for human health in Malaysia.

Interplay of metals and bromine with dioxin-related compounds concentrated in e-waste open burning soil from Agbogbloshie in Accra, Ghana.

PubMed

Fujimori, Takashi; Itai, Takaaki; Goto, Akitoshi; Asante, Kwadwo A; Otsuka, Masanari; Takahashi, Shin; Tanabe, Shinsuke

2016-02-01

Open burning of electronic waste (e-waste) releases various metals and organohalogen compounds in the environment. Here we investigated the interplay of metals (Cu, Pb, Zn, Fe, Co, and Sr) and bromine (Br) in the formation of dioxin-related compounds (DRCs), including polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs), as well as non-regulated DRCs such as polybrominated dibenzo-p-dioxins/furans (PBDD/Fs) and their monobrominated PCDD/Fs in soils sampled from open burning e-waste sites at Agbogbloshie in Accra, Ghana. The predominant DRCs were PBDFs, PCDFs, PCDDs, and DL-PCBs. Statistical analyzes, X-ray absorption spectroscopy, and the PCDF/PCDD ratio suggested possible formation paths of PCDD/Fs and DL-PCBs by catalytic behaviors of copper chlorides (CuCl, CuCl2, and Cu2(OH)3Cl) and thermal breakdown of polyvinyl chloride. Predominant formation of brominated furans may be derived from electron transfer from intermediates of PBDE to copper, Cu(II) → Cu(I). Lead chloride also contributed to generate DRCs and may become highly bioaccessible through the open burning of e-waste. The main zinc species (ZnCl2 and ZnS) suggested a possible relationship to generate DRCs and specific zinc source such as tire burning. Cu, Pb, Zn, and Br contained in various e-wastes, wires/cables, plastics, and tires strongly influenced generation of many DRCs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dioxin equivalency: Challenge to dose extrapolation

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

Brown, J.F. Jr.; Silkworth, J.B.

1995-12-31

Extensive research has shown that all biological effects of dioxin-like agents are mediated via a single biochemical target, the Ah receptor (AhR), and that the relative biologic potencies of such agents in any given system, coupled with their exposure levels, may be described in terms of toxic equivalents (TEQ). It has also shown that the TEQ sources include not only chlorinated species such as the dioxins (PCDDs), PCDFs, and coplanar PCBs, but also non-chlorinated substances such as the PAHs of wood smoke, the AhR agonists of cooked meat, and the indolocarbazol (ICZ) derived from cruciferous vegetables. Humans have probably hadmore » elevated exposures to these non-chlorinated TEQ sources ever since the discoveries of fire, cooking, and the culinary use of Brassica spp. Recent assays of CYP1A2 induction show that these ``natural`` or ``traditional`` AhR agonists are contributing 50--100 times as much to average human TEQ exposures as do the chlorinated xenobiotics. Currently, the safe doses of the xenobiotic TEQ sources are estimated from their NOAELs and large extrapolation factors, derived from arbitrary mathematical models, whereas the NOAELs themselves are regarded as the safe doses for the TEQs of traditional dietary components. Available scientific data can neither support nor refute either approach to assessing the health risk of an individual chemical substance. However, if two substances be toxicologically equivalent, then their TEQ-adjusted health risks must also be equivalent, and the same dose extrapolation procedure should be used for both.« less

Effect of MSW source-classified collection on the emission of PCDDs/Fs and heavy metals from incineration in China.

PubMed

Shi, De-Zhi; Wu, Wei-Xiang; Lu, Sheng-Yong; Chen, Tong; Huang, Hui-Liang; Chen, Ying-Xu; Yan, Jian-Hua

2008-05-01

Municipal solid waste (MSW) source-classified collection represents a change in MSW management in China and other developing countries. Comparative experiments were performed to evaluate the effect of a newly established MSW source-classified collection system on the emission of PCDDs/Fs (polychlorinated dibenzo-p-dioxins and dibenzofurans) and heavy metals (HMs) from a full-scale incinerator in China. As a result of presorting and dewatering, the chlorine level, heavy metal and water content were lower, but heat value was higher in the source-classified MSW (classified MSW) as compared with the conventionally mixed collected MSW (mixed MSW). The generation of PCDDs/Fs in flue gas from the classified MSW incineration was 9.28 ng I-TEQ/Nm(3), only 69.4% of that from the mixed MSW incineration, and the final emission of PCDDs/Fs was only 0.12 ng I-TEQ/Nm(3), although activated carbon injection was reduced by 20%. The level of PCDDs/Fs in fly ash from the bag filter was 0.27 ng I-TEQ/g. These results indicated that the source-classified collection with pretreatment could improve the characteristics of MSW for incineration, and significantly decrease formation of PCDDs/Fs in MSW incineration. Furthermore, distributions of HMs such as Cd, Pb, Cu, Zn, Cr, As, Ni, Hg in bottom ash and fly ash were investigated to assess the need for treatment of residual ash.

DIOXIN FORMATION: THE BURN BARREL STUDY

EPA Science Inventory

The paper reports results from tests designed to examine some of the factors influencing the emissions of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) from burn barrels. Results from PCDDs/Fs and polychlorinated biphenyls (PCBs) are reported, al...

The OH-initiated atmospheric chemical reactions of polyfluorinated dibenzofurans and polychlorinated dibenzofurans: A comparative theoretical study.

PubMed

Zeng, Xiaolan; Chen, Jing; Qu, Ruijuan; Pan, Xiaoxue; Wang, Zunyao

2017-02-01

The atmospheric chemical reactions of some polyfluorinated dibenzofurans (PFDFs) and polychlorinated dibenzofurans (PCDFs), initiated by OH radical, were investigated by performing theoretical calculations using density functional theory (DFT) and B3LYP/6-311++G(2df,p) method. The obtained results indicate that OH addition reactions of PFDFs and PCDFs occurring at C 1∼4 and C A sites are thermodynamic spontaneous changes and the branching ratio of the PF(C)DF-OH adducts is decided primarily by kinetic factor. The OH addition reactions of PFDFs taking place at fluorinated C 1∼4 positions are kinetically comparable with those occurring at nonfluorinated C 1∼4 positions, while OH addition reactions of PCDFs occurring at chlorinated C 1∼4 sites are negligible. The total rate constants of the addition reactions of PFDFs or PCDFs become smaller with consecutive fluorination or chlorination, and substituting at C 1 position has more adverse effects than substitution at other sites. The succedent O 2 addition reactions of PF(C)DF-OH adducts are thermodynamic nonspontaneous processes under the atmospheric conditions, and have high Gibbs free energies of activation (Δ r G ≠ ). The substituted dibenzofuranols are the primary oxidation products for PCDFs under the atmospheric conditions. However, other oxidative products may also be available for PFDFs besides substituted dibenzofuranols. Copyright © 2016 Elsevier Ltd. All rights reserved.

Embryotoxicity of an extract from Great Lakes lake trout to rainbow trout and lake trout

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

Wright, P.J.; Tillitt, D.E.

1995-12-31

Aquatic ecosystems such as the Great Lakes are known to be contaminated with chemicals that are toxic to fish. However, the role of these contaminants in reproductive failures of fishes, such as lake trout recruitment, has remained controvertible. It was the objective to evaluate dioxin-like embryotoxicity of a complex mixture of chemicals and predict their potential to cause the lack of recruitment in Great Lakes lake trout. Graded doses of a complex environmental extract were injected into eggs of both rainbow trout and lake trout. The extract was obtained from whole adult lake trout collected from Lake Michigan in 1988.more » The extract was embryotoxic in rainbow trout, with LD50 values for Arlee strain and Erwin strain of 33 eggEQ and 14 eggEQ respectively. The LOAEL for hemorrhaging, yolk-sac edema, and craniofacial deformities in rainbow trout were 2, 2, and 4 eggEQ, respectively. Subsequent injections of the extract into lake trout eggs were likewise embryotoxic, with an LD50 value of 7 eggEQ. The LOAEL values for the extract in lake trout for hemorrhaging, yolk-sac edema, and craniofacial deformities were 0.1, 1, and 2 eggEQ, respectively. The current levels of contaminants in lake trout eggs are above the threshold for hemorrhaging and yolk-sac edema. The results also support the use of an additive model of toxicity to quantify PCDDs, PCDFs, Non-o-PCBs, and Mono-o-PCBs in relation to early life stage mortality in Lake Michigan lake trout.« less

Characterization of atmospheric emission sources in lichen from metal and organic contaminant patterns.

PubMed

Ratier, Aude; Dron, Julien; Revenko, Gautier; Austruy, Annabelle; Dauphin, Charles-Enzo; Chaspoul, Florence; Wafo, Emmanuel

2018-03-01

Lichen samples from contrasted environments, influenced by various anthropic activities, were investigated focusing on the contaminant signatures according to the atmospheric exposure typologies. Most of the contaminant concentrations measured in the 27 lichen samples, collected around the industrial harbor of Fos-sur-Mer (France), were moderate in rural and urban environments, and reached extreme levels in industrial areas and neighboring cities (Al up to 6567 mg kg -1 , Fe 42,398 mg kg -1 , or ΣPAH 1417 μg kg -1 for example). At the same time, a strong heterogeneity was noticed in industrial samples while urban and rural ones were relatively homogeneous. Several metals could be associated to steel industry (Fe, Mn, Cd), road traffic, and agriculture (Sb, Cu, Sn), or to a distinct chemical installation (Mo). As well, PCDFs dominated in industrial samples while PCDDs prevailed in urban areas. The particularities observed supported the purpose of this work and discriminated the contributions of various atmospheric pollution emission sources in lichen samples. A statistical approach based on principal component analysis (PCA) was applied and resolved these potential singularities into specific component factors. Even if a certain degree of mixing of the factors is pointed out, relevant relationships were observed with several atmospheric emission sources. By this methodology, the contribution of industrial emissions to the atmospheric metal, PAH, PCB, and PCDD/F levels was roughly estimated to be 60.2%, before biomass burning (10.2%) and road traffic (3.8%). These results demonstrate that lichen biomonitoring offers an encouraging perspective of spatially resolved source apportionment studies.

Elevated concentrations of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans and polybrominated diphenyl ethers in hair from workers at an electronic waste recycling facility in eastern China.

PubMed

Ma, Jing; Cheng, Jinping; Wang, Wenhua; Kunisue, Tatsuya; Wu, Minghong; Kannan, Kurunthachalam

2011-02-28

Hair samples collected from e-waste recycling workers (n=23 males, n=4 females) were analyzed to assess occupational exposures to polybrominated diphenyl ethers (PBDEs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) at a large e-waste recycling facility in Taizhou, eastern China. Hair samples from a reference population composed of residents of Shanghai (n=11) were analyzed for comparison. The mean concentration of ∑PBDEs (range, 22.8-1020 ng/g dw; mean, 157 ng/g dw) found in hair samples from e-waste recycling workers was approximately 3 times higher than the mean determined for the reference samples. The congener profiles of PBDEs in hair from e-waste recycling workers were dominated by BDE 209, whereas the profiles in the reference-population samples showed comparable levels of BDE 47 and BDE 209. Total PCDD/F concentrations in hair from e-waste workers (range, 126-5820 pg/g dw; mean, 1670 pg/g dw) were approximately 18-fold greater than the concentrations measured in hair from the reference population. Concentrations of PCDFs were greater than concentrations of PCDDs, in all of the hair samples analyzed (samples from e-waste and non-e-waste sites). Tetrachlorodibenzofurans (TCDFs) were the major homologues in hair samples. Overall, e-waste recycling workers had elevated concentrations of both PBDEs and PCDD/Fs, indicating that they are exposed to high levels of multiple persistent organic pollutants. Copyright © 2010 Elsevier B.V. All rights reserved.

Design and implementation of an air monitoring program in support of a brownfields redevelopment program

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

Maisel, B.E.; Hunt, G.T.; Devaney, R.J. Jr.

EPA`s Brownfields Economic Redevelopment Initiative has sparked renewal of industrial and commercial parcels otherwise idled or under-utilized because of real or perceived environmental contamination. In certain cases, restoring such parcels to productive economic use requires a redevelopment effort protective of human health and welfare through minimizing offsite migration of environmental contaminants during cleanup, demolition and remediation activities. To support these objectives, an air monitoring program is often required as an integral element of a comprehensive brownfields redevelopment effort. This paper presents a strategic framework for design and execution of an ambient air monitoring program in support of a brownfields remediationmore » effort ongoing in Lawrence, MA. Based on site characterization, the program included sample collection and laboratory analysis of ambient air samples for polychlorinated biphenyls (PCBs), polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/PCDFs), total suspended particulate (TSP), inhalable particulate (PM10), and lead. The program included four monitoring phases, identified as background, wintertime, demolition/remediation and post-demolition. Air sampling occurred over a 16 month period during 1996--97, during which time nine sampling locations were utilized to produce approximately 1,500 ambient air samples. Following strict data review and validation procedures, ambient air data interpretation focused on the following: evaluation of upwind/downwind sample pairs, comparison of ambient levels to existing regulatory standards, relation of ambient levels to data reported in the open literature, and, determination of normal seasonal variations in existing background burden, comparison of ambient levels measured during site activity to background levels.« less

An enzyme-linked immunosorbent assay for the determination of dioxins in contaminated sediment and soil samples

PubMed Central

Van Emon, Jeanette M.; Chuang, Jane C.; Lordo, Robert A.; Schrock, Mary E.; Nichkova, Mikaela; Gee, Shirley J.; Hammock, Bruce D.

2010-01-01

A 96-microwell enzyme-linked immunosorbent assay (ELISA) method was evaluated to determine PCDDs/PCDFs in sediment and soil samples from an EPA Superfund site. Samples were prepared and analyzed by both the ELISA and a gas chromatography/high resolution mass spectrometry (GC/HRMS) method. Comparable method precision, accuracy, and detection level (8 ng kg−1) were achieved by the ELISA method with respect to GC/HRMS. However, the extraction and cleanup method developed for the ELISA requires refinement for the soil type that yielded a waxy residue after sample processing. Four types of statistical analyses (Pearson correlation coefficient, paired t-test, nonparametric tests, and McNemar’s test of association) were performed to determine whether the two methods produced statistically different results. The log-transformed ELISA-derived 2,3,7,8-tetrachlorodibenzo-p-dioxin values and logtransformed GC/HRMS-derived TEQ values were significantly correlated (r = 0.79) at the 0.05 level. The median difference in values between ELISA and GC/HRMS was not significant at the 0.05 level. Low false negative and false positive rates (<10%) were observed for the ELISA when compared to the GC/HRMS at 1000 ng TEQ kg−1. The findings suggest that immunochemical technology could be a complementary monitoring tool for determining concentrations at the 1000 ng TEQ kg−1 action level for contaminated sediment and soil. The ELISA could also be used in an analytical triage approach to screen and rank samples prior to instrumental analysis. PMID:18313102

Case Report: Human Exposure to Dioxins from Clay

PubMed Central

Franzblau, Alfred; Hedgeman, Elizabeth; Chen, Qixuan; Lee, Shih-Yuan; Adriaens, Peter; Demond, Avery; Garabrant, David; Gillespie, Brenda; Hong, Biling; Jolliet, Olivier; Lepkowski, James; Luksemburg, William; Maier, Martha; Wenger, Yvan

2008-01-01

Context For the general population, the dominant source of exposure to dioxin-like compounds is food. As part of the University of Michigan Dioxin Exposure Study (UMDES), we measured selected polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) in serum of 946 subjects who were a representative sample of the general population in five Michigan counties. Case presentation The total toxic equivalency (TEQ; based on 2005 World Health Organization toxic equivalency factors) of serum from the index case was 211 ppt on a lipid-adjusted basis, which was the highest value observed in the UMDES study population. This subject had no apparent opportunity for exposure to dioxins, except that she had lived on property with soil contaminated with dioxins for almost 30 years, and had been a ceramics hobbyist for > 30 years. Soil from her property and clay that she used for ceramics were both contaminated with dioxins, but the congener patterns differed. Discussion The congener patterns in this subject’s serum, soil, and ceramic clay suggest strongly that the dioxin contamination in clay and not soil was the dominant source of dioxin contamination in her serum. Relevance to public health practice: It appears that ceramic clay, in particular the process of firing clay with unvented kilns, can be a significant nonfood and nonindustrial source of human exposure to dioxins among ceramics hobbyists. The extent of human exposure from ceramic clay is unclear, but it may be widespread. Further work is needed to more precisely characterize the routes of exposure. PMID:18288324

Accumulation of environmental contaminants in wood duck (Aix sponsa) eggs, with emphasis on polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans

USGS Publications Warehouse

Augspurger, T.P.; Echols, K.R.; Peterman, P.H.; May, T.W.; Orazio, C.E.; Tillitt, D.E.; Di Giulio, R.T.

2008-01-01

We measured polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), organochlorine pesticides, and mercury in wood duck (Aix sponsa) eggs collected near a North Carolina (USA) bleached kraft paper mill. Samples were taken a decade after the mill stopped using molecular chlorine. Using avian toxic equivalency factors, 2,3,7,8-tetrachlorodibenzo-p-dioxin toxicity equivalent (TEQ) concentrations were 1-30 pg/g fresh wet weight in eggs (n = 48) collected near the mill in 2002-2005 and were significantly higher than those from a reference site (<1 pg/g) 25 km away. Geometric mean wood duck egg TEQs (6 pg/g) were one-fifth those measured at this site prior to the cessation of molecular chlorine bleaching. Concentrations of mercury in wood duck eggs from nests of the Roanoke River sites ranged from 0.01 to 0.14 ??g/g (geometric mean, 0.04 ??g/g) and were significantly higher than those from the reference site, where concentrations did not exceed 0.04 ??g/g (geometric mean, 0.02 ??g/g). All concentrations were lower than those associated with adverse effects in birds. The congener profiles, lack of contamination in reference site eggs, and decline in contaminant concentrations after process changes at the mill provide strong evidence that mill discharges influenced contamination of local wood duck eggs. Collectively, the results indicate that the wood duck is an effective sentinel of the spatial and temporal extent of PCDD, PCDF, and mercury contamination. ?? 2008 US Government.

Dietary exposure and risk assessment of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like polychlorinated biphenyls of the population in the Region of Valencia (Spain).

PubMed

Quijano, Leyre; Marín, Silvia; Millan, Encarnación; Yusà, Vicent; Font, Guillermina; Pardo, Olga

2018-04-01

Dietary exposure of the Valencia Region population to polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and PCBs was assessed in the Region of Valencia in 2010-2011. A total of 7700 food samples were collected. Occurrence data were combined with consumption data to estimate dietary exposure in adults (>15 years of age) and young people (6-15 years of age). The estimated intake was calculated by a probabilistic approach. Average intake levels (upper-bound scenario) were 1.58 and 2.76 pg toxic equivalent (TEQ) kg -1 body weight (bw) day -1 for adults and young people, respectively. These average intakes are within range of the tolerable daily intake of 1-4 pg WHO-TEQ kg -1 bw day -1 recommended by WHO, and slightly above the tolerable weekly intake (TWI) of 14 pg TEQ kg -1 bw week -1 and the Provisional tolerable monthly intake of 70 pg TEQ kg -1 bw month -1 set by the Scientific Committee on Food and the Joint FAO/WHO Expert Committee on Food, respectively. These results show that the contamination levels in food and therefore the exposure of the general population to PCDD/Fs and PCBs have declined in this region and therefore show the efficiency of the European risk-management measures. In terms of risk characterisation, the results showed that, under the upper-bound scenario, 22% of the adult and 58% of the young people population could exceed the TWI.

Dietary exposure to dioxins and dioxin-like PCBs of Hong Kong adults: results of the first Hong Kong Total Diet Study.

PubMed

Wong, Waiky W K; Yip, Yiu-chung; Choi, Koon-kay; Ho, Y Y; Xiao, Ying

2013-01-01

Dioxins and dioxin-like polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) covered by the Stockholm Convention on POPs. To assess the associated health risk of the Hong Kong population, the dietary exposure of the Hong Kong population and various age-gender subgroups to dioxins and dioxin-like PCBs was estimated in the first Hong Kong Total Diet Study (TDS), where food samples were collected and prepared "as consumed". A total of 142 composite food samples, mainly foods of animal origin and their products and oily food, were analysed for polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and dioxin-like PCBs by the high-resolution gas chromatograph/high-resolution mass spectrometer (HRGC/HRMS) system. Dietary exposures were estimated by combining the analytical results with the food consumption data of Hong Kong adults. The mean and 95th percentile exposures to dioxins and dioxin-like PCBs of the Hong Kong population were 21.9 and 59.7 pg toxic equivalent (TEQ) kg⁻¹ body weight (bw) month⁻¹ respectively, which amounted to 31.3% and 85.2% of the provisional tolerable monthly intake (PTMI). The main dietary source of dioxins and dioxin-like PCBs was "Fish and seafood and their products" (61.9% of the total exposure), followed by "Meat, poultry and game and their products" (20.0%) and "Mixed dishes" (6.95%). The study findings suggest that the Hong Kong population is unlikely to experience the major undesirable health effects of dioxins and dioxin-like PCBs.

Decreased PCDD/F formation when co-firing a waste fuel and biomass in a CFB boiler by addition of sulphates or municipal sewage sludge.

PubMed

Åmand, Lars-Erik; Kassman, Håkan

2013-08-01

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustion temperatures (<700 °C), incineration of electronic waste and plastic waste containing chlorine are all factors influencing the formation of PCDD/Fs in boilers. The impact of chlorine and catalysing metals (such as copper and iron) in the fuel on PCDD/F formation was studied in a 12 MW(th) circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS as additional fuel. Copyright © 2013 Elsevier Ltd. All rights reserved.

Estimating persistence of brominated and chlorinated organic pollutants in air, water, soil, and sediments with the QSPR-based classification scheme.

PubMed

Puzyn, T; Haranczyk, M; Suzuki, N; Sakurai, T

2011-02-01

We have estimated degradation half-lives of both brominated and chlorinated dibenzo-p-dioxins (PBDDs and PCDDs), furans (PBDFs and PCDFs), biphenyls (PBBs and PCBs), naphthalenes (PBNs and PCNs), diphenyl ethers (PBDEs and PCDEs) as well as selected unsubstituted polycyclic aromatic hydrocarbons (PAHs) in air, surface water, surface soil, and sediments (in total of 1,431 compounds in four compartments). Next, we compared the persistence between chloro- (relatively well-studied) and bromo- (less studied) analogs. The predictions have been performed based on the quantitative structure-property relationship (QSPR) scheme with use of k-nearest neighbors (kNN) classifier and the semi-quantitative system of persistence classes. The classification models utilized principal components derived from the principal component analysis of a set of 24 constitutional and quantum mechanical descriptors as input variables. Accuracies of classification (based on an external validation) were 86, 85, 87, and 75% for air, surface water, surface soil, and sediments, respectively. The persistence of all chlorinated species increased with increasing halogenation degree. In the case of brominated organic pollutants (Br-OPs), the trend was the same for air and sediments. However, we noticed that the opposite trend for persistence in surface water and soil. The results suggest that, due to high photoreactivity of C-Br chemical bonds, photolytic processes occurring in surface water and soil are able to play significant role in transforming and removing Br-OPs from these compartments. This contribution is the first attempt of classifying together Br-OPs and Cl-OPs according to their persistence, in particular, environmental compartments.

Survey of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and non-ortho-polychlorinated biphenyls in US meat and poultry, 2012-13: toxic equivalency levels, patterns, temporal trends and implications.

PubMed

Lupton, Sara J; O'Keefe, Margaret; Muñiz-Ortiz, Jorge G; Clinch, Nelson; Basu, Pat

2017-11-01

The US Department of Agriculture (USDA) conducts a statistically based survey of the domestic meat supply (beef, pork, chicken and turkey) to determine current levels of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and non-ortho-polychlorinated biphenyls (no-PCBs) every 5 years. Fat samples for each slaughter class were collected from US federally licensed slaughter facilities. The samples were processed and analysed for 17 PCDD/Fs and three no-PCBs. The sum of PCDD, PCDF and no-PCB toxic equivalencies (sum-TEQ) calculated using 2005 toxic-equivalency factors for all slaughter classes ranged from non-detect (n.d.) to 6.47 pg TEQ g -1 lipid. The median sum-TEQs, when n.d. = 0.5 LOD, for beef, pork, chicken and turkey were 0.66, 0.12, 0.13 and 0.34 pg TEQ g -1 lipid respectively. A comparison of the current survey with the previous three surveys shows a declining trend, with decreasing differences between medians; differences between the median sum-TEQs from 2007-08 and 2012-13 were -10%, -29%, -33% and -25% for beef, pork, chicken and turkey respectively. Several beef samples underwent further characterisation and congener patterns from these beef samples suggested pentachlorophenol treated wood as the likely exposure source. US consumer exposure to these compounds is relatively low and no slaughter class contributed more than 26% to the US Environmental Protection Agency (USEPA) chronic oral reference dose of 0.7 pg TEQ kg -1 bw day -1 .

Emissions of toxic pollutants from co-combustion of demolition and construction wood and household waste fuel blends.

PubMed

Edo, Mar; Ortuño, Núria; Persson, Per-Erik; Conesa, Juan A; Jansson, Stina

2018-07-01

Four different types of fuel blends containing demolition and construction wood and household waste were combusted in a small-scale experimental set-up to study the effect of fuel composition on the emissions of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), chlorobenzenes (PCBzs), chlorophenols (PCPhs) and polycyclic aromatic hydrocarbons (PAHs). Two woody materials, commercial stemwood (ST) and demolition and construction wood (DC) were selected because of the differences in their persistent organic pollutants (POPs), ash and metals content. For household waste, we used a municipal solid waste (MSW) and a refuse-derived fuel (RDF) from MSW with 5-20 wt% and up to 5 wt% food waste content respectively. No clear effect on the formation of pollutants was observed with different food waste content in the fuel blends tested. Combustion of ST-based fuels was very inefficient which led to high PAH emissions (32 ± 3.8 mg/kg fuel ). The use of DC clearly increased the total PCDD and PCDF emissions (71 ± 26 μg/kg fuel ) and had a clear effect on the formation of toxic congeners (210 ± 87 ng WHO 2005 -TEQ/kg fuel ). The high PCDD and PCDF emissions from DC-based fuels can be attributed to the presence of material contaminants such as small pieces of metals or plastics as well as timber treated with chromated copper arsenate preservatives and pentachlorophenol in the DC source. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

Ikonomou, M.G.; Crewe, N.F.; Fischer, M.

It has been demonstrated that marine mammals accumulate high concentrations of lipophilic organochlorine contaminants in blubber. As predators of the high trophic level they have also been used to evaluate contamination in the marine environment. Sampling of living marine mammals using a microsample (100 to 200 mg) biopsy dart technique offers a potentially invaluable chronicle in assessing levels and types of persistent environmental pollutants from a sample in which age, sex and other genetic information can additionally be ascertained. The authors have explored analytical methodology based on a high sensitivity detection system (HRGC/HRMS) which provides multi-residue determinations from biopsy dartmore » microsamples. Lipid content and the concentrations of PCDDs, PCDFs and non-ortho and mono-ortho substituted PCBs were measured in 100 mg biopsy dart replicates taken from a killer whale carcass and in three strata of the blubber of that carcass. Statistically acceptable results were obtained from the dart replicates which compared very well with those of the blubber strata. Analytical data from 100 mg extractions from an established in house blubber CRM also compared well against a series of 2.5 g extractions of that CRM. The extraction and cleanup procedures used also allow for the determination of other organohalogen contaminants such as DDT and other pesticides, all the remaining PCBs, polychlorinated diphenylethers and brominated residues. The strengths and limitations of the analytical methodology and the biopsy dart as a sampling tool and pollution predicator will be illustrated in terms of method accuracy and precision, glassware and procedural blanks associated with each extraction batch, and the incorporation of an in house micro reference standard.« less

GAS- AND SOLID-PHASE PARTITIONING OF PCDDS/FS ON MSWI FLY ASH AND THE EFFECTS OF SAMPLING

EPA Science Inventory

Semi-volatile organic compounds (SOCs), including polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDDs/Fs), are partitioned as gas-phase and particle-bound products of many industrial combustion processes. This gas/particle partitioning of SOCs has severe implications on both ...

THE USE OF SURROGATE COMPOUNDS AS INDICATORS OF PCDD/F CONCENTRATIONS IN COMBUSTOR STACK GASES

EPA Science Inventory

Emissions of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) from stationary combustion sources are of concern because they are carcinogenic and may result in disruption of endocrine systems in human and wildlife populations. PCDDs/Fs are typically ...

VARIABLES AFFECTING EMISSIONS OF PCDDS/FS FROM UNCONTROLLED COMBUSTION OF HOUSEHOLD WASTE IN BARRELS

EPA Science Inventory

The uncontrolled burning of household waste in barrels has recently been implicated as a major source of airborne emissions of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs). Based on the need to generate a more accurate emission factor for burn ba...

PARAMETERS INFLUENCING EMISSIONS OF PCDDS/FS FROM OPEN BURNING OF HOUSEHOLD WASTE IN BARRELS

EPA Science Inventory

The paper reports results from tests that were designed to examine some of the factors influencing the emissions of polychlorinated-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) from burn barrels. Based on the wide variability of emissions within duplicate-run sets, in ...

INVESTIGATION OF THE PATHWAYS TO PCDDS/FS FROM AN ETHYLENE DIFFUSION FLAME: FORMATION FROM SOOT AND AROMATICS

EPA Science Inventory

The formation of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) has been shown to occur from the combustion products of fuels as complex as municipal solid waste and as relatively simple as a methane flame. PCDD/F emissions from flame carbon in th...

Dioxins in cigarette smoke

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

Muto, H.; Takizawa, Y.

Dioxins in cigarettes, smoke, and ash were determined using gas chromatography/mass spectrometry. The total concentration of polychlorinated dibenzo-p-dioxins (PCDDs) in cigarette smoke was approximately 5.0 micrograms/m3 at the maximum level, whereas various congeners from tetra-octa-chlorodibenzo-p-dioxin (-CDD) were detected. Particullary, the total concentration of hepta-CDD congeners was the highest among these congeners. Mass fragmentograms of various PCDD congeners were similar to those in flue gas samples collected from a municipal waste incinerator. The PCDD congeners that were not present in the cigarettes were found in the smoke samples. The 2,3,7,8-TCDD toxic equivalent value--an index for effects on humans--for total PCDDs inmore » smoke was 1.81 ng/m3 using the toxic factor of the United States Environment Protection Agency. Daily intake of PCDDs by smoking 20 cigarettes was estimated to be approximately 4.3 pg.kg body weight/day. This value was close to that of the ADIs: 1-5 pg.kg body weight/day reported in several countries. A heretofore unrecognized health risk was represented by the presence of PCDDs in cigarette smoke.« less

Destruction kinetic of PCDDs/Fs in MSWI fly ash using microwave peroxide oxidation.

PubMed

Chang, Yu-Min; Fang, Wen-Bin; Tsai, Kuo-Sheng; Kao, Jimmy C M; Lin, Kae-Long; Chen, Ching-Ho

2015-01-01

Microwave peroxide oxidation is a less greenhouse gas emission and energy-efficient technology to destroy toxic organic compounds in hazardous waste. The research novelty is to adopt the innovative microwave peroxide oxidation in H2SO4/HNO3 solution to efficiently destroy the polychlorinated dibenzo-p-dioxins (PCDDs)/Fs in municipal solid waste incineration fly ash. The major objective of this paper is to study dynamic destruction of PCDDs/Fs using the microwave peroxide oxidation. Almost all PCDDs/Fs in the raw fly ash can be destructed in 120 min at a temperature of 423 K using the microwave peroxide oxidation treatment. It was found that the microwave peroxide oxidation provides the potential to destruct the PCDDs/Fs content in municipal solid waste incinerator (MSWI) fly ash to a low level as a function of treatment time. A useful kinetic correlation between destruction efficiency and treatment conditions is proposed on the basis of the experimental data obtained in this study. The significance of this work in terms of practical engineering applications is that the necessary minimum treatment time can be solved using a proposed graphic illustration method, by which the minimum treatment time is obtained if the desired destruction efficiency and treatment temperature are known. Because of inorganic salt dissolution, the temperature would be a critical factor facilitating the parts of fly ash dissolution. Material loss problem caused by the microwave peroxide oxidation and the effects of treatment time and temperature are also discussed in this paper.

Illegal Dumping of Toxic Waste and Its Effect on Human Health in Campania, Italy

PubMed Central

Mazza, Alfredo; Piscitelli, Prisco; Neglia, Cosimo; Rosa, Giulia Della; Iannuzzi, Leopoldo

2015-01-01

The region of Campania (particularly Naples and Caserta) has experienced an emergency in the waste management cycle during past years. Although the most critical phase has been overcome after the construction of the incineration plant in Acerra (an old-fashioned technology built up over a few months, whose impact on environment and health has not yet been assessed), most of the underlying problems have not been resolved. The illegal burning of wheels, plastics, textiles, and other industrial residuals, along with the detection of two thousand toxic substance dumping sites, still represents major concerns of environmental pollution and population health. This review summarizes the most relevant studies, which analyzed chemical contamination (primarily dioxins and polychlorinated biphenyls (PCBs)) of the air, soil, water, animals, and humans in Campania. In addition, we reviewed information on population health (i.e., mortality data, congenital malformations, and cancer incidence). Moving from a detailed mapping of (mostly illegal) waste dumping sites in Campania, we have focused on recent studies which have found: (a) high concentrations of dioxins (≥5.0 pg TEQ/g fat) in milk samples from sheep, cows, and river buffaloes; (b) remarkable contamination of dioxin and PCBs in human milk samples from those living in the Naples and Caserta areas (PCDDs+PCDFs and dioxin-like-PCBs (dl-PCBs) assessed at 16.6 pg TEQ/g of fat; range: 7.5–43 pg/g of fat); (c) potential age-adjusted standardized mortality rates associated with some specific cancer types; (d) a statistically significant association between exposure to illegal toxic waste dumping sites and cancer mortality, even after adjustment by socio-economic factors and other environmental indicators. PMID:26086704

PCDD/F and PCB in human serum of differently exposed population groups of an Italian city.

PubMed

Turrio-Baldassarri, Luigi; Abate, Vittorio; Battistelli, Chiara Laura; Carasi, Sergio; Casella, Marialuisa; Iacovella, Nicola; Indelicato, Annamaria; La Rocca, Cinzia; Scarcella, Carmelo; Alivernini, Silvia

2008-08-01

A chemical plant located in Brescia, an industrial city in North-Western Italy, produced polychlorobiphenyls (PCBs) during a 30-50 year period, causing widespread pollution of the surrounding agricultural area. This area contains several small farms, which principally produce veal meat for private consumption of the farmers' families. The pollution went undiscovered for many years, during which period contaminated food was regularly consumed. This paper reports the polychlorodibenzodioxin (PCDD), polychlorodibenzofuran (PCDF) and PCB levels of a serum sample pooled from the consumers of contaminated food, compared to six population groups of the city of Brescia. Four of these groups were selected in order to represent, respectively, the local general population and the residents of three zones of the polluted area, while the last two groups represented, respectively, the present and the former workers of the plant. One human milk sample from one of the consumers of contaminated food was also analyzed. Results show that the consumers of the contaminated food and the former workers of the plant display considerably higher levels than all other groups. The levels of general population and of all other groups were generally similar both to each other and to the range of literature values for unexposed populations. The respective contribution of PCDDs, PCDFs, mono-ortho and non-ortho PCBs (dioxin-like PCBs) to (Toxicity Equivalents) TEQ of the population groups of this study were also compared to literature data: the two groups with a high contamination level, together with the human milk sample, displayed a higher incidence of mono-ortho PCBs and a lower contribution of PCDD, possibly correlated with the source of contamination.

Integrated assessment of contaminated sediments in the lower Fox River and Green Bay, Wisconsin

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

Ankley, G.T.; Lodge, K.; Call, D.J.

Samples of sediment and biota were collected from sites in the lower Fox River and southern Green Bay to determine existing or potential impacts of sediment-associated contaminants on different ecosystem components of this Great Lakes area of concern. Evaluation of benthos revealed a relatively depauperate community, particularly at the lower Fox River sites. Sediment pore water and bulk sediments from several lower Fox River sites were toxic to a number of test species including Pimephales promelas, Ceriodaphnia dubia, Hexagenia limbata, Selenastrum capricornutum, and Photobacterium phosphorum. An important component of the observed toxicity appeared to be due to ammonia. Evaluation ofmore » three bullhead (Ictalurus) species from the lower Fox River revealed an absence of preneoplastic or neoplastic liver lesions, and the Salmonella typhimurium bioassay indicated relatively little mutagenicity in sediment extracts. Apparent adverse reproductive effects were noted in two species of birds nesting along the lower Fox River and on a confined disposal facility for sediments near the mouth of the river, and there were measurable concentrations of potentially toxic 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), and planar polychlorinated biphenyls (PCBs) both in the birds and in sediments from several of the study sites. Based on toxic equivalency factors and the results of an in vitro bioassay with H4IIE rat hepatoma cells, it appeared that the majority of potential toxicity of the PCB/PCDF/PCDD mixture in biota from the lower Fox River/Green Bay system was due to the planar PCBs. The results of these studies are discussed in terms of an integrated assessment focused on providing data for remedial action planning.« less

Uptake of planar polychlorinated biphenyls and 2,3,7,8-substituted polychlorinated dibenzofurans and dibenzo-p-dioxins by birds nesting in the lower Fox River and Green Bay, Wisconsin, USA

USGS Publications Warehouse

Ankley, Gerald T.; Niemi, Gerald J.; Lodge, Keith B.; Harris, Hallett J.; Beaver, Donald L.; Tillitt, Donald E.; Schwartz, Ted R.; Giesy, John P.; Jones, Paul D.; Hagley, Cynthia

1993-01-01

The uptake of persistent polychlorinated hydrocarbons (PCHs) by four avian species was investigated at upper trophic levels of two aquatic food chains of the lower Fox River and Green Bay, Wisconsin. Accumulation of total and specific planar polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans (PCDFs), polychlorinated dibenzo-p-dioxin (PCDDs), and H411E rat hepatoma cell bioassay-derived 2,37,8-tetrachlorodibenzop-dioxin equivalents (TCDD-EQ) was evaluated in Forster's tern (Sterna forsteri) and common tern (Sterna hirundo) chicks, and in tree swallow (Tachycineta bicolor) and red-winged blackbird (Agelaius phoeniceus) nestlings from colonies nesting in several locations within the watershed. Concentrations of the PCHs were greatest in eggs and chicks of the two tern species, less in the tree swallows and least in the red-winged blackbirds. Young of all four species accumulated total PCBs, PCB congeners 77, 105, 126, and 169, and TCDD-EQ. The young birds also accumulated small concentrations of several 2,3,7,8-sbustituted PCDF and PCDD congeners. Uptake rates for certain of the PCHs for the Forster's tern chicks were: 15 μg/day for total PCBs, 70, 200, 6.5, and 0.14 ng/day for PCB congeners 77, 105, 126, and 169, respectively, and 270 μg/day for TCDD-EQ. Principal components analysis revealed that the patterns of PCH concentrations in the samples were influenced by species of bird, their age (or length of exposure) and nesting location. Collectively, our findings demonstrate that exposure of avian species to contaminants derived from aquatic food chains can be characterized and quantified for the purposes of ecological risk assessment.

Illegal Dumping of Toxic Waste and Its Effect on Human Health in Campania, Italy.

PubMed

Mazza, Alfredo; Piscitelli, Prisco; Neglia, Cosimo; Della Rosa, Giulia; Iannuzzi, Leopoldo

2015-06-16

The region of Campania (particularly Naples and Caserta) has experienced an emergency in the waste management cycle during past years. Although the most critical phase has been overcome after the construction of the incineration plant in Acerra (an old-fashioned technology built up over a few months, whose impact on environment and health has not yet been assessed), most of the underlying problems have not been resolved. The illegal burning of wheels, plastics, textiles, and other industrial residuals, along with the detection of two thousand toxic substance dumping sites, still represents major concerns of environmental pollution and population health. This review summarizes the most relevant studies, which analyzed chemical contamination (primarily dioxins and polychlorinated biphenyls (PCBs)) of the air, soil, water, animals, and humans in Campania. In addition, we reviewed information on population health (i.e., mortality data, congenital malformations, and cancer incidence). Moving from a detailed mapping of (mostly illegal) waste dumping sites in Campania, we have focused on recent studies which have found: (a) high concentrations of dioxins (≥5.0 pg TEQ/g fat) in milk samples from sheep, cows, and river buffaloes; (b) remarkable contamination of dioxin and PCBs in human milk samples from those living in the Naples and Caserta areas (PCDDs+PCDFs and dioxin-like-PCBs (dl-PCBs) assessed at 16.6 pg TEQ/g of fat; range: 7.5-43 pg/g of fat); (c) potential age-adjusted standardized mortality rates associated with some specific cancer types; (d) a statistically significant association between exposure to illegal toxic waste dumping sites and cancer mortality, even after adjustment by socio-economic factors and other environmental indicators.

Legacy persistent organic pollutants including PBDEs in the trophic web of the Ross Sea (Antarctica).

PubMed

Corsolini, Simonetta; Ademollo, Nicoletta; Martellini, Tania; Randazzo, Demetrio; Vacchi, Marino; Cincinelli, Alessandra

2017-10-01

The ecological features of the Ross Sea trophic web are peculiar and different from other polar food webs, with respect to the use of habitat and species interactions; due to its ecosystem integrity, it is the world's largest Marine Protected Area, established in 2016. Polar organisms are reported to bioaccumulate lipophilic contaminant, viz persistent organic pollutants (POPs). Legacy POPs and flame retardants (polybrominated diphenyl ethers, PBDEs) were studied in key species of the Ross Sea (Euphausia superba, Pleuragramma antarctica) and their predators (Dissostichus mawsoni, Pygoscelis adeliae, Aptenodytes forsteri, Catharacta maccormicki, Leptonychotes weddellii). Gaschromatography revealed the presence of PCBs, HCB, DDTs, PBDEs in most of the samples; HCHs, dieldrin, Eldrin, non-ortho PCBs, PCDDs, PCDFs were detected only in some species. The average ∑PBDEs was 0.19-1.35 pg/g wet wt in the key-species and one-two order of magnitude higher in the predators. Penguins and skuas from an area where a long-term field camp is located showed higher BDE concentrations. The ΣDDTs was higher in the Antarctic toothfish (20 ± 6.73 ng/g wet wt) and in the South Polar skua (5.911 ± 3.425 ng/g wet wt). The TEQs were evaluated and the highest concentration was found in the Weddell seal, due to PCB169, 1,2,3,4,7,8-HxCDF, and 2,3,4,6,7,8-HxCDF. There was no significant relationship between the trophic level and the POP concentrations. Although low concentrations, organisms of the Ross Sea trophic web should be further studied: lack of information on some ecotoxicological features and human impacts including global change may distress the ecosystem with unpredictable effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

Trematomus bernacchii as an indicator of POP temporal trend in the Antarctic seawaters.

PubMed

Cincinelli, Alessandra; Martellini, Tania; Pozo, Karla; Kukučka, Petr; Audy, Ondřej; Corsolini, Simonetta

2016-10-01

The occurrence of POPs in remote areas, such as Antarctica, is the result of their ability to udergo Long Range Transport (LRT) in the atmosphere, precipitation and cold condensation. In this study, both recent levels of various POPs in Trematomus bernacchii and their changes in roughly three decades were determined in order to evaluate trends of POPs in Antarctic benthic seawaters. In fact, Trematomus bernacchii is considered a good sentinel bio-indicator for monitoring not only the extent of contamination by POPs in the Antarctic aquatic ecosystem, but also changes in Antarctic ecosystem quality and trends. A slight decreasing PCB trend was detected during 30-years time span (from early 1980's to 2010) in the circumantarctic seawaters. Two higher peaks of concentrations were reported in 2001 and 2005 in the Ross Sea and they may reflect the ice melting of icebergs. Because fire risk is very high in Antarctica due to the very dry air, a large use of flame retardants in buildings and furniture of stations is highly probable; moreover, many stations were built when there were no restrictions on flame retardants use. The PBDE levels in the T. bernacchii from 2001 to 2011 ranged 0.05-0.35 pg/g and were of the same order of magnitude in 2001/2011 and in 2002/2005, with a maximum value in 2005 (0.35 pg/g). Comparable concentrations of HCB, HCHs PCDDs and PCDFs are available only for few seasons: all these compounds showed a decreasing temporal trends and their concentrations were one or more order of magnitude lower in 2000s-2010s. Copyright © 2015 Elsevier Ltd. All rights reserved.

Validation of a gas chromatography-triple quadrupole mass spectrometry method for confirmatory analysis of dioxins and dioxin-like polychlorobiphenyls in feed following new EU Regulation 709/2014.

PubMed

L'Homme, B; Scholl, G; Eppe, G; Focant, J-F

2015-01-09

The European Regulations laying down methods of sampling and analysis for the EU official control of levels of polychlorodibenzo-p-dioxins (PCDDs), polychloro-dibenzofurans (PCDFs), dioxin-like (DL) and non dioxin-like (NDL) PCBs in food and feed have been recently amended by EU Regulation Nos. 589/2014 and 709/2014. A major update is the recognition of gas chromatography (GC) triple quadrupole mass spectrometry (GC-QQQMS/MS) as a confirmatory tool for checking compliance with maximum levels (ML). These revisions have been initiated since this technology now exhibits similar performances to GC (magnetic sector) high resolution mass spectrometry (GC-HRMS). In this paper, we show a fully validated method for PCDD/Fs and DL-PCBs analysis in feed material of plant origin (vegetable oil) using GC-QQQMS/MS following the dedicated EU Regulation 709/2014. We show that individual analytical criteria (selectivity, linearity, quant/qual MRM transitions, accuracy around ML of 1.50ng WHO2005TEQ/kg, within-lab reproducibility, robustness, and background subtraction) meet the strict requirements set by the EU Regulation. We also propose a clear interpretation of instrumental limit of quantitation (iLOQ) as a 'performance-LOQ', defined in a specific way for GC-QQQMS/MS, and method limit of quantitation (mLOQ) as 'real-LOQ' that is used to report bound results. Eventually, the evaluation of measurement uncertainty, following a top-down approach and data produced with our method, demonstrates similar results than with GC-HRMS, thus offering a reliable alternative to the standard method for vegetable oil. Copyright © 2014 Elsevier B.V. All rights reserved.

In vitro cellular responses in the RTG-2 cell line to complex mixtures of dioxins and dioxin-like PCDDs, PCDFs and PCBs.

PubMed

Babín, María del Mar; Sanz, Paloma; Concejero, Miguel Angel; Martínez, María Angeles; Tarazona, José Vicente

2010-08-01

High-resolution gas chromatography/mass spectrometry (HRGC/MS) is the standard method for analysing dioxin, furan and polybrominated retardants in hazardous waste. Determination of dioxin-like compounds using in vitro bioassays such as ethoxyresorufin-O-deethylase (EROD) is an important tool to evaluate their Ah receptor-mediated toxic effects, because it detects all arylhydrocarbon receptor ligands in a variety of sample matrices. In the present work, we compared RTG-2 cell line EROD bioassay with HRGC/MS for assessing waste samples (liquid and solid) contaminated with polychlorinated dibenzo-p-dioxins and dibenzofurans, polychlorinated biphenyls (dioxin-like PCBs) and other xenobiotics. For liquid samples, HRGC/MS-toxic equivalent (HRGC/MS-TEQ) values ranged from 273.26 to 5.84 ng TEQ l(-1) and correlated well (correlation coefficient 0.99) with values obtained by EROD-TEQ, which ranged from 128 to 2.5 ng TEQ l(-1). For solid samples, HRGC/MS-TEQ values ranged from 3.44 to 0.49 ng TEQ g(-1) and correlated less well than liquid samples (correlation coefficient 0.64) with values obtained by EROD-TEQ ranging from 2.27 to 0.93 ng TEQ g(-1). The overestimation of RTG-2 EROD-TEQ (1.2 +/- 0.92 of values established by HRGC/MS) and the absence of false-negative results may limit analytical costs by eliminating the need for follow-up GC/MS analysis on the negative samples. We suggest that RTG-2 EROD bioassay is an inexpensive means for preliminary dioxin and furan positive screenings of waste samples. (c) 2010 John Wiley & Sons, Ltd.

Fetal exposure markers of dioxins and dioxin-like PCBs.

PubMed

Lampa, Erik; Eguchi, Akifumi; Todaka, Emiko; Mori, Chisato

2018-04-01

Fetal exposure to polychlorinated biphenyls (PCBs), polychlorinated-p-dibenzodioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) have been associated with a number of adverse health outcomes. Although the placenta acts as a barrier between the mother and the fetus, these contaminants transfer through the placenta exposing the fetus. Several studies have investigated placental transfer, but few have assessed the co-variation among these contaminants. Maternal blood, cord blood, and cord tissue were collected from 41 Japanese mother-infant pairs and analyzed for dioxin-like PCBs and PCDD/Fs. Hierarchical cluster analysis followed by principal component analysis were used to assess the co-variation. Two stable clusters of dioxin-like PCBs were found in maternal and cord blood. One cluster of low/medium chlorinated dioxin-like PCBs was present in all three matrices with 2,3',4,4',5-PeCB(#118) and 3,3',4,4',5-PeCB(#126) explaining the majority of the clusters' variances. Medium/high chlorinated dioxin-like PCBs clustered in maternal blood and cord blood but not in cord tissue. 2,3,4,4',5-PeCB(#114) and 2,3,3',4,4',5,5'-HpCB(#189) explained the majority of the clusters' variances. There was a substantial correlation between the sum of dioxin-like PCBs and total PCDD/F in all three matrices. The sum of the four suggested PCBs plus 3,3',4,4'-TeCB(#77) correlated well with total PCDD/F in all three matrices. Apart from the dioxin-like PCBs, little co-variation existed among the studied contaminants. The five PCBs can be used as fetal exposure markers for dioxin and dioxin-like PCBs in maternal and cord blood respectively. In cord tissue, more higher chlorinated dioxin-like PCBs need to be measured as well.

Dioxin-like chemicals in soil and sediment from residential and industrial areas in central South Africa.

PubMed

Nieuwoudt, Claudine; Quinn, Laura P; Pieters, Rialet; Jordaan, Ilse; Visser, Maret; Kylin, Henrik; Borgen, Anders R; Giesy, John P; Bouwman, Henk

2009-08-01

Persistent organic pollutants (POPs) are a global concern due to their ubiquitous presence and toxicity. Currently, there is a lack of information regarding POPs from South Africa. Here we report and interpret concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), -dibenzofurans (PCDFs) and co-planar-biphenyls (PCBs) in soils and sediments collected from central South Africa. High resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS) and the H4IIE-luc bio-assay were used to identify and quantify individual PCDD/F congeners and to report the total concentration of 2,3,7,8-tetrachloro dibenzo-p-dioxin equivalents (TCDD-EQ), respectively. TCDD-EQs determined by use of the bio-assay, and concentrations of WHO(2005)-TEQ (toxic equivalents) determined by chemical analysis, were similar. The limit of detection (LOD) for the bio-assay was 0.82 and 2.8 ng TCDD-EQ kg(-1), dw for sediment and soil, respectively. EQ20 concentrations determined by use of the bio-assay ranged from

Characteristic accumulation of PCDD/Fs in pine needles near an MSWI and emission levels of the MSWI in Pearl River Delta: A case study.

PubMed

Chen, Pei; Xiao, Xiao; Mei, Jun; Cai, Ying; Tang, Yuhui; Peng, Ping'an

2017-08-01

Pine needle samples were collected near a municipal solid waste incinerator (MSWI) in Pearl River Delta, southern China, as well as the stack gas and dust samples of the MSWI were simultaneously collected. Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) were analyzed following the USEPA Method 1613B. The concentration of PCDD/Fs in the pine needles (137-625 ng/kg, 25-51 ng I-TEQ/kg) is the highest level ever detected in China. Congener profile comparison and principal component analysis (PCA) confirmed the MSWI as an important emission source of environmental PCDD/Fs. The PCDD/Fs in the pine needles mainly depended on the atmospheric concentration, exposure time and also the wind direction. The accumulation of PCDD/Fs in this species did not occur at a steady rate, and the total concentrations covered up the actual photolysis information. Gas-phase partitioning of compounds in the atmosphere was the dominant process through which PCDD/Fs were adsorbed onto the pine needle surface in contrast with particle-phase deposition, and subsequent environmental behavior varied between the congeners. Photo-degradation was the major transformation process as PCDD/Fs were adsorbed onto the pine needle surfaces. Higher chlorinated PCDD/Fs were more recalcitrant to photo-degradation than those that were less chlorinated, and PCDDs were more resistant to photo-degradation than PCDFs. On the other hand, the strong ability of lipid-rich pine needles to accumulate dioxin compounds indicates they can be used as the absorption sink of PCDD/Fs in heavily polluted areas because it is easier to dispose of pine needles than it is to clean contaminated air. Copyright © 2017 Elsevier Ltd. All rights reserved.

Emission profiles of polychlorinated dibenzodioxins, polychlorinated dibenzofurans (PCDD/Fs), dioxin-like PCBs and hexachlorobenzene (HCB) from secondary metallurgy industries in Portugal.

PubMed

Antunes, Pedro; Viana, Paula; Vinhas, Tereza; Rivera, J; Gaspar, Elvira M S M

2012-09-01

This paper reports, for the first time, a study of dioxin emissions from 10 siderurgies and metallurgies, secondary copper, aluminum and lead metallurgies, in Portugal. The study reports the emission factors and total emission amounts of PCDD/Fs, dioxin-like PCBs and hexachlorobenzene (HCB). The congener patterns were characterized and are discussed. The results showed that the total amount of PCDFs is higher than PCDDs in flue gas of each industrial unit. The toxic equivalent emission factors of pollutants emitted are 3098-3338 ngI-TEQt(-1) for PCDD/Fs and 597-659 ng I-TEQt(-1) for dioxin-like PCBs in siderurgies production (total estimated emission amounts released to atmosphere of 3.9-4.5 g I-TEQyr(-1)), 50-152 ng I-TEQt(-1) for PCDD/Fs and 24-121 ng I-TEQt(-1) for dioxin-like PCBs in ferrous foundries production (total estimated emission amounts released to atmosphere of 0.0010-0.0016 g I-TEQyr(-1)) and 5.8-5715 ng I-TEQt(-1) for PCDD/Fs and 0.49-259 ng I-TEQt(-1) for dioxin-like PCBs in non-ferrous foundries production (total estimated emission amounts released to atmosphere of 0.00014-0.12 g I-TEQyr(-1)). The HCB emission from siderurgies production is 0.94-3.2 mg t(-1) (total estimated emission amounts released 0.94-3.8 g yr(-1)), being much smaller, residual, in the emissions of the other types of plants (0.0012-0.026 mg t(-1) production and total estimated emission amounts released to atmosphere of 0.013-1.7 mg yr(-1)). Copyright © 2012 Elsevier Ltd. All rights reserved.

Results of the second national forest soil inventory in Germany - Interpretation of level and stock profiles for PCDD/F and PCB in terms of vegetation and humus type.

PubMed

Pandelova, Marchela; Henkelmann, Bernhard; Bussian, Bernd M; Schramm, Karl-Werner

2018-01-01

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) were detected in 86 humic topsoil layers and in a subset of 11 randomly selected top mineral forest soils at the depths of 0-5cm and 5-10cm collected from different federal states of Germany. The distribution of these persistent organic pollutants (POPs) in humic topsoils with respect to vegetation cover (coniferous vs. deciduous vs. mixed), total organic carbon (TOC), altitude and latitude data was investigated. There is cross correlation between the contents and TOC while the correlation with latitude indicates higher abundances of POPs in central Germany where there is high population density accompanied with industrial activities. The calculated stocks suggest that humus type (mor, mull, or moder) in conjunction with forest type can explain the relative POPs abundances in different soil layers. Generally, humic topsoils show highest contents of POPs compare to the two mineral soils with a ratio of 100:10:1. However, the stock humic layers of coniferous stands contribute about 50% to the total stock, whereas at deciduous stands the stock is mainly located in the upper mineral soil layer (0-5cm). The soil-water distribution coefficients (Kd) were calculated to estimate the potential translocation in the different soil types. The Kd values vary among the PCBs and PCDD/Fs congeners and are most variable for humic topsoils. There is pronounced chemical abundance in the top mineral soils with increasing Kd and this points to non-water bound transport processes for superlipophilic compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

Ultra-trace measurement of Dechloranes to investigate food as a route of human exposure.

PubMed

L'Homme, Benjamin; Calaprice, Chiara; Calvano, Cosima Damiana; Zambonin, Carlo; Leardi, Riccardo; Focant, Jean-François

2015-11-01

Dechloranes, including Dechlorane Plus (syn- and anti-isomers), Dechlorane 602, Dechlorane 603, Dechlorane 604, Chlordene Plus, and Mirex are used as flame-retardants and were recently found in human serum of the European population. In order to investigate if food consumption would possibly be a significant route of exposure, we developed a method for the measurement of Dechloranes in food and feed. We showed that it was possible to extend the scope of the regular polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin like (DL-), and non-dioxin like (NDL-) regulated PCBs clean-up and fractionation procedure to Dechloranes and that no compound degradation occurred during the strong acidic treatments used for lipid digestion. Dechloranes were measured by gas chromatography coupled to triple quadrupole mass spectrometry (GC-QQQMS/MS). We optimized injection parameters by face centered experimental design (FCD). The electron ionization fragmentation was investigated to set appropriate multiple reaction monitoring (MRM) transitions. Instrumental and method limits of quantitation (iLOQs and mLOQs) were determined following EU guidelines for dioxin analyses in food. A total of 88 samples were analyzed to assess the prevalence of this route of exposure to humans. Average levels of the sum of Dechloranes ranged from 10 to 31pg/g fat, with the exception of fish, feed additives, and corn that were reported in pg/g wet weight at average levels of 9, 12, and 2pg/g ww. Based on Belgian food habits, a dietary intake was estimated to be 136pg/day. The relatively low reported levels indicate that other routes of human exposure should be considered. Copyright © 2015 Elsevier Ltd. All rights reserved.

Assessing polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in air across Latin American countries using polyurethane foam disk passive air samplers.

PubMed

Schuster, Jasmin K; Harner, Tom; Fillmann, Gilberto; Ahrens, Lutz; Altamirano, Jorgelina C; Aristizábal, Beatriz; Bastos, Wanderley; Castillo, Luisa Eugenia; Cortés, Johana; Fentanes, Oscar; Gusev, Alexey; Hernandez, Maricruz; Ibarra, Martín Villa; Lana, Nerina B; Lee, Sum Chi; Martínez, Ana Patricia; Miglioranza, Karina S B; Puerta, Andrea Padilla; Segovia, Federico; Siu, May; Tominaga, Maria Yumiko

2015-03-17

A passive air sampling network has been established to investigate polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) at Global Atmospheric Passive Sampling (GAPS) sites and six additional sites in the Group of Latin American and Caribbean Countries (GRULAC) region. The air sampling network covers background, agricultural, rural, and urban sites. Samples have been collected over four consecutive periods of 6 months, which started in January 2011 [period 1 (January to June 2011), period 2 (July to December 2011), period 3 (January to June 2012), and period 4 (July 2012 to January 2013)]. Results show that (i) the GAPS passive samplers (PUF disk type) and analytical methodology are adequate for measuring PCDD/F burdens in air and (ii) PCDD/F concentrations in air across the GRULAC region are widely variable by almost 2 orders of magnitude. The highest concentrations in air of Σ4-8PCDD/Fs were found at the urban site São Luis (Brazil, UR) (i.e., 2560 fg/m3) followed by the sites in São Paulo (Brazil, UR), Mendoza (Argentina, RU), and Sonora (Mexico, AG) with values of 1690, 1660, and 1610 fg/m3, respectively. Very low concentrations of PCDD/Fs in air were observed at the background site Tapanti (Costa Rica, BA), 10.8 fg/m3. This variability is attributed to differences in site characteristics and potential local/regional sources as well as meteorological influences. The measurements of PCDD/Fs in air agree well with model-predicted concentrations performed using the Global EMEP Multimedia Modeling System (GLEMOS) and emission scenario constructed on the basis of the UNEP Stockholm Convention inventory of dioxin and furan emissions.

Identifying source regions for the atmospheric input of PCDD/Fs to the Baltic Sea

NASA Astrophysics Data System (ADS)

Sellström, Ulla; Egebäck, Anna-Lena; McLachlan, Michael S.

PCDD/F contamination of the Baltic Sea has resulted in the European Union imposing restrictions on the marketing of several fish species. Atmospheric deposition is the major source of PCDD/Fs to the Baltic Sea, and hence there is a need to identify the source regions of the PCDD/Fs in ambient air over the Baltic Sea. A novel monitoring strategy was employed to address this question. During the winter of 2006-2007 air samples were collected in Aspvreten (southern Sweden) and Pallas (northern Finland). Short sampling times (24 h) were employed and only samples with stable air mass back trajectories were selected for analysis of the 2,3,7,8-substituted PCDD/F congeners. The range in the PCDD/F concentrations from 40 samples collected at Aspvreten was a factor of almost 50 (range 0.6-29 fg TEQ/m 3). When the samples were grouped according to air mass origin into seven compass sectors, the variability was much lower (typically less than a factor of 3). This indicates that air mass origin was the primary source of the variability. The contribution of each sector to the PCDD/F contamination over the Baltic Sea during the winter half year of 2006/2007 was calculated from the average PCDD/F concentration for each sector and the frequency with which the air over the Baltic Sea came from that sector. Air masses originating from the south-southwest, south-southeast and east segments contributed 65% of the PCDDs and 75% of the PCDFs. Strong correlations were obtained between the concentrations of most of the PCDD/F congeners and the concentration of soot. These correlations can be used to predict the PCDD/F concentrations during the winter half year from inexpensive soot measurements.

An effective and low cost carbon based clean-up method for PCDD/Fs and PCBs analysis in food.

PubMed

Kedikoglou, Kleopatra; Costopoulou, Danae; Vassiliadou, Irene; Bakeas, Evangelos; Leondiadis, Leondios

2018-09-01

Sample preparation is of critical importance in dioxin analysis of food and feed samples. It is a complex procedure that includes lipid extraction followed by the application of chromatographic separation techniques, aiming in removing undesirable interferences from the matrix. The separation of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) from polychlorinated biphenyls (PCBs) is achieved by carbon-based materials which should have high fat capacity in order to be suitable for lipid-containing matrices. Automated methods are available but due to high cost and use of high amounts of solvents, manual methods are also applied. An active carbon material (Carbosphere) with high fat capacity that has been used in the past for manual methods is no longer commercially available. The present study assesses an alternative active carbon material, FU 4652, that can be used for the separation of PCDD/Fs and non-ortho PCBs. Mono-ortho and 6 non-dioxin-like PCBs are also analyzed. The method was validated according to the analytical criteria set in EU regulations 589/2014 and 709/2014. Control samples analyzed for the evaluation of the above material were olive oil reference samples spiked with PCDD/Fs and dioxin-like PCBs at two concentration levels. The new method was tested successfully on food samples of interlaboratory trials organized in previous years. Farmed fish samples collected within national surveillance programs for the years 2016-2017 were analyzed with the method developed. The results obtained indicate that the FU 4652 carbon sorbent has high fat capacity and is capable of separating congeners with good recoveries. Copyright © 2018 Elsevier Ltd. All rights reserved.

Persistent organic pollutants (PCDD/Fs, dioxin-like PCBs, marker PCBs, and PBDEs) in health supplements on the Spanish market.

PubMed

Martí, M; Ortiz, X; Gasser, M; Martí, R; Montaña, M J; Díaz-Ferrero, J

2010-03-01

During the last years, consumption of health supplements has increased in our society. They are recommended as an additional source of minerals, vitamins, omega-3 and omega-6 fatty acids, in the diet. A lot of these supplements contain oils among their components (fish oils or vegetable oils), especially those recommended for their omega-3 content. Due to their persistence and lipophilic characteristics, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (PCBs), marker PCBs, and polybrominated diphenyl ethers (PBDEs) bioaccumulate in fat tissues, especially in those animals, as fish, which show low metabolic capability. Therefore, the consumption of nutritional supplements with oil components can increase the intake of persistent organic pollutants (POPs) through the diet. The aim of this study was to analyse 15 of these supplements commercialized in Spain to determinate their POPs concentrations and their intake for their consumers. Concentrations of POPs in the dietary supplements studied (PCDD/Fs: 0.04-2.4 pg TEQ g(-1); dl-PCBs: 0.01-12.1 pg TEQ g(-1); marker PCBs: 0.17-116 ng g(-1); and PBDEs: 0.07-18.2 ng g(-1)) were in the low-medium range of those reported in literature for other countries. Vegetable oil and mineral-based supplements showed concentrations of POPs clearly lower than those based on fish oil. Among these, those based on cod liver oil presented the highest concentrations detected in the study, exceeding the maximum levels established in European regulations for marine oils for human consumption. In general, the intake of POPs via the consumption of these supplements would be lower than the intake derived from fish consumption. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Dioxins, furans and polycyclic aromatic hydrocarbons emissions from a hospital and cemetery waste incinerator

NASA Astrophysics Data System (ADS)

Mininni, Giuseppe; Sbrilli, Andrea; Maria Braguglia, Camilla; Guerriero, Ettore; Marani, Dario; Rotatori, Mauro

An experimental campaign was carried out on a hospital and cemetery waste incineration plant in order to assess the emissions of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polycyclic aromatic hydrocarbons (PAHs). Raw gases were sampled in the afterburning chamber, using a specifically designed device, after the heat recovery section and at the stack. Samples of slags from the combustion chamber and fly ashes from the bag filter were also collected and analyzed. PCDD/Fs and PAHs concentrations in exhaust gas after the heat exchanger (200-350 °C) decreased in comparison with the values detected in the afterburning chamber. Pollutant mass balance regarding the heat exchanger did not confirm literature findings about the de novo synthesis of PCDD/Fs in the heat exchange process. In spite of a consistent reduction of PCDD/Fs in the flue gas treatment system (from 77% up to 98%), the limit of 0.1 ng ITEQ Nm -3 at the stack was not accomplished. PCDD/Fs emission factors for air spanned from 2.3 up to 44 μg ITEQ t -1 of burned waste, whereas those through solid residues (mainly fly ashes) were in the range 41-3700 μg ITEQ t -1. Tests run with cemetery wastes generally showed lower PCDD/F emission factors than those with hospital wastes. PAH total emission factors (91-414 μg kg -1 of burned waste) were in the range of values reported for incineration of municipal and industrial wastes. In spite of the observed release from the scrubber, carcinogenic PAHs concentrations at the stack (0.018-0.5 μg Nm -3) were below the Italian limit of 10 μg Nm -3.

PCDD/Fs atmospheric deposition fluxes and soil contamination close to a municipal solid waste incinerator.

PubMed

Vassura, Ivano; Passarini, Fabrizio; Ferroni, Laura; Bernardi, Elena; Morselli, Luciano

2011-05-01

Bulk depositions and surface soil were collected in a suburban area, near the Adriatic Sea, in order to assess the contribution of a municipal solid waste incinerator to the area's total contamination with polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs and PCDFs). Samples were collected at two sites, situated in the area most affected by plant emissions (according to the results of the Calpuff air dispersion model), and at an external site, considered as a reference. Results show that the studied area is subject to low contamination, as far as these compounds are concerned. Deposition fluxes range from 14.3 pg m(-2)d(-1) to 89.9 pg m(-2)d(-1) (0.75 pg-TEQ m(-2)d(-1) to 3.73 pg-TEQ m(-2)d(-1)) and no significant flow differences are observed among the three monitored sites. Total soil concentration amounts to 93.8 ng kg(-1) d.w. and 1.35 ng-TEQ kg(-1)d.w, on average, and confirms a strong homogeneity in the studied area. Furthermore, from 2006 to 2009, no PCDD/Fs enrichment in the soil was noticed. Comparing the relative congener distributions in environmental samples with those found in stack emissions from the incineration plant, significant differences are observed in the PCDD:PCDF ratio and in the contribution of the most chlorinated congeners. From this study we can conclude that the incineration plant is not the main source of PCDD/Fs in the studied area, which is apparently characterized by a homogeneous and widespread contamination situation, typical of an urban area. Copyright © 2011 Elsevier Ltd. All rights reserved.

Adsorption of TCDD with 1-butyl-3-methylimidazolium dicyanamide ionic liquid: a combined molecular dynamics simulation and quantum chemistry study.

PubMed

Pan, Wenxiao; Qi, Yuanyuan; Wang, Ruoxi; Han, Zhe; Zhang, Dongju; Zhan, Jinhua

2013-04-01

The effective abatement of flue gas emissions, especially polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), is one of the challenging issues in the field of environmental science currently. Imidazolium-based dicyanamide ionic liquids (ILs) were proposed to have potential in controlling the emissions of PCDD/Fs. However, the relevant mechanism at the molecular level still remains unclear. To address this subject, we here present a combined molecular dynamics (MD) simulation and quantum chemical (QM) study on the adsorption of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the most toxic congener among PCDD/F family, by 1-butyl-3-methylimidazolium dicyanamide IL, a representative imidazolium dicyanoamide ILs, which were demonstrated to possess high capture capability for PCDD/Fs. The MD simulation results show that TCDD molecules can be effectively adsorbed on the IL surface to form a dense layer, but cannot enter the interior of the IL. The results of QM calculations show that the adsorption of TCDDs on the IL surface occurs via intra-molecular hydrogen bond interactions. The calculated interaction energy of the anion with TCDD molecule is two times more than that of the cation, implying that the IL anion dominates the interaction with TCDD molecules, while the cation plays a secondary role. Based on the calculated results, we propose that imidazolium dicyanamide IL films/membranes may be better materials than the corresponding bulk for capturing TCDD. The present theoretical results may be helpful to designing the functional ILs which effectively capture and concentrate PCDD/F compounds. Copyright © 2013 Elsevier Ltd. All rights reserved.

Occurrence of brominated persistent organic pollutants (PBDD/DFs, PXDD/DFs, and PBDEs) in Baltic wild salmon ( Salmo salar ) and correlation with PCDD/DFs and PCBs.

PubMed

Zacs, Dzintars; Rjabova, Jekaterina; Bartkevics, Vadims

2013-08-20

The contamination profiles of polybrominated dibenzo-p-dioxins (PBDDs), dibenzofurans (PBDFs), diphenyl ethers (PBDEs), and mixed monobromo/chloro dibenzo-p-dioxins (PXDDs) and dibenzofurans (PXDFs) were determined in the tissue of Baltic wild salmon and compared with those of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs). Out of the analyzed PXDD/DFs, only the 3-B-2,7,8-triCDF was detected (in the concentration range of 0.039-0.075 pg g(-1) fresh weight (f.w.)). The toxic equivalents (TEQs) for analyzed PBDD/DFs (0.074-0.142 pg TEQ g(-1) f.w.) were found to contribute on average 2.1% to the total PCDD/DF-PBDD/DF-TEQ. The total concentrations of 27 PBDE congeners were in the range of 1.3-5.6 ng g(-1) f.w., with an average of 3.3 ng g(-1) f.w. The levels of PCDD/DFs and PCBs were found to be in the range of 4.53-14.6 pg WHO(2005)-PCDD/DF-PCB-TEQ g(-1) f.w., and concentrations of these compounds in most of the analyzed samples were above the maximum levels specified in Commission Regulation (EU) No. 1259/2011. Good correlation was observed between WHO(2005)-PCDD/DF-TEQ and WHO(2005)-PCB-TEQ (r(2) = 0.98), and these parameters were well correlated with the total sum of PBDE concentrations (r(2) = 0.91 and r(2) = 0.94, respectively). The results suggest that the consumption of Baltic wild salmon has no crucial impact on the average POP intake for typical Latvians.

Chlorinated hydrocarbons in livers of American mink (Mustela vison) and river otter (Lutra canadensis) from the Columbia and Fraser River Basins, 1990-1992

USGS Publications Warehouse

Elliott, J.E.; Henny, Charles J.; Harris, M.L.; Wilson, L.K.; Norstrom, R.J.

1999-01-01

We investigated chlorinated hydrocarbon contaminants in aquatic mustelid species on the Fraser and Columbia Rivers of northwestern North America. Carcasses of river otter (Lutra canadensis) (N=24) and mink (Mustela vison) (N=34) were obtained from commercial trappers during the winters of 1990-91 and 1991a??92. Pooled liver samples were analyzed for organochlorine pesticides, polychlorinated biphenyls (PCBs), including non-ortho congeners, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Most samples contained detectable concentrations of DDE, PCBs, although there was substantial variability in patterns and trends among neighboring samples. Concentrations of DDE were in some mink and several otter samples from the lower Columbia River elevated (to 4700 g/kg wet weight); excluding one mink sample from the Wenatchee area, mean DDE levels generally decreased between 1978a??79 and 1990a??92. PCBs were present in all samples. PCB concentrations in otter livers collected from the lower Columbia were ten-fold lower than measured a decade previously; nevertheless, a sample taken near Portland had a mean concentration of 1500 g/kg, within a range of concentrations associated with reproductive effects in captive mink. Concentrations of 2,3,7,8-TCDD and TCDF were generally below detection limits, except for one otter collected near a pulp mill at Castlegar, on the upper Columbia, with 11 ng TCDD/kg in liver. Elevated concentrations of higher chlorinated PCDD/Fs, probably resulting from use of chlorophenolic wood preservatives, were found in both species; one otter sample from the lower Columbia had 2200 ng OCDD/kg. International TCDD toxic equivalent levels in mink (31 ng/kg) and otter (93 ng/kg) from the lower Columbia River approached toxicity thresholds for effects on reproduction in ranch mink.

Seasonal variations of PCDD/Fs congeners in air, soil and eggs from a Polish small-scale farm.

PubMed

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.

Formation of polychlorinated diphenyl ethers from condensation of chlorophenols with chlorobenzenes.

PubMed

Liu, Wenxia; Zheng, Minghui; Liu, Wenbin; Ma, Xiaodong; Qian, Yong; Zhang, Bing

2008-01-01

Polychlorinated diphenyl ethers (PCDEs), which are among the members of persistent organic pollutants, and PCDEs have been determined in a number of environmental samples. The main possible sources are the technical production of chlorinated phenols and all processes of incomplete combustion. PCDEs were observed in the fly ash from a municipal waste incinerator (MWI). It was speculated that the condensation of chlorophenols with chlorobenzenes occurred via PCDEs to form polychlorinated dibenzofurans (PCDFs). Nevertheless, PCDEs formation from condensation of chlorophenols with chlorobenzenes has not been confirmed by experimental observation. The objective of this paper is to investigate the formation mechanism of PCDEs from the condensation of chlorophenols with chlorobenzenes. The results are expected to be helpful in understanding the formation of PCDEs and in controlling and abating PCDEs emissions from MWI. The pyrolysis of pentachlorophenol (PCP) and/or polychlorobenzenes (PCBz) was carried out in a sealed glass tube. The reaction products were extracted and purified with K2CO3 solution. The samples were concentrated and then cleaned up on an alumina column. GC/MS was used for identification and quantification of reaction products. The results showed that the pyrolysis of hexachlorobenzene (HCB) at 340 degrees C for 6 h led to the formation of decachlorodiphenyl ether (DCDE) (2.41 microg/mg) and octachlorodibenzo-p-dioxins (OCDD) (0.24 micropg/mg), while the pyrolysis of PCP yielded DCDE (13.08 microg/mg) and OCDD (180.13 microg/mg). In addition, the amount of DCDE formation from the pyrolysis of the mixture of PCP and HCB was 4.65 times higher than the total amount of DCDE formation from the pyrolysis of HCB and PCP, respectively. This indicated that PCP and HCB were prone to condensation and formation of DCDE. DCDE was the main congener of PCDEs from condensation of PCP with HCB at 340, 400 and 450 degrees C. A small amount of nonachlorodiphenyl ether (NCDE) was formed by dechlorination reaction at 450 degrees C. The condensation of PCP with 1,2,4,5-tetrachlorobenzene (Cl4Bz) formed 2,2',3,4,4',5,5',6-octachlorodiphenyl ether (OCDE). Small amounts of heptachlorodiphenyl ether (HpCDE) and hexachlorodiphenyl ether (HxCDE) were detected at 450 degrees C. Meanwhile, polychlorinated dibenzo-p-dioxins (PCDDs) and PCDFs were detected from the condensation of PCP and PCBz. Experimental studies clarified the behavior of the formation of PCDEs from condensation of polychlorophenols and PCBz. The condensation of polychlorophenols with PCBz formed PCDEs through elimination of HCl between polychlorophenols and PCBz molecules. Another pathway of PCDEs formation was elimination of H2O between two polychlorophenol molecules. In addition, dechlorination processes had caused the specific homologous pattern of PCDEs under higher temperatures.

Impacts of Perinatal Dioxin Exposure on Motor Coordination and Higher Cognitive Development in Vietnamese Preschool Children: A Five-Year Follow-Up

PubMed Central

Tran, Nghi Ngoc; Pham, Tai The; Ozawa, Kyoko; Nishijo, Muneko; Nguyen, Anh Thi Nguyet; Tran, Tuong Quy; Hoang, Luong Van; Tran, Anh Hai; Phan, Vu Huy Anh; Nakai, Akio; Nishino, Yoshikazu; Nishijo, Hisao

2016-01-01

Dioxin concentrations remain elevated in the environment and in humans residing near former US Air Force bases in South Vietnam. Our previous epidemiological studies showed adverse effects of dioxin exposure on neurodevelopment for the first 3 years of life. Subsequently, we extended the follow-up period and investigated the influence of perinatal dioxin exposure on neurodevelopment, including motor coordination and higher cognitive ability, in preschool children. Presently, we investigated 176 children in a hot spot of dioxin contamination who were followed up from birth until 5 years old. Perinatal dioxin exposure levels were estimated by measuring dioxin levels in maternal breast milk. Dioxin toxicity was evaluated using two indices; toxic equivalent (TEQ)-polychlorinated dibenzo-p-dioxins/furans (PCDDs/Fs) and concentration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Coordinated movements, including manual dexterity, aiming and catching, and balance, were assessed using the Movement Assessment Battery for Children, Second Edition (Movement ABC-2). Cognitive ability was assessed using the nonverbal index (NVI) of the Kaufman Assessment Battery for Children, Second Edition (KABC-II). In boys, total test and balance scores of Movement ABC-2 were significantly lower in the high TEQ- PCDDs/Fs group compared with the moderate and low exposure groups. NVI scores and the pattern reasoning subscale of the KABC-II indicating planning ability were also significantly lower in the high TCDD exposure group compared with the low exposure group of boys. However, in girls, no significant differences in Movement ABC-2 and KABC-II scores were found among the different TEQ-PCDDs/Fs and TCDD exposure groups. Furthermore, in high risk cases, five boys and one girl highly exposed to TEQ-PCDDs/Fs and TCDD had double the risk for difficulties in both neurodevelopmental skills. These results suggest differential impacts of TEQ-PCDDs/Fs and TCDD exposure on motor coordination and higher cognitive ability, respectively. Moreover, high TEQ-PCDDs/Fs exposure combined with high TCDD exposure may increase autistic traits combined with developmental coordination disorder. PMID:26824471

Impacts of Perinatal Dioxin Exposure on Motor Coordination and Higher Cognitive Development in Vietnamese Preschool Children: A Five-Year Follow-Up.

PubMed

Tran, Nghi Ngoc; Pham, Tai The; Ozawa, Kyoko; Nishijo, Muneko; Nguyen, Anh Thi Nguyet; Tran, Tuong Quy; Hoang, Luong Van; Tran, Anh Hai; Phan, Vu Huy Anh; Nakai, Akio; Nishino, Yoshikazu; Nishijo, Hisao

2016-01-01

Dioxin concentrations remain elevated in the environment and in humans residing near former US Air Force bases in South Vietnam. Our previous epidemiological studies showed adverse effects of dioxin exposure on neurodevelopment for the first 3 years of life. Subsequently, we extended the follow-up period and investigated the influence of perinatal dioxin exposure on neurodevelopment, including motor coordination and higher cognitive ability, in preschool children. Presently, we investigated 176 children in a hot spot of dioxin contamination who were followed up from birth until 5 years old. Perinatal dioxin exposure levels were estimated by measuring dioxin levels in maternal breast milk. Dioxin toxicity was evaluated using two indices; toxic equivalent (TEQ)-polychlorinated dibenzo-p-dioxins/furans (PCDDs/Fs) and concentration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Coordinated movements, including manual dexterity, aiming and catching, and balance, were assessed using the Movement Assessment Battery for Children, Second Edition (Movement ABC-2). Cognitive ability was assessed using the nonverbal index (NVI) of the Kaufman Assessment Battery for Children, Second Edition (KABC-II). In boys, total test and balance scores of Movement ABC-2 were significantly lower in the high TEQ- PCDDs/Fs group compared with the moderate and low exposure groups. NVI scores and the pattern reasoning subscale of the KABC-II indicating planning ability were also significantly lower in the high TCDD exposure group compared with the low exposure group of boys. However, in girls, no significant differences in Movement ABC-2 and KABC-II scores were found among the different TEQ-PCDDs/Fs and TCDD exposure groups. Furthermore, in high risk cases, five boys and one girl highly exposed to TEQ-PCDDs/Fs and TCDD had double the risk for difficulties in both neurodevelopmental skills. These results suggest differential impacts of TEQ-PCDDs/Fs and TCDD exposure on motor coordination and higher cognitive ability, respectively. Moreover, high TEQ-PCDDs/Fs exposure combined with high TCDD exposure may increase autistic traits combined with developmental coordination disorder.

Neurocognitive Changes among Elderly Exposed to PCBs/PCDFs in Taiwan

PubMed Central

Lin, Kao-Chang; Guo, Nai-Wen; Tsai, Pei-Chien; Yang, Chiu-Yueh; Guo, YueLiang Leon

2008-01-01

Background In 1979 approximately 2,000 people were exposed to polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans (PCDFs) due to ingestion of contaminated cooking oil in Taiwan. Although a previous study has shown delayed developmental milestones and poorer neurocognitive functioning in children born to exposed mothers, it is unclear whether neurocognitive functioning was impaired in people who were directly exposed to the PCBs and PDCFs. Objective The objective of this study was to compare neurocognitive functioning in people exposed to PCBs and PCDFs with that of unexposed sex- and age-matched neighbors. Methods We conducted a retrospective cohort study among exposed and unexposed subjects ≥60 years of age using prospective outcome measurements. We evaluated neurocognitive tests including cognition, memory modalities, learning, motor and sensory function, mood, and daily activity. Results In total, 162 (59%) exposed and 151 (55%) reference subjects completed this study. In exposed men, all test results were similar to the reference group; however, exposed women had reduced functioning in attention and digit span (ADS), visual memory span (VMS), and verbal memory recalls (VMR), especially learning ability. We also found a borderline reduction in the Mini-Mental State Examination. The digit symbol, motor, sensory, depression (determined by the Geriatric Depression Scale-Short Form), and activity of daily life were not different between the exposed and reference groups. A significant dose–response relationship was found for VMR, ADS, and VMS. Conclusion Our study showed dose-dependent neurocognitive deficits in certain aspects of attention, visual memory, and learning ability in women previously exposed to PCBs and PCDFs, but not in exposed men. PMID:18288316

Dioxin levels in fertilizers from Belgium: determination and evaluation of the potential impact on soil contamination.

PubMed

Elskens, M; Pussemier, L; Dumortier, P; Van Langenhove, K; Scholl, G; Goeyens, L; Focant, J F

2013-06-01

Dioxins are harmful persistent organic pollutants (POPs) to which humans are exposed mostly via the consumption of animal products. They can enter the food chain at any stage, including crop fertilization. Fertilizers belong to several categories: synthetic chemicals providing the essential elements (mostly N, P and K) that are required by the crops but also organic fertilizers or amendments, liming materials, etc. Ninety-seven samples of fertilizers were taken in Belgium during the year 2011 and analyzed after a soft extraction procedure for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (DL-PCBs) using GC-IDHRMS. Only small qualitative differences could be observed between the main fertilizer categories since the PCDD:PCDF:DL-PCB average ratio obtained with the results expressed in TEQ was often close to 30:30:40 (typically for sewage sludge) or 40:30:30 (typically for compost). The median dioxin levels determined were generally lower than recorded previously and were the highest for sewage sludge and compost (5.6 and 5.5 ng TEQ/kg dry weight (dw), respectively). The levels in other fertilizers were lower including manure for which the median value was only 0.2 ng TEQ/kg dw. Several fertilization scenarios relying on the use of those fertilizers were assessed taking into consideration the application conditions prevailing in Belgium. From this assessment it could be concluded that the contribution of fertilizers to the overall soil contamination will be low by comparison of other sources of contamination such as atmospheric depositions. At the field scale, intensive use of compost and sewage sludge will increase dramatically the dioxin inputs compared with other fertilization practices but this kind of emission to the soil will still be relatively low compared to the dioxin atmospheric depositions. Copyright © 2013 Elsevier B.V. All rights reserved.

An egg injection method for assessing early life stage mortality of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in rainbow trout, (Oncorhynchus mykiss)

USGS Publications Warehouse

Walker, M.K.; Hufnagle, L.C.; Clayton, M.K.; Peterson, R.E.

1992-01-01

To characterize the risk that polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) pose to salmonid early life stage survival, we developed a method to expose rainbow trout (Oncorhynchus mykiss) eggs to graded doses of PCDD, PCDF, and PCB congeners, using 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as a prototype. Rainbow trout eggs were injected 24–50 h post-fertilization with 0.2 μl of 50 mM phosphatidylcholine (PC) liposomes (control) or 0.2 μl of 5–7 graded doses of TCDD incorporated into 50 mM PC liposomes. Injection volume never exceeded 0.6% egg volume. Immediately following injection, the injection site was sealed with Super glue®, resulting in 92–97% of TCDD dose retained by the egg. Following both egg injection and waterborne egg exposure. TCDD toxicity in rainbow trout was manifested by half-hatching mortality but predominantly by sac fry mortality associated with hemorrhages, pericardial edema, and yolk sac edema. TCDD LD50s, following injection and waterborne exposure of rainbow trout eggs, were 421 (331–489) and 439 (346–519) pg TCDD/g egg (LD50, 95% fiducial limits), respectively. As in rainbow trout, TCDD toxicity in lake trout (Salvelinus namaycush) following the same two routes of exposure was manifested by half-hatching mortality but predominantly by sac fry mortality preceded by hemorrhages and yolk sac edema. LD50s, based on the dose of TCDD in lake trout eggs, were 47 (21–65) and 65 (60–71) pg/g following injection and waterborne exposure, respectively. The egg injection method is ideal for assessing the relationship between early life stage mortality in rainbow trout and graded egg doses of individual PCDD, PCDF, or PCB congeners.

PCDD, PCDF, dl-PCB and organochlorine pesticides monitoring in São Paulo City using passive air sampler as part of the Global Monitoring Plan.

PubMed

Tominaga, M Y; Silva, C R; Melo, J P; Niwa, N A; Plascak, D; Souza, C A M; Sato, M I Z

2016-11-15

The persistent organic pollutants (POPs), such as organochlorine pesticides and PCBs, are ordinarily monitored in the aquatic environment or in soil in the environmental quality monitoring programs in São Paulo, Brazil. One of the core matrices proposed in the POPs Global Monitoring Plan (GMP) from the Stockholm Convention list is the ambient air, which is not a usual matrix for POPs monitoring in the country. In this study POP levels were evaluated in the air samples from an urban site in São Paulo City over five years, starting in 2010 as a capacity building project for Latin America and the Caribbean region for POP monitoring in ambient air using passive samplers. Furthermore, after the end of the Project in 2012, the monitoring continued in the same sampling site as means to improving the analytical capacity building and contribute to the GMP data. The POPs monitored were 17 congeners of 2,3,7,8 chloro-substituted PCDDs and PCDFs, dioxin-like PCBs, indicator PCBs, organochlorine pesticides and toxaphene. The results show a slight decrease in PCDD/F, dl-PCBs and indicator PCBs levels along the five years. The organochlorine pesticide endosulfan was present at its highest concentration at the beginning of the monitoring period, but it was below detection level in the last year of the monitoring. Some other organochlorine pesticides were detected close to or below quantitation limits. The compounds identified were dieldrin, chlordane, α-HCH, γ-HCH, heptachlor, heptachlor epoxide, hexachlorobenzene and DDTs. Toxaphene congeners were not detected. These results have confirmed the efficacy of passive sampling for POP monitoring and the capacity building for POP analysis and monitoring was established. However more needs to be done, including expansion of sampling sites, new POPs and studies on sampling rates to be considered in calculating the concentration of POPs in ambient air using a passive sampler. Copyright © 2016 Elsevier B.V. All rights reserved.

Pilot-scale incineration of wastes with high content of chlorinated and non-halogenated organophosphorus flame retardants used as alternatives for PBDEs.

PubMed

Matsukami, Hidenori; Kose, Tomohiro; Watanabe, Mafumi; Takigami, Hidetaka

2014-09-15

Chlorinated and non-halogenated organophosphorus flame retardants (OPFRs) including tris(2-chloroisopropyl) phosphate (TCIPP), diethylene glycol bis(di(2-chloroisopropyl) phosphate) (DEG-BDCIPP), triphenyl phosphate (TPHP), and bisphenol A bis(diphenyl phosphate) (BPA-BDPP) have been used increasingly as alternatives to polybrominated diphenyl ethers and other brominated flame retardants. For this study, five batches of incineration experiments of wastes containing approximately 1% of TCIPP, DEG-BDCIPP, TPHP, and BPA-BDPP were conducted using a pilot-scale incinerator. Destruction and emission behaviors of OPFRs were investigated along with the effects on behaviors of unintentional persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs), hexachlorobenzene (HCB), pentachlorobenzene (PeCB), and pentachlorophenol (PCP). Incineration conditions were chosen according to current regulations for waste incinerators in Japan and UNEP. The OPFRs in the input materials were mainly destroyed in the primary combustion with destruction efficiencies greater than 99.999%. Concentrations of the OPFRs in the exhaust gases and ash were, respectively, <0.01-0.048 μg m(-3) and <0.5-68 μg kg(-1). Almost all of the total phosphorus in the input materials was partitioned into the ash, but less into final exit gases, indicating negligible emissions of volatile phosphorus compounds during incineration. Inputs of chlorinated OPFRs did not affect the formation markedly. Destruction and emission behaviors of unintentional POPs were investigated. Emissions of such POPs in exhaust gases and the ash were lower than the Japanese and international standards. Results show that even in wastes with high contents of chlorinated and non-halogenated OPFRs, waste incineration by the current regulations for the waste incinerators can control environmental emissions of OPFRs and unintentional POPs. Incineration is regarded as a best available technology (BAT) for waste management systems. Copyright © 2014 Elsevier B.V. All rights reserved.

Polychlorinated dioxins, furans (PCDD/Fs), dioxin-like polychlorinated biphenyls (dl-PCBs) and indicator PCBs (ind-PCBs) in egg and egg products in Turkey.

PubMed

Olanca, Burcu; Cakirogullari, Gul Celik; Ucar, Yunus; Kirisik, Dursun; Kilic, Devrim

2014-01-01

The aim of the study is to determine concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and indicator PCBs (ind-PCBs) in eggs from cage hens without soil contact, pasteurized egg samples and imported egg yolk powder samples in Turkey. Concentrations of PCDD/Fs, PCDD/Fs and dl-PCBs, and ind-PCBs in eggs and pasteurized egg samples are in the range of 0.247-1.527 pg WHO-TEQ(2005)g(-1) fat, 0.282-1.762 pg WHO-TEQ(2005)g(-1) fat and 202-1,235 pg g(-1) fat, respectively. For egg yolk powder samples, concentrations of PCDD/Fs, PCDD/Fs and dl-PCBs, and ind-PCBs are in the range of 0.122-0.494 pg WHO-TEQ(2005)g(-1) fat, 0.214-0.640 pg WHO-TEQ(2005)g(-1) fat and 217-1,498 pg g(-1) fat, respectively. All results for PCDD/Fs, PCDD/Fs and dl-PCBs, and ind-PCBs are below the values of 2.5 pg WHO-TEQ(2005)g(-1) fat, 5.0 pg WHO-TEQ(2005)g(-1) fat and 40 ng g(-1) fat imposed in Turkish Regulation for eggs and egg products, respectively. In all samples 2,3,4,7,8-PeCDF, 2,3,7,8-TCDD, 1,2,3,7,8-PeCDD and PCB126 are the most prominent congeners. Mean estimated daily exposure to PCDD/Fs and dl-PCBs for Turkish population from egg is 0.011 pg WHO-TEQ(2005)d(-1)kg body weight (bw)(-1). Although the exposure levels are below the TDI of 2 pg WHO-TEQ(1998)kg bw(-1), the results were based only on consumption of egg. In order to estimate total dietary intake for Turkish population, various food items should be investigated. Copyright © 2013 Elsevier Ltd. All rights reserved.

EDGARv4 Gridded Anthropogenic Emissions of Persistent Organic Pollutants (POPs) from Power Generation, Residential and Transport Sectors: Regional Trends Analysis in East Asia.

NASA Astrophysics Data System (ADS)

Muntean, M.; Janssens-Maenhout, G.; Guizzardi, D.; Crippa, M.; Schaaf, E.; Olivier, J. G.; Dentener, F. J.

2016-12-01

Persistent organic pollutants (POPs) are toxic substances and so harmful for human health. Mitigation of these emissions are internationally addressed by the Convention on Long-range Transboundary Air Pollution and by the Stockholm Convention. A global insight on POPs emissions evolution is essential since they can be transported long distances, they bio-accumulate and damage the environment. The Emission Database for Global Atmospheric Research (EDGARv4) is currently updated with POPs. We have estimated the global emissions of Polychlorinated biphenyls (PCBs), Polychlorinated dibenzo-p-dioxins (PCDDs), Polychlorinated dibenzofurans (PCDFs), Polycyclic aromatic hydrocarbons (PAHs) (benzo[a]pyrene (BaP), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), Indeno[1,2,3-cd]pyrene (IcdP)) and Hexachlorobenzene (HCB) from fuel combustion in the power generation, residential and transport sectors. This emissions inventory has been developed by using as input to the EDGAR technology-based emissions calculation algorithm the fossil fuel consumption data from International Energy Agency (2014) and the emission factors from EMEP/EEA (2013). We provide a complete emission time series for the period 1970-2010 and discuss the trends. A comprehensive analysis of the contribution of East Asia region to the total global will be provided for each substance of the POPs group. An example is presented in Figure 1 for BaP emissions from residential sector; with emissions mainly from China, the East Asia region has a great share (32%) in the total global. We distributed the POPs emissions on gridmaps of 0.1°x0.1° resolution. Areas with high emissions in East Asia will be presented and discussed; Figure 2 shows the hot-spots in East Asia for BaP emissions from the residential sector. These emission gridmaps, used as input for the chemical transport models, contribute to the improvement of impact evaluation, which is a key element in measuring the effectiveness of mitigation measures.

Determination of dioxins and polychlorinated biphenyls in breast milk, maternal blood and cord blood from residents of Tohoku, Japan.

PubMed

Nakamura, Tomoyuki; Nakai, Kunihiko; Matsumura, Tohru; Suzuki, Shigeru; Saito, Yoshinori; Satoh, Hiroshi

2008-05-01

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) are bioaccumulative chemicals that are considered to be toxic contaminants based on several epidemiological studies. To elucidate exposure levels of these chemicals in the present study, concentrations of PCDD/DFs, dioxin-like PCBs (DL-PCBs) and PCBs in breast milk, maternal blood and cord blood obtained from the same participants registered in a birth cohort study in Tohoku, Japan, were measured. Congener-specific analysis revealed several differences in minor congeners of these compounds among the three specimen types, although major congeners were detected in the specimens. The toxicity equivalence quantity concentrations (1998 WHO-TEF) and PCBs in breast milk, maternal blood and cord blood on the whole and on a lipid basis were in the order of breast milk > maternal blood > cord blood. Pearson's correlation coefficients of TEQs and total PCBs among the three specimens were high, with the correlation coefficient of TEQ between breast milk and maternal blood being the highest (r=0.94, p<0.001). On the other hand, the TEQ between breast milk and cord blood was the lowest (r=0.79, p<0.001). Pearson's correlation coefficient between the TEQ and PCBs in each specimen was also high (r=0.82-0.95, p<0.001). The associations of chemical concentrations with maternal age, parity, fish intake, BMI and the rate of body weight increase during pregnancy were analyzed with multiple linear regression analysis. TEQ concentrations and PCBs were negatively associated with parity (p<0.05), and maternal age was positively associated with PCBs (p<0.05). However, the associations with BMI and fish intake during pregnancy were not significant. These results suggest that parity is an important factor affecting the concentrations of dioxins and PCBs in these specimens.

Study of PCDD/Fs distribution in fly ash, ash deposits, and bottom ash from a medical waste incinerator in China.

PubMed

Du, Yingzhe; Jin, Yuqi; Lu, Shengyong; Peng, Zheng; Li, Xiaodong; Yan, Jianhua

2013-02-01

Over the past decades in China, the number of medical waste incinerators (MWIs) has been rising rapidly, causing emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). In this study, samples of fly ash, ash deposits, and bottom ash from typical MWIs were analyzed for PCDD/Fs and their distribution characteristics. Results showed international toxic equivalent (I-TEQ) values in the range of 6.9-67 ng I-TEQ/g in fly ash and ash deposits, whereas the concentration in bottom ash was extremely low (only 1.33 pg I-TEQ/g), yet the generation of PCDD/Fs was mostly de novo synthesis in fly ash and ash deposits according to the ratio of PCDFs to PCDDs; the major distribution differences of PCDD/Fs in fly ash was manifested by the content of toxic furan 2,3,7,8-TCDF but other toxic PCDD/Fs showed similar distribution. Other findings are that 2,3,4,7,8-PeCDF had the most contribution to TEQ concentration, and that the most abundant toxic furan congener is 1,2,3,4,6,7,8-HpCDF. Correlation analysis showed that there was no significant correlation between PCDD/Fs concentration and several other physical and chemical parameters. This paper is of interest because it presents the emission performances of PCDD/Fs in ash from medical waste incineration in China. PCDD/F contents in fly ash and ash deposits vary between 6.9 and 67.3 ng I-TEQ/g. However, the concentration in bottom ash was extremely low (only 1.33 x 10(-3) ng I-TEQ/g). The fingerprints of PCDD/Fs in fly ash are almost similar, except for 2,3,7,8-TCDF. There is no marked correlation between PCDD/Fs and other physicochemical properties.

Removal potential of toxic 2378-substituted PCDD/F from incinerator flue gases by waste-derived activated carbons.

PubMed

Hajizadeh, Yaghoub; Onwudili, Jude A; Williams, Paul T

2011-06-01

The application of activated carbons has become a commonly used emission control protocol for the removal or adsorption of persistent organic pollutants from the flue gas streams of waste incinerators. In this study, the 2378-substituted PCDD/F removal efficiency of three types of activated carbons derived from the pyrolysis of refuse derived fuel, textile waste and scrap tyre was investigated and compared with that of a commercial carbon. Experiments were carried out in a laboratory scale fixed-bed reactor under a simulated flue gas at 275°C with a reaction period of four days. The PCDD/F in the solid matrices and exhaust gas, were analyzed using gas chromatography coupled with a triple quadrupole mass spectrometer. In the absence of activated carbon adsorbent, there was a significant increase in the concentration of toxic PCDD/F produced in the reacted flyash, reaching up to 6.6 times higher than in the raw flyash. In addition, there was a substantial release of PCDD/F into the gas phase, which was found in the flue gas trapping system. By application of the different commercial, refuse derived fuel, textile and tyre activated carbons the total PCDD/F toxic equivalent removal efficiencies in the exhaust gas stream were 58%, 57%, 64% and 52%, respectively. In general, the removal of the PCDDs was much higher with an average of 85% compared to PCDFs at 41%. Analysis of the reacted activated carbons showed that there was some formation of PCDD/F, for instance, a total of 60.6 μg I-TEQ kg(-1) toxic PCDD/F was formed in the refuse derived fuel activated carbon compared to 34 μg I-TEQ kg(-1) in the commercial activated carbon. The activated carbons derived from the pyrolysis of waste, therefore, showed good potential as a control material for PCDD/F emissions in waste incinerator flue gases. Copyright © 2011 Elsevier Ltd. All rights reserved.

Contamination of local wildlife following a fire at a polychlorinated biphenyls warehouse in St Basile le Grand, Quebec, Canada.

PubMed

Phaneuf, D; DesGranges, J L; Plante, N; Rodrigue, J

1995-02-01

This study on wildlife contamination, one to ten months after the polychlorinated biphenyls (PCB) fire in St Basile le Grand, Quebec, shows that the fire increased PCB and polychlorinated dibenzofuran (PCDF) levels in animals. From the data, it was not possible to detect a significant increase in polychlorinated dibenzodioxin (PCDD) levels after the fire. Given the relatively small sample size, the differences in concentrations could not be estimated precisely. However, it can be asserted with a 95% confidence level that mean concentrations of total PCBs were roughly 2 to 6 times higher in the area contaminated by the plume of smoke, concentrations of homologues with 3 chlorine atoms were 1 to 4 times higher, and levels of homologues with 5 to 9 chlorine atoms were 3 to 13 times higher. The relative deviations between concentrations in areas under the plume and those outside it were similar for all animals sampled. With regard to total PCDFs, mean concentrations were significantly higher under the smoke plume than outside it for all species. This observation is linked to homologues with 4, 5 and 7 chlorine atoms for which significant differences were detected between the two areas. The fire had no effect on the pattern of PCB congeners found in the tissue of animals in the region. Congeners Nos. 153, 180, 138 and 118 represent approximately 50% of total PCBs. Although PCB and PCDF concentrations were higher in the tissue of local wildlife species exposed to the fire, they were nonetheless comparable to those found in other urban and agricultural areas in Canada. These concentrations, in 2,3,7,8-TCDD toxic equivalents, were much lower than those observed in the wake of three other major incidents involving PCDDs (Elgin, Florida; Times Beach, Missouri; and Seveso, Italy).(ABSTRACT TRUNCATED AT 250 WORDS)

Do PCDD/PCDF standard solutions used in dioxin analysis pose a risk as potentially acutely toxic to lab personnel?

PubMed

Malisch, Rainer; Denison, Michael S; Fiedler, Heidelore; Fürst, Peter; Hoogenboom, Ron L A P; Schaechtele, Alexander; Schrenk, Dieter; van den Berg, Martin

2017-10-01

Laboratory safety requires protecting personnel from chemical exposures. Working with stock solutions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDFs) in routine analysis of feed and food with bioanalytical or physicochemical methods raises some concerns. Since PCDD/PCDFs are considered as possibly acutely toxic, the potential risks were evaluated to determine whether supervision of their use is necessary. Based on LD 50 -data for oral or dermal intake, hazard classification of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as a substance (category 1) and in commercially available TCDD standard solutions (category 4) is different. As worst case exposure scenario during routine laboratory work it was assumed that a dose of 100 ng TCDD gets onto the skin and is absorbed. This would result in the total body burden of a 70 kg person with 15 kg fat increasing from 10 (upper range of current background levels) to ∼17 pg of toxic equivalents (TEQs) of PCDD/PCDFs per g lipid, a level commonly observed over past decades. Chloracne, the main acute effect occurring weeks after exposure, is observed at much higher blood concentrations than estimated from accidental laboratory exposure. Immunotoxicity, developmental effects and other toxic effects may occur at lower blood levels, but require longer periods to develop. Since acute toxic symptoms don't occur within an "8 h acute time window", no supervision is necessary when working with standard solutions in routine analysis. Nevertheless, precautionary measures are needed regarding long-term adverse health effects and appropriate workplace conditions must exist to ensure that additional occupational exposure to PCDD/PCDFs by laboratory personnel is negligible. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preparation of a Bimetal Using Mechanical Alloying for Environmental or Industrial Use

NASA Technical Reports Server (NTRS)

Quinn, Jacqueline; Geiger, Cherie; Clausen, Christian

2013-01-01

Following the 1976 Toxic Substances Control Act ban on their manufacture, PCBs remain an environmental threat. PCBs are known to bio-accumulate and concentrate in fatty tissues. Further complications arise from the potential for contamination of commercial mixtures with other more toxic chlorinated compounds such as polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Until recently, only one option was available for the treatment of PCB-contaminated materials: incineration. This may prove to be more detrimental to the environment than the PCBs themselves due to the potential for formation of PCDDs. Metals have been used for the past ten years for the remediation of halogenated solvents and other contaminants in the environment; however, zero-valent metals alone do not possess the activity required to dehalogenate PCBs. Palladium has been shown to act as an excellent catalyst for the dechlorination of PCBs with active metals. This invention is a method for the production of a palladium/magnesium bimetal capable of dechlorinating PCBs using mechanical milling/mechanical alloying. Other base metals and catalysts may also be alloyed together (e.g., nickel or zinc) to create a similarly functioning catalyst system. Several bimetal catalyst systems currently can be used for processes such as hydrogen peroxide synthesis, oxidation of ethane, selective oxidation, hydrogenation, and production of syngas for further conversion to clean fuels. The processes for making these bimetal catalysts often involve vapor deposition. This technology provides an alternative to vapor deposition that may provide equally active catalysts. A hydrogenation catalyst including a base material coated with a catalytic metal is made using mechanical milling techniques. The hydrogenation catalysts are used as an excellent catalyst for the dehalogenation of contaminated compounds and the remediation of other industrial compounds. The mechanical milling technique is simpler and cheaper than previously used methods for producing hydrogenation catalysts. Preferably, the hydrogenation catalyst is a bimetallic particle formed from a zero-valent iron or zero-valent magnesium particle coated with palladium that is impregnated onto a high-surface-area graphite support. The zero-valent metal particles should be microscale or nanoscale zero-valent magnesium or zero-valent iron particles. Other zero-valent metal particles and combinations may be used. Additionally, the base material may be selected from a variety of minerals including, but not limited to, alumina and zeolites. The catalytic metal is preferably selected from the group consisting of noble metals and transition metals, preferably palladium. The mechanical milling process includes milling the base material with a catalytic metal impregnated into a high-surface-area support to form the hydrogenation catalyst. In a preferred mechanical milling process, a zero-valent metal particle is provided as the base material, preferably having a particle size of less than about 10 microns, preferably 0.1 to 10 microns or smaller, prior to milling. The catalytic metal is supported on a conductive carbon support structure prior to milling. For example, palladium may be impregnated on a graphite support. Other support structures such as semiconductive metal oxides may also be used.

EXPERIMENTAL INVESTIGATION OF PIC FORMATION ...

EPA Pesticide Factsheets

The report gives results of experiments to assess: (1) the effect of residual copper retained in an incineration facility on polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/PCDF) formation during incineration of non-copper-containing chlorofluorocarbons (CFCs); and (2) the formation of chlorinated and aromatic products of incomplete combustion (PICs), including PCDD/PCDFs, during incineration of CFC recycling residue and hydrochlorofluorocarbons (HCFCs). High concentrations of PCDD/PCDFs (23,800 ng/dscm at 7% O2) measured in FY91 during incineration of CFC-12 in a turbulent flame reactor (TFR) could not be repeated in the present study. Repetition tests conducted in the same facility under similar operating conditions resulted in PCDD/PCDF concentrations of 118ng/dscm at 7% O2. However, results of the present study suggest that residual copper retained in an incineration facility possibly promotes the formation of PCDD/PCDFs during incineration of CFC-12 which does not contain copper. Tests conducted in the TFR resulted in measured PCDD/PCDF concentrations of 386-454 ng/dscm at 7% O2 during incineration of CFC-12 which followed incineration of copper-containing compounds. These results suggest that CFCs may best be incinerated in incinerators which do not treat any copper-containing waste prior to CFC incineration. Report available at NTIS as PB96152186. To share information

Cause and motivation in cases of non-fatal drug overdoses in opiate addicts.

PubMed

Pfab, R; Eyer, F; Jetzinger, E; Zilker, Thomas

2006-01-01

Drug overdose (OD) is a frequent incident among opiate addicts. Survivors of ODs are at risk for additional and eventually fatal ODs. ODs may be classified as accidental (aOD) or deliberate (dOD). Investigations into the connection between OD and suicide attempts have led to insconsistent results. (1) to determine how many non-fatal ODs were dODs and how many were aODs; (2) to determine how many cases of dODs were motivated by explicit or by ambivalent suicidal intentions; (3) to determine how many cases of aODs had causes that might respond to preventative measures; (4) to compare the addiction histories of dODs and aODs; (5) to compare the drugs causing the ODs; and (6) to compare the severity of the ODs in both groups. Prospective study utilizing a standardized questionnaire to evaluate opiate-addicted patients admitted to our treatment unit for OD. All cases underwent standardized drug testing to identify drug use patterns. Seventy-four cases of OD underwent standardized interviews after awakening. Forty-three percent of the cases were dOD. Cases of dOD had significantly more OA in substitution programs, more previous ODs, and more often consumed methadone and cocaine. Among dODs, 22.5% had suicidal intention and 9.6% were ambivalent about committing suicide; background motivations were most often conflicts with spouses. Fifty-seven percent of the cases were aOD. Cases of aODs had significantly more potential lethal intoxications and had heroin detected more frequently. aODs happened with unexpected pure heroin (46%), in combination with alcohol (36%), as relapse after abstinence (40%) or after institutionalized treatment (19%). This group should be accessible for targeted education.

Prediction of dioxin/furan incinerator emissions using low-molecular-weight volatile products of incomplete combustion.

PubMed

Lemieux, P M; Lee, C W; Ryan, J V

2000-12-01

Emissions of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) from incinerators and other stationary combustion sources are of environmental concern because of the toxicity of certain PCDD/F congeners. Measurement of trace levels of PCDDs/Fs in combustor emissions is not a trivial matter. Development of one or more simple, easy-to-measure, reliable indicators of stack PCDD/F concentrations not only would enable incinerator operators to economically optimize system performance with respect to PCDD/F emissions, but could also provide a potential technique for demonstrating compliance status on a more frequent basis. This paper focuses on one approach to empirically estimate PCDD/F emissions using easy-to-measure volatile organic C2 chlorinated alkene precursors coupled with flue gas cleaning parameters. Three data sets from pilot-scale incineration experiments were examined for correlations between C2 chlorinated alkenes and PCDDs/Fs. Each data set contained one or more C2 chloroalkenes that were able to account for a statistically significant fraction of the variance in PCDD/F emissions. Variations in the vinyl chloride concentrations were able to account for the variations in the PCDD/F concentrations strongly in two of the three data sets and weakly in one of the data sets.

Prediction of Dioxin/Furan Incinerator Emissions Using Low-Molecular-Weight Volatile Products of Incomplete Combustion.

PubMed

Lemieux, P M; Lee, C W; Ryan, J V

2000-12-01

Emissions of polychlorinated dibenzo-p-dioxins and poly-chlorinated dibenzofurans (PCDDs/Fs) from incinerators and other stationary combustion sources are of environmental concern because of the toxicity of certain PCDD/F congeners. Measurement of trace levels of PCDDs/Fs in combustor emissions is not a trivial matter. Development of one or more simple, easy-to-measure, reliable indicators of stack PCDD/F concentrations not only would enable incinerator operators to economically optimize system performance with respect to PCDD/F emissions, but could also provide a potential technique for demonstrating compliance status on a more frequent basis. This paper focuses on one approach to empirically estimate PCDD/F emissions using easy-to-measure volatile organic C 2 chlorinated alk-ene precursors coupled with flue gas cleaning parameters. Three data sets from pilot-scale incineration experiments were examined for correlations between C 2 chlorinated alk-enes and PCDDs/Fs. Each data set contained one or more C 2 chloroalkenes that were able to account for a statistically significant fraction of the variance in PCDD/F emissions. Variations in the vinyl chloride concentrations were able to account for the variations in the PCDD/F concentrations strongly in two of the three data sets and weakly in one of the data sets.

Dioxin-related compounds in breast milk of women from Vietnamese e-waste recycling sites: levels, toxic equivalents and relevance of non-dietary exposure.

PubMed

Tue, Nguyen Minh; Katsura, Kana; Suzuki, Go; Tuyen, Le Huu; Takasuga, Takumi; Takahashi, Shin; Viet, Pham Hung; Tanabe, Shinsuke

2014-08-01

Although informal e-waste recycling sites (EWRSs) are hotspots of both polychlorinated and polybrominated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs and PBDD/Fs), human exposure to the latter has not been studied in details. This study investigated the accumulation levels and profiles of dioxin-related compounds (DRCs) in breast milk samples from women living in two Vietnamese EWRSs and estimated the intake contribution from e-waste-related exposure. Screening results using Dioxin-Responsive Chemically Activated LUciferase gene eXpression assay (DR-CALUX) showed higher dioxin-like (DL) activities in samples from the EWRS Bui Dau than in those from the EWRS Trang Minh and a reference site (2.3-10 vs 1.7-4.8 and 0.60-5.7 pg CALUX-TEQ/g lipid, n=10, 6 and 9, respectively). Chemical analysis results of selected samples show that the WHO-TEQ levels of PCDD/Fs, DL-PCBs and PBDD/Fs in EWRS samples were not significantly higher than in those from the reference site (0.22-7.4 vs 1.1-3.0 pg/g lipid) and within the Vietnamese background range, but women involved in recycling accumulated higher concentrations of PCDFs (13-15 vs 2.3-8.8 pg/g lipid) and PBDFs (1.1-1.5 vs <1.1 pg/g lipid). By comparing the DRC profile in milk of these women with the reported profile in house dust from the same site, dust ingestion was estimated to contribute most of the intake for tetraBDF, 37 per cent to 55 per cent for penta-octaCDFs, but less than twenty per cent for PCDDs and DL-PCBs, and 26 per cent for total WHO-TEQs. The DL activities in some EWRS milk samples were not fully explained by chemical data, suggesting contribution from unidentified compounds. The estimated WHO-TEQ intake doses for breastfed infants (1.3-33 pg/kg/d) mostly exceeded the tolerable value, especially for those living in the EWRSs; and unidentified DRCs might increase further the dioxin-related health risk. Copyright © 2014 Elsevier Inc. All rights reserved.

Pentachlorophenol from an old henhouse as a dioxin source in eggs and related human exposure.

PubMed

Piskorska-Pliszczynska, Jadwiga; Strucinski, Pawel; Mikolajczyk, Szczepan; Maszewski, Sebastian; Rachubik, Jaroslaw; Pajurek, Marek

2016-01-01

High levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were detected in free-range eggs, and these levels reached a concentration of 29.84 ± 7.45 pg of WHO-TEQ/g of fat. This value exceeded the EU maximum permitted level of 2.5 pg of WHO-TEQ/g of fat for PCDD/F congeners by twelve-fold. A chemical analysis (HRGC-HRMS) revealed elevated amounts of OCDD, OCDF, HxCDD, HpCDD and HpCDF. During the investigation, samples of feed, soil, wall scrapings, wooden ceiling of the henhouse and tissues from laying hens were examined for dioxin contents (30 samples altogether). The long and complicated investigation found that the source of dioxins in the poultry farm was pentachlorophenol-treated wood, which was used as structural components in the 40-year-old farm building adapted to a henhouse. The wooden building material contained PCDD/Fs at a concentration of 3922.60 ± 560.93 pg of WHO-TEQ/g and 11.0 ± 2.8 μg/kg of PCP. The potential risk associated with dioxin intake was characterized by comparing the theoretically calculated weekly and monthly intakes with the toxicological reference values (TRVs), namely the Tolerable Weekly Intake (TWI) and Provisional Tolerable Monthly Intake (PTMI) values of 14 pg of WHO-TEQ/kg of bw and 70 pg of WHO-TEQ/kg of bw, respectively. The intake of dioxins estimated for high egg consumers (approximately 5-6 eggs/week) exceeded the TWI and PTMI values, which may pose a risk of delayed adverse health effects. The estimated dose of PCDD/Fs and DL-PCBs for children consuming 5 eggs per week exceeded the TWI by as much as 450% because of their nearly 5-fold-lower body weight. Although the dioxin intake estimated for the average consumption of eggs in the general population did not exceed any of the TRVs applied (58.7% TWI and 51.1% PTMI), such a situation should be considered unacceptable from a public health perspective because eggs are not the only source of these contaminants. Copyright © 2015 Elsevier Ltd. All rights reserved.

Polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like PCBs in commercialized food products from Colombia.

PubMed

Pemberthy, D; Quintero, A; Martrat, M G; Parera, J; Ábalos, M; Abad, E; Villa, A L

2016-10-15

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) are commonly known as dioxins and are the most toxic members of persistent organic pollutants (POPs) because present a variety of health effects especially as promoting agent of growing and transformation of cancer cells. They are bio-accumulate in humans primarily via the diet, specifically by ingestion of foods that have high lipid content which are generally associated with foods of animal origin such as oils and fats and with fishery and dairy products. In Colombia the Ministry of Health and Social Protection which is the entity responsible for surveillance food conditions, has established maximum levels for dioxins and dl-PCBs in oils from animal and vegetable origins. Oils of vegetable and animal origin represent an appreciable intake in the country thus the presence of dioxins and dl-PCBs in these materials is a matter of concern because they can bioaccumulate in fat. In this contribution the levels of PCDD/Fs and dl-PCBs in olive, soybean, fish oil, butter and shrimp consumed in Colombia were determined using HRGC-HRMS and were compared with the maximum levels permitted in oil samples according to both the Colombian and European regulations. WHO-TEQ concentrations for PCDD/Fs and dioxin like PCBs ranged from 0.24 to 1.710pgWHO-TEQ PCDD/Fg(-1) of fat and from 0.050 to 3.000pgWHO-TEQ PCBg(-1) of fat, respectively. As expected, fish oils and shrimp present the highest WHO-TEQ PCDD/Fs and dl-PCBs values followed by butter and soybean oil sample, while the olive oil shows the lowest levels. In general, the vegetable oils show levels below the limits established by both the Colombian and European regulations. The levels from soybean oil found in this study were slightly higher than the threshold established both by the Commission Regulation European Union (EU) and the Colombian legislation, while fish oils showed concentrations above the European regulations. Furthermore, shrimp exhibited values below the maximum concentration levels established by the EU and Colombian regulation. Copyright © 2016. Published by Elsevier B.V.

Decreased PCDD/F formation when co-firing a waste fuel and biomass in a CFB boiler by addition of sulphates or municipal sewage sludge

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

Åmand, Lars-Erik; Kassman, Håkan, E-mail: hakan.kassman@vattenfall.com

2013-08-15

Highlights: • Two strategies to reduce PCDD/F formation when co-firing solid recovered fuel (SRF) and biomass. • They were co-combustion with municipal sewage sludge (MSS) and addition of ammonium sulphate. • PCDD/Fs were significantly reduced for a biomass rich in chlorine when adding ammonium sulphate. • MSS had a suppressing effect on PCDD/F formation during co-combustion with SRF. • A link is presented between gaseous alkali chlorides, chlorine in deposits and PCDD/F formation. - Abstract: Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are formed during waste incineration and in waste-to-energy boilers. Incomplete combustion, too short residence times at low combustionmore » temperatures (<700 °C), incineration of electronic waste and plastic waste containing chlorine are all factors influencing the formation of PCDD/Fs in boilers. The impact of chlorine and catalysing metals (such as copper and iron) in the fuel on PCDD/F formation was studied in a 12 MW{sub th} circulating fluidised bed (CFB) boiler. The PCDD/F concentrations in the raw gas after the convection pass of the boiler and in the fly ashes were compared. The fuel types were a so-called clean biomass with low content of chlorine, biomass with enhanced content of chlorine from supply of PVC, and solid recovered fuel (SRF) which is a waste fuel containing higher concentrations of both chlorine, and catalysing metals. The PCDD/F formation increased for the biomass with enhanced chlorine content and it was significantly reduced in the raw gas as well as in the fly ashes by injection of ammonium sulphate. A link, the alkali chloride track, is demonstrated between the level of alkali chlorides in the gas phase, the chlorine content in the deposits in the convection pass and finally the PCDD/F formation. The formation of PCDD/Fs was also significantly reduced during co-combustion of SRF with municipal sewage sludge (MSS) compared to when SRF was fired without MSS as additional fuel.« less

Characterisation of transcriptional responses to dioxins and dioxin-like contaminants in roach (Rutilus rutilus) using whole transcriptome analysis.

PubMed

Brinkmann, Markus; Koglin, Sven; Eisner, Bryanna; Wiseman, Steve; Hecker, Markus; Eichbaum, Kathrin; Thalmann, Beat; Buchinger, Sebastian; Reifferscheid, Georg; Hollert, Henner

2016-01-15

There is significant concern regarding the contamination of riverine sediments with dioxins and dioxin-like compounds (DLCs), including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and some polycyclic aromatic hydrocarbons (PAHs). The majority of studies investigating the ecotoxicology of DLCs in fish have focused on a few standard model species. However, there is significant uncertainty as to whether these model species are representative of native river fish, particularly in Europe. In this study, the transcriptional responses following exposure to equipotent concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), PCB 156 or the dioxin-like PAH, benzo[k]fluoranthene (BkF), were investigated in juvenile roach (Rutilus rutilus), a fish species that constitutes a large proportion of the fish biomass in freshwater bodies throughout Europe. To this end, RNA sequencing analysis was used to comprehensively characterise the molecular mechanisms and pathways of toxicity of these DLCs. Whole transcriptome analyses using ClueGO software revealed that DLCs have the potential to disrupt a number of important processes, including energy metabolism, oogenesis, the immune system, apoptosis and the response to oxidative stress. However, despite using equipotent concentrations, there was very little conservation of the transcriptional responses observed in fish exposed to different DLCs. TCDD provoked significant specific changes in the levels of transcripts related to immunotoxicity and carbohydrate metabolism, while PCB 156 caused virtually no specific effects. Exposure to BkF affected the most diverse suite of molecular functions and biological processes, including blood coagulation, oxidative stress responses, unspecific responses to organic or inorganic substances/stimuli, cellular redox homeostasis and specific receptor pathways. To our knowledge, this is the first study of the transcriptome-wide effects of different classes of DLCs in fish. These findings represent an important step towards describing complete toxicity pathways of DLCs, which will be important in the context of informing risk assessments of DLC toxicity in native fish species. Copyright © 2015 Elsevier B.V. All rights reserved.

Characterization of gaseous emissions and ashes from the combustion of furniture waste.

PubMed

Moreno, Ana Isabel; Font, Rafael; Conesa, Juan A

2016-12-01

Gaseous emissions and ash obtained in the combustion of furniture waste have been studied, with particular emphasis on the emissions of hazardous pollutants, such as PCDD/Fs and dl-PCBS. Two different combustion procedures were carried out, one of them in a conventional residential stove (without an automatic control of combustion air and bad mixing of combustion gases with air), and the other in a laboratory-scale reactor (operating under substoichiometric conditions). Three different experiments were carried out in the residential stove, in which the gaseous emissions and ashes obtained were analysed. The fuel burnt out in two of the experiments was furniture wood waste and in one of the experiments, the fuel burnt out was briquettes composed of a mixture of furniture wood with 10wt.% of polyurethane foam. One of the purposes of these experiments was the evaluation of the possible inhibition effect of the higher nitrogen content on the formation of PCDD/Fs. Slight inhibition of the PCDD/F formation was found although, it is noteworthy that the lowest yield of PAHs, volatile and semi-volatile compounds were obtained in the combustion of these briquettes. In all experiments, the emission factors of polychlorinated dibenzo-p-dioxins and dibenzofurans and dioxin-like polychlorinated biphenyls (PCDD/Fs and dl-PCBs) were between 29 and 74ng WHO-TEQ/kg sample burnt, lower than that obtained by other authors in the burning of pine needles and cones. PCDD/Fs and dl-PCBs emissions from furniture wood waste combustion were also analysed in the laboratory scale reactor at 850°C and the results were compared with the values obtained from the combustion of solid wood (untreated wood). The total equivalent toxicity obtained was 21.1ng WHO-TEQ/kg sample for combustion of furniture wood waste, which is low in comparison with those obtained for other waste combustion in similar conditions. In the laboratory scale reactor, PCDFs were the dominant compounds in the profiles of PCDD/Fs, by contrast, in the combustion in the residential stove, the majority compounds were PCDDs, due to the different operation conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of food supply and chlorinated hydrocarbon contaminants on breeding success of bald eagles.

PubMed

Gill, Christopher E; Elliott, John E

2003-01-01

Food supply and contaminants were investigated as possible causes of low bald eagle productivity near a bleached kraft pulp and paper mill at Crofton on Vancouver Island, British Columbia. Over a seven year period, 1992-1998, average productivity of five eagle territories situated south of the pulp mill at Crofton was significantly lower (0.43 young/occupied territory) than six territories north of the mill (1.04 young/occupied territory). A reference population of 32 territories located in Barkley Sound on the west coast of Vancouver Island demonstrated intermediary mean productivity (0.75 young/occupied territory). Measures of prey biomass delivered to nests were lowest south of the mill, and correlated significantly with nesting success. On average, measures of energy delivered to nests and a parameter determined to be related to prey availability, adult nest attendance time, accounted for about 70% of variability in nest success. Contaminant concentrations, including pulp mill derived polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), as well as dichlorodiphenyldichloroethane (DDE), polychlorinated biphenyls (PCBs), and calculated tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) were significantly greater in plasma samples of nestlings from south of the mill compared to the other two sites, but did not correlate significantly with individual nest success data. Nests south of the mill concentrate around Maple Bay, which appears to be a deposition area for contaminants transported by tides and currents from sources such as the pulp mill. Concentrations of DDE and PCBs in plasma of nestling eagles from south of the mill were less than the critical values estimated to affect production of young. For TEQs, there are no published critical values for plasma by which to compare our results. We conclude that less than adequate energy provisioning to nests, presumably related to low prey availability, was likely the main cause of poor nest success south of the mill site at Crofton. However, higher concentrations of both DDE and PCDD/F derived TEQs may have acted in concert with food stress to further reduce bald eagle productivity.

[Epidemiologic studies on the health status of the population living in the Sacco River Valley].

PubMed

Fantini, Fiorella; Porta, Daniela; Fano, Valeria; De Felip, Elena; Senofonte, Oreste; Abballe, Annalisa; D'Ilio, Sonia; Ingelido, Anna Maria; Mataloni, Francesca; Narduzzi, Silvia; Blasetti, Francesco; Forastiere, Francesco

2012-01-01

OBIETTIVO: to analyze the health status of the population living in an area close to the Colleferro industrial plant. the area of the Sacco River Valley, Central Italy nearby Rome, has been heavily polluted over the years by industrial wastes deriving from the chemical industrial plant in Colleferro. In 2006, it was discovered that the herds of livestock were contaminated by beta-hexachlorocycloexane (β-HCH, an industrial waste belonging, as well as lindane, to the group of hexachlorocycloexane isomers). the analyses of mortality and morbidity were carried out for the 1998-2007 period (calculation of standardized mortality ratios, SMR), and for the period 2003-2007 (calculation of standardized hospitalization ratios, SHR), respectively. The general population in the Lazio Region has been considered as reference. In addition, a biomonitoring study was conducted on a sample of the population living in 4 areas of the Sacco River Valley with different levels of exposure and the following persistent organic pollutants were measured in the blood (α, β and γ-HCH, HCB p,p'-DDT and p,p'- DDE, 6 NDL-PCB congeners and 12 DL-PCBs, PCDDs and PCDFs), and heavy metals (Cd, Hg, Pb). cancer mortality in men was increased in the area (SMR=1.20), especially for specific cancer sites (stomach, larynx, lungs, pleura, myeloma); in women an excess of mortality from diabetes was detected (SMR=1.44). The analysis of morbidity indicated an excess of hospitalization for various cancers (larynx, myeloma) in men, for respiratory illness and asthma in both genders and for thyroid disease in women. The biomonitoring study found high mean concentration of β-HCH (mean: 99.05 ng/g fat, SD=121.3), with higher levels in the population living along the river (mean=150 ng/g fat; SD=153.5), likely occurred through water and local food. the area of Colleferro has been polluted by multiple sources and the human population has been exposed to industrial chemicals, toxic substances in the workplace, and to the cumulative accumulation of organic pesticides especially through water and food.

Towards science-based sediment quality standards-Effects of field-collected sediments in rainbow trout (Oncorhynchus mykiss).

PubMed

Brinkmann, Markus; Eichbaum, Kathrin; Reininghaus, Mathias; Koglin, Sven; Kammann, Ulrike; Baumann, Lisa; Segner, Helmut; Zennegg, Markus; Buchinger, Sebastian; Reifferscheid, Georg; Hollert, Henner

2015-09-01

Sediments can act as long-term sinks for environmental pollutants. Within the past decades, dioxin-like compounds (DLCs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) have attracted significant attention in the scientific community. To investigate the time- and concentration-dependent uptake of DLCs and PAHs in rainbow trout (Oncorhynchus mykiss) and their associated toxicological effects, we conducted exposure experiments using suspensions of three field-collected sediments from the rivers Rhine and Elbe, which were chosen to represent different contamination levels. Five serial dilutions of contaminated sediments were tested; these originated from the Prossen and Zollelbe sampling sites (both in the river Elbe, Germany) and from Ehrenbreitstein (Rhine, Germany), with lower levels of contamination. Fish were exposed to suspensions of these dilutions under semi-static conditions for 90 days. Analysis of muscle tissue by high resolution gas chromatography and mass spectrometry and of bile liquid by high-performance liquid chromatography showed that particle-bound PCDD/Fs, PCBs and PAHs were readily bioavailable from re-suspended sediments. Uptake of these contaminants and the associated toxicological effects in fish were largely proportional to their sediment concentrations. The changes in the investigated biomarkers closely reflected the different sediment contamination levels: cytochrome P450 1A mRNA expression and 7-ethoxyresorufin-O-deethylase activity in fish livers responded immediately and with high sensitivity, while increased frequencies of micronuclei and other nuclear aberrations, as well as histopathological and gross pathological lesions, were strong indicators of the potential long-term effects of re-suspension events. Our study clearly demonstrates that sediment re-suspension can lead to accumulation of PCDD/Fs and PCBs in fish, resulting in potentially adverse toxicological effects. For a sound risk assessment within the implementation of the European Water Framework Directive and related legislation, we propose a strong emphasis on sediment-bound contaminants in the context of integrated river basin management plans. Copyright © 2015 Elsevier B.V. All rights reserved.

Atmospheric deposition of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in the Kanto Region, Japan.

PubMed

Ogura, I; Masunaga, S; Nakanishi, J

2001-09-01

The atmospheric bulk (dry and wet) deposition of dioxins was investigated at four locations (Tokyo, Yokohama, Tsukuba, and Tanzawa) in the Kanto region (in Japan) over one year using a stainless-steel pot. Annual average polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/PCDF) deposition fluxes were estimated to be from 450 to 1300 ng/m2/yr, and the annual average TEQ fluxes from 5.7 to 17 ng-TEQ/m2/yr at the four locations. The PCDD/PCDF deposition flux was higher in winter than in summer. The deposition flux could be related to ambient temperature, particularly for less chlorinated PCDDs/PCDFs, while the deposition flux is not necessarily related to the amount of precipitation. The PCDD/PCDF deposition flux increased as the particle deposition flux increased, for the winter samples. Based on the ratio of the PCDD/PCDF deposition fluxes to the particle deposition fluxes, the contribution of the reentrainment of soil particles to the TEQ of PCDD/PCDF deposition was considered to be negligible in this region. Based on the air concentrations monitored near our deposition sampling points by the municipalities, the ratio of the annual deposition flux to the annual average air concentration was roughly estimated to be 0.082 cm/s. The range of deposition flux in the Kanto region was estimated to be from 1.5 to 31 (median: 9.8) ng-TEQ/m2/yr based on the range of air concentration data measured by the municipalities. The total annual deposition flux in the entire Kanto region was estimated to range from 50 to 900 g-TEQ/yr (median 320 g-TEQ/yr). This estimated flux was of the same order as the sum of estimated emissions from municipal solid waste incinerators and industrial waste incinerators in the Kanto region. The contributions of dioxin-like PCBs in Yokohama, Tsukuba, and Tanzawa depositions were less than 10% of the total TEQ; however, in Tokyo it was almost equal to or more than 50%.

Organization Development-What Is It? A Brief Overview.

ERIC Educational Resources Information Center

Hiett, Alyson D.; And Others

1989-01-01

Provides basic knowledge about organizational development (OD). Includes basic strategies of OD; definitions and themes of OD interventions; major types of OD interventions; errors in systems approach to OD; and role of OD consultant. (Author/ABL)

Outcomes Across the Value Chain for a Comprehensive Employee Health and Wellness Intervention: A Cohort Study by Degrees of Health Engagement.

PubMed

Long, D Adam; Reed, Roger W; Duncan, Ian

2016-07-01

Evaluate a large employer's wellness intervention by studying outcomes across the value chain, and testing Health Engagement's (HE) dose-response relationship to outcomes. Evaluation included 37 measures across eight outcomes domains (OD) using repeated measures, analysis of variance and logistic regression. Participants with higher HE had better pre-post percent changes than control: 1.7% higher for Motivation (OD1), 3.4% for Behavior (OD2), 1.0% for Emotion (OD3), 5.8% for Biometrics (OD4), 6.3% for Compliance (OD5), and 5.2% for Claims (OD6). They also had 0.5% less Productivity loss (OD7), and odds of Turnover (OD8) one-quarter to one-half that of control. A dose-response relationship with degrees of HE was also shown. Three outcomes domains (OD6 to OD8) can be monetized for cost-benefit analysis. Authors recommend, however, staying focused on driving HE and using metrics from all OD to assess value.

Organizational Development: The Role of Communication in Diagnosis, Change, and Evaluation.

ERIC Educational Resources Information Center

Hain, Tony; Tubbs, Stewart L.

Three key considerations (What is organizational development (OD)? Why do organizations undertake OD efforts? What are the critical phases (and their pitfalls) that make up the OD effort?) are discussed in this paper. The sections include: "What is OD," which presents three definitions of OD and the goals of OD as identified by Bennis; "Why Do…

Airborne Dioxins, Furans and Polycyclic Aromatic Hydrocarbons Exposure to Military Personnel in Iraq

PubMed Central

Masiol, Mauro; Mallon, Timothy; Haines, Kevin M.; Utell, Mark J.; Hopke, Philip K.

2016-01-01

Objectives The objective was to use ambient polycyclic aromatic hydrocarbon (PAH), polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) concentrations measured at Joint Base Balad in Iraq in 2007 to identify the sources of these species and their spatial patterns. Methods The ratios of the measured species were compared to literature data for likely emission sources. Using the multiple site measurements on specific days, contour maps have been drawn using inverse distance weighting (IDW). Results These analyses suggest multiple sources including the burn pit (primarily a source of PCDD/PCDFs), the transportation field (primarily as source of PAHs) and other sources of PAHs that include aircraft, space heating, and diesel power generation. Conclusions The nature and locations of the sources were identified. PCDD/PCDFs were emitted by the burn pit. Multiple PAH sources exist across the base. PMID:27501100

Remediation of soil contaminated with dioxins by subcritical water extraction.

PubMed

Hashimoto, Shunji; Watanabe, Kiyohiko; Nose, Kazutoshi; Morita, Masatoshi

2004-01-01

The effectiveness of subcritical water extraction (SCWE) was examined for removing dioxins from contaminated soil. Most dioxins in the soil sample were reduced at 300 degrees C or more, but decreased dioxin concentrations were also observed at 150 degrees C. After 4 h of extraction, 99.4%, 94.5% and 60% of PCDDs were removed from samples at 350, 300 and 150 degrees C, respectively. It was also determined that degradation of dioxins had occurred, since the sum of dioxins in the soil plus water extracts after the experiments had considerably decreased. This study revealed that pressurizing is not essential for the removal of dioxins. Reduction was complete within 30 min at 350 degrees C; however, it took a much longer time at lower temperatures. The results of addition experiments in which OCDDs were added to different types of soil samples have shown that dechlorination is one of the major reaction pathways. After addition of OCDD to soil samples, experiments were carried out to examine in detail the degradation pathways of PCDDs. The removal rates and congener profiles varied among soil types. Although it was previously assumed that removal rates and congener profiles depended on the chemical components in soil, nonparametric statistical analysis revealed no significant relationship between the rate of reduction and elements present in the soil. It was confirmed from isomer patterns that dechlorination of the 2,3,7,8-positions in PCDDs takes place somewhat faster than for the 1,4,6,9-positions.

Impact of estuarine gradients on reductive dechlorination of 1,2,3,4-tetrachlorodibenzo-p-dioxin in river sediment enrichment cultures.

PubMed

Dam, Hang T; Häggblom, Max M

2017-02-01

Polychlorinated dibenzo-p-dioxins (PCDDs) are among the most persistent organic pollutants. Although the total input of PCDDs into the environment has decreased substantially over the past four decades, their input via non-point sources is still increasing, especially in estuarine metropolitan areas. Here we report on the microbially mediated reductive dechlorination of PCDDs in anaerobic enrichment cultures established from sediments collected from five locations along the Hackensack River, NJ and investigate the impacts of sediment physicochemical characteristics on dechlorination activity. Dechlorination of 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-TeCDD) and abundance of Dehalococcoides spp. negatively correlated with salinity and sulfate concentration in sediments used to establish the cultures. 1,2,3,4-TeCDD was dechlorinated to a lesser extent in cultures established from sediments from the tidally influenced estuarine mouth of the river. In cultures established from low salinity sediments, 1,2,3,4-TeCDD was reductively dechlorinated with the accumulation of 2-monochlorodibenzo-p-dioxin as the major product. Sulfate concentrations above 2 mM inhibited 1,2,3,4-TecDD dechlorination activity. Consecutive lateral- and peri- dechlorination took place in enrichment cultures with a minimal accumulation of 2,3-dichlorodibenzo-p-dioxin in active cultures. A Dehalococcoides spp. community was enriched and accounted for up to 64% of Chloroflexi detected in these sediment cultures. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Practice of Organization Development.

ERIC Educational Resources Information Center

Vaill, Peter B.

An article about the men who are doing organization Development (O.D.) work is presented. It is divided into the following sections: (1) The Elements of O.D. Practice; (2) Interrelationships of the Elements of O.D. Practice; (3) Sources of Data on O.D. Practice; (4) The O.D. Practitioner and the Client; (5) The O.D. Practitioner and the Evaluator;…

46 CFR 280.9 - Special rules for last year of ODS agreement.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Special rules for last year of ODS agreement. 280.9... LINER OPERATORS § 280.9 Special rules for last year of ODS agreement. (a) Reduction in payment of ODS. ODS payable during the last year of any ODS agreement shall be reduced, as provided in paragraph (b...

Effects of combustion and operating conditions on PCDD/PCDF emissions from power boilers burning salt-laden wood waste.

PubMed

Leclerc, Denys; Duo, Wen Li; Vessey, Michelle

2006-04-01

This paper discusses the effects of combustion conditions on PCDD/PCDF emissions from pulp and paper power boilers burning salt-laden wood waste. We found no correlation between PCDD/PCDF emissions and carbon monoxide emissions. A good correlation was, however, observed between PCDD/PCDF emissions and the concentration of stack polynuclear aromatic hydrocarbons (PAHs) in the absence of TDF addition. Thus, poor combustion conditions responsible for the formation of products of incomplete combustion (PICs), such as PAHs and PCDD/PCDF precursors, increase PCDD/PCDF emissions. PAH concentrations increased with higher boiler load and/or low oxygen concentrations at the boiler exit, probably because of lower available residence times and insufficient excess air. Our findings are consistent with the current understanding that high ash carbon content generally favours heterogeneous reactions leading to either de novo synthesis of PCDD/PCDFs or their direct formation from precursors. We also found that, in grate-fired boilers, a linear increase in the grate/lower furnace temperature produces an exponential decrease in PCDD/PCDF emissions. Although the extent of this effect appears to be mill-specific, particularly at low temperatures, the results indicate that increasing the combustion temperature may decrease PCDD/PCDF emissions. It must be noted, however, that there are other variables, such as elevated ESP and stack temperatures, a high hog salt content, the presence of large amounts of PICs and a high Cl/S ratio, which contribute to higher PCDD/PCDFs emissions. Therefore, higher combustion temperatures, by themselves, will not necessarily result in low PCDD/PCDFs emissions.

Effects of Zr Addition on Strengthening Mechanisms of Al-Alloyed High-Cr ODS Steels.

PubMed

Ren, Jian; Yu, Liming; Liu, Yongchang; Liu, Chenxi; Li, Huijun; Wu, Jiefeng

2018-01-12

Oxide dispersion strengthened (ODS) steels with different contents of zirconium (denoted as 16Cr ODS, 16Cr-0.3Zr ODS and 16Cr-0.6Zr ODS) were fabricated to investigate the effects of Zr on strengthening mechanism of Al-alloyed 16Cr ODS steel. Electron backscatter diffraction (EBSD) results show that the mean grain size of ODS steels could be decreased by Zr addition. Transmission electron microscope (TEM) results indicate that Zr addition could increase the number density but decrease the mean diameter and inter-particle spacing of oxide particles. Furthermore, it is also found that in addition to Y-Al-O nanoparticles, Y-Zr-O oxides with finer size were observed in 16Cr-0.3Zr ODS and 16Cr-0.6Zr ODS steels. These changes in microstructure significantly increase the yield strength (YS) and ultimate tensile strength (UTS) of ODS steels through mechanisms of grain boundary strengthening and dispersion strengthening.

Effects of Zr Addition on Strengthening Mechanisms of Al-Alloyed High-Cr ODS Steels

PubMed Central

Ren, Jian; Yu, Liming; Liu, Yongchang; Liu, Chenxi; Li, Huijun; Wu, Jiefeng

2018-01-01

Oxide dispersion strengthened (ODS) steels with different contents of zirconium (denoted as 16Cr ODS, 16Cr-0.3Zr ODS and 16Cr-0.6Zr ODS) were fabricated to investigate the effects of Zr on strengthening mechanism of Al-alloyed 16Cr ODS steel. Electron backscatter diffraction (EBSD) results show that the mean grain size of ODS steels could be decreased by Zr addition. Transmission electron microscope (TEM) results indicate that Zr addition could increase the number density but decrease the mean diameter and inter-particle spacing of oxide particles. Furthermore, it is also found that in addition to Y-Al-O nanoparticles, Y-Zr-O oxides with finer size were observed in 16Cr-0.3Zr ODS and 16Cr-0.6Zr ODS steels. These changes in microstructure significantly increase the yield strength (YS) and ultimate tensile strength (UTS) of ODS steels through mechanisms of grain boundary strengthening and dispersion strengthening. PMID:29329260

Organization Development Strategies in Educational Policy Planning and Management.

ERIC Educational Resources Information Center

Jones, B. Kathryn; Biles, Stephen

1990-01-01

This synthesis reviews organizational development (OD) and its decision tools, describes OD applications in educational organizations, explores OD's limitations, and predicts how OD will influence future educational decision making. Findings identify eight specific management and planning areas where OD can be used to improve organizational…

Automatic optic disc segmentation based on image brightness and contrast

NASA Astrophysics Data System (ADS)

Lu, Shijian; Liu, Jiang; Lim, Joo Hwee; Zhang, Zhuo; Tan, Ngan Meng; Wong, Wing Kee; Li, Huiqi; Wong, Tien Yin

2010-03-01

Untreated glaucoma leads to permanent damage of the optic nerve and resultant visual field loss, which can progress to blindness. As glaucoma often produces additional pathological cupping of the optic disc (OD), cupdisc- ratio is one measure that is widely used for glaucoma diagnosis. This paper presents an OD localization method that automatically segments the OD and so can be applied for the cup-disc-ratio based glaucoma diagnosis. The proposed OD segmentation method is based on the observations that the OD is normally much brighter and at the same time have a smoother texture characteristics compared with other regions within retinal images. Given a retinal image we first capture the ODs smooth texture characteristic by a contrast image that is constructed based on the local maximum and minimum pixel lightness within a small neighborhood window. The centre of the OD can then be determined according to the density of the candidate OD pixels that are detected by retinal image pixels of the lowest contrast. After that, an OD region is approximately determined by a pair of morphological operations and the OD boundary is finally determined by an ellipse that is fitted by the convex hull of the detected OD region. Experiments over 71 retinal images of different qualities show that the OD region overlapping reaches up to 90.37% according to the OD boundary ellipses determined by our proposed method and the one manually plotted by an ophthalmologist.

Changing epidemiology of intentional antidepressant drug overdose in Victoria, Australia.

PubMed

Wong, Anselm; Taylor, David McD; Ashby, Karen; Robinson, Jeff

2010-08-01

To determine the epidemiology of intentional antidepressant drug overdose (OD), over an extended time period, in Victoria, Australia. Retrospective epidemiological study of all cases reported to the Victorian Emergency Minimum Dataset (VEMD) January 1998 to December 2007 and calls to the Victorian Poisons Information Centre (VPIC) June 2005 to September 2008. 5467 VEMD cases were analysed. 3169 (57.9%) cases involved selective serotonin reuptake inhibitors (SSRIs) and 1149 (21%) involved tricyclic antidepressants (TCAs). Sertraline (1252, 22.9% cases) was the most common drug. During 2001, the peak year of OD, there were 8.8 OD/100 000 population in the SSRI group and 3.8 OD/100 000 population in the TCA group. Trends over the study period showed increasing SSRI and 'other' newer antidepressant prescription rates and decreases for TCA and monoamine oxidase inhibitors (MAOI). However, the risks of OD in all drug classes were similar and OD/100 000 prescriptions trended downwards for all drug classes over time. 1833 VPIC calls were analysed. Calls relating to SSRIs were the most common yet SSRI OD was associated with significantly fewer symptoms (p < 0.001) and fewer patients with Poisoning Severity Score classifications of moderate or severe (p < 0.01). Antidepressant OD patterns are changing. Antidepressant OD incidence is following prescribing trends. The risk of OD is similar for all drug classes. Absolute numbers of OD and OD/100 000 prescriptions are decreasing for all drug classes.

EMISSIONS OF METALS, CHROMIUM AND NICKEL SPECIES, AND ORGANICS FROM MUNICIPAL WASTEWATER SLUDGE INCINERATORS

EPA Science Inventory

In order to provide data to support regulations on municipal wastewater sludge incineration, emissions of metals, hexavalent chromium, nickel subsulfide, polychlorinated dibenzo-dioxins and furans (PCDD/PCDFs), semivolatile and volatile organic compounds, carbon monoxide (CO)...

TRANSIENT PCDD AND PCDF CONCENTRATIONS IN A MWC

EPA Science Inventory

Time-resolved evaluations of combustor performance have shown that concentrations of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) and related pollutants undergo significant changes as a response to upset combustion conditions. During and after tr...

46 CFR 282.20 - Amount of subsidy payable.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Rates. Daily ODS rates shall be used to quantify the amount of ODS payable. The daily ODS rate... items is the daily amount of ODS payable for approved vessel operating days, excluding reduced crew... the daily wage ODS rate to conform to the complement remaining on the vessel. The man-day reduction...

EU marketing authorization review of orphan and non-orphan drugs does not differ.

PubMed

Putzeist, M; Mantel-Teeuwisse, A K; Llinares, J; Gispen-De Wied, C C; Hoes, A W; Leufkens, H G M

2013-10-01

Marketing authorization application dossiers of 17 orphan drugs (ODs) and 51 non-ODs evaluated by the European Medicines Agency (EMA) in the period 2009-2010 were compared. We aimed to identify whether any differences existed between ODs and non-ODs in number and type of deficits brought forward during the EMA review, regarding the clinical development plan, clinical outcome and medical need and studied whether these deficits were similarly associated with marketing approval in the EU. In 71% of the ODs dossiers and 65% of the non-ODs dossiers marketing approval was granted. Differences in deficits were found, but similarities in the way ODs and non-ODs were reviewed and marketing approval decisions were taken, underline that regulatory standards are equally high. Copyright © 2013 Elsevier Ltd. All rights reserved.

Radiation response of ODS ferritic steels with different oxide particles under ion-irradiation at 550 °C

NASA Astrophysics Data System (ADS)

Song, Peng; Morrall, Daniel; Zhang, Zhexian; Yabuuchi, Kiyohiro; Kimura, Akihiko

2018-04-01

In order to investigate the effects of oxide particles on radiation response such as hardness change and microstructural evolution, three types of oxide dispersion strengthened (ODS) ferritic steels (named Y-Ti-ODS, Y-Al-ODS and Y-Al-Zr-ODS), mostly strengthened by Y-Ti-O, Y-Al-O and Y-Zr-O dispersoids, respectively, were simultaneously irradiated with iron and helium ions at 550 °C up to a damage of 30 dpa and a corresponding helium (He) concentration of ∼3500 appm to a depth of 1000-1300 nm. A single iron ion beam irradiation was also performed for reference. Transmission electron microscopy revealed that after the dual ion irradiation helium bubbles of 2.8, 6.6 and 4.5 nm in mean diameter with the corresponding number densities of 1.1 × 1023, 2.7 × 1022 and 3.6 × 1022 m-3 were observed in Y-Ti-ODS, Y-Al-ODS and Y-Al-Zr-ODS, respectively, while no such bubbles were observed after single ion irradiation. About 80% of intragranular He bubbles were adjacent to oxide particles in the ODS ferritic steels. Although the high number density He bubbles were observed in the ODS steels, the void swelling in Y-Ti-ODS, Y-Al-ODS and Y-Al-Zr-ODS was still small and estimated to be 0.13%, 0.53% and 0.20%, respectively. The excellent swelling resistance is dominantly attributed to the high sink strength of oxide particles that depends on the morphology of particle dispersion rather than the crystal structure of the particles. In contrast, no dislocation loops were produced in any of the irradiated steels. Nanoindentation measurements showed that no irradiation hardening but softening was found in the ODS ferritic steels, which was probably due to irradiation induced dislocation recovery. The helium bubbles in high number density never contributed to the irradiation hardening of the ODS steels at these irradiation conditions.

Creep and tensile properties of several oxide-dispersion-strengthened nickel-base alloys at 1365 K

NASA Technical Reports Server (NTRS)

Wittenberger, J. D.

1977-01-01

The tensile properties at room temperature and at 1365 K and the tensile creep properties at low strain rates at 1365 K were measured for several oxide-dispersion-strengthened (ODS) alloys. The alloys examined included ODS Ni, ODS Ni-20Cr, and ODS Ni-16Cr-Al. Metallography of creep tested, large grain size ODS alloys indicated that creep of these alloys is an inhomogeneous process. All alloys appear to possess a threshold stress for creep. This threshold stress is believed to be associated with diffusional creep in the large grain size ODS alloys and normal dislocation motion in perfect single crystal (without transverse low angle boundaries) ODS alloys. Threshold stresses for large grain size ODS Ni-20Cr and Ni-16Cr-Al type alloys are dependent on the grain aspect ratio. Because of the deleterious effect of prior creep on room temperature mechanical properties of large grain size ODS alloys, it is speculated that the threshold stress may be the design limiting creep strength property.

Recent status of organohalogens, heavy metals and PAHs pollution in specific locations in India.

PubMed

Subramanian, Annamalai; Kunisue, Tatsuya; Tanabe, Shinsuke

2015-10-01

Our group of scientists at the Center for Marine Environmental Studies (CMES), Ehime University, Japan has been carrying-out studies in India from the 1980s on chemicals contamination. Due to its agrarian economy, use of fossil fuels, industries, growing population and urbanization, chemicals such as pesticides, dioxins and related chemicals (DRCs), brominated flame retardants (BFRs), heavy metals, and polyaromatic hydrocarbons (PAHs) are widely spread in India. We have published a review (Subramanian and Tanabe, 2007) covering papers published until 2005, on India. A decade had passed and this is the time to provide an update of the spatial and temporal changes during this period and hence this review. At many instances organochlorines such as DDTs and HCHs showed decreasing trends even though they are still at considerable levels. Novel chemicals such as PCDDs/Fs are seen at municipal solid waste dumping sites of India at levels equivalent to similar locations of the developed world. In the e-waste processing sites in India, especially the informal ones, apart from PCDDs/Fs, some brominated flame retardants (BFRs) and heavy metals were present as contaminants. Metro cities of India showed location specific contamination by HCHs, DDTs, PCDDs/Fs, BFRs, PAHs, etc. Coastal regions of India seem to be still unpolluted when compared to the nearby inland locations. This review is concerned mainly with the chemicals that we (CMES) have been evaluating in India in the past three decades. We suggest the importance of further studies, future directions for policy decisions and also for implementing control measures. Copyright © 2015 Elsevier Ltd. All rights reserved.

Perinatal dioxin exposure and the neurodevelopment of Vietnamese toddlers at 1 year of age.

PubMed

Pham, Tai The; Nishijo, Muneko; Nguyen, Anh Thi Nguyet; Tran, Nghi Ngoc; Hoang, Luong Van; Tran, Anh Hai; Nguyen, Trung Viet; Nishijo, Hisao

2015-12-01

Dioxin concentrations remain elevated in both the environment and in humans residing near former US Air Force bases in South Vietnam. This may potentially have adverse health effects, particularly on infant neurodevelopment. We followed 214 infants whose mothers resided in a dioxin-contaminated area in Da Nang, Vietnam, from birth until 1 year of age. Perinatal exposure to dioxins was estimated from toxic equivalent (TEQ) levels of polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/Fs-TEQ), and 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TetraCDD) concentrations in breast milk. In infants, daily dioxin intake (DDI) was used as an index of postnatal exposure through breastfeeding. Neurodevelopment of toddlers was assessed using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III). No significant differences in neurodevelopmental scores were exhibited for cognitive, language or motor functions between four exposure groups of PCDDs/Fs-TEQ or 2,3,7,8-TetraCDD. However, social-emotional scores were decreased in the high PCDDs/Fs-TEQ group and the high 2,3,7,8-TetraCDD group compared with those with mild exposure, after adjusting for confounding factors. Cognitive scores in the mild, moderate, and high DDI groups were significantly higher than those in low DDI group, but there were no differences in cognitive scores among the three higher DDI groups. These results suggest that perinatal exposure to dioxins may affect social-emotional development of 1-year-old toddlers, without diminishing global neurodevelopmental function. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

ANAEROBIC MICROBIAL REDUCTIVE DEBROMINATION OF POLYBROMINATED DIPHENYL ETHERS

EPA Science Inventory

Polybrominated diphenyl ether (PBDE) flame retardants have been detected in sediments, sewage sludge, fish, mammals (including humans), and air throughout the northern hemisphere. While concentrations of PCBs, DDT, and PCDDs in biota are generally decreasing, PBDE concentratio...

CHANGES IN GENE EXPRESSION PROFILE FOLLOWING SHORT-TERM EXPOSURE TO AN ENVIRONMENTALLY RELEVANT MIXTURE OF PHAHS

EPA Science Inventory

Changes in gene expression profile following short-term exposure to an environmentally relevant mixture of PHAHs
Polyhalogenated aromatic hydrocarbons (PHAH) including, polychlorinated biphenyls (PCBs), polychlorinated dibenzodioxins (PCDDS) and polychlorinated dibenzofurans...

UNDERSTANDING PCDD/F FORMATION AND SOURCES

EPA Science Inventory

Recent work at the U. S. EPA has examined fundamental concepts regarding formation and minimization of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/Fs) in combustion scenarios. This paper summarizes some of these main findings, drawing on work from multiple studies....

Applying OD to the Public Sector

ERIC Educational Resources Information Center

Warrick, D. D.

1976-01-01

Discusses special considerations affecting organizational development (OD) programs in public-sector organizations, presents guidelines for using OD procedures in the public sector, and offers conclusions about the applicability of OD in the public sector. (Author/JG)

SU-E-T-135: Investigation of Commercial-Grade Flatbed Scanners and a Medical- Grade Scanner for Radiochromic EBT Film Dosimetry.

PubMed

Syh, J; Patel, B; Syh, J; Wu, H; Rosen, L; Durci, M; Katz, S; Sibata, C

2012-06-01

To evaluate the characteristics of commercial-grade flatbed scanners and medical-grade scanners for radiochromic EBT film dosimetry. Performance aspects of a Vidar Dosimetry Pro Advantage (Red), Epson 750 Pro, Microtek ArtixScan 1800f, and Microtek ScanMaker 8700 scanner for EBT2 Gafchromic film were evaluated in the categories of repeatability, maximum distinguishable optical density (OD) differentiation, OD variance, and dose curve characteristics. OD step film by Stouffer Industries containing 31 steps ranging from 0.05 to 3.62 OD was used. EBT films were irradiated with dose ranging from 20 to 600 cGy in 6×6 cm 2 field sizes and analyzed 24 hours later using RIT113 and Tomotherapy Film Analyzer software. Scans were performed in transmissive mode, landscape orientation, 16-bit image. The mean and standard deviation Analog to Digital (A/D) scanner value was measured by selecting a 3×3 mm 2 uniform area in the central region of each OD step from a total of 20 scans performed over several weeks. Repeatability was determined from the variance of OD step 0.38. Maximum distinguishable OD was defined as the last OD step whose range of A/D values does not overlap with its neighboring step. Repeatability uncertainty ranged from 0.1% for Vidar to 4% for Epson. Average standard deviation of OD steps ranged from 0.21% for Vidar to 6.4% for ArtixScan 1800f. Maximum distinguishable optical density ranged from 3.38 for Vidar to 1.32 for ScanMaker 8700. A/D range of each OD step corresponds to a dose range. Dose ranges of OD steps varied from 1% for Vidar to 20% for ScanMaker 8700. The Vidar exhibited a dose curve that utilized a broader range of OD values than the other scanners. Vidar exhibited higher maximum distinguishable OD, smaller variance in repeatability, smaller A/D value deviation per OD step, and a shallower dose curve with respect to OD. © 2012 American Association of Physicists in Medicine.

AhR transcriptional activity in serum of Inuits across Greenlandic districts

PubMed Central

Long, Manhai; Deutch, Bente; Bonefeld-Jorgensen, Eva C

2007-01-01

Background Human exposure to lipophilic persistent organic pollutants (POPs) including polychlorinated dibenzo-p-dioxins/furans (PCDDs/PCDFs), polychlorinated biphenyls (PCBs) and organochlorine pesticide is ubiquitous. The individual is exposed to a complex mixture of POPs being life-long beginning during critical developmental windows. Exposure to POPs elicits a number of species- and tissue-specific toxic responses, many of which involve the aryl hydrocarbon receptor (AhR). The aim of this study was to compare the actual level of integrated AhR transcriptional activity in the lipophilic serum fraction containing the actual POP mixture among Inuits from different districts in Greenland, and to evaluate whether the AhR transactivity is correlated to the bio-accumulated POPs and/or lifestyle factors. Methods The study included 357 serum samples from the Greenlandic districts: Nuuk and Sisimiut (South West Coast), Qaanaaq (North Coast) and Tasiilaq (East Coast). The bio-accumulated serum POPs were extracted by ethanol: hexane and clean-up on Florisil columns. Effects of the serum extract on the AhR transactivity was determined using the Hepa 1.12cR mouse hepatoma cell line carrying an AhR-luciferase reporter gene, and the data was evaluated for possible association to the serum levels of 14 PCB congeners, 10 organochlorine pesticide residues and/or lifestyle factors. Results In total 85% of the Inuit samples elicited agonistic AhR transactivity in a district dependent pattern. The median level of the AhR-TCDD equivalent (AhR-TEQ) of the separate genders was similar in the different districts. For the combined data the order of the median AhR-TEQ was Tasiilaq > Nuuk ≥ Sisimiut > Qaanaaq possibly being related to the different composition of POPs. In overall, the AhR transactivity was inversely correlated to the levels of sum POPs, age and/or intake of marine food. Conclusion i) We observed that the proportion of dioxin like (DL) compounds in the POP mixture was the dominating factor affecting the level of serum AhR transcriptional activity even at very high level of non DL-PCBs; ii) The inverse association between the integrated serum AhR transactivity and sum of POPs might be explained by the higher level of compounds antagonizing the AhR function probably due to selective POP bioaccumulation in the food chain. PMID:17956617

Comparative liver accumulation of dioxin-like compounds in sheep and cattle: Possible role of AhR-mediated xenobiotic metabolizing enzymes.

PubMed

Girolami, F; Spalenza, V; Benedetto, A; Manzini, L; Badino, P; Abete, M C; Nebbia, C

2016-11-15

PCDDs, PCDFs, and PCBs are persistent organic pollutants (POPs) that accumulate in animal products and may pose serious health problems. Those able to bind the aryl hydrocarbon receptor (AhR), eliciting a plethora of toxic responses, are defined dioxin-like (DL) compounds, while the remainders are called non-DL (NDL). An EFSA opinion has highlighted the tendency of ovine liver to specifically accumulate DL-compounds to a greater extent than any other farmed ruminant species. To examine the possible role in such an accumulation of xenobiotic metabolizing enzymes (XME) involved in DL-compound biotransformation, liver samples were collected from ewes and cows reared in an area known for low dioxin contamination. A related paper reported that sheep livers had about 5-fold higher DL-compound concentrations than cattle livers, while the content of the six marker NDL-PCBs did not differ between species. Specimens from the same animals were subjected to gene expression analysis for AhR, AhR nuclear translocator (ARNT) and AhR-dependent oxidative and conjugative pathways; XME protein expression and activities were also investigated. Both AhR and ARNT mRNA levels were about 2-fold lower in ovine samples and the same occurred for CYP1A1 and CYP1A2, being approximately 3- and 9-fold less expressed in sheep compared to cattle, while CYP1B1 could be detectable in cattle only. The results of the immunoblotting and catalytic activity (most notably EROD) measurements of the CYP1A family enzymes were in line with the gene expression data. By contrast, phase II enzyme expression and activities in sheep were higher (UGT1A) or similar (GSTA1, NQO1) to those recorded in cattle. The overall low expression of CYP1 family enzymes in the sheep is in line with the observed liver accumulation of DL-compounds and is expected to affect the kinetics and the dynamics of other POPs such as many polycyclic aromatic hydrocarbons, as well as of toxins (e.g. aflatoxins) or drugs (e.g. benzimidazole anthelmintics) known to be metabolized by those enzymes. Copyright © 2016 Elsevier B.V. All rights reserved.

Dioxin compounds in the deep-sea rose shrimp Aristeus antennatus (Risso, 1816) throughout the Mediterranean Sea

NASA Astrophysics Data System (ADS)

Rotllant, Guiomar; Abad, Esteban; Sardà, Francisco; Ábalos, Manuela; Company, Joan B.; Rivera, Josep

2006-12-01

Polychlorodibenzo- p-dioxins (PCDDs) and polychlorodibenzofurans (PCDFs) are among the more toxic anthropogenic contaminants. They are fat-soluble and accumulate in animal tissues. Exposure to PCDD/Fs can cause several endocrine, reproductive and developmental problems in animals, including human beings. Several studies have demonstrated that fish and invertebrates living in association with sediments are exposed to and accumulate contaminants, but to date there have been no studies of PCDD/Fs contamination in deep-sea regions. Specimens of Aristeus antennatus (Risso, 1816) were collected from depths of 600-2500 m at different points in the Mediterranean Sea, from the western basin off the coast of Barcelona to the central basin off the Peloponnesian Peninsula, with otter trawl gear. Amounts of PCDD/Fs were measured in different animal tissues by high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC-HRMS). This is the first study to report the presence of PCDD/Fs in deep-sea organisms dwelling at depths below 600 m. A. antennatus presented levels of PCDD/Fs of the same order of magnitude, or slightly higher, as those found in shallow-water species ( Melicertus kerathurus) with respect to land-generated contamination. This highlights the widespread distribution of these pollutants and the potential threat posed to the biodiversity of fragile and vulnerable ecosystems such as the deep-sea. PCDD/F levels detected in the edible parts (muscle) of the commercial shrimp A. antennatus were clearly below the toxic limit value established by European legislation. Levels followed the trend muscle

The health risk levels of different age groups of residents living in the vicinity of municipal solid waste incinerator posed by PCDD/Fs in atmosphere and soil.

PubMed

Li, Jiafu; Zhang, Ying; Sun, Tingting; Hao, Huawei; Wu, Hao; Wang, Lili; Chen, Yuxing; Xing, Limin; Niu, Zhiguang

2018-08-01

In our study, health risk levels of different age groups of residents living in the vicinity of a municipal solid waste incinerator (MSWI) posed by polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in atmosphere and soil were evaluated. The toxic equivalent concentrations of PCDD/Fs (TEQ) in surrounding atmosphere and soil of studied MSWI were 0.05-0.12 pg I-TEQ Nm -3 and 7.622-15.450 ng I-TEQ kg -1 , respectively. The PCDFs/PCDDs (F/D) values of PCDD/Fs in surrounding atmosphere of studied MSWI ranged from 0.40 to 5.90 with a mean of 1.80, suggesting that the PCDD/Fs mainly came from combustion sources and studied MSWI could be a key source of PCDD/Fs in surrounding atmosphere. The F/D ratios of PCDD/Fs in surrounding soil ranged from 0.18 to 1.81 with a mean of 0.90, suggesting combustion is not the mainly sources of PCDD/Fs in surrounding soil, and studied MSWI may have limited influence on PCDD/Fs in surrounding soil. O8CDD and 2,3,4,7,8-P5CDF could be the total PCDD/Fs and TEQ indicators in surrounding atmosphere of studied MSWI, respectively. The carcinogenic risk (CR) values of PCDD/Fs in surrounding atmosphere and soil for children, teens and adults were 1.24E-06, 9.06E-07 and 4.41E-06, respectively, suggesting that the potential cancer risk occurred but the risk was at acceptable levels for both children and adults (<1.00E-05), and the cancer risk for teens was negligible (<1.00E-06). The non-carcinogenic risk (non-CR) values of three age groups were lower than 1, indicating that no obvious non-carcinogenic effects occurred. Inhalation of air was the largest contributor of health risk (both CR and non-CR) for three age groups. In addition, a comparison of the health risk between PCDD/Fs and other emerging contaminants and traditional pollutants in soil and atmosphere was performed, which will help us have a good view of the health risk levels of PCDD/Fs in surrounding environment of MWSI. Copyright © 2018 Elsevier B.V. All rights reserved.

Assessment of seasonality in exposure to dioxins, furans and dioxin-like PCBs by using long-term food-consumption data.

PubMed

Feinberg, M; Soler, L; Contenot, S; Verger, P

2011-04-01

According to the European Food Safety Authority (EFSA) guidance related to uncertainties in dietary exposure assessment, exposure assessment based on short-term food-consumption surveys, such as 24-h recalls or 2-day records, tend to overestimate long-term exposure because of the assumption that the dietary pattern will be similar day after day over a lifetime. The aim of this study was to make an assessment of dietary exposure to polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), also called 'dioxins' and 'dioxin-like PCBs', using long-term household purchase and consumption survey data collected by TNS-Secodip. Weekly purchases of the major dioxins and dl-PCB vector products of these contaminants were collected for 328 single-person households, who participated at TNS-Secodip consumption surveys from 2003 to 2005 and who were single-person households in order to estimate better their consumption. These data were combined with average contamination levels of food products. Weekly gross average exposure was estimated at 10.2 pg toxic equivalent (WHO TEQ) kg(-1) bw week(-1) (95% confidence interval [9.6, 10.9]). According to the typical shape of the distribution of individual weekly exposures, it is sensible to fit an exponential law to these data. The mean was therefore 12.1 pg WHO TEQ kg(-1) bw week(-1). This value is higher than the arithmetic mean because it better takes into account inter-individual variability. It was estimated that about 20% of persons in this sample were exceeding the current health-based guidance value mainly due to high consumption of seafood and/or dairy products. Thanks to long survey duration (3 years) and the weekly recording of food consumption, it was possible to demonstrate the actual seasonality of dietary exposure to dioxins and dl-PCBs with a maximum between March and September; similar seasonality is observable for fish consumption. Autoregressive integrated moving average (ARIMA) models were adjusted to the time series and it was demonstrated that the number of times the upper limit of confidence intervals exceeds the provisional tolerable weekly intake (PTWI) is about 15 weeks per year on average. Finally, compared with the results obtained from data collected in the short-term surveys (1 week), this study does not suggest that short-term consumption surveys tend to overestimate the long-term exposure.

2,3,7,8-Tetrachlorodibenzo-p-dioxin equivalents in tissues of birds at Green Bay, Wisconsin, USA

USGS Publications Warehouse

Jones, Paul D.; Giesy, John P.; Newsted, John L.; Verbrugge, David A.; Beaver, Donald L.; Ankley, Gerald T.; Tillitt, Donald E.; Lodge, Keith B.; Niemi, Gerald J.

1993-01-01

The environment has become contaminated with complex mixtures of planar, chlorinated hydrocarbons (PCHs) such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and structurally similar compounds. Because the potencies of individual congeners to cause the same adverse effects vary greatly and the relative as well as absolute concentrations of individual PCH vary among samples from different locations, it is difficult to assess the toxic effects of these mixtures on wildlife. These compounds can cause a number of adverse effects, however, because the toxic effects which occur at ecologically-relevant concentrations such as embryo-lethality and birth defects appear to be mediated through the same mechanism, the potency of individual congeners can be reported relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) which is the most toxic congener in the PCH class. The concentations of 2,3,7,8-TCDD Equivalents (TCDD-EQ) were determined in the tissues of aquatic and terrestrial birds of Green Bay, Wisconsin by the H4IIE bioassay system and compared toxic equivalency factors (TEFs) with the concentration predicted by the use of toxic equivalency factors applied to concentrations of PCH, which were determined by instrumental analyses. Concentrations of TCDD-EQ ranged from 0.52 to 440 ng/kg, wet weight. The greatest concentrations occurred in the fish-eating birds. Concentrations of TCDD-EQ, which were determined by the two methods were significantly correlated, but the additive model which used the TEFs with concentrations of measured PCB, PCDD and PCDF congeners underestimated the concentrations of TCDD-EQ measured by the H4IIE bioassay by an average of 57%. This is thought to be due to contributions from un-quantified PCH, which are known to occur in the environment. Of the quantified PCH congeners, PCDD and PCDF contributed a small portion of the TCDD-EQ in the aquatic birds, while most of the TCDD-EQ were due to non-ortho-substituted PCBs. In the terrestrial birds, the proportion of the TCDD-EQ contributed by the PCDD and PCDF was greater.This paper has been reviewed in accord with U.S. Environmental Protection Agency policy. Mention of specific products or trade names does not imply endorsement by the U.S. Government.

Emissions from prescribed burning of agricultural fields in the Pacific Northwest

NASA Astrophysics Data System (ADS)

Holder, A. L.; Gullett, B. K.; Urbanski, S. P.; Elleman, R.; O'Neill, S.; Tabor, D.; Mitchell, W.; Baker, K. R.

2017-10-01

Prescribed burns of winter wheat stubble and Kentucky bluegrass fields in northern Idaho and eastern Washington states (U.S.A.) were sampled using ground-, aerostat-, airplane-, and laboratory-based measurement platforms to determine emission factors, compare methods, and provide a current and comprehensive set of emissions data for air quality models, climate models, and emission inventories. Batch measurements of PM2.5, volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated dibenzodioxins/dibenzofurans (PCDDs/PCDFs), and continuous measurements of black carbon (BC), particle mass by size, CO, CO2, CH4, and aerosol characteristics were taken at ground level, on an aerostat-lofted instrument package, and from an airplane. Biomass samples gathered from the field were burned in a laboratory combustion facility for comparison with these ground and aerial field measurements. Emission factors for PM2.5, organic carbon (OC), CH4, and CO measured in the field study platforms were typically higher than those measured in the laboratory combustion facility. Field data for Kentucky bluegrass suggest that biomass residue loading is directly proportional to the PM2.5 emission factor; no such relationship was found with the limited wheat data. CO2 and BC emissions were higher in laboratory burn tests than in the field, reflecting greater carbon oxidation and flaming combustion conditions. These distinctions between field and laboratory results can be explained by measurements of the modified combustion efficiency (MCE). Higher MCEs were recorded in the laboratory burns than from the airplane platform. These MCE/emission factor trends are supported by 1-2 min grab samples from the ground and aerostat platforms. Emission factors measured here are similar to other studies measuring comparable fuels, pollutants, and combustion conditions. The size distribution of refractory BC (rBC) was single modal with a log-normal shape, which was consistent among fuel types when normalized by total rBC mass. The field and laboratory measurements of the Angstrom exponent (α) and single scattering albedo (ω) exhibit a strong decreasing trend with increasing MCEs in the range of 0.9-0.99. Field measurements of α and ω were consistently higher than laboratory burns, which is likely due to less complete combustion. When VOC emissions are compared with MCE, the results are consistent for both fuel types: emission factors increase as MCE decreases.

Dietary exposure to polychlorinated biphenyls and dioxins from infancy until adulthood: A comparison between breast-feeding, toddler, and long-term exposure.

PubMed Central

Patandin, S; Dagnelie, P C; Mulder, P G; Op de Coul, E; van der Veen, J E; Weisglas-Kuperus, N; Sauer, P J

1999-01-01

Food is the major source for polychlorinated biphenyl (PCB) and dioxin accumulation in the human body. Therefore, investigating food habits from early ages until reproductive age (25 years) is important in order to assess exposure risk for the next generation. The objective of this study was to assess the PCB/dioxin exposure and the relative contribution of different foods to total exposure during preschool age. Particularly, the importance of lactational PCB/dioxin exposure vs. dietary exposure until adulthood was investigated. A cohort of 207 children was studied from birth until preschool age. Based on 3 planar PCBs and 17 2,3,7,8-substituted dibenzo-para-dioxins (PCDDs) and dibenzofurans (PCDFs) measured in breast milk, a model was developed to calculate the cumulative toxic equivalent (TEQ) intake during breast-feeding (0-1 year). In 3. 5-year-old children, daily dietary intake of planar PCB-TEQ and dioxin-TEQ was measured with a validated food questionnaire. Cumulative TEQ intake from 1 to 5 years was estimated using the PCB- and dioxin-TEQ intake measured with the food questionnaire. Cumulative TEQ intake from 6 to 25 years was estimated using national food consumption and contamination data of PCB- and dioxin-TEQ intake. In toddlers, dairy products contributed 43% to PCB-TEQ and 50% to dioxin-TEQ intake. Meat and meat products contributed 14% and 19%, respectively, and processed foods 23% and 15%, respectively. Breast-feeding for 6 months contributed to the cumulative PCB/dioxin TEQ intake until 25 years of age, 12% in boys and 14% in girls. The daily TEQ intake per kilogram body weight is 50 times higher in breast-fed infants and three times higher in toddlers than in adults. Long-term dietary exposure to PCBs and dioxins in men and women is partly due to breast-feeding (12 and 14%, respectively). After weaning, dairy products, processed foods, and meat are major contributors of PCB and dioxin accumulation until reproductive age. Instead of discouraging breast-feeding, maternal transfer of PCBs and dioxins to the next generation must be avoided by enforcement of strict regulations for PCB and dioxin discharge and by reducing consumption of animal products and processed foods in all ages. Images Figure 1 Figure 2 PMID:9872716

Design of a laboratory scale fluidized bed reactor

NASA Astrophysics Data System (ADS)

Wikström, E.; Andersson, P.; Marklund, S.

1998-04-01

The aim of this project was to construct a laboratory scale fluidized bed reactor that simulates the behavior of full scale municipal solid waste combustors. The design of this reactor is thoroughly described. The size of the laboratory scale fluidized bed reactor is 5 kW, which corresponds to a fuel-feeding rate of approximately 1 kg/h. The reactor system consists of four parts: a bed section, a freeboard section, a convector (postcombustion zone), and an air pollution control (APC) device system. The inside diameter of the reactor is 100 mm at the bed section and it widens to 200 mm in diameter in the freeboard section; the total height of the reactor is 1760 mm. The convector part consists of five identical sections; each section is 2700 mm long and has an inside diameter of 44.3 mm. The reactor is flexible regarding the placement and number of sampling ports. At the beginning of the first convector unit and at the end of each unit there are sampling ports for organic micropollutants (OMP). This makes it possible to study the composition of the flue gases at various residence times. Sampling ports for inorganic compounds and particulate matter are also placed in the convector section. All operating parameters, reactor temperatures, concentrations of CO, CO2, O2, SO2, NO, and NO2 are continuously measured and stored at selected intervals for further evaluation. These unique features enable full control over the fuel feed, air flows, and air distribution as well as over the temperature profile. Elaborate details are provided regarding the configuration of the fuel-feeding systems, the fluidized bed, the convector section, and the APC device. This laboratory reactor enables detailed studies of the formation mechanisms of OMP, such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), poly-chlorinated biphenyls (PCBs), and polychlorinated benzenes (PCBzs). With this system formation mechanisms of OMP occurring in both the combustion and postcombustion zones can be studied. Other advantages are memory effect minimization and the reduction of experimental costs compared to full scale combustors. Comparison of the combustion parameters and emission data from this 5 kW laboratory scale reactor with full scale combustors shows good agreement regarding emission levels and PCDD/PCDF congener patterns. This indicates that the important formation and degradation reactions of OMP in the reactor are the same formation mechanisms as in full scale combustors.

Dioxins and PCBs in game animals: Interspecies comparison and related consumer exposure.

PubMed

Warenik-Bany, Malgorzata; Strucinski, Pawel; Piskorska-Pliszczynska, Jadwiga

2016-01-01

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (DL-PCB) and non-dioxin-like polychlorinated biphenyls (NDL-PCB) are ubiquitous, persistent toxic compounds that are highly bioaccumulative in nature. Wild-living animals are vulnerable to the negative impacts of human activity. Dioxins and PCBs enter the animal organisms through foraging. Due to the toxicological threat, much attention is paid to these compounds worldwide. The aim of this study was to determine the dioxin contamination status of three game animal species (red deer, roe deer, and wild boar) and compare the PCDD/F and PCB congener bioaccumulation in the muscles, abdominal fat and liver. The chemical analysis was performed by the isotope dilution technique (IDMS) with high-resolution gas chromatography coupled with high-resolution mass spectrometry (HRGC/HRMS). Dioxins and PCBs were found in specimens collected from all studied species, suggesting the presence of the test compounds in the environment of the animals. The highest concentrations were found in the livers of all animals. The toxic equivalent (TEQ) levels in the muscles, adipose tissue and liver were in the order red deer > roe deer > wild boar. PCDD/Fs were the dominant congeners in TEQ value. For all tested species, the dominant contributors to the total WHO-TEQ were PCB-126, 2,3,4,7,8-PeCDF and 1,2,3,7,8-PeCDD. Among the PCDD/F congeners in the deer tissues, OCDD, OCDF and 2,3,4,7,8-PeCDF were dominant, while in wild boar, OCDD, 1,2,3,4,6,7,8-HpCDD and 1,2,3,4,6,7,8-HpCF occurred in the highest amounts. Among PCBs, PCB-105, 118, 156, 138, 153 and 180 were dominant in all species, but with different levels. The regular consumption of muscle meat from game animals should not cause unacceptable dioxin intake above the Tolerable Weekly Intake (TWI) value for children and adults. However, liver consumption should be avoided, especially by children and pregnant or lactating women. High consumption of contaminated liver may cause dioxin intake at levels up to 300% of TWI for adults and up to 700% TWI for children. Copyright © 2016 Elsevier Ltd. All rights reserved.

EPA's National Dioxin Air Monitoring Network (NDAMN): Design, implementation, and final results

NASA Astrophysics Data System (ADS)

Lorber, Matthew; Ferrario, Joseph; Byrne, Christian

2013-10-01

The U.S. Environmental Protection Agency (U.S. EPA) established the National Dioxin Air Monitoring Network (NDAMN) in June of 1998, and operated it until November of 2004. The objective of NDAMN was to determine background air concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dl-PCBs). NDAMN started with 10 sampling sites, adding more over time until the final count of 34 sites was reached by the beginning of 2003. Samples were taken quarterly, and the final sample count was 685. All samples were measured for 17 PCDD/PCDF congeners, 8 PCDD/PCDF homologue groups, and 7 dl-PCBs (note: 5 additional dl-PCBs were added for samples starting in the summer of 2002; 317 samples had measurements of 12 dl-PCBs). The overall average total toxic equivalent (TEQ) concentration in the United States was 11.2 fg TEQ m-3 with dl-PCBs contributing 0.8 fg TEQ m-3 (7%) to this total. The archetype dioxin and furan background air congener profile was seen in the survey averages and in most individual samples. This archetype profile is characterized by low and similar concentrations for tetra - through hexa PCDD/PCDF congeners, with elevations in four congeners - a hepta dioxin and furan congener, and both octa congeners. Sites were generally categorized as urban (4 sites), rural (23 sites), or remote (7 sites). The average TEQ concentrations over all sites and samples within these categories were: urban = 15.9 fg TEQ m-3, rural = 13.9 fg TEQ m-3, and remote = 1.2 fg TEQ m-3. Rural sites showed elevations during the fall or winter months when compared to the spring or summer months, and the same might be said for urban sites, but the remote sites appear to show little variation over time. The four highest individual moment measurements were 847, 292, 241, and 132 fg TEQ m-3. For the 847 and 292 fg TEQ m-3 samples, the concentrations of all congeners were elevated over their site averages, but for the 241 and 132 fg TEQ m-3 measurements, only the PCDD congeners were elevated while PCDF and dl-PCB concentrations were similar to the site averages.

Multivariate data analysis to characterize gas chromatography columns for dioxin analysis.

PubMed

Do, Lan; Geladi, Paul; Haglund, Peter

2014-06-20

Principal component analysis (PCA) was applied for evaluating the selectivity of 22 GC columns for which complete retention data were available for the 136 tetra- to octa-chlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). Because the hepta- and octa-homologues are easy to separate the PCA was focused on the 128 tetra- to hexa-CDD/Fs. The analysis showed that 21 of the 22 GC columns could be subdivided into four groups with different selectivity. Group I consists of columns with non-polar thermally stable phases (Restek 5Sil MS and Dioxin 2, SGE BPX-DXN, Supelco Equity-5, and Agilent DB-1, DB-5, DB-5ms, VF-5ms, VF-Xms and DB-XLB). Group II includes ionic liquid columns (Supelco SLB-IL61, SLB-IL111 and SLB-IL76) with very high polarity. Group III includes columns with high-percentage phenyl and cyanopropyl phases (Agilent DB-17 and DB-225, Quadrex CPS-1, Supelco SP-2331, and Agilent CP-Sil 88), and Group IV columns with shape selectivity (Dionex SB-Smectic and Restek LC-50, Supelco βDEXcst, Agilent VF-Xms and DB-XLB). Thus, two columns appeared in both Group I and IV (Agilent VF-Xms and DB-XLB). The selectivity of the other column, Agilent DB-210, differs from those of these four groups. Partial least squares (PLS) regression was used to correlate the retention times of the tetra- to hexa-CDD/Fs on the 22 stationary phases with a set of physicochemical and structural descriptors to identify parameters that significantly influence the solute-stationary phase interactions. The most influential physicochemical parameters for the interaction were associated with molecular size (as reflects in the total energy, electron energy, core-core repulsion and standard entropy), solubility (aqueous solubility and n-octanol/water partition coefficient), charge distribution (molecular polarizability and dipolar moment), and reactivity (relative Gibbs free energy); and the most influential structural descriptors were related to these parameters, in particular, size and dipolar moment. Finally, the PCA and PLS analyses were complemented with linear regression analysis to identify the most orthogonal column combinations, which could be used in comprehensive two-dimensional gas chromatography (GC×GC) to enhance PCDD/F separation and congener profiling. Copyright © 2014 Elsevier B.V. All rights reserved.

Estimating the Success of OD Applications.

ERIC Educational Resources Information Center

Golembiewski, Robert T.; And Others

1982-01-01

Organizational development (OD) and its future are discussed. Examines database implications about OD's applications. Reports an effort to transcend the limitations of the literature, based on a very intensive search for OD applications in both business and government contexts. (CT)

Prenatal Vitamins: OK for Women Who Aren't Pregnant?

MedlinePlus

... fact sheet: Folate. Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/Folate-HealthProfessional/. Accessed March 20, ... fact sheet: Iron. Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/Iron-HealthProfessional/. Accessed March ...

POLYCHLORINATED BIPHENYL AND POLYCHLORINATED DIBENZOFURAN BIOMARKERS OF RISK ASSESSMENT IN ADOLESCENT CHILDREN AND THEIR MOTHERS

EPA Science Inventory

This is two cohort comparison study of endocrine and cytochrome P450 family 1 biomarkers for risk assessment of polychlorinalted biphenyls (PCBs)/polychlorinated dibenzofurans (PCDFs) induced developmental toxicities in the human. The subjects will be sexually mature adoles...

AN ISOMER PREDICTION MODEL FOR PCNS, PCDD/FS, AND PCBS FROM MUNICIPAL WASTE INCINERATORS

EPA Science Inventory

Isomer patterns of polychlorinated naphthalenes (PCNs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated biphenyls (PCBs) from municipal waste incinerators (MWIs) were predicted by a model based on dechlorination kinetics from the most-chlorinated species. Successfu...

MECHANISTIC AND SOURCE UNDERSTANDING OF PCDD/F FORMATION

EPA Science Inventory

The paper discusses mechanistic and source understanding of polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) formation. (NOTE: Considerable research effort has been expended over the last 15-plus years to understand how combustion sources result in formation of PCDDs/F...

MECHANISTIC RELATIONSHIPS AMONG PCDDS/FS, PCNS, PAHS, CLPHS, AND CLBZS IN MUNICIPAL WASTE INCINERATION

EPA Science Inventory

An extensive investigation was done to understand polychlorinated dibenzo-p-dioxin and furan (PCDD/F) formation mechanisms and their relationship with other organic compounds. PCDD/F, chlorophenols, chlorobenzenes, polyaromatic hydrocarbons and polychlorinated naphthalenes were ...

High temperature oxidation behavior of ODS steels

NASA Astrophysics Data System (ADS)

Kaito, T.; Narita, T.; Ukai, S.; Matsuda, Y.

2004-08-01

Oxide dispersion strengthened (ODS) steels are being developing for application as advanced fast reactor cladding and fusion blanket materials, in order to allow increased operation temperature. Oxidation testing of ODS steel was conducted under a controlled dry air atmosphere to evaluate the high temperature oxidation behavior. This showed that 9Cr-ODS martensitic steels and 12Cr-ODS ferritic steels have superior high temperature oxidation resistance compared to 11 mass% Cr PNC-FMS and 17 mass% Cr ferritic stainless steel. This high temperature resistance is attributed to earlier formation of the protective α-Cr 2O 3 on the outer surface of ODS steels.

DIOXIN AND FURAN FORMATION ON FLY ASH FROM A MIXTURE OF CHLOROPHENOLS

EPA Science Inventory

To establish the relationship between specific chlorophenol (CP) congener distributions and polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) products this work investigated the formation of PCDDs/Fs from different CP mixtures passed over fly ash under selected reaction ...

Anosmia and olfactory outcomes following paediatric traumatic brain injury.

PubMed

Bakker, Kathleen; Catroppa, Cathy; Anderson, Vicki

2016-01-01

Research into olfactory dysfunction (OD) following paediatric traumatic brain injury (TBI) is limited. The current study investigated the frequency of OD following paediatric TBI and the relationship between OD and injury characteristics including severity, site of impact and cause of injury. It was hypothesized that children with moderate/severe TBI would demonstrate greater OD than those with mild TBI. Thirty-seven children aged 8-16 with TBI were recruited to a prospective longitudinal study at a metropolitan children's hospital. Olfactory assessment, using the University of Pennsylvania Smell Identification Test, was completed at 0-3 months post-injury. Nineteen per cent of participants demonstrated impaired olfaction, while a small number (5%) were anosmic. A significant relationship between OD and severity of injury was found. No other injury variables demonstrated a significant relationship with olfactory outcomes. OD was relatively common in this paediatric TBI cohort and the hypothesized relationship with severity of injury was supported. It is recommended that information about OD after TBI be routinely provided to children and families. Further research is needed in larger cohorts to support the implementation of routine clinical assessment, understand the relationship between OD and other injury characteristics, determine the functional implications of OD and document recovery trajectories.

Organization Development: A Critique

ERIC Educational Resources Information Center

Stephenson, T. E.

1975-01-01

Reviews the literature dealing with organization development (OD) and discusses the predominant concerns and attitudes of OD theorists and practitioners. Suggests that OD might be more aptly named "human development" and argues that OD practitioners generally act as missionaries who feel they must remedy the errors of their clients' behavior. (JG)

Solubility enhancement of dioxins and PCBs by surfactant monomers and micelles quantified with polymer depletion techniques.

PubMed

Schacht, Veronika J; Grant, Sharon C; Escher, Beate I; Hawker, Darryl W; Gaus, Caroline

2016-06-01

Partitioning of super-hydrophobic organic contaminants (SHOCs) to dissolved or colloidal materials such as surfactants can alter their behaviour by enhancing apparent aqueous solubility. Relevant partition constants are, however, challenging to quantify with reasonable accuracy. Partition constants to colloidal surfactants can be measured by introducing a polymer (PDMS) as third phase with known PDMS-water partition constant in combination with the mass balance approach. We quantified partition constants of PCBs and PCDDs (log KOW 5.8-8.3) between water and sodium dodecyl sulphate monomers (KMO) and micelles (KMI). A refined, recently introduced swelling-based polymer loading technique allowed highly precise (4.5-10% RSD) and fast (<24 h) loading of SHOCs into PDMS, and due to the miniaturisation of batch systems equilibrium was reached in <5 days for KMI and <3 weeks for KMO. SHOC losses to experimental surfaces were substantial (8-26%) in monomer solutions, but had a low impact on KMO (0.10-0.16 log units). Log KMO for PCDDs (4.0-5.2) were approximately 2.6 log units lower than respective log KMI, which ranged from 5.2 to 7.0 for PCDDs and 6.6-7.5 for PCBs. The linear relationship between log KMI and log KOW was consistent with more polar and moderately hydrophobic compounds. Apparent solubility increased with increasing hydrophobicity and was highest in micelle solutions. However, this solubility enhancement was also considerable in monomer solutions, up to 200 times for OCDD. Given the pervasive presence of surfactant monomers in typical field scenarios, these data suggest that low surfactant concentrations may be effective long-term facilitators for subsurface transport of SHOCs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Photocatalytic reductive dechlorination of 2-chlorodibenzo-p-dioxin by Pd modified g-C3N4 photocatalysts under UV-vis irradiation: Efficacy, kinetics and mechanism.

PubMed

Ding, Jiafeng; Long, Gaoyuan; Luo, Yang; Sun, Runze; Chen, Mengxia; Li, Yajun; Zhou, Yanfang; Xu, Xinhua; Zhao, Weirong

2018-05-09

Polychlorinated dibenzo-p-dioxins (PCDDs), as a group of notorious anthropogenic environmental toxicants, are arguably ubiquitous in nature. In this study, we investigated the photocatalytic reductive dechlorination of 2-chlorodibenzo-p-dioxin (2-CDD) over Pd/g-C 3 N 4 catalysts under UV-vis irradiation. The g-C 3 N 4 and a series of Pd/g-C 3 N 4 catalysts were prepared by thermal polymerization and mechanical mixing-illumination method and characterized by XRD, TEM, BET, SEM and UV-vis DRS analyses. Among all the samples, the Pd/g-C 3 N 4 (5 wt%) yielded the optimal dechlorination activity with a total 2-CDD conversion of 54% within 4 h, and 76% of those converted 2-CDD were evolved to dibenzo-p-dioxin (DD). The kinetics of dechlorination could be described as pseudo-first-order decay model (R 2  > 0.84). Corresponding rate constants (k) increased from 0.052 to 0.17 h -1 with Pd contents up to 5 wt% and decreased to 0.13 h -1 with a 10 wt% of Pd. The enhanced activities originated from the surface plasmonic resonance (SPR) effect of Pd nanoparticles and the formation of Schottky barrier between Pd and g-C 3 N 4 , which extend the spectrum responsive range and suppress the charge recombination of g-C 3 N 4 . This is the first report on the photocatalytic reductive removal of PCDDs and may provide a new approach for PCDDs pollution control. Copyright © 2018 Elsevier B.V. All rights reserved.

The Orphan Disease Networks

PubMed Central

Zhang, Minlu; Zhu, Cheng; Jacomy, Alexis; Lu, Long J.; Jegga, Anil G.

2011-01-01

The low prevalence rate of orphan diseases (OD) requires special combined efforts to improve diagnosis, prevention, and discovery of novel therapeutic strategies. To identify and investigate relationships based on shared genes or shared functional features, we have conducted a bioinformatic-based global analysis of all orphan diseases with known disease-causing mutant genes. Starting with a bipartite network of known OD and OD-causing mutant genes and using the human protein interactome, we first construct and topologically analyze three networks: the orphan disease network, the orphan disease-causing mutant gene network, and the orphan disease-causing mutant gene interactome. Our results demonstrate that in contrast to the common disease-causing mutant genes that are predominantly nonessential, a majority of orphan disease-causing mutant genes are essential. In confirmation of this finding, we found that OD-causing mutant genes are topologically important in the protein interactome and are ubiquitously expressed. Additionally, functional enrichment analysis of those genes in which mutations cause ODs shows that a majority result in premature death or are lethal in the orthologous mouse gene knockout models. To address the limitations of traditional gene-based disease networks, we also construct and analyze OD networks on the basis of shared enriched features (biological processes, cellular components, pathways, phenotypes, and literature citations). Analyzing these functionally-linked OD networks, we identified several additional OD-OD relations that are both phenotypically similar and phenotypically diverse. Surprisingly, we observed that the wiring of the gene-based and other feature-based OD networks are largely different; this suggests that the relationship between ODs cannot be fully captured by the gene-based network alone. PMID:21664998

46 CFR 282.31 - Subsidy billing procedures.

Code of Federal Regulations, 2010 CFR

2010-10-01

.... (a) Subsidy voucher—(1) Form. Requests for payment of ODS shall be submitted on a public voucher... affidavit. (1) The following schedules shall be used for calculating the amount of ODS payable: Schedule A (Company) ODSA No. ODS Accrued During Fiscal Year 198__ ODS Payable for the Month of Current voucher...

"Organization Development": How It Works, What It's Becoming, Why It Pays Off.

ERIC Educational Resources Information Center

Sears, Woody H.

1979-01-01

Distinguishes between organizational development (OD) and therapy. OD is defined as a mechanism for problem solving in complex socio-technical systems. Describes possible drawbacks and advantages of the OD process. Provides examples of how OD has helped managers and non-managers work together. (CSS)

OD Technology for the Future.

ERIC Educational Resources Information Center

Blake, Robert R.; Mouton, Jane Srygley

1979-01-01

The authors state that organizational development (OD) consultants are reluctant to rely upon instruments because this would diminish their sense of usefulness. They discuss 15 OD issues and conclude that OD instruments must be based on sound principles of behavior and sequenced in a planned way in order to implement organizational change and…

46 CFR 280.3 - Standards governing award of an ODS agreement.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Standards governing award of an ODS agreement. 280.3 Section 280.3 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION REGULATIONS AFFECTING... LINER OPERATORS § 280.3 Standards governing award of an ODS agreement. No ODS agreement, including any...

Ethical Problems in the Practice of Organization Development.

ERIC Educational Resources Information Center

Wooten, Kevin C.; White, Louis P.

1983-01-01

This article discusses forces that affect the professional ethics of organizational development (OD). Both driving forces and restraining forces have influenced the current status of OD ethics. These forces have operated since the emergence of OD itself, and their fluctuating intensity results in the dynamic nature of the OD profession. (SSH)

Intervention and Evaluation: A Proactive Team Approach to OD

ERIC Educational Resources Information Center

Gavin, James F.; McPhail, S. Morton

1978-01-01

A team of change agents initiated an intensive organizational development (OD) program in a nonacademic, service department of a midwestern university. Concluding comments include exploration of the feasibility of substantive OD change in short-term programs, and the possibility of nonlinear relations between OD outcomes and time investments. For…

Concentrations of PCDD/PCDFs and PCBs in spent foundry sands

USDA-ARS?s Scientific Manuscript database

Approximately 10 million tons of spent foundry sand (SFS) are generated in the U.S. each year, and their beneficial use in agricultural and horticultural applications is being considered. Other studies have demonstrated that trace elements are low enough in sands from iron, steel, and aluminum foun...

[Organization development of the public health system].

PubMed

Pfaff, Holger; Klein, Jürgen

2002-05-15

Changes in the German health care system require changes in health care institutions. Organizational development (OD) techniques can help them to cope successfully with their changing environment. OD is defined as a collective process of learning aiming to induce intended organizational change. OD is based on social science methods and conducted by process-oriented consultants. In contrast to techniques of organizational design, OD is characterized by employee participation. One of the most important elements of OD is the so-called "survey-feedback-technique". Five examples illustrate how the survey-feedback-technique can be used to facilitate organisational learning. OD technique supports necessary change in health care organizations. It should be used more frequently.

ORIGIN OF CARBON IN POLYCHLORINATED DIOXINS AND FURANS FORMED DURING SOOTING COMBUSTION

EPA Science Inventory

The paper discusses results of an investigation on the importance of solid- and gas-phase carbon precursors for the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/Fs) during sooting combustion. Experiments were performed in an entrained flow reactor (EFR)...

PCDD/F EMISSIONS FROM BURNING WHEAT AND RICE FIELD RESIDUE

EPA Science Inventory

The paper presents the first known values for emissions of polychlorinated dibenzodioxins and dibenzofurans (PCDDs/Fs) from combustion of agricultural field biomass. Wheat and rice straw stubble collected from two western U.S. states were tested in a field burn simulation to dete...

Determination of PCDDs in spider webs: preliminary studies

NASA Astrophysics Data System (ADS)

Rybak, Justyna; Rutkowski, Radosław

2018-01-01

The application of spider webs for determination of polichlorinated dibenzo-para-dioxins (PCDDs) has been studied for the first time. The aim of the studies was to find out if spider webs are suitable for such examinations as it was proved in the previous research they are excellent indicators of air pollutants. Spiders are ubiquitous, thus collection of samples is easy and non-invasive. Studies were conducted within the city of Wrocław and surroundings, one of the biggest and at the same time heaviest polluted city in Poland. Five research sites have been chosen, where spider webs were collected after 60 days of continuous exposure time. Webs belonging to two genera Tegenaria sylvestris and Tegenaria ferruginea (family Agelenidae) have been chosen as they are large and very dense, thus they are very suitable for such examinations. Webs were found to retain dioxins probably mainly by external exposure. These promising results should be continued and expanded in the future research.

Neurogenic [corrected] and oropharyngeal dysphagia.

PubMed

Rofes, Laia; Clavé, Pere; Ouyang, Ann; Scharitzer, Martina; Pokieser, Peter; Vilardell, Natalia; Ortega, Omar

2013-10-01

Oropharyngeal dysphagia (OD) is a swallowing disorder caused by congenital abnormalities and structural damage and disease-associated damage of the oral cavity, pharynx, and upper esophageal sphincter. Patients with OD lack the protective mechanisms necessary for effective swallowing, exhibiting difficulty controlling food in the mouth and initiating a swallow, leading to choking, coughing, and nasal regurgitation. OD is a major risk factor for malnutrition, dehydration, and aspiration pneumonia. The following on OD includes commentaries on the application of simulation of oropharyngeal transient receptor potential vanilloid 1 (TRPV1) and maneuvers like the Shaker exercise to improve the safety and efficacy of swallow in OD patients; the prevalence of esophageal pathologies in OD patients and the need to evaluate the esophagus, esophagogastric junction, and stomach; and strategies for clinical screening to detect OD and aspiration among high-risk patients and to improve oral health care, maintain nutrition and hydration, and prevent aspiration pneumonia. © 2013 New York Academy of Sciences.

46 CFR 252.41 - Subsidy billing procedures.

Code of Federal Regulations, 2010 CFR

2010-10-01

... for payment of ODS shall be submitted on a public voucher, Standard Forms 1034 and 1034A, which can be... schedules shall be used for calculating the amount of ODS payable: Schedule A (Company) ODSA No. ODS Accrued During Fiscal Year 19__ ODS Payable for the Month of Current voucher Previous voucher Total Total accrued...

46 CFR 252.30 - Amount of subsidy payable.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Subsidy Rates § 252.30 Amount of subsidy payable. (a) Daily rates. Daily ODS rates shall be used to quantify the amount of ODS payable except for the ODS rates applicable to maintenance and repair expenses, as described separately in § 252.32. The daily ODS rate represents the cost differential between the...

Organization Development: Its Nature, Origins, and Prospects.

ERIC Educational Resources Information Center

Bennis, Warren G.

A primer on organization development (OD), this book presents a basic statement for people in organizations and for practitioners and students of OD. Many concrete examples are included. After a definition of OD, the basic conditions which create the need for OD are discussed: rapid change, growth in size, increasing diversity, change in…

Diagnostic Efficiency of Symptoms for Oppositional Defiant Disorder and Attention-Deficit Hyperactivity Disorder.

ERIC Educational Resources Information Center

Waldman, Irwin D.; Lilienfeld, Scott O.

1991-01-01

Examined diagnostic efficiency of symptoms for experimentally diagnosed oppositional defiant disorder (OD) and attention-deficit hyperactivity disorder (ADHD) in 102 elementary-age boys. Findings from teacher ratings revealed that, on average, ADHD symptoms were as useful as OD symptoms as exclusion criteria for OD, whereas OD symptoms were nearly…

Advances in Research on Organization Development: Toward a Beginning

ERIC Educational Resources Information Center

Pate, Larry E.; And Others

1977-01-01

This paper examines 38 research studies that were conducted on various aspects of organization development (OD) technology. The studies are compared along eight dimensions. Problems associated with evaluating OD and the limited amount of OD research are discussed. It is argued that more systematic, longitudinal research on OD is needed. (Author)

Recent advances in orthostatic hypotension presenting orthostatic dizziness or vertigo.

PubMed

Kim, Hyun-Ah; Yi, Hyon-Ah; Lee, Hyung

2015-11-01

Orthostatic hypotension (OH), a proxy for sympathetic adrenergic failure, is the most incapacitating sign of autonomic failure. Orthostatic dizziness (OD) is known to be the most common symptom of OH. However, recent studies have demonstrated that 30-39 % of patients with OH experienced rotatory vertigo during upright posture (i.e., orthostatic vertigo, OV), which challenges the dogma that OH induces dizziness and not vertigo. A recent population-based study on spontaneously occurring OD across a wide age range showed that the one-year and lifetime prevalence of OD was 10.9 and 12.5 %, respectively. Approximately 83 % of patients with OD had at least one abnormal autonomic function test result. So far, 11 subtypes of OD have been proposed according to the pattern of autonomic dysfunction, and generalized autonomic failure of sympathetic adrenergic and parasympathetic cardiovagal functions was the most common type. Four different patterns of OH, such as classic, delayed, early, and transient type have been found in patients with OD. The head-up tilt test and Valsalva maneuver should be performed for a comprehensive evaluation of sympathetic adrenergic failure in patients with OD/OV. This review summarizes current advances in OH presenting OD/OV, with a particular focus on the autonomic dysfunction associated with OD.

Lower mitochondrial proton leak and decreased glutathione redox in primary muscle cells of obese diet-resistant versus diet-sensitive humans.

PubMed

Thrush, A Brianne; Zhang, Rui; Chen, William; Seifert, Erin L; Quizi, Jessica K; McPherson, Ruth; Dent, Robert; Harper, Mary-Ellen

2014-11-01

Weight loss success in response to energy restriction is highly variable. This may be due in part to differences in mitochondrial function and oxidative stress. The objective of the study was to determine whether mitochondrial function, content, and oxidative stress differ in well-matched obese individuals in the upper [obese diet sensitive (ODS)] vs lower quintiles [obese diet resistant (ODR)] for rate of weight loss. Primary myotubes derived from muscle biopsies of individuals identified as ODS or ODR were studied. Compliant ODS and ODR females who completed in the Ottawa Hospital Weight Management Program and identified as ODS and ODR participated in this study. Eleven ODS and nine ODR weight-stable females matched for age, body mass, and body mass index participated in this study. Vastus lateralis muscle biopsies were obtained and processed for muscle satellite cell isolation. Mitochondrial respiration, content, reactive oxygen species, and glutathione redox ratios were measured in the myotubes of ODS and ODR individuals. Mitochondrial proton leak was increased in myotubes of ODS compared with ODR (P < .05). Reduced and oxidized glutathione was decreased in the myotubes of ODR vs ODS (P < .05), indicating a more oxidized glutathione redox state. There were no differences in myotube mitochondrial content, uncoupling protein 3, or adenine nucleotide translocase levels. Lower rate of mitochondrial proton leak in muscle is a cell autonomous phenomenon in ODR vs ODS individuals, and this is associated with a more oxidized glutathione redox state in ODR vs ODS myotubes. The muscle of ODR subjects may thus have a lower capacity to adapt to oxidative stress as compared with ODS.

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

Battum, LJ van; Heukelom, S

Purpose This study investigates the origin of lateral optical density (OD) variation for Gafchromic film (EBT and EBT2) scanned in transmission mode with Epson flatbed scanners (1680 Expression Pro and 10000XL). Effects investigated are: cross talk, optical path length and polarization. Methods Cross talk has been examined with triangular shaped light-transmission sheets with OD ranging from 0 to opaque. Optical path length has been studied with absorptive and reflective OD-filters (OD range 0.2 to 2.0). Dependency on light-polarization on the scanner read out has been investigated using linear polarizer sheets. All experiments have been performed at centre scanner position (normmore » point) and at several lateral scan positions, without and with (un)irradiated EBT-film. Dose values used ranged between 0.2 to 9 Gy, yielding an OD-range between 0.25 to 1.1. Results The lateral OD variation is dose dependent and increases up to 14% at most lateral position for dose up to 9 Gy. Cross talk effect contributes to 0.5% in clinical used OD ranges but equals 2% for extreme high dose gradients. Film induced optical path length will effect the lateral OD variation up to 3% at most lateral points. Light polarization is inherent present in these scanners due to multiple reflection on mirrors. In addition film induced polarization is the most important effect generating the observed lateral OD variation. Both Gafchromic film base and sensitive layer have polarizing capabilities; for the sensitive layer its influence is dose dependent. Conclusions Lateral OD variation origins from optical physics (i.e. polarization and reflection) related to scanner and film construction. Cross talk can be ignored in film dosimetry for clinical used dose values and gradients. Therefore it is recommended to determine the lateral OD variation per film type and scanner.« less

Analysis of filter tuning techniques for sequential orbit determination

NASA Technical Reports Server (NTRS)

Lee, T.; Yee, C.; Oza, D.

1995-01-01

This paper examines filter tuning techniques for a sequential orbit determination (OD) covariance analysis. Recently, there has been a renewed interest in sequential OD, primarily due to the successful flight qualification of the Tracking and Data Relay Satellite System (TDRSS) Onboard Navigation System (TONS) using Doppler data extracted onboard the Extreme Ultraviolet Explorer (EUVE) spacecraft. TONS computes highly accurate orbit solutions onboard the spacecraft in realtime using a sequential filter. As the result of the successful TONS-EUVE flight qualification experiment, the Earth Observing System (EOS) AM-1 Project has selected TONS as the prime navigation system. In addition, sequential OD methods can be used successfully for ground OD. Whether data are processed onboard or on the ground, a sequential OD procedure is generally favored over a batch technique when a realtime automated OD system is desired. Recently, OD covariance analyses were performed for the TONS-EUVE and TONS-EOS missions using the sequential processing options of the Orbit Determination Error Analysis System (ODEAS). ODEAS is the primary covariance analysis system used by the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD). The results of these analyses revealed a high sensitivity of the OD solutions to the state process noise filter tuning parameters. The covariance analysis results show that the state estimate error contributions from measurement-related error sources, especially those due to the random noise and satellite-to-satellite ionospheric refraction correction errors, increase rapidly as the state process noise increases. These results prompted an in-depth investigation of the role of the filter tuning parameters in sequential OD covariance analysis. This paper analyzes how the spacecraft state estimate errors due to dynamic and measurement-related error sources are affected by the process noise level used. This information is then used to establish guidelines for determining optimal filter tuning parameters in a given sequential OD scenario for both covariance analysis and actual OD. Comparisons are also made with corresponding definitive OD results available from the TONS-EUVE analysis.

Nutritional status of older patients with oropharyngeal dysphagia in a chronic versus an acute clinical situation.

PubMed

Carrión, Silvia; Roca, Maria; Costa, Alicia; Arreola, Viridiana; Ortega, Omar; Palomera, Elisabet; Serra-Prat, Mateu; Cabré, Mateu; Clavé, Pere

2017-08-01

Oropharyngeal dysphagia (OD) is a prevalent risk factor for malnutrition (MN) in older patients and both conditions are related to poor outcome. To explore the nutritional status in older patients with OD in a chronic and an acute clinical situation. We examined 95 older (≥70 years) patients with OD associated to chronic neurological diseases or aging, and 23 older patients with OD and acute community-acquired pneumonia (CAP) with videofluoroscopy; and 15 older people without OD. We collected nutritional status, measured with the Mini Nutritional Assessment (MNA ® ), anthropometric measurements, and biochemistry and bioimpedance for body composition. Functional status was assessed with the Barthel index. 1) Taking into consideration patients with OD with chronic conditions, 51.1% presented a MNA ® ≤23.5; 16.7%, sarcopenia and a) reduced visceral and muscular protein compartments and fat compartment; b) muscular weakness c) intracellular water depletion, and d) reduced body weight. Patients with OD and MNA ® ≤23 needed higher levels of nectar viscosity for a safe swallow and had increased oropharyngeal residue at spoon-thick viscosity. 2) Patients with OD and CAP, 69.5%, presented an MNA ® ≤23.5 and 29.4% sarcopenia, the inflammatory response of the pneumonia adding to the more severe depletion in visceral protein and muscular mass. Prevalence of impaired nutritional status (malnutrition risk, and sarcopenia) among older patients with OD associated with either chronic or acute conditions is very high. In patients with OD and chronic diseases, poor nutritional status further impairs OD with an increase in oropharyngeal residue at spoon-thick viscosity. In the acute setting there is inflammation and an additional protein deficiency. These findings will help develop specific products both for OD and nutritional status in each specific clinical situation. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

46 CFR 280.4 - Standards governing payment of ODS.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Standards governing payment of ODS. 280.4 Section 280.4... Standards governing payment of ODS. (a) Full payment. Except to the extent otherwise provided in § 280.8, ODS shall be paid in full to the operator for vessel operations on the inbound and outbound legs of...

46 CFR 282.24 - Protection and indemnity insurance.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Subsidy Per Voyage Day ($27,336,900÷3,500 days)=$7,810.54 Ratio P&I Deductible ODS to Wage ODS $287.85÷$7,810.54=3.69% T.R. 98 ship type Daily wage ODS 1/1/85 Ratio P&I ded. to wage ODS (percent) Daily P&I ded. ODS 1/1/85 C4-A $9,000 ×3.69 $332.10 C5-B 9,300 ×3.69 343.17 C6-C 9,600 ×3.69 354.24 (ii) In...

46 CFR 252.34 - Protection and indemnity insurance.

Code of Federal Regulations, 2010 CFR

2010-10-01

... subsidy per voyage day ($27,336,900÷3,500 days)=$7,810.54. Ratio P&I deductible ODS to wage ODS $287.85÷$7,810.54=3.69%. T.R. 98 ship type Daily wage ODS 1/1/85 Ratio P&I ded. to wage ODS (pct) Daily P&I ded. ODS 1/1/85 C4-A $9,000 ×3.69 $332.10 C5-B 9,300 ×3.69 343.17 C6-C 9,600 ×3.69 354.34 (ii) In cases...

PHOTODEGRADATION OF POLYCHLORINATED DIBENZO-P-DIOXINS (PCDDS) IN VAPORS AND AEROSOLS. (R825549C049)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

PCDD/F, PCB, HXCBZ, PAH, AND PM EMISSION FACTORS FOR FIREPLACE AND WOODSTOVE COMBUSTION IN THE SAN FRANCISCO BAY REGION

EPA Science Inventory

Emissions from residential fireplace and woodstove appliances burning fuels available from the San Francisco Bay area were sampled for polychlornated dibenzodioxins and dibenzofurans (PCDDs/Fs), polychlorinated biphenyls (PCBs), hexachlorobenzene (HxCBz), particulate
matter (P...

SITE DEMONSTRATION OF MINERGY GLASS FURNACE TREATMENT OF PCBS, PCDDS/FS, AND METALS IN RIVER SEDIMENT

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) program selected the Glass Furnace Technology (GFT) treatment process for evaluation. The GFT was developed by Minergy Corporation (Minergy) as an ex situ remediation technolog...

[Relationship between Occlusal Discomfort Syndrome and Occlusal Threshold].

PubMed

Munakata, Motohiro; Ono, Yumie; Hayama, Rika; Kataoka, Kanako; Ikuta, Ryuhei; Tamaki, Katsushi

2016-03-01

Occlusal dysesthesia has been defined as persistent uncomfortable feelings of intercuspal position continuing for more than 6 months without evidence of physical occlusal discrepancy. The problem often occurs after occlusal intervention by dental care. Although various dental treatments (e. g. occlusal adjustment, orthodontic treatment and prosthetic reconstruction) are attempted to solve occlusal dysesthesia, they rarely reach a satisfactory result, neither for patients nor dentists. In Japan, these symptoms are defined by the term "Occlusal discomfort syndrome" (ODS). The aim of this study was to investigate the characteristics of ODS with the simple occlusal sensory perceptive and discriminative test. Twenty-one female dental patients with ODS (mean age 55.8 ± 19.2 years) and 21 age- and gender-matched dental patients without ODS (mean age 53.1 ± 16.8 years) participated in the study. Upon grinding occlusal registration foils that were stacked to different thicknesses, participants reported the thicknesses at which they recognized the foils (recognition threshold) and felt discomfort (discomfort threshold). Although there was no significant difference in occlusal recognition thresholds between the two patient groups, the discomfort threshold was significantly smaller in the patients with ODS than in those without ODS. Moreover, the recognition threshold showed an age-dependent increase in patients without ODS, whereas it remained comparable between the younger (< 60 years old) and elderly (60 years old or more) patient subgroups with ODS. These results suggest that occlusal discomfort threshold rather than recognition threshold is an issue in ODS. The foil grinding procedure is a simple and useful method to evaluate occlusal perceptive and discriminative abilities in patients with ODS.

Diagnosis of occlusal dysesthesia utilizing prefrontal hemodynamic activity with slight occlusal interference.

PubMed

Ono, Yumie; Ishikawa, Yu; Munakata, Motohiro; Shibuya, Tomoaki; Shimada, Atsushi; Miyachi, Hideo; Wake, Hiroyuki; Tamaki, Katsushi

2016-11-01

Clinical diagnosis of occlusal dysesthesia (OD), also referred to as phantom bite syndrome, is currently based on the absence of objective occlusal discrepancy despite the persistent complaint of uncomfortable bite sensation. We previously demonstrated that the subjective feeling of occlusal discomfort generated by artificial occlusal interference can be objectively evaluated using prefrontal hemodynamic activity in young healthy individuals. The aim of this study was to investigate whether dental patients with and without OD show distinct prefrontal activity during grinding behavior with an occlusal interference. Six dental patients with OD (OD group) and eight patients without OD (control group) grinded piled occlusal strips placed between their first molars and reported their perception and discomfort thresholds during continuous monitoring of prefrontal hemodynamic activity with a portable functional near-infrared spectroscopy. Although patients without OD showed the typical hemodynamic pattern of increased oxyhemoglobin and reduced deoxyhemoglobin (HHb) concentration, those with OD showed persistent incremental increases of HHb concentration that began at the loading of occlusal strips on their molars before they executed grinding. The intensities of the task-related HHb activities showed statistically significant differences between OD and control groups, particularly at channel 3, arranged over the left frontal pole cortex. When the discrimination criterion was set using the intensity values of channel 3 from both groups, the overall accuracy of the OD discrimination was 92.9%. Although physiological interpretation has yet to be elucidated, the task-related response of an increase in HHb may be a useful neuronal signature to characterize dental patients with OD.

Diagnosis of occlusal dysesthesia utilizing prefrontal hemodynamic activity with slight occlusal interference

PubMed Central

Ishikawa, Yu; Munakata, Motohiro; Shibuya, Tomoaki; Shimada, Atsushi; Miyachi, Hideo; Wake, Hiroyuki; Tamaki, Katsushi

2016-01-01

Clinical diagnosis of occlusal dysesthesia (OD), also referred to as phantom bite syndrome, is currently based on the absence of objective occlusal discrepancy despite the persistent complaint of uncomfortable bite sensation. We previously demonstrated that the subjective feeling of occlusal discomfort generated by artificial occlusal interference can be objectively evaluated using prefrontal hemodynamic activity in young healthy individuals. The aim of this study was to investigate whether dental patients with and without OD show distinct prefrontal activity during grinding behavior with an occlusal interference. Six dental patients with OD (OD group) and eight patients without OD (control group) grinded piled occlusal strips placed between their first molars and reported their perception and discomfort thresholds during continuous monitoring of prefrontal hemodynamic activity with a portable functional near‐infrared spectroscopy. Although patients without OD showed the typical hemodynamic pattern of increased oxyhemoglobin and reduced deoxyhemoglobin (HHb) concentration, those with OD showed persistent incremental increases of HHb concentration that began at the loading of occlusal strips on their molars before they executed grinding. The intensities of the task‐related HHb activities showed statistically significant differences between OD and control groups, particularly at channel 3, arranged over the left frontal pole cortex. When the discrimination criterion was set using the intensity values of channel 3 from both groups, the overall accuracy of the OD discrimination was 92.9%. Although physiological interpretation has yet to be elucidated, the task‐related response of an increase in HHb may be a useful neuronal signature to characterize dental patients with OD. PMID:29744159

Open disclosure: ethical, professional and legal obligations, and the way forward for regulation.

PubMed

Finlay, Angus J F; Stewart, Cameron L; Parker, Malcolm

2013-05-06

Open disclosure (OD) after adverse health care events is the subject of a national standard that has been implemented in state health policy documents, and is included in the Medical Board of Australia's code of conduct for doctors. Nevertheless, doctors have been slow to embrace the practice of OD. There is a strong ethical case for implementing OD in the primary interests of patients, and additionally from a medicolegal risk management point of view. There are no statutory requirements in relation to OD, but common law judgments have imposed a duty of OD in tort and contract. There are a number of barriers to the better uptake and implementation of OD, including perceptions of legal risk, lack of education and training, reluctance to admit error, uncertainty concerning what and how much to disclose, and the variations in state and territory "apology laws". The implementation of OD could be improved by making apology laws consistent across jurisdictions, including providing "blanket" cover for admissions of fault; by preventing insurers voiding contracts when apologies are made, either through self-regulation or legislation; and by inserting OD obligations into different structures within the health system.

Effects of sonochemical treatment on meteoritic nanodiamonds

NASA Astrophysics Data System (ADS)

Fisenko, Anatolii V.; Verchovsky, Sasha B.; Shiryaev, Andrei A.; Semjonova, Luba F.

2017-01-01

A nanodiamond-rich fraction (NDF) separated from the Orgueil meteorite was subjected to a high-intensity ultrasonic treatment in a weakly acidic aqueous solution. After sedimentation by centrifugation, two fractions of grains (suspension, designated as OD7C and sediment, designated as OD7D) with different properties have been obtained. The following effects of the sonication were revealed from comparison of the contents and isotope compositions of C, N, and Xe released during stepped pyrolysis and combustion of the fractions OD7C and OD7D, the initial NDF and two grain-size fractions (OD10 and OD15) produced without sonication (a) surface layer of the sonicated diamond grains is modified to different extent in comparison with nontreated ones, (b) in some grains concentrations of the bulk N and Xe a reduced significantly, and (c) nondiamond nitrogen containing phases (e.g., Si3N4) have been destroyed. It is suggested that combined effects of the sonication and centrifugation observed for the fractions OD7C and OD7D are due to differences in surface chemistry of the nanodiamond grains, which statistically influences behavior of nanoparticles during the sonication resulting in their preferential modification in the different reaction zones of the cavitating fluid.

Characterization of oxide nanoparticles in Al-free and Al-containing oxide dispersion strengthened ferritic steels.

PubMed

Lee, Jae Hoon; Kim, Jeoung Han

2013-09-01

Oxide nanoparticles in oxide dispersion strengthened (ODS) ferritic steels with and without Al have been characterized by transmission electron microscopy. It is confirmed that most of the complex oxide particles consist of Y2TiO5 for 18Cr-ODS steel and YAlO3 or YAl5O12 for 18Cr5Al-ODS steel, respectivley. The addition of 5% Al in 18Cr-ODS steel leads to the formation of larger oxide particles and the reduction in their number density. For 18Cr-ODS steel, 87% of the oxide particles are coherent. The misfit strain of the coherent particles and a few semi-coherent particles is about 0.034 and 0.056, respectively. For 18Cr5Al-ODS steel, 75% of the oxide particles are semi-coherent, of which the misfit strain is 0.091 and 0.125, respectively. These results suggest that for the Al-containing ODS steel the Al addition accelerates the formation of semi-coherent oxide particles and its larger coherent and semi-coherent particles result in the larger misfit strain between the oxide particle and alloy matrix, indicating that the coherence of oxide nanoparticles in ODS steels is size-dependent.

Transmission electron microscopy study of the heavy-ion-irradiation-induced changes in the nanostructure of oxide dispersion strengthened steels

NASA Astrophysics Data System (ADS)

Rogozhkin, S. V.; Bogachev, A. A.; Orlov, N. N.; Korchuganova, O. A.; Nikitin, A. A.; Zaluzhnyi, A. G.; Kozodaev, M. A.; Kulevoy, T. V.; Kuibeda, R. P.; Fedin, P. A.; Chalykh, B. B.; Lindau, R.; Hoffman, Ya.; Möslang, A.; Vladimirov, P.; Klimenkov, M.

2017-07-01

Transmission electron microscopy was used to study the effect of heavy-ion irradiation on the structure and the phase state of three oxide dispersion strengthened (ODS) steels: ODS Eurofer, ODS 13.5Cr, and ODS 13.5Cr-0.3Ti (wt %). Samples were irradiated with iron and titanium ions to fluences of 1015 and 3 × 1015 cm-2 at 300, 573, and 773 K. The study of the region of maximum radiation damage shows that irradiation increases the number density of oxide particles in all samples. The fraction of fine inclusions increases in the particle size distribution. This effect is most pronounced in the ODS 13.5Cr steel irradiated with titanium ions at 300 K to a fluence of 3 × 1015 cm-2. It is demonstrated that oxide inclusions in ODS 13.5Cr-0.3Ti and ODS 13.5Cr steels are more stable upon irradiation at 573 and 773 K than upon irradiation at 300 K.

Elevated Temperature Compressive Strength Properties of Oxide Dispersion Strengthened NiAl After Cryo-milling and Roasting in Nitrogen

NASA Technical Reports Server (NTRS)

Whittenberger, J. Daniel; Grahle, Peter; Arzt, Eduard; Hebsur, Mohan

1998-01-01

In an effort to superimpose two different elevated temperature strengthening mechanisms in NiAl, several lots of oxide dispersion strengthened (ODS) NiAl powder have been cryo-milled in liquid nitrogen to introduce AlN particles at the grain boundaries. As an alternative to cryo-milling, one lot of ODS NiAl was roasted in nitrogen to produce AlN. Both techniques resulted in hot extruded AlN-strengthened, ODS NiAl alloys which were stronger than the base ODS NiAl between 1200 and 1400 K. However, neither the cryo-milled nor the N2-roasted ODS NiAl alloys were as strong as cryo-milled binary NiAl containing like amounts of AlN. The reason(s) for the relative weakness of cryo-milled ODS NiAl is not certain; however the lack of superior strength in N2-roasted ODS NiAl is probably due to its relatively large AlN particles.

BENCH-SCALE STUDIES ON THE SIMULTANEOUS FORMATION OF PCBS AND PCDDS/FS FROM COMBUSTION SYSTEMS

EPA Science Inventory

The paper reports on a bench-scale experimental study to characterize a newly built reactor system that was built to: produce levels and distributions of polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/F) production similar to those achieved by previous re...

ON-ROAD EMISSION SAMPLING OF A HEAVY DUTY DIESEL VEHICLE FOR POLYCHLORINATED DIBENZO-P-DIOXINS AND POLYCHLORINATED DIBENZOFURANS

EPA Science Inventory

The first known program to characterize mobile heavy diesel vehicle emissions for polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs) during highway and in-city driving routes was successfully conducted. The post-muffler exhaust of a diesel tractor haul...

PAPER FIBERS AS A CARBON SOURCE FOR THE DE NOVO FORMATION OF POLYCHLORINATED DIOXINS AND FURANS

EPA Science Inventory

Formation of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzefurans (PCDDs/Fs) from carbons that were produced from pyrolysis of paper fibers and from a wood charcoal was investigated experimentally. Fibers obtained from a filter paper were pyrolyzed at 300 and 800 d...

Verification Results of Jet Resonance-enhanced Multiphoton Ionization as a Real-time PCDD/F Emission Monitor

EPA Science Inventory

The Jet REMPI (Resonance Enhanced Multiphoton Ionization) monitor was tested on a hazardous waste firing boiler for its ability to determine concentrations of polychlorinated dibenzodioxins and dibenzofurans (PCDDs/Fs). Jet REMPI is a real time instrument capable of highly selec...

PERFORMANCE RESULTS OF JET-REMPI AS A REAL-TIME PCDD/F EMISSION MONITOR

EPA Science Inventory

The Jet REMPI monitor was recently tested on a hazardous-waste firing boiler for its ability to determine real time concentrations of polychlorinated dibenzodioxins and dibenzofurans (PCDDs/Fs). Jet REMPI consists of a laser system coupled with a time of flight mass spectrometer ...

REAL TIME MONITORING OF PCDD/PCDF FOR TRANSIENT CHARACTERIZATION AND PROCESS CONTROL

EPA Science Inventory

Current sampling methods for PCDD/F emission compliance make use of a sample taken during steady state conditions which is assumed to be representative of facility performance. This is often less than satisfactory. The rapid variation of PCDDs, PCDF, and other co-pollutants due ...

EFFECTS OF SENSITIZERS AND INHIBITORS ON PHOTOTRANSFORMATION OF POLYCHLORINATED DIBENZO-P-DIOXINS (PCDDS). (R825549C049)

EPA Science Inventory

The present study was designed to obtain a measure of the change in phototransformation efficiency in the presence of other chemicals. The efficiency of the phototransformation was evaluated by determining quantum yield and photohalf-lives of polychlorinated dibenzo-p-dioxins ...

Prehospital Naloxone Administration as a Public Health Surveillance Tool: A Retrospective Validation Study.

PubMed

Lindstrom, Heather A; Clemency, Brian M; Snyder, Ryan; Consiglio, Joseph D; May, Paul R; Moscati, Ronald M

2015-08-01

Abuse or unintended overdose (OD) of opiates and heroin may result in prehospital and emergency department (ED) care. Prehospital naloxone use has been suggested as a surrogate marker of community opiate ODs. The study objective was to verify externally whether prehospital naloxone use is a surrogate marker of community opiate ODs by comparing Emergency Medical Services (EMS) naloxone administration records to an independent database of ED visits for opiate and heroin ODs in the same community. A retrospective chart review of prehospital and ED data from July 2009 through June 2013 was conducted. Prehospital naloxone administration data obtained from the electronic medical records (EMRs) of a large private EMS provider serving a metropolitan area were considered a surrogate marker for suspected opiate OD. Comparison data were obtained from the regional trauma/psychiatric ED that receives the majority of the OD patients. The ED maintains a de-identified database of narcotic-related visits for surveillance of narcotic use in the metropolitan area. The ED database was queried for ODs associated with opiates or heroin. Cross-correlation analysis was used to test if prehospital naloxone administration was independent of ED visits for opiate/heroin ODs. Naloxone was administered during 1,812 prehospital patient encounters, and 1,294 ED visits for opiate/heroin ODs were identified. The distribution of patients in the prehospital and ED datasets did not differ by gender, but it did differ by race and age. The frequency of naloxone administration by prehospital providers varied directly with the frequency of ED visits for opiate/heroin ODs. A monthly increase of two ED visits for opiate-related ODs was associated with an increase in one prehospital naloxone administration (cross-correlation coefficient [CCF]=0.44; P=.0021). A monthly increase of 100 ED visits for heroin-related ODs was associated with an increase in 94 prehospital naloxone administrations (CCF=0.46; P=.0012). Frequency of naloxone administration by EMS providers in the prehospital setting varied directly with frequency of opiate/heroin OD-related ED visits. The data correlated both for short-term frequency and longer term trends of use. However, there was a marked difference in demographic data suggesting neither data source alone should be relied upon to determine which populations are at risk within the community.

OD in Schools: The State of the Art. Vol. II: Review of Research on OD. Final Report.

ERIC Educational Resources Information Center

Fullan, Michael; And Others

The purpose of this document, the second of a five-volume series, was to analyze the various reviews of organizational development (OD) in general, and case studies of school districts in particular, in order to synthesize information about OD as it applies to schools. The review is organized into four main categories: (1) values, themes, and…

OD in Schools: The State of the Art. Vol. IV: Case Studies. Final Report.

ERIC Educational Resources Information Center

Fullan, Michael; And Others

This volume, the fourth of a five-volume series, contains three onsite case studies of organization development (OD) selected from a sample of 76 school districts. The purpose of the case studies was to analyze in detail different types of OD programs and their use. Each case study represents a different OD focus: case study A involves a survey…

Occupational diseases in the automotive industry in Czechia - Geographic and medical context.

PubMed

Jarolímek, Jan; Urban, Pavel; Pavlínek, Petr; Dzurova, Dagmar

2017-05-08

The automotive industry represents the most important industrial sector in Czechia. The objective of this study has been to analyze the occurrence of occupational diseases (OD) in the automotive industry during the period from 2001 till 2014. Data on OD cases was retrieved from the National Registry of OD. Further, we conducted a survey in automotive companies with focus on occupational health services and positions of the companies in global production networks (GPNs). An analysis of OD distribution in the automotive industry was performed (age, gender, company size and its role in GPNs, regional distribution of studied companies, and regional unemployment rate), and was accompanied by assessment of the quality and range of occupational health services. Employees older than 40 years old have nearly 2.5 times higher probability of OD occurrence as compared with employees younger than 40 years old (odds ratio (OR) = 2.41, 95% confidence interval (CI): 2.05-2.85). Occupational diseases occurrence probability was 3 times higher for women than for men (OR = 3.01, 95% CI: 2.55-3.55). Occupational diseases incidence rates increased with the size of the company (0 OD/10 000 employees in micro enterprises to 57 OD/10 000 employees in large enterprises). A particularly steep rise in OD incidents in the automotive industry was observed in the Plzeň Region between 2001 and 2011. An association between OD incidents and the unemployment rate was not statistically confirmed. A statistically significant increase in OD incidents dependent on company size may be arguably attributed to a higher quality of occupational medical services in bigger companies, which ensures better detection and diagnosis of OD. In the Plzeň Region, the rapid increase in OD incidents was mainly caused by a change in the production process of automobile textiles in one factory due to the introduction of a glue containing isocyanates, which are potent allergising agents. This led to an increase in occupational allergic diseases - bronchial asthma in particular. Int J Occup Med Environ Health 2017;30(3):455-468. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Obtaining optic disc center and pixel region by automatic thresholding methods on morphologically processed fundus images.

PubMed

Marin, Diego; Gegundez-Arias, Manuel E; Suero, Angel; Bravo, Jose M

2015-02-01

Development of automatic retinal disease diagnosis systems based on retinal image computer analysis can provide remarkably quicker screening programs for early detection. Such systems are mainly focused on the detection of the earliest ophthalmic signs of illness and require previous identification of fundal landmark features such as optic disc (OD), fovea or blood vessels. A methodology for accurate center-position location and OD retinal region segmentation on digital fundus images is presented in this paper. The methodology performs a set of iterative opening-closing morphological operations on the original retinography intensity channel to produce a bright region-enhanced image. Taking blood vessel confluence at the OD into account, a 2-step automatic thresholding procedure is then applied to obtain a reduced region of interest, where the center and the OD pixel region are finally obtained by performing the circular Hough transform on a set of OD boundary candidates generated through the application of the Prewitt edge detector. The methodology was evaluated on 1200 and 1748 fundus images from the publicly available MESSIDOR and MESSIDOR-2 databases, acquired from diabetic patients and thus being clinical cases of interest within the framework of automated diagnosis of retinal diseases associated to diabetes mellitus. This methodology proved highly accurate in OD-center location: average Euclidean distance between the methodology-provided and actual OD-center position was 6.08, 9.22 and 9.72 pixels for retinas of 910, 1380 and 1455 pixels in size, respectively. On the other hand, OD segmentation evaluation was performed in terms of Jaccard and Dice coefficients, as well as the mean average distance between estimated and actual OD boundaries. Comparison with the results reported by other reviewed OD segmentation methodologies shows our proposal renders better overall performance. Its effectiveness and robustness make this proposed automated OD location and segmentation method a suitable tool to be integrated into a complete prescreening system for early diagnosis of retinal diseases. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Oncology drugs for orphan indications: how are HTA processes evolving for this specific drug category?

PubMed

Adkins, Elizabeth M; Nicholson, Lindsay; Floyd, David; Ratcliffe, Mark; Chevrou-Severac, Helene

2017-01-01

Orphan drugs (ODs) are intended for the diagnosis, prevention, or treatment of rare diseases. Many cancer subtypes, including all childhood cancers, are defined as rare diseases, and over one-third of ODs are now intended to treat oncology indications. However, market access for oncology ODs is becoming increasingly challenging; ODs are prone to significant uncertainty around their cost-effectiveness, while payers must balance the need for these vital innovations with growing sensitivity to rising costs. The objective of this review was to evaluate different mechanisms that have been introduced to facilitate patient access to oncology ODs in five different countries (Australia, Canada, England, France, and Sweden), using eight oncology ODs and non-orphan oncology drugs as examples of their application. A targeted literature review of health technology assessment (HTA) agency websites was undertaken to identify country-specific guidance and HTA documentation for recently evaluated oncology ODs and non-orphan oncology drugs. None of these countries were found to have explicit HTA criteria for the assessment of ODs, and therefore, oncology ODs are assessed through the usual HTA process. However, distinct and additional processes are adopted to facilitate access to oncology ODs. Review of eight case-study drugs showed that these additional assessment processes were rarely used, and decisions were largely driven by proving cost-effectiveness using standard incremental cost-effectiveness ratio (ICER) thresholds. The predominant implication arising from this study is that application of standard HTA criteria to oncology ODs in many countries fails to take into account any uncertainties around their clinical- and cost-effectiveness, resulting in disparities in HTA reimbursement decisions based on differences in addressing or accepting uncertainty. In order to address this issue, HTA agencies should adopt a more flexible approach to cost-effectiveness, as typified by the Tandvårds-och Läkemedelsförmånsverket in Sweden, which takes into account the small patient numbers involved, limited budget impact, and high unmet medical needs.

Oncology drugs for orphan indications: how are HTA processes evolving for this specific drug category?

PubMed Central

Adkins, Elizabeth M; Nicholson, Lindsay; Floyd, David; Ratcliffe, Mark; Chevrou-Severac, Helene

2017-01-01

Orphan drugs (ODs) are intended for the diagnosis, prevention, or treatment of rare diseases. Many cancer subtypes, including all childhood cancers, are defined as rare diseases, and over one-third of ODs are now intended to treat oncology indications. However, market access for oncology ODs is becoming increasingly challenging; ODs are prone to significant uncertainty around their cost-effectiveness, while payers must balance the need for these vital innovations with growing sensitivity to rising costs. The objective of this review was to evaluate different mechanisms that have been introduced to facilitate patient access to oncology ODs in five different countries (Australia, Canada, England, France, and Sweden), using eight oncology ODs and non-orphan oncology drugs as examples of their application. A targeted literature review of health technology assessment (HTA) agency websites was undertaken to identify country-specific guidance and HTA documentation for recently evaluated oncology ODs and non-orphan oncology drugs. None of these countries were found to have explicit HTA criteria for the assessment of ODs, and therefore, oncology ODs are assessed through the usual HTA process. However, distinct and additional processes are adopted to facilitate access to oncology ODs. Review of eight case-study drugs showed that these additional assessment processes were rarely used, and decisions were largely driven by proving cost-effectiveness using standard incremental cost-effectiveness ratio (ICER) thresholds. The predominant implication arising from this study is that application of standard HTA criteria to oncology ODs in many countries fails to take into account any uncertainties around their clinical- and cost-effectiveness, resulting in disparities in HTA reimbursement decisions based on differences in addressing or accepting uncertainty. In order to address this issue, HTA agencies should adopt a more flexible approach to cost-effectiveness, as typified by the Tandvårds-och Läkemedelsförmånsverket in Sweden, which takes into account the small patient numbers involved, limited budget impact, and high unmet medical needs. PMID:28652787

Occupational syncarcinogenesis in the skin - combined effects of two carcinogens from the German occupational disease list.

PubMed

Dickel, Heinrich; Blome, Otto; Dickel, Beate; Bruckner, Thomas; Stockfleth, Eggert; Soemantri, Silas Paras

2016-12-01

Though scientifically undisputed, cutaneous syncarcinogenesis is not reflected in German occupational disease (OD) regulations, which tend to be guided by the tenet of monocausality. Recognition of nonmelanoma skin cancer (NMSC) and its precursor lesions as OD requires individual assessment as to whether the requirements pursuant to either OD 5103 (occupational exposure to natural UV radiation) or OD 5102 (occupational exposure to polycyclic aromatic hydrocarbons) are fulfilled. Retrospective analysis of 28 patients (median age 72.5 years) with NMSC and respective precursor lesions who had been occupationally exposed to natural UV radiation and polycyclic aromatic hydrocarbons. All cases had undergone expert medical assessment between September 2012 and September 2015. According to our assessments, all 28 cases met the occupational requirements pursuant to OD 5103 and 5102. In 26 cases (93 %), we recommended recognition of skin cancer as occupational disease pursuant to both OD 5103 and OD 5102. The competent occupational insurance association (BG) followed our recommendation in four cases. In eight cases, recognition was solely based on OD 5103; in ten cases, only on OD 5102. Four cases were denied recognition. Following adequate cumulative occupational exposure to natural UV light as well as occupational exposure to polycyclic aromatic hydrocarbons, NMSC or its precursor lesions arising in UV-exposed areas should be reported to the competent occupational insurance association as "OD 5103 and 5102 in terms of syncarcinogenesis". Apart from the fact that the ensuing recognition proceedings will be able to more adequately reflect real-life workplace conditions, filing a report pursuant to both ODs also allows for recognition of basal cell carcinoma as occupational disease. According to current regulations, this would not be possible, if the assessment were solely based on OD 5103. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Preeclampsia in autologous and oocyte donation pregnancy: is there a different pathophysiology?

PubMed

Lashley, Lisa E E L O; Buurma, Aletta; Swings, Godelieve M J S; Eikmans, Michael; Anholts, Jacqueline D H; Bakker, Jaap A; Claas, Frans H J

2015-06-01

Oocyte donation (OD) is a specific method of artificial reproductive technology that is accompanied by a higher risk of preeclampsia during pregnancy. The pathophysiological mechanism underlying preeclampsia in OD pregnancies is thought to differ from preeclampsia in autologous pregnancies. As preeclampsia in autologous pregnancies is suggested to be associated with complement activation, we studied C4d deposition, circulating complement components and placental complement regulatory proteins in preeclamptic OD pregnancies. Women with uncomplicated and preeclamptic pregnancies after OD or spontaneous conception were selected. We stained the placentas for C4d, marker for complement activation, measured complement factors C1q, C3 and C4 in maternal sera and quantified the placental mRNA expression of complement regulatory proteins CD46, CD55 and CD59. A significantly (p < 0.03) higher incidence of C4d deposition was observed in placentas from women with preeclampsia compared with uncomplicated pregnancies, both OD and autologous. The level of complement factors in serum did not differ between the groups. Children born in the autologous preeclampsia group were significantly lower in birth weight (p < 10th percentile) compared with the preeclamptic OD group. In addition, the placental mRNA expression level of complement regulatory proteins was significantly lower in uncomplicated and preeclamptic OD compared with the autologous pregnancies. In line with autologous preeclampsia pregnancies, there is excessive activation of complement in preeclamptic OD pregnancies. However, in contrast to autologous pregnancies this is not associated with counterbalancing upregulation of complement regulatory proteins. Furthermore, C4d deposition in OD pregnancies is not related to the severity of preeclampsia, suggesting another trigger or regulatory mechanism of placental C4d deposition in preeclamptic OD pregnancies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Frontal Metabolite Concentration Deficits in Opiate Dependence Relate to Substance Use, Cognition, and Self-Regulation

PubMed Central

Murray, Donna E; Durazzo, Timothy C; Schmidt, Thomas P; Abé, Christoph; Guydish, Joseph; Meyerhoff, Dieter J

2016-01-01

Objective Proton magnetic resonance spectroscopy (1H MRS) in opiate dependence showed abnormalities in neuronal viability and glutamate concentration in the anterior cingulate cortex (ACC). Metabolite levels in dorsolateral prefrontal cortex (DLPFC) or orbitofrontal cortex (OFC) and their neuropsychological correlates have not been investigated in opiate dependence. Methods Single-volume proton MRS at 4 Tesla and neuropsychological testing were conducted in 21 opiate-dependent individuals (OD) on buprenorphine maintenance therapy. Results were compared to 28 controls (CON) and 35 alcohol-dependent individuals (ALC), commonly investigated treatment-seekers providing context for OD evaluation. Metabolite concentrations were measured from ACC, DLPFC, OFC and parieto-occipital cortical (POC) regions. Results Compared to CON, OD had lower concentrations of N-acetylaspartate (NAA), glutamate (Glu), creatine +phosphocreatine (Cr) and myo-Inositol (mI) in the DLPFC and lower NAA, Cr, and mI in the ACC. OD, ALC, and CON were equivalent on metabolite levels in the POC and γ-aminobutyric acid (GABA) concentration did not differ between groups in any region. In OD, prefrontal metabolite deficits in ACC Glu as well as DLPFC NAA and choline containing metabolites (Cho) correlated with poorer working memory, executive and visuospatial functioning; metabolite deficits in DLPFC Glu and ACC GABA and Cr correlated with substance use measures. In the OFC of OD, Glu and choline-containing metabolites were elevated and lower Cr concentration related to higher nonplanning impulsivity. Compared to 3 week abstinent ALC, OD had significant DLPFC metabolite deficits. Conclusion The anterior frontal metabolite profile of OD differed significantly from that of CON and ALC. The frontal lobe metabolite abnormalities in OD and their neuropsychological correlates may play a role in treatment outcome and could be explored as specific targets for improved OD treatment. PMID:27695638

A review of occupational disease surveillance systems in Modernet countries.

PubMed

Carder, M; Bensefa-Colas, L; Mattioli, S; Noone, P; Stikova, E; Valenty, M; Telle-Lamberton, M

2015-11-01

To improve occupational health public policies and to facilitate coordinated research within the European Union to reduce the incidence of occupational diseases (ODs), it is important to know what OD surveillance systems exist and how they compare. Monitoring trends in occupational diseases and tracing new and emerging risks in a network (Modernet) participants are well placed to provide this information as most either contribute data to and/or are involved in the management of OD systems. To identify and describe OD surveillance systems in Modernet countries with the longer-term objective of identifying a core template to be used on a large scale. A questionnaire sent to Modernet participants, seeking structured information about the OD surveillance system(s) in their country. Overall 14 countries (70%) provided information for 33 OD systems, among them 11 compensation-based (CB) systems. Six countries provided information for non-CB systems reporting for any type of OD. The other systems reported either only ODs from a prescribed list, or specific diagnoses or diagnostic groups, with reports to most schemes being physician-based. Data collected varied but all systems collected diagnosis, age, gender, date reported and occupation (and/or industry) and most collected information on exposure. This review provides information beneficial to both policy makers and researchers by identifying data sources useable to measure OD trends in European countries and opening the way to future work, both on trend comparisons within Europe and on the definition of a core template to extend OD surveillance on a larger scale. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A major locus on mouse chromosome 18 controls XX sex reversal in Odd Sex (Ods) mice.

PubMed

Qin, Yangjun; Poirier, Christophe; Truong, Cavatina; Schumacher, Armin; Agoulnik, Alexander I; Bishop, Colin E

2003-03-01

We have previously reported a dominant mouse mutant, Odd sex (Ods), in which XX Ods/+ mice on the FVB/N background show complete sex reversal, associated with expression of Sox9 in the fetal gonads. Remarkably, when crossed to the A/J strain approximately 95% of the (AXFVB) F(1) XX Ods/+ mice developed as fully fertile, phenotypic females, the remainder developing as males or hermaphrodites. Using a (AXFVB) F(2) population, we conducted a genome-wide linkage scan to identify the number and chromosomal location of potential Ods modifier genes. A single major locus termed Odsm1 was mapped to chromosome 18, tightly linked to D18Mit189 and D18Mit210. Segregation at this locus could account for the presence of sex reversal in 100% of XX Ods/+ mice which develop as males, for the absence of sex reversal in approximately 92% of XX Ods/+ mice which develop as females, and for the mixed sexual phenotype in approximately 72% of XX Ods/+ mice that develop with ambiguous genitalia. We propose that homozygosity for the FVB-derived allele strongly favors Ods sex reversal, whereas homozygosity for the A/J-derived allele inhibits it. In mice heterozygous at Odsm1, the phenotypic outcome, male, female or hermaphrodite, is determined by a complex interaction of several minor modifying loci. The close proximity of Smad2, Smad7 and Smad4 to D18Mit189/210 provides a potential mechanism through which Odsm1 might act.

Oxidation And Hot Corrosion Of ODS Alloy

NASA Technical Reports Server (NTRS)

Lowell, Carl E.; Barrett, Charles A.

1993-01-01

Report reviews oxidation and hot corrosion of oxide-dispersion-strengthened (ODS) alloys, intended for use at high temperatures. Classifies environmental resistances of such alloys by rates of growth of oxides, volatilities of oxides, spalling of oxides, and limitations imposed by hot corrosion. Also discusses environmentally resistant coatings for ODS materials. Concludes ODS NICrAl and FeCrAl alloys highly resistant to oxidation and corrosion and can be used uncoated.

The oxidation and corrosion of ODS alloys

NASA Technical Reports Server (NTRS)

Lowell, Carl E.; Barrett, Charles A.

1990-01-01

The oxidation and hot corrosion of high temperature oxide dispersion strengthened (ODS) alloys are reviewed. The environmental resistance of such alloys are classified by oxide growth rate, oxide volatility, oxide spalling, and hot corrosion limitations. Also discussed are environmentally resistant coatings for ODS materials. It is concluded that ODS NiCrAl and FeCrAl alloys are highly oxidation and corrosion resistant and can probably be used uncoated.

Combustion Engineering, Inc. [LMFBR

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

Not Available

1980-01-01

Four (4) 3 '' O.D. x 0.470'' nominal wall thickness (NWT) hot rotary pierced/roll reduced modified AOD/ESR tube hollows were cold pilger reduced through one pass to 2'' O.D. x 0.250'' NWT tubing. Two (2) additional hollows of same size and process history were cold pilger reduced through one pass to 2 1/8'' O.D. x 0.200'' NWT. Six (6) 3 3/4'' O.D. x 0.600'' NWT hot extruded tube hollows were cold pilger reduced through two passes to 2'' O.D. x 0.250'' NWT tubing. Four of the extrusions represented duplex AOD/ESR melting practice and two extrusions represented AOD melting practice. Twelvemore » (12) pieces of 2 1/8'' O.D. x 0.200'' NWT x approx. 9' long tubing were final heat treated, straightened, and ultrasonically tested. Twelve (12) more pieces of 2 1/8'' O.D. tubing have been solution austenitized (1177/sup 0/C) and are to be reaustenitized (1066/sup 0/C), tempered (760/sup 0/C), straightened, and ultrasonically inspected. All 2'' O.D. x 0.250'' NWT tubing is in the solution austenitized condition. Creep and stress rupture testing has continued on aged material from CarTech heat 91887 and on unaged material from CarTech heat 30182A.« less

Profile differences between overdose and non-overdose suicide attempts in a multi-ethnic Asian society.

PubMed

Ho, Cyrus S H; Ong, Y L; Tan, Gabriel H J; Yeo, S N; Ho, Roger C M

2016-11-08

This study explores differences in characteristics of overdose (OD) and non-overdose (NOD) suicide attempts in Singapore. Four hundred eighty-five medical records of people who attempted suicide were extracted from a local general hospital patient database and classified into OD and NOD groups. Differences in socio-demographic factors, suicide characteristics and hospital admission types between both groups were examined. Indians were more likely than the Chinese and Malays to employ OD method in their attempts. More suicide attempts in the OD group than NOD group were self-reported. The most likely place for suicide attempts for both groups was at home, though more NOD suicide attempts were in public areas as compared to the OD group. Analgesics were the most used substance in the OD group. Those who attempted suicide using OD had a higher number of psychiatric ward admissions than the NOD group. Risk and protective factors varied between both groups. Differences in socio-demographics, suicide characteristics and admission characteristics between OD and NOD groups were observed. Recommendations for suicide prevention in the community are discussed. Further studies on the mediators and moderators of these trends and characteristics of suicide attempts are necessary to ensure maximal efficacy of prevention and management.

Transanal surgery for obstructed defecation syndrome: Literature review and a single-center experience

PubMed Central

Liu, Wei-Cheng; Wan, Song-Lin; Yaseen, SM; Ren, Xiang-Hai; Tian, Cui-Ping; Ding, Zhao; Zheng, Ken-Yan; Wu, Yun-Hua; Jiang, Cong-Qing; Qian, Qun

2016-01-01

Obstructed defecation syndrome (ODS) is a functional disorder commonly encountered by colorectal surgeons and gastroenterologists, and greatly affects the quality of life of patients from both societal and psychological aspects. The underlying anatomical and pathophysiological changes of ODS are complex. However, intra-rectal intussusception and rectocele are frequently found in patients with ODS and both are thought to play an important role in the pathogenesis of ODS. With the development of evaluation methods in anorectal physiology laboratories and radiology studies, a great variety of new operative procedures, especially transanal procedures, have been invented to treat ODS. However, no procedure has been proved to be superior to others at present. Each operation has its own merits and defects. Thus, choosing appropriate transanal surgical procedures for the treatment of ODS remains a challenge for all surgeons. This review provides an introduction of the current problems and options for treatment of ODS and a detailed summary of the essential assessments needed for patient evaluation before carrying out transanal surgery. Besides, an overview of the benefits and problems of current transanal surgical procedures for treatment of ODS is summarized in this review. A report of clinical experience of some transanal surgical techniques used in the authors’ center is also presented. PMID:27672293

Vitamin C deficiency exerts paradoxical cardiovascular effects in osteogenic disorder Shionogi (ODS) rats.

PubMed

Vergely, Catherine; Goirand, Françoise; Ecarnot-Laubriet, Aline; Renard, Céline; Moreau, Daniel; Guilland, Jean-Claude; Dumas, Monique; Rochette, Luc

2004-04-01

Vitamin C is considered to be a very efficient water-soluble antioxidant, for which several new cardiovascular properties were recently described. The aim of this study was to determine in vivo the effects of a severe depletion of vitamin C on cardiac and vascular variables and reperfusion arrhythmias. For this purpose, we used a mutant strain of Wistar rats, osteogenic disorder Shionogi (ODS). After 15 d of consuming a vitamin C-deficient diet, ODS rats had a 90% decrease in plasma and tissue levels of ascorbate compared with ODS vitamin C-supplemented rats and normal Wistar rats. However, plasma antioxidant capacity, proteins, alpha-tocopherol, urate, catecholamines, lipids, and nitrate were not influenced by the vitamin C deficiency in ODS rats. Moreover, there was no difference between ODS vitamin C-deficient and -supplemented rats in heart rate and arterial pressure. After 5 min of an in vivo regional myocardial ischemia, various severe arrhythmias were observed, but their intensities were not modified by vitamin C in vitamin C-deficient ODS rats. The vascular reactivity, measured in vitro on thoracic arteries, was not altered by ascorbate deficiency in ODS rats. These unexpected results suggest that unidentified compensatory mechanisms play a role in maintaining normal cardiac function and vascular reactivity in vitamin C-deficient rats.

Transanal surgery for obstructed defecation syndrome: Literature review and a single-center experience.

PubMed

Liu, Wei-Cheng; Wan, Song-Lin; Yaseen, S M; Ren, Xiang-Hai; Tian, Cui-Ping; Ding, Zhao; Zheng, Ken-Yan; Wu, Yun-Hua; Jiang, Cong-Qing; Qian, Qun

2016-09-21

Obstructed defecation syndrome (ODS) is a functional disorder commonly encountered by colorectal surgeons and gastroenterologists, and greatly affects the quality of life of patients from both societal and psychological aspects. The underlying anatomical and pathophysiological changes of ODS are complex. However, intra-rectal intussusception and rectocele are frequently found in patients with ODS and both are thought to play an important role in the pathogenesis of ODS. With the development of evaluation methods in anorectal physiology laboratories and radiology studies, a great variety of new operative procedures, especially transanal procedures, have been invented to treat ODS. However, no procedure has been proved to be superior to others at present. Each operation has its own merits and defects. Thus, choosing appropriate transanal surgical procedures for the treatment of ODS remains a challenge for all surgeons. This review provides an introduction of the current problems and options for treatment of ODS and a detailed summary of the essential assessments needed for patient evaluation before carrying out transanal surgery. Besides, an overview of the benefits and problems of current transanal surgical procedures for treatment of ODS is summarized in this review. A report of clinical experience of some transanal surgical techniques used in the authors' center is also presented.

The Use of Orientation/Decision/Do/Discuss/Reflect (OD3R) Method to Increase Critical Thinking Skill and Practical Skill in Biochemistry Learning

ERIC Educational Resources Information Center

Anwar, Yunita Arian Sani; Senam, Senam; Laksono, Endang W.

2018-01-01

We have developed an OD3R method that can be applied on Biochemistry learning. This OD3R consists of 5 phases: orientation, decision, do, discuss, and reflect to connect lessons in the class with practice in the laboratory. Implementation of OD3R method was done in 2 universities in Yogyakarta to increase critical thinking skill and practical…

OD in North American Schools: A Scandinavian View, with Comments by Matthew Miles and Michael Fullan. Uppsala Reports on Education, No. 20.

ERIC Educational Resources Information Center

Berg, Gunnar

This report discusses the structural conditions under which organizational development (OD), as employed in the school systems of the United States and Canada, is more or less applicable to schools. The first section (chapters 1-6) reviews papers and books, concerning either OD in general or the ways in which the ideas of OD have been used in the…

Octadecylsilane hybrid silicas prepared by the sol-gel method: morphological and textural aspects.

PubMed

Brambilla, Rodrigo; Pires, Gilvan P; dos Santos, João H Z; Lacerda Miranda, Márcia S

2007-08-15

A series of octadecylsilane-modified silicas was prepared by the sol-gel method through the hydrolysis and cocondensation of tetraethylorthosilicate (TEOS) with octadecyltriethoxysilane (ODS). The ODS:TEOS ratio was varied between 0:100 and 100:0. The resulting carbon content was between 2.5 and 53.4%. In the case of pure ODS, the resulting silica presented 68.6% of C. Hybrid silicas were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, and (29)Si nuclear magnetic resonance spectroscopy. Spheres of ca. 0.5-1.0 microm were obtained in the case of hydrolysis of pure TEOS. The combination of ODS:TEOS ratio yielded systems combining spherical and lamellar patterns zones. Monitoring the particle growth, it seems that spherical particles grow around lamellar zones, these latter concentrating the organosilicon moieties. The degree of cross-linking of ODS moieties was shown to be dependent on the ODS addition time and stirring speed.

Generalizing the transition from amplitude to oscillation death in coupled oscillators.

PubMed

Zou, Wei; Senthilkumar, D V; Koseska, Aneta; Kurths, Jürgen

2013-11-01

Amplitude death (AD) and oscillation death (OD) are two structurally different oscillation quenching types in coupled nonlinear oscillators. The transition from AD to OD has been recently realized due to the interplay between heterogeneity and coupling strength [A. Koseska et al., Phys. Rev. Lett. 111, 024103 (2013)]. We identify here the transition from AD to OD in nonlinear oscillators with couplings of distinct natures. It is demonstrated that the presence of time delay in the coupling cannot induce such a transition in identical oscillators, but it can indeed facilitate its occurrence with a low degree of heterogeneity. Moreover, it is further shown that the AD to OD transition is reliably observed in identical oscillators with dynamic and conjugate couplings. The coexistence of AD and OD and rich stable OD configurations after the transition are revealed, which are of great significance for potential applications in physics, biology, and control studies.

Ultra-high temperature tensile properties of ODS steel claddings under severe accident conditions

NASA Astrophysics Data System (ADS)

Yano, Y.; Tanno, T.; Oka, H.; Ohtsuka, S.; Inoue, T.; Kato, S.; Furukawa, T.; Uwaba, T.; Kaito, T.; Ukai, S.; Oono, N.; Kimura, A.; Hayashi, S.; Torimaru, T.

2017-04-01

Ultra-high temperature ring tensile tests were performed to investigate the tensile behavior of oxide dispersion strengthened (ODS) steel claddings and wrapper materials under severe accident conditions with temperatures ranging from room temperature to 1400 °C which is close to the melting point of core materials. The experimental results showed that the tensile strength of 9Cr-ODS steel claddings was highest in the core materials at ultra-high temperatures of 900-1200 °C, but there was significant degradation in the tensile strength of 9Cr-ODS steel claddings above 1200 °C. This degradation was attributed to grain boundary sliding deformation with γ/δ transformation, which is associated with reduced ductility. By contrast, the tensile strength of recrystallized 12Cr-ODS and FeCrAl-ODS steel claddings retained its high value above 1200 °C, unlike the other tested materials.

Simultaneous macula detection and optic disc boundary segmentation in retinal fundus images

NASA Astrophysics Data System (ADS)

Girard, Fantin; Kavalec, Conrad; Grenier, Sébastien; Ben Tahar, Houssem; Cheriet, Farida

2016-03-01

The optic disc (OD) and the macula are important structures in automatic diagnosis of most retinal diseases inducing vision defects such as glaucoma, diabetic or hypertensive retinopathy and age-related macular degeneration. We propose a new method to detect simultaneously the macula and the OD boundary. First, the color fundus images are processed to compute several maps highlighting the different anatomical structures such as vessels, the macula and the OD. Then, macula candidates and OD candidates are found simultaneously and independently using seed detectors identified on the corresponding maps. After selecting a set of macula/OD pairs, the top candidates are sent to the OD segmentation method. The segmentation method is based on local K-means applied to color coordinates in polar space followed by a polynomial fitting regularization step. Pair scores are updated, resulting in the final best macula/OD pair. The method was evaluated on two public image databases: ONHSD and MESSIDOR. The results show an overlapping area of 0.84 on ONHSD and 0.90 on MESSIDOR, which is better than recent state of the art methods. Our segmentation method is robust to contrast and illumination problems and outputs the exact boundary of the OD, not just a circular or elliptical model. The macula detection has an accuracy of 94%, which again outperforms other macula detection methods. This shows that combining the OD and macula detections improves the overall accuracy. The computation time for the whole process is 6.4 seconds, which is faster than other methods in the literature.

Chemical engineering and structural and pharmacological characterization of the α-scorpion toxin OD1.

PubMed

Durek, Thomas; Vetter, Irina; Wang, Ching-I Anderson; Motin, Leonid; Knapp, Oliver; Adams, David J; Lewis, Richard J; Alewood, Paul F

2013-01-01

Scorpion α-toxins are invaluable pharmacological tools for studying voltage-gated sodium channels, but few structure-function studies have been undertaken due to their challenging synthesis. To address this deficiency, we report a chemical engineering strategy based upon native chemical ligation. The chemical synthesis of α-toxin OD1 was achieved by chemical ligation of three unprotected peptide segments. A high resolution X-ray structure (1.8 Å) of synthetic OD1 showed the typical βαββ α-toxin fold and revealed important conformational differences in the pharmacophore region when compared with other α-toxin structures. Pharmacological analysis of synthetic OD1 revealed potent α-toxin activity (inhibition of fast inactivation) at Nav1.7, as well as Nav1.4 and Nav1.6. In addition, OD1 also produced potent β-toxin activity at Nav1.4 and Nav1.6 (shift of channel activation in the hyperpolarizing direction), indicating that OD1 might interact at more than one site with Nav1.4 and Nav1.6. Investigation of nine OD1 mutants revealed that three residues in the reverse turn contributed significantly to selectivity, with the triple OD1 mutant (D9K, D10P, K11H) being 40-fold more selective for Nav1.7 over Nav1.6, while OD1 K11V was 5-fold more selective for Nav1.6 than Nav1.7. This switch in selectivity highlights the importance of the reverse turn for engineering α-toxins with altered selectivity at Nav subtypes.

Biomechanical and morphological peculiarities of the rectum in patients with obstructed defecation syndrome.

PubMed

Brunenieks, Ints; Pekarska, Katrina; Kasyanov, Vladimir; Groma, Valerija

2017-01-01

The morphological and biomechanical peculiarities of the rectum observed in obstructed defecation syndrome (ODS) are not completely understood. The biomechanical properties and morphological features of the rectum in patients with ODS in correlation with the status of the enteric nervous system (ENS) were evaluated. Uniaxial tensile tests on the rectum samples of patients with ODS and controls were performed; collagenous constituents were assessed by Reticulin and Masson's trichrome stainings; the expressions of α-smooth muscle actin (α-SMA), S100 and CD117 labeling of interstitial cells of Cajal (ICCs) were investigated by immunohistochemistry. In both groups, the ultimate stress in the posterior rectal wall was statistically significantly higher compared to the anterior one. The ultimate strain was higher in ODS compared to controls. The tangential modulus of elasticity was significantly higher in the control group than in the ODS one, both in the anterior and posterior walls. A significantly higher density of collagen demonstrated throughout the wall was evidenced in controls compared to ODS. The mucosal muscular compartment was significantly thicker but more disorganized in the patients group. The enteric S100-positive glial cells were significantly reduced in number in the anterior wall, but elevated in the posterior wall of the rectum in ODS simultaneously demonstrating the higher numbers of ICCs within the entire muscular layer and myenteric. The biomechanical and morphological results show that the rectal wall in patients with ODS is more deformable and less rigid compared to controls. The results of biomechanical properties and morphological changes in the human rectum are essential when choosing the method of ODS treatment.

Same-sample determination of ultratrace levels of polybromodiphenylethers, polybromodibenzo-p-dioxins/furans, and polychlorodibenzo-p-dioxins/furans from combustion flue gas

EPA Science Inventory

The analytical method used for determination of polychlorinated dibenzo-p-dioxins and -furans (PCDDs/Fs) emissions from municipal waste combustors and other stationary sources was modified and validated to enable simultaneous analysis of ultra trace levels of polybrominated diphe...

A PILOT-SCALE STUDY ON THE COMBUSTION OF WASTE ...

EPA Pesticide Factsheets

Symposium Paper Post-consumer carpet is a potential substitute fuel for high temperature thermal processes such as cement kilns and boilers.This paper reports on results examining emissions of PCDDs/Fs from a series of pilot-scale experiments performed on the EPA's rotary kiln incinerator simulator facility in Research triangle Park, NC.

Organization Development

ERIC Educational Resources Information Center

Huse, Edgar F.

1978-01-01

Organization Development (OD) is the application of behavioral-science knowledge to enhance an organization's effectiveness and efficiency. This article discusses the evolution of organization development, the basic components of an OD program, typologies of OD interventions, problems with organization development, and organization development in…

Color deconvolution. Optimizing handling of 3D unitary optical density vectors with polar coordinates.

PubMed

Bigras, Gilbert

2012-06-01

Color deconvolution relies on determination of unitary optical density vectors (OD(3D)) derived from pure constituent stains initially defined as intensity vectors in RGB space. OD(3D) can be defined in polar coordinates (phi, theta, radius); always being equal to one, radius can be ignored. Easier handling of unitary optical density 2D vectors (OD(2D)) is shown. OD(2D) pure stains used in anatomical pathology were assessed as centroid values (phi, theta) with a measure of variance: inertia based on arc lengths between centroid value and sampled points. These variables were plotted on a stereographic projection plane. In order to assess pure stains OD(2D), different methods of sampling RGB pixels were tested and compared: (2) direct sampling of nuclei from preparations using (a) composite H&E and (b) hematoxylin only and (2) for any pure stain RGB image, different associated 8-bit masks (saturation, brightness and RGB average) were used for sampling and compared. Behaviors of phi, theta and inertia were obtained by moving threshold in 8-bit mask histograms. Phi and theta stability were tested against variable light intensity during image acquisition and by using 2 different image acquisition systems. The more saturated RGB pixels are, the more stable phi, theta and inertia values are obtained. Different commercial hematoxylins have distinct OD(2D) characteristics. UltraView DAB stain shows high inertia and is angularly closer to usual counterstains than ultraView Red stain, which also has a lower inertia. Superior accuracy is expected from the latter stain. Phi and theta OD(2D) values are sensitive to light intensity variation, to the used imaging system and to the used objectives. An ImageJ plugin was designed to plot and interactively modify OD(2D) values with instant update of color deconvolution allowing heuristic segmentation. Utilization of polar OD(2D) eases statistical characterization of OD(3D) vectors: conditions of optimal sampling were demonstrated and various factors influencing OD(2D) stability were explored. Stereographic projection plane allows intuitive visualization of OD(3D) vectors as well as heuristic vectorial modification. All findings are not restricted to anatomical pathology but can be applied to bright field microscopy and subtractive color applications in general.

Hindering factors and suggestions related to organ donation decisions: perspective of the Taiwan Ali-Shan Tsou aboriginal tribe.

PubMed

Chen, A N; Chen, K F; Chang, P C; Shih, F Jong; Chen, C R; Shih, F-Jin; Huang, C-Y

2014-05-01

Ali-San Tsou (AST) is one of leading aboriginal tribes in Taiwan with traditional godly beliefs related to life and death. Lacking related knowledge, health professionals (HPs) often failed to help them reach good dying or organ donation (OD). This study aimed to explore hindering factors and suggestions related to OD for good dying from Taiwan AST's own perspective. An explorative qualitative design was employed using a purposive sample of the AST tribes from Taiwan. Data were collected with AST residents by face-to-face interviews and analyzed by content analysis. Thirty AST residents (16 females and 14 males) with ages ranging from 28 to 78 (mean, 54.5) years completed interviews. Of them, 85% reported various diseases. In this study 73% were Catholics and Christians, 17% held traditional godly believes, and 10% had no religious affiliation. Eight hindering factors were reported: (1) limited information about organs and OD; (2) no qualified organs for donation; (3) worry about lack of forgiveness by ancestors; (4) tribe elders who might not accept concept of OD; (5) intact bodies were required at home during spirit-companion rituals; (6) earth burial with intact bodies was preferred; (7) bodies due to accidental and bad death were impermissible for OD; and (8) worry about possession by the donor's spirit. Seven suggestions were also reported for HPs to enhance AST's OD decisions: (1) starting with friendship and a caring relationship; (2) providing spiritual support from reverent religions; (3) stressing good deeds and honoring tribe folks by OD; (4) avoiding accidental/bad death; (5) providing relevant modern medical knowledge of human organs and OD; (6) introducing OD as part of a good-dying care plan; and (7) demonstrating a respectful discussion mindset about OD. Eight hindering factors and 7 types of suggestions for enhancing AST aboriginal people's OD decisions were first explored in this project. In the future, HPs are encouraged to invite AST to share the concepts of OT and try to clarify the related concerns with respect for their cultural contexts. With mutual respect, the efforts of sharing and integrating OD into good-dying care would be more possible. Copyright © 2014 Elsevier Inc. All rights reserved.

Improving accuracy of cell and chromophore concentration measurements using optical density

PubMed Central

2013-01-01

Background UV–vis spectrophotometric optical density (OD) is the most commonly-used technique for estimating chromophore formation and cell concentration in liquid culture. OD wavelength is often chosen with little thought given to its effect on the quality of the measurement. Analysis of the contributions of absorption and scattering to the measured optical density provides a basis for understanding variability among spectrophotometers and enables a quantitative evaluation of the applicability of the Beer-Lambert law. This provides a rational approach for improving the accuracy of OD measurements used as a proxy for direct dry weight (DW), cell count, and pigment levels. Results For pigmented organisms, the choice of OD wavelength presents a tradeoff between the robustness and the sensitivity of the measurement. The OD at a robust wavelength is primarily the result of light scattering and does not vary with culture conditions; whereas, the OD at a sensitive wavelength is additionally dependent on light absorption by the organism’s pigments. Suitably robust and sensitive wavelengths are identified for a wide range of organisms by comparing their spectra to the true absorption spectra of dyes. The relative scattering contribution can be reduced either by measurement at higher OD, or by the addition of bovine serum albumin. Reduction of scattering or correlation with off-peak light attenuation provides for more accurate assessment of chromophore levels within cells. Conversion factors between DW, OD, and colony-forming unit density are tabulated for 17 diverse organisms to illustrate the scope of variability of these correlations. Finally, an inexpensive short pathlength LED-based flow cell is demonstrated for the online monitoring of growth in a bioreactor at culture concentrations greater than 5 grams dry weight per liter which would otherwise require off-line dilutions to obtain non-saturated OD measurements. Conclusions OD is most accurate as a time-saving proxy measurement for biomass concentration when light attenuation is dominated by scattering. However, the applicability of OD-based correlations is highly dependent on the measurement specifications (spectrophotometer model and wavelength) and culture conditions (media type; growth stage; culture stress; cell/colony geometry; presence and concentration of secreted compounds). These variations highlight the importance of treating literature conversion factors as rough approximations as opposed to concrete constants. There is an opportunity to optimize measurements of cell pigment levels by considering scattering and absorption-dependent wavelengths of the OD spectrum. PMID:24499615

In vivo prostacyclin biosynthesis and effects of different aspirin regimens in patients with essential thrombocythaemia.

PubMed

Cavalca, V; Rocca, B; Squellerio, I; Dragani, A; Veglia, F; Pagliaccia, F; Porro, B; Barbieri, S S; Tremoli, E; Patrono, C

2014-07-03

Essential thrombocythaemia (ET) is characterised by enhanced platelet generation and thrombosis. Once daily (od) aspirin incompletely inhibits platelet thromboxane (TX)A2 production in ET. A twice daily (bid) dosing is necessary to fully inhibit TXA2. Whether this dosing regimen affects in vivo prostacyclin (PGI2) biosynthesis is unknown. PGI2 biosynthesis was characterised in 50 ET patients on enteric-coated (EC) aspirin 100 mg od, by measuring its urinary metabolite, 2,3-dinor-6-keto-PGF1α (PGI-M). Moreover, in a crossover study 22 patients poorly responsive to standard aspirin based on serum TXB2 levels (≥4 ng/ml) were randomised to different seven-day aspirin regimens: EC aspirin 100 mg od, 100 mg bid, 200 mg od, or plain aspirin 100 mg od. PGI-M measured 24 hours after the last aspirin intake (EC, 100 mg od) was similar in patients and healthy subjects both on (n=10) and off (n=30) aspirin. PGI-M was unrelated to in vivo TXA2 biosynthesis, and not affected by EC aspirin 100 mg bid or 200 mg od as compared to EC 100 mg od. PGI2 biosynthesis in aspirin-treated ET patients appears unrelated to TXA2 biosynthesis, and not affected by an improved aspirin regimen, demonstrating its vascular safety for future trials.

Occupational diseases in Murmansk Oblast: 1980-2010.

PubMed

Dudarev, Alexey A; Talykova, Liudmila V; Odland, Jon Øyvind

2013-01-01

Official statistics tend to underestimate the incidence of occupational disease (OD) nationally and regionally in Russia. The general aim was to obtain an accurate estimate of ODs in Murmansk Oblast in 1980-2010 and to determine the rate of specific types of ODs among cohorts of workers who had been exposed to the hazardous factors causing the disease. Data were retrieved from the Murmansk Oblast ODs database for the oblast and 2 enterprises--Apatite JSC and Kolskaya MSC--which contributed to more than half of the ODs in the oblast in 1980-2010. The total number of ODs and 5 specific categories (musculoskeletal, respiratory, nervous diseases, hearing loss and vibration disease) were analysed. THE TOTAL RATE OF ODS AMONG WORKERS OF MAIN SHOPS IN BOTH ENTERPRISES WHO WERE ACTUALLY EXPOSED TO HARMFUL FACTORS WERE EXTREMELY HIGH: the rate for Apatite JSC was 25 times higher than in Russia and 15 times higher than in Murmansk Oblast, while the rate for Kolskaya MSC was about 30 and 20 times greater than in Russia and in Murmansk Oblast, respectively; in the 2000s the difference reached 100-150 times. The rise in reported ODs in both enterprises corresponded to the time when intensive medical examinations were conducted by the Kola Research Laboratory for Occupational Health (KRLOH) in Kirovsk. A similar pattern was also observed for the sub-categories of musculoskeletal, respiratory, nervous diseases, hearing loss and vibration disease. It is likely that the true burden of OD is even higher due to misdiagnosis, reluctance of workers concerned about job security to present for care and the lack of reliable information on working conditions needed to establish a causal link between disease and occupational exposure. As with many other regions across Russia, ODs in Murmansk Oblast are grossly underestimated. Serious problems exist in the Russian occupational health care system and the collection of occupational health statistics that require urgent, fundamental reform.

Cwf16p Associating with the Nineteen Complex Ensures Ordered Exon Joining in Constitutive Pre-mRNA Splicing in Fission Yeast

PubMed Central

Sasaki-Haraguchi, Noriko; Ikuyama, Takeshi; Yoshii, Shogo; Takeuchi-Andoh, Tomoko; Frendewey, David; Tani, Tokio

2015-01-01

Exons are ligated in an ordered manner without the skipping of exons in the constitutive splicing of pre-mRNAs with multiple introns. To identify factors ensuring ordered exon joining in constitutive pre-mRNA splicing, we previously screened for exon skipping mutants in Schizosaccharomyces pombe using a reporter plasmid, and characterized three exon skipping mutants named ods1 (ordered splicing 1), ods2, and ods3, the responsible genes of which encode Prp2/U2AF59, U2AF23, and SF1, respectively. They form an SF1-U2AF59-U2AF23 complex involved in recognition of the branch and 3′ splice sites in pre-mRNA. In the present study, we identified a fourth ods mutant, ods4, which was isolated in an exon-skipping screen. The ods4 + gene encodes Cwf16p, which interacts with the NineTeen Complex (NTC), a complex thought to be involved in the first catalytic step of the splicing reaction. We isolated two multi-copy suppressors for the ods4-1 mutation, Srp2p, an SR protein essential for pre-mRNA splicing, and Tif213p, a translation initiation factor, in S. pombe. The overexpression of Srp2p suppressed the exon-skipping phenotype of all ods mutants, whereas Tif213p suppressed only ods4-1, which has a mutation in the translational start codon of the cwf16 gene. We also showed that the decrease in the transcriptional elongation rate induced by drug treatment suppressed exon skipping in ods4-1. We propose that Cwf16p/NTC participates in the early recognition of the branch and 3′ splice sites and cooperates with the SF1-U2AF59-U2AF23 complex to maintain ordered exon joining. PMID:26302002

Impact of Perinatal Dioxin Exposure on Infant Growth: A Cross-Sectional and Longitudinal Studies in Dioxin-Contaminated Areas in Vietnam

PubMed Central

Nishijo, Muneko; Tai, Pham The; Nakagawa, Hideaki; Maruzeni, Shoko; Anh, Nguyen Thi Nguyet; Van Luong, Hoang; Anh, Tran Hai; Honda, Ryumon; Morikawa, Yuko; Kido, Teruhiko; Nishijo, Hisao

2012-01-01

Dioxin exposure levels remain elevated in residents living around former US Air Force bases in Vietnam, indicating potential adverse impacts on infant growth. In this study, 210 mother–infant pairs in dioxin-contaminated areas in Vietnam were recruited at the infants’ birth and followed up for 4 months. Perinatal dioxin exposure levels were estimated by measurement of polychlorinated dibenzo-p-dioxins/furans toxic equivalent (PCDDs/Fs-TEQ) in breast milk. The infants’ size was measured at birth and 1 and 4 months after birth, and neurodevelopment was evaluated using the Bayley Scales III at 4 months of age. Among 4 dioxin groups (<25, 25–50, 50–75, ≥75 percentile of PCDDs/Fs-TEQ), cross-sectional comparisons of body size and neurodevelopment scales and comparisons of longitudinally assessed body size were performed respectively. At birth, head circumference of girls in the ≥75 percentile group was significantly larger than those in the <25 and 50–75 percentile groups. At 4 months of age, the weight and body mass index (BMI) of boys in the ≥75 percentile group were significantly lower than those in the other groups. Increase in weight was significantly lower in the ≥75 percentile group in both sexes from birth to 1 month but only in boys at 1–4 months of age. Estimated marginal mean values in a mixed model of weight and BMI during the first 4 months of life were significantly lower in the ≥75 percentile group in boys. In girls, marginal mean values for head circumference were increased with increase in dioxin levels. Only in boys, cognitive, language, and fine motor scores in the ≥75 percentile group were significantly lower than those in the other groups. These results suggested a considerable impact of perinatal dioxin exposure on infant growth, particularly in boys exposed to dioxins at high level of PCDDs/Fs-TEQ. PMID:22815734

Impact of perinatal dioxin exposure on infant growth: a cross-sectional and longitudinal studies in dioxin-contaminated areas in Vietnam.

PubMed

Nishijo, Muneko; Tai, Pham The; Nakagawa, Hideaki; Maruzeni, Shoko; Anh, Nguyen Thi Nguyet; Luong, Hoang Van; Anh, Tran Hai; Honda, Ryumon; Morikawa, Yuko; Kido, Teruhiko; Nishijo, Hisao

2012-01-01

Dioxin exposure levels remain elevated in residents living around former US Air Force bases in Vietnam, indicating potential adverse impacts on infant growth. In this study, 210 mother-infant pairs in dioxin-contaminated areas in Vietnam were recruited at the infants' birth and followed up for 4 months. Perinatal dioxin exposure levels were estimated by measurement of polychlorinated dibenzo-p-dioxins/furans toxic equivalent (PCDDs/Fs-TEQ) in breast milk. The infants' size was measured at birth and 1 and 4 months after birth, and neurodevelopment was evaluated using the Bayley Scales III at 4 months of age. Among 4 dioxin groups (<25, 25-50, 50-75, ≥75 percentile of PCDDs/Fs-TEQ), cross-sectional comparisons of body size and neurodevelopment scales and comparisons of longitudinally assessed body size were performed respectively. At birth, head circumference of girls in the ≥75 percentile group was significantly larger than those in the <25 and 50-75 percentile groups. At 4 months of age, the weight and body mass index (BMI) of boys in the ≥75 percentile group were significantly lower than those in the other groups. Increase in weight was significantly lower in the ≥75 percentile group in both sexes from birth to 1 month but only in boys at 1-4 months of age. Estimated marginal mean values in a mixed model of weight and BMI during the first 4 months of life were significantly lower in the ≥75 percentile group in boys. In girls, marginal mean values for head circumference were increased with increase in dioxin levels. Only in boys, cognitive, language, and fine motor scores in the ≥75 percentile group were significantly lower than those in the other groups. These results suggested a considerable impact of perinatal dioxin exposure on infant growth, particularly in boys exposed to dioxins at high level of PCDDs/Fs-TEQ.

The level of orally ingested vitamin C affected the expression of vitamin C transporters and vitamin C accumulation in the livers of ODS rats.

PubMed

Sone, Yasuko; Ueta, Etsuko; Kodama, Satoru; Sannoumaru, Yasuko; Miyake, Noriko; Sone, Hirohito; Fujiwara, Yoko; Otsuka, Yuzuru; Kondo, Kazuo; Inagaki, Masahiro; Namba, Eiji; Kurata, Tadao; Suzuki, Emiko

2011-01-01

We investigated the effects of vitamin C administration on vitamin C-specific transporters in ODS/ShiJcl-od/od rat livers. The vitamin C-specific transporter levels increased in the livers of the rats not administered vitamin C and decreased in the livers of those administered vitamin C at 100 mg/d, indicating that these transporter levels can be influenced by the amount of vitamin C administered.

Sensitivity and specificity of the Eating Assessment Tool and the Volume-Viscosity Swallow Test for clinical evaluation of oropharyngeal dysphagia.

PubMed

Rofes, L; Arreola, V; Mukherjee, R; Clavé, P

2014-09-01

Oropharyngeal dysphagia (OD) is an underdiagnosed digestive disorder that causes severe nutritional and respiratory complications. Our aim was to determine the accuracy of the Eating Assessment Tool (EAT-10) and the Volume-Viscosity Swallow Test (V-VST) for clinical evaluation of OD. We studied 120 patients with swallowing difficulties and 14 healthy subjects. OD was evaluated by the 10-item screening questionnaire EAT-10 and the bedside method V-VST, videofluoroscopy (VFS) being the reference standard. The V-VST is an effort test that uses boluses of different volumes and viscosities to identify clinical signs of impaired efficacy (impaired labial seal, piecemeal deglutition, and residue) and impaired safety of swallow (cough, voice changes, and oxygen desaturation ≥3%). Discriminating ability was assessed by the AUC of the ROC curve and sensitivity and specificity values. According to VFS, prevalence of OD was 87%, 75.6% with impaired efficacy and 80.9% with impaired safety of swallow including 17.6% aspirations. The EAT-10 showed a ROC AUC of 0.89 for OD with an optimal cut-off at 2 (0.89 sensitivity and 0.82 specificity). The V-VST showed 0.94 sensitivity and 0.88 specificity for OD, 0.79 sensitivity and 0.75 specificity for impaired efficacy, 0.87 sensitivity and 0.81 specificity for impaired safety, and 0.91 sensitivity and 0.28 specificity for aspirations. Clinical methods for screening (EAT-10) and assessment (V-VST) of OD offer excellent psychometric proprieties that allow adequate management of OD. Their universal application among at-risk populations will improve the identification of patients with OD at risk for malnutrition and aspiration pneumonia. © 2014 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.

RENZI SCORE FOR OBSTRUCTED DEFECATION SYNDROME - VALIDATION OF THE PORTUGUESE VERSION ACCORDING TO THE COSMIN CHECKLIST.

PubMed

Caetano, Ana Celia; Dias, Sara; Santa-Cruz, André; Rolanda, Carla

2018-01-01

Recently, the Obstructed Defecation Syndrome score (ODS score) was developed and validated by Renzi to assess clinical staging and to allow evaluation and comparison of the efficacy of treatment of this disorder. Our goal is to validate the Portuguese version of Renzi ODS score, according to the Consensus based Standards for the selection of the Health Measurement Instruments (COSMIN) checklist. Following guidelines for cross-cultural validity, Renzi ODS score was translated into the Portuguese language. Then, a group of patients and healthy controls were invited to fill in the Renzi ODS score at baseline, after 2 weeks and 3 months, respectively. We assessed internal consistency, reliability and measurement error, content and construct validity, responsiveness and interpretability. A total of 113 individuals (77 patients; 36 healthy controls) completed the questionnaire. Seventy and 30 patients repeated the Renzi ODS score after 2 weeks and 3 months respectively. Factor analysis confirmed the unidimensionality of the scale. Cronbach's α coefficient of 0.77 supported item's homogeneity. Weighted quadratic kappa of 0.89 established test-retest reliability. The smallest detectable change at the individual level was 2.66 and at the group level was 0.30. Renzi ODS score and the total (-0.32) and physical (-0.43) SF-36 scores correlated negatively. Patient and control's groups significantly differed (11 points). The change score of Renzi ODS score between baseline and 3 months correlated negatively with the clinical evolution (-0.86). ROC analysis showed minimal important change of 2.00 with AUC 0.97. Neither floor nor ceiling effects were observed. This work validated the Portuguese version of Renzi ODS score. We can now use this reliable, responsive, and interpretable (at the group level) tool to evaluate Portuguese ODS patients.

Sensitivity and specificity of the Eating Assessment Tool and the Volume-Viscosity Swallow Test for clinical evaluation of oropharyngeal dysphagia

PubMed Central

Rofes, L; Arreola, V; Mukherjee, R; Clavé, P

2014-01-01

Background Oropharyngeal dysphagia (OD) is an underdiagnosed digestive disorder that causes severe nutritional and respiratory complications. Our aim was to determine the accuracy of the Eating Assessment Tool (EAT-10) and the Volume-Viscosity Swallow Test (V-VST) for clinical evaluation of OD. Methods We studied 120 patients with swallowing difficulties and 14 healthy subjects. OD was evaluated by the 10-item screening questionnaire EAT-10 and the bedside method V-VST, videofluoroscopy (VFS) being the reference standard. The V-VST is an effort test that uses boluses of different volumes and viscosities to identify clinical signs of impaired efficacy (impaired labial seal, piecemeal deglutition, and residue) and impaired safety of swallow (cough, voice changes, and oxygen desaturation ≥3%). Discriminating ability was assessed by the AUC of the ROC curve and sensitivity and specificity values. Key Results According to VFS, prevalence of OD was 87%, 75.6% with impaired efficacy and 80.9% with impaired safety of swallow including 17.6% aspirations. The EAT-10 showed a ROC AUC of 0.89 for OD with an optimal cut-off at 2 (0.89 sensitivity and 0.82 specificity). The V-VST showed 0.94 sensitivity and 0.88 specificity for OD, 0.79 sensitivity and 0.75 specificity for impaired efficacy, 0.87 sensitivity and 0.81 specificity for impaired safety, and 0.91 sensitivity and 0.28 specificity for aspirations. Conclusions & Inferences Clinical methods for screening (EAT-10) and assessment (V-VST) of OD offer excellent psychometric proprieties that allow adequate management of OD. Their universal application among at-risk populations will improve the identification of patients with OD at risk for malnutrition and aspiration pneumonia. PMID:24909661

Organization Development in Mental Health Services.

ERIC Educational Resources Information Center

Glaser, Edward M.; Backer, Thomas E.

1979-01-01

The term "organization development" (OD) encompasses techniques developed to facilitate communication and collaborative problem solving in work groups. This discussion focuses on defining OD, describing its current use in mental health and human service organizations, and assessing potential payoffs and disadvantages of implementing OD programs in…

Mean curvature and texture constrained composite weighted random walk algorithm for optic disc segmentation towards glaucoma screening.

PubMed

Panda, Rashmi; Puhan, N B; Panda, Ganapati

2018-02-01

Accurate optic disc (OD) segmentation is an important step in obtaining cup-to-disc ratio-based glaucoma screening using fundus imaging. It is a challenging task because of the subtle OD boundary, blood vessel occlusion and intensity inhomogeneity. In this Letter, the authors propose an improved version of the random walk algorithm for OD segmentation to tackle such challenges. The algorithm incorporates the mean curvature and Gabor texture energy features to define the new composite weight function to compute the edge weights. Unlike the deformable model-based OD segmentation techniques, the proposed algorithm remains unaffected by curve initialisation and local energy minima problem. The effectiveness of the proposed method is verified with DRIVE, DIARETDB1, DRISHTI-GS and MESSIDOR database images using the performance measures such as mean absolute distance, overlapping ratio, dice coefficient, sensitivity, specificity and precision. The obtained OD segmentation results and quantitative performance measures show robustness and superiority of the proposed algorithm in handling the complex challenges in OD segmentation.

Examining subtypes of behavior problems among 3-year-old children, Part I: investigating validity of subtypes and biological risk-factors.

PubMed

Harvey, Elizabeth A; Friedman-Weieneth, Julie L; Goldstein, Lauren H; Sherman, Alison H

2007-02-01

This study examined 3-year-old children who were classified as hyperactive (HYP), oppositional-defiant (OD), hyperactive and oppositional defiant (HYP/OD), and non-problem based on mothers' reports of behavior. Using fathers,' teachers,' and observers' ratings of children's behavior, concurrent validity was excellent for the HYP/OD group, moderate for the HYP group, and poor for the OD group. As predicted, both the HYP/OD and HYP groups reported more prenatal/perinatal birth complications and a greater family history of hyperactivity than did non-problem children. Furthermore, the HYP/OD group showed a greater family history of conduct disorder and oppositional defiant disorder (ODD) symptoms than did non-problem children; however, the HYP group also showed a greater family history of ODD than did non-problem children. Results suggest that as early as age 3, these behavior subtypes appear to be linked to biologically-based risk-factors in ways that are consistent with theories of the development of ADHD.

Energy-filtered TEM imaging and EELS study of ODS particles and argon-filled cavities in ferritic-martensitic steels.

PubMed

Klimiankou, M; Lindau, R; Möslang, A

2005-01-01

Oxide-dispersion-strengthened (ODS) ferritic-martensitic steels with yttrium oxide (Y(2)O(3)) have been produced by mechanical alloying and hot isostatic pressing for use as advanced material in fusion power reactors. Argon gas, usually widely used as inert gas during mechanical alloying, was surprisingly detected in the nanodispersion-strengthened materials. Energy-filtered transmission electron microscopy (EFTEM) and electron energy loss spectroscopy (EELS) led to the following results: (i) chemical composition of ODS particles, (ii) voids with typical diameters of 1-6 nm are formed in the matrix, (iii) these voids are filled with Ar gas, and (iv) the high-density nanosized ODS particles serve as trapping centers for the Ar bubbles. The Ar L(3,2) energy loss edge at 245 eV as well as the absorption features of the ODS particle elements were identified in the EELS spectrum. The energy resolution in the EEL spectrum of about 1.0 eV allows to identify the electronic structure of the ODS particles.

High yttria ferritic ODS steels through powder forging

NASA Astrophysics Data System (ADS)

Kumar, Deepak; Prakash, Ujjwal; Dabhade, Vikram V.; Laha, K.; Sakthivel, T.

2017-05-01

Oxide dispersion strengthened (ODS) steels are being developed for future nuclear reactors. ODS Fe-18%Cr-2%W-0.2%Ti steels with 0, 0.35, 0.5, 1 and 1.5% Y2O3 (all compositions in weight%) dispersion were fabricated by mechanical alloying of elemental powders. The powders were placed in a mild steel can and forged in a stream of hydrogen gas at 1473 K. The steels were forged again to final density. The strength of ODS steel increased with yttria content. Though this was accompanied by a decrease in tensile elongation, all the steels showed significant ductility. The ductility in high yttria alloys may be attributed to improved inter-particle bonding between milled powders due to reduction of surface oxides by hydrogen. This may permit development of ODS steels with yttria contents higher than the conventional limit of 0.5%. It is suggested that powder forging is a promising route to fabricate ODS steels with high yttria contents and improved ductility.

Effectiveness and Safety of Sofosbuvir/Ledipasvir and Paritaprevir/ritonavir/Ombitasvir + Dasabuvir in Patients with Chronic Kidney Diseases: Results from ERCHIVES

PubMed Central

Butt, Adeel; Ren, Yanjie; Puenpatom, Amy; Arduino, Jean Marie; Kumar, Ritesh; Abou-Samra, Abdul-Badi

2017-01-01

Abstract Background Chronic kidney disease (CKD) was a relative contraindication to HCV treatment in the interferon/ribavirin era due to poor tolerability and lower efficacy. Our aim was to determine the effectiveness treatment completion, and safety of sofosbuvir/ledipasvir (SOF/LDV) and paritaprevir/ritonavir/ombitasvir/dasabuvir (PrOD) regimens in persons with CKD. Methods We identified all persons started on a SOF/LDV or PrOD regimen in ERCHIVES before 30 April 2016. We excluded those with missing HCV genotype, or eGFR values. We determined treatment completion, sustained virologic response (SVR) rates and proportion of persons with worseningrenal function or developing grade 3/4 anemia. Results We identified 9,837 persons on SOF/LDV, 3,826 on SOF/LDV+RBV, 1,017 on PrOD and 2,944 on PrOD+RBV. Genotype 1a was the predominant genotype for SOF/LDV+RBV (77.3% no RBV; 70.0% with RBV) and PrOD+RBV (79.5%) groups, while only 4.3% of PrOD with no RBV group were genotype 1a. Among treated patients, the prevalence of patients with stage 4–5 CKD was 0.8% (SOF/LDV + RBV), 1.1% (SOF/LDVno RBV), 2.2% (PrOD +RBV) and 5.4% (PrOD no RBV). Among 13,663 total persons on SOF/LDV, 67.8% completed treatment while the treatment completion rate of those on PrOD was 74.0% (N = 2,932/3,961) (Table 1). The overall SVR rates of persons on SOF/LDV or PrOD regimens were 96.3%. A drop in treatment completion rates was seen in CKD stage 4–5 and those on PrOD+RBV, but the impact of RBV on SVR was unclear. While about one-third of the persons with a CKD stage 1–2 experienced a >10 mL/minute/1,73m2, about 15% decline among those with CKD stage 3. The incidence of grade3/4 anemia by CKD stages increased significantly across the treatment groups. Grade 3/4 anemia ranged from 9.7% (SOF/LDV) to 21.8% (PrOD) among patients with CKD stage 4–5 (Table 2). Conclusion SVR rates among persons treated with SOF/LDV or PrOD were high in the CKD population despite 22% not completing the treatment regimen. Incidence of grade3/4 anemia increased significantly in CKD stage 4–5 across the treatment groups. Disclosures A. Butt, Merck: Investigator, Grant recipient.A. Puenpatom, Merck: Employee, Salary. J. M. Arduino, Merck: Employee, Salary. R. Kumar, Merck: Employee, Salary

Oxymetazoline plus dexpanthenol in nasal congestion.

PubMed

Jagade, Mohan V; Langade, Deepak G; Pophale, Rupesh R; Prabhu, Arun

2008-12-01

To compare the efficacy and tolerability of Oxymetazoline 0.05 % plus Dexpanthanol 5% versus Xylometazoline 0.1 % nasal drops in patients with nasal congestion due to allergic rhinitis and following nasal surgery. An investigator-blind, randomized, controlled, phase IV clinical trial conducted in 100 patients with acute allergic rhinitis or patients post-nasal surgery. Patients received either Oxymetazoline 0.05% with Dexpanthanol 5% (OD) or Xylometazoline 0.1% (XO) nasal drops. Relief from nasal congestion was significantly better in the OD group then in the XO group (mean nasal scores 1.24 vs 1.86). Significantly more improvement in sneezing and decrease in nasal discharge was seen in the OD group than the XO group. Nasal irritation in the OD group was significantly less as compared to XO group (0.38 v/s 1.12 on second day and 0.10 vs 0.36 on the fourth day). The recovery time for OD group was 1.08 hours, which was significantly (46 min) lesser than that of the XO group. Rebound congestion was significantly less in OD as compared to XO group (6.25% vs 82.98%). 93.75% of the physicians in the OD group and 51.28% in XO group reported response to therapy as good to excellent. 95.83% patients in the OD group and only 52.91% patients in the XO group rated tolerability to therapy as good to excellent. Oxymetazoline and dexpanthenol combination has a better efficacy, shorter recovery time, causes lesser rebound congestion and has better tolerability than xylometazoline.

Drugs Related to Oropharyngeal Dysphagia in Older People.

PubMed

Miarons, Marta; Campins, Lluís; Palomera, Elisabet; Serra-Prat, Mateu; Cabré, Mateu; Rofes, Laia

2016-10-01

Scientific evidence on the impact of medication on the physiology of swallowing is scarce and mainly based on clinical case reports. To evaluate the association between oropharyngeal dysphagia (OD) and chronic exposure to medication in older patients admitted to the acute geriatric unit (AGU) of a secondary hospital, we performed a retrospective cross-sectional study of 966 patients admitted to an AGU from 2008 to 2011. We reviewed (a) diagnosis of OD (assessed with the volume-viscosity swallow test, V- VST); (b) chronic patient medication classified by anatomical, therapeutic, chemical codes; and (c) demographic and clinical data. A univariate analysis was performed to determine which medications were associated with OD. A multivariate analysis adjusting for confounding clinical factors was performed to identify which of those medications were independently associated with OD. The age of patients included was 85.3 ± 6.37 years and 59.4 % were women. A total of 41.9 % presented OD. We found a possible protective effect of beta blocking agents on OD after the multivariate analysis (OR 0.54, 95 % CI 0.35-0.85). None of the categories of drugs was associated with an altered swallowing function after adjusting for confounding variables. The present study is the first one to widely investigate the association between drugs and OD, increasing understanding of their association. The role of beta blockers in OD needs to be further studied as their potentially beneficial effects on the swallowing function in older patients could help to prevent complications.

[Expression of collagen and elastin fibers in the rectum of patients with obstructed defecation syndrome and its significance].

PubMed

Li, Juan; Lin, Hongcheng; Ren, Donglin

2015-12-01

To detect the expression of collagen and elastin fibers in the rectum of patients with obstructive defecation syndrome (ODS), and to explore the possible role of these fibers in the pathogenesis of ODS. The rectum specimens of 20 patients with ODS were collected. These patients had undergone stapled transanal rectal resection (STARR) surgery in our hospital since 2012. Full-thickness rectal specimens were stained with Masson and EVG staining to show collagen and elastin fibers. As the control, rectum specimens of 20 patients with severe prolapsed hemorrhoids also undergoing STARR surgery in our hospital during the same period were collected. Masson staining showed that the structure of collagen fibers in submucosa was slender, area decreased [(13.88±7.02)% vs. (30.98±3.46)%, P<0.01], and the expression level was significantly lower in ODS group compared with control group. EVG staining also showed that collagen fiber area of ODS patients was reduced compared with control group [(17.18±7.24)% vs. (27.04±9.65)%, P<0.01]. Meanwhile EVG staining revealed that elastic fibers were fragmented in ODS group and the expression level was lower compared with control group [(1.20±1.39)% vs. (1.47±1.06)%], whereas the difference was not statistically significant(P>0.05). The expression level of collagen fibers in patients with ODS is significantly reduced, which may play an important role in the pathogenesis of ODS.

Modulation of Cyclodextrin Particle Amphiphilic Properties to Stabilize Pickering Emulsion.

PubMed

Xi, Yongkang; Luo, Zhigang; Lu, Xuanxuan; Peng, Xichun

2018-01-10

Cyclodextrins have been proven to form complexes with linear oil molecules and stabilize emulsions. Amphiphilic properties of cyclodextrin particles were modulated through esterification reaction between β-cyclodextrin (β-CD) and octadecenyl succinic anhydride (ODSA) under alkaline conditions. ODS-β-CD particles with degree of substitution (DS) of 0.003, 0.011, and 0.019 were obtained. The introduced hydrophobic long chain that was linked within β-CD cavity led to the change of ODS-β-CD in terms of morphological structure, surface charge density, size, and contact angle, upon which the properties and stability of the emulsions stabilized by ODS-β-CD were highly dependent. The average diameter of ODS-β-CD particles ranged from 449 to 1484 nm. With the DS increased from 0.003 to 0.019, the contact angle and absolute zeta potential value of these ODS-β-CD particles improved from 25.7° to 47.3° and 48.1 to 62.8 mV, respectively. The cage structure of β-CD crystals was transformed to channel structure, then further to amorphous structure after introduction of the octadecenyl succinylation chain. ODS-β-CD particles exhibited higher emulsifying ability compared to β-CD. The resulting Pickering emulsions formed by ODS-β-CD particles were more stable during storage. This study investigates the ability of these ODS-β-CD particles to stabilize oil-in-water emulsions with respect to their amphiphilic character and structural properties.

Effect of deuteration on hydrogen bonding: A comparative concentration dependent Raman and DFT study of pyridine in CH3OH and CD3OD and pyrimidine in H2O and D2O

NASA Astrophysics Data System (ADS)

Singh, Anurag; Gangopadhyay, Debraj; Popp, Jürgen; Singh, Ranjan K.

2012-12-01

The relative effect of hydrogen bonding of pyrimidine (Pyr) in H2O/D2O and pyridine (Py) in CH3OH/CD3OD has been analyzed using Raman Difference Spectroscopic (RDS) technique and DFT calculations. This study is focused on analyzing the concentration dependent variation of linewidth, peak position and intensity of ring breathing mode of Py and Pyr. The ring breathing mode of Pyr in H2O and D2O has three components; due to free Pyr, lighter complexes of mPyr + nH2O/D2O and heavier complexes of mPyr + nH2O/D2O. The pyridine molecules, however, show only two components in CH3OH and CD3OD. Of these two components, one corresponds to free Py and the other inhomogeneously broadened profile corresponds to all mPy + nCH3OH/CD3OD complexes. The variation of peak position and linewidth establishes the role of dipole moment of complexes and the diffusion in the mixture. In case of CD3OD solution splitting was observed in ˜1030 cm-1 band of Py, where an additional band at ˜1034 cm-1 appears at x(Py) ⩽ 0.4. However, this band remains single at all concentrations in case of CH3OH solvent.

Ginger Orally Disintegrating Tablets to Improve Swallowing in Older People.

PubMed

Hirata, Ayumu; Funato, Hiroki; Nakai, Megumi; Iizuka, Michiro; Abe, Noriaki; Yagi, Yusuke; Shiraishi, Hisashi; Jobu, Kohei; Yokota, Junko; Hirose, Kahori; Hyodo, Masamitsu; Miyamura, Mitsuhiko

2016-01-01

We previously prepared and pharmaceutically evaluated ginger orally disintegrating (OD) tablets, optimized the base formulation, and carried out a clinical trial in healthy adults in their 20 s and 50s to measure their effect on salivary substance P (SP) level and improved swallowing function. In this study, we conducted clinical trials using the ginger OD tablets in older people to clinically evaluate the improvements in swallowing function resulting from the functional components of the tablet. The ginger OD tablets were prepared by mixing the excipients with the same amount of mannitol and sucrose to a concentration of 1% ginger. Eighteen healthy older adult volunteers aged 63 to 90 were included in the swallowing function test. Saliva was collected before and 15 min after administration of the placebo and ginger OD tablets. Swallowing endoscopy was performed by an otolaryngologist before administration and 15 min after administration of the ginger OD tablets. A scoring method was used to evaluate the endoscopic swallowing. Fifteen minutes after taking the ginger OD tablets, the salivary SP amount was significantly higher than prior to ingestion or after taking the placebo (p<0.05). Among 10 subjects, one scored 1-3 using the four evaluation criteria. Overall, no aspiration occurred and a significant improvement in the swallowing function score was observed (p<0.05) after taking the ginger OD tablets. Our findings showed that the ginger OD tablets increased the salivary SP amount and improved swallowing function in older people with appreciably reduced swallowing function.

Use of computational fluid dynamics to simulate the effects of design and operating parameters on the overall performance

NASA Astrophysics Data System (ADS)

Nasserzadeh, V.; Swithenbank, J.

1995-10-01

With around 10 tonnes of waste being generated for every man, woman and child each year across the globe, safe disposal of it all has become an urgent environmental problem. In 1993, Western Europe, the United States, Canada, Japan, Australia and New Zealand produced a total of 480 million tonnes of industrial waste and 8 billion tonnes from activities such as energy production, agriculture, mining and sewage disposal. The emission to the atmosphere of both heavy metals and acid gases and perhaps more important in the longer term, the Dioxins/Furans (PCDDs/PCDFs), promises to be one of the key issues facing not only the industry but the society as a whole over the next decade and more. Although it is increasingly likely that measures to control toxic emissions will have to be directed at a wider target than just the waste incinerators, it is equally certain that both public opinion and legislation will, at least in the first instance, see the incinerators as one of the most obvious candidates for tighter regulation. These days, virtually all the new research and development techniques in combustion technology involve the application of computational fluid dynamics (CFD) to combustor design. This seems to be the best approach to solving design problems. Mathematical modelling thus is seen as an inherent part of practically all combustion research programmes. The new discipline of computational fluid dynamics can also be used to help minimise flame generated pollutants released to the atmosphere. These pollutants include; CO2, CO, SO2, NOx, HCl, Hydrocarbons, soot, particulates, heavy metals and dioxins/furans. CFD studies of their release to the atmosphere must include not only their source in the flame, but also their removal from the flue gases by scrubbing and other techniques. The governing differential equations for the process being studied must be defined and solved simultaneously if the parameters in the equations are interacting. At present, this procedure can give valuable insight into the effect of design parameters on the flow field and concentrations of major species. In the case of many pollutants, the equations governing their production does not affect the flow field or concentrations of major species. Thus the equations are effectively decoupled and the pollutant formation, convection and diffusion can be calculated in a post-processor. This paper presents and discusses the results of our CFD modelling work at two large municipal and a newly commissioned 5 MW clinical incinerator plants in UK.

An integrative risk assessment approach for persistent chemicals: a case study on dioxins, furans and dioxin-like PCBs in France.

PubMed

Béchaux, Camille; Zeilmaker, Marco; Merlo, Mathilde; Bokkers, Bas; Crépet, Amélie

2014-10-01

For persistent chemicals slowly eliminated from the body, the accumulated concentration (body burden), rather than the daily exposure, is considered the proper starting point for the risk assessment. This work introduces an integrative approach for persistent chemical risk assessment by means of a dynamic body burden approach. To reach this goal a Kinetic Dietary Exposure Model (KDEM) was extended with the long term time trend in the exposure (historic exposure) and the comparison of bioaccumulation with body burden references for toxicity. The usefulness of the model was illustrated on the dietary exposure to PolyChlorinatedDibenzo-p-Dioxins (PCDDs), PolyChlorinatedDibenzoFurans (PCDFs) and PolyChlorinated Biphenyls (PCBs) in France. Firstly the dietary exposure to these compounds was determined in 2009 and combined with its long term time trend. In order to take differences between the kinetics of PCDD/F and dl-PCBs into account, three groups of congeners were considered i.e. PCDD/Fs, PCB 126 and remaining dl-PCBs. The body burden was compared with reference body burdens corresponding to reproductive, hepatic and thyroid toxicity. In the case of thyroid toxicity this comparison indicated that in 2009 the probability of the body burden to exceed its reference ranged from 2.8% (95% CI: 1.5-4.9%) up to 3.9% (95% CI: 2.7-7.1%) (18-29 vs. 60-79year olds). Notwithstanding the decreasing long-term time trend of the dietary dioxin exposure in France, this probability still is expected to be 1.5% (95% CI: 0.3-2.5%) in 2030 in 60-79 olds. In the case of reproductive toxicity the probability of the 2009 body burden to exceed its reference ranged from 3.1% (95% CI: 1.4-5.0%) (18-29year olds) to 3.5% (95% CI: 2.2-5.2%) (30-44year olds). In 2030 this probability is negligible in 18-29year olds, however small though significant in 30-44year olds (0.7%, 95% CI: 0-1.6%). In the case of hepatic toxicity the probability in 2009 even in 60-79year olds already was negligible. In conclusion this approach indicates that in France dioxin levels in food form a declining, though still present, future health risk with respect to thyroid and reproductive toxicity. Copyright © 2014 Elsevier Inc. All rights reserved.

PCDD/Fs and DL-PCBs in feeding fats obtained as co-products or by-products derived from the food chain.

PubMed

Abalos, M; Parera, J; Abad, E; Rivera, J

2008-04-01

Among the tasks included in the "Quality and safety of feeding fats obtained from co-products or by-products of the food chain" Project, supported by the European Union and included in the 6th Framework Program, a number of fats and oils collected as co- or by-products from the food chain were selected for the determination of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and 'dioxin-like' polychlorinated biphenyls (DL-PCBs). In the majority of the cases these samples are currently employed as feed ingredients. Nevertheless, additional fats, which are forbidden for feedstuff purposes were also considered in this study. In general terms, fats and oils were classified taking into account their nature and the processes applied to obtain these co- or by-products. PCDD/F and DL-PCB levels were evaluated in a first group of samples composed of fish oils, animal fats and lecithins. As expected, fats and oils with an animal origin presented higher concentrations, expressed in pg WHO-TEQ/g, compared to the levels found in vegetable samples like lecithins. The category of fish oils had the highest values for both PCDD/Fs and the sum of PCDD/Fs and DL-PCBs, with some samples showing levels above the maximum established at the present legislation related to the presence of PCDD/Fs and DL-PCBs in animal feed [Commission Directive 2006/13/EC of 3 February 2006 amending Annexes I and II to Directive 2002/32/EC of the European Parliament and of the Council on undesirable substances in animal feed as regards dioxins and dioxin-like PCBs. Official Journal of the European Communities L32, 44-53]. In a second group, fats and oils with a more complex composition obtained from different transformation processes or even mixtures of fats were considered; thus, acid oils from chemical refining, acid oils from physical refining, recycled cooking oils, oils extracted from exhausted bleaching earths, hydrogenated by-products, fatty acids calcium soaps and miscellaneous fats were analyzed. The data revealed a significant variability in PCDD/F and DL-PCB levels, expressed in pg WHO-TEQ/g, in these products. It has to be pointed out that the analyses of fats and oils belonging to these categories of products were sometimes difficult due to the complexity of the samples. In terms of legislation most of these samples cannot be easily included into one of the specific categories of substances intended for feedstuff purposes that are regulated in Commission Directive 2006/13/EC.

Variational Bayes method for estimating transit route OD flows using APC data.

DOT National Transportation Integrated Search

2017-01-31

The focus of this study is on the use of large quantities of APC data to estimate OD flows : for transit bus routes. Since most OD flow estimation methodologies based on boarding and : alighting counts were developed before the prevalence of APC tech...

Forms and prevalence of intersexuality and effects of environmental contaminants on sexuality in cricket frogs (Acris crepitans).

PubMed Central

Reeder, A L; Foley, G L; Nichols, D K; Hansen, L G; Wikoff, B; Faeh, S; Eisold, J; Wheeler, M B; Warner, R; Murphy, J E; Beasley, V R

1998-01-01

Cricket frogs (Acris crepitans) from several different sites in Illinois were collected to assess the effects of environmental contamination on the prevalence of intersex gonads. Of 341 frogs collected in 1993, 1994, and 1995, 2.7% were intersex individuals. There was no statistically significant relationship between the chemical compounds detected and cricket frog intersexuality. However, there was an association approaching significance (p = 0.07) between the detection of atrazine and intersex individuals. A comparison of reference sites with sites that had point polychlorinated biphenyl (PCB) and polychlorinated dibenzofuran (PCDF) contamination revealed a significant relationship between sex-ratio reversal and contamination with PCBs and PCDFs. The sex ratio of juvenile frogs studied from three sites with PCB and PCDF point contamination favored males over females, which was the opposite of the sex ratio in control ponds (p = 0.0007). The statistically significant correlation between organochlorine contamination and sex-ratio reversal suggests PCBs and PCDFs can influence cricket frog sexual differentiation. The current study suggests that in cricket frogs, sex ratios and the prevalence of intersex gonads are altered by environmental contamination. Images Figure 1 Figure 2 PMID:9647894

46 CFR 252.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-differential subsidy (ODS) means, except as the operator and the United States government should agree upon a... contracts with the United States government under Title VI of the Act to receive ODS. (m) Reduced crew... for determining the amount of ODS that is to be paid for an item of subsidizable expense. (q...

46 CFR 381.8 - Subsidized vessel participation.

Code of Federal Regulations, 2010 CFR

2010-10-01

... from MARAD an amount for the operating-differential subsidy (ODS) likely to be paid for the carriage of... subsidized bidders; (2) Deriving “augmented bids” for the subsidized operators by adding the ODS amount to... on MARAD's calculation of anticipated costs (less ODS in the case of a subsidized vessel) for the...

Essentials for Successful Organization Development Efforts.

ERIC Educational Resources Information Center

Boss, R. Wayne

1979-01-01

The purpose of organization development (OD) is to improve an organization's effectiveness in making decisions and changes and to reach the full potential of its personnel. Objectives of OD and essentials for successful programs are listed. Definitions of essentials and how they add to the effectiveness of OD are presented. (Author/BEF)

Progress in Organization Development Research.

ERIC Educational Resources Information Center

Roberts, Nancy C.; Porras, Jerry I.

1982-01-01

Describes major areas of progress in organization development (OD): progress in operationalizing the concept of change; progress in improving measurement; and progress in designing statistical procedures used to analyze OD intervention data. Suggests recent research developments point to a more solid base on which to build OD practice and theory.…

46 CFR 280.8 - Certain ODS agreement provisions not affected.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 8 2010-10-01 2010-10-01 false Certain ODS agreement provisions not affected. 280.8 Section 280.8 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION REGULATIONS AFFECTING... LINER OPERATORS § 280.8 Certain ODS agreement provisions not affected. The provisions of this part are...

Towards Healthy Organizations: The Use of Organization Development in Academic Libraries

ERIC Educational Resources Information Center

Parsch, Janet H.; Baughman, M. Sue

2010-01-01

Two surveys assess use of organization development (OD) in Association of Research Libraries. Analysis presents organizational, deans', and staff professionals' perspectives on OD use. The study is the first broad analysis of academic library OD use and supports the concept of the "healthy organization." (Contains 12 tables.)

Emergence of amplitude and oscillation death in identical coupled oscillators.

PubMed

Zou, Wei; Senthilkumar, D V; Duan, Jinqiao; Kurths, Jürgen

2014-09-01

We deduce rigorous conditions for the onset of amplitude death (AD) and oscillation death (OD) in a system of identical coupled paradigmatic Stuart-Landau oscillators. A nonscalar coupling and high frequency are beneficial for the onset of AD. In strong contrast, scalar diffusive coupling and low intrinsic frequency are in favor of the emergence of OD. Our finding contributes to clearly distinguish intrinsic geneses for AD and OD, and further substantially corroborates that AD and OD are indeed two dynamically distinct oscillation quenching phenomena due to distinctly different mechanisms.

The effect of endodontic materials on the optical density of dyes used in marginal leakage studies.

PubMed

Kubo, Claudio Hideki; Valera, Marcia Carneiro; Gomes, Ana Paula Martins; Mancini, Maria Nadir Gasparoto; Camargo, Carlos Henrique Ribeiro

2008-01-01

The aim of this study was to determine the effect of the exposure of different endodontic materials to different dye solutions by evaluating the optical density of the dye solutions. Seventy-five plastic tubes were filled with one of the following materials: AH Plus, Sealapex, Portland cement, MTA (Angelus and Pro Root) and fifteen control plastic tubes were not. Each specimen of material and control was immersed in a container with 1 ml of each dye solution. A 0.1 ml-dye solution aliquote was removed before immersion and after 12, 24, 48 and 72 hours of each specimen immersion to record its optical density (OD) in a spectrophotometer. Statistical analysis was performed with ANOVA and Tukey tests (5%). No significant difference was found among any of the solution OD values for AH Plus cement. Portland cement promoted different OD values after 12 hours of immersion. MTA-Angelus cement presented different OD values only for 2% rhodamine B and the MTA-Pro Root cement presented different OD values in all 2% rhodamine B samples. Sealapex cement promoted a reduction in the India Ink OD values. Dye evaluation through OD seems to be an interesting method to select the best dye solution to use in a given marginal leakage study.

Prevention of the Osmotic Demyelination Syndrome After Liver Transplantation: A Multidisciplinary Perspective.

PubMed

Crismale, J F; Meliambro, K A; DeMaria, S; Bronster, D B; Florman, S; Schiano, T D

2017-10-01

The osmotic demyelination syndrome (ODS) is a serious neurologic condition that occurs in the setting of rapid correction of hyponatremia. It presents with protean manifestations, from encephalopathy to the "locked-in" syndrome. ODS can complicate liver transplantation (LT), and its incidence may increase with the inclusion of serum sodium as a factor in the Mayo End-Stage Liver Disease score. A comprehensive understanding of risk factors for the development of ODS in the setting of LT, along with recommendations to mitigate the risk of ODS, are necessary. The literature to date on ODS in the setting of LT was reviewed. Major risk factors for the development of ODS include severe pretransplant hyponatremia (serum sodium [SNa] < 125 mEq/L), the magnitude of change in SNa pre- versus posttransplant, higher positive intraoperative fluid balance, and the presence of postoperative hemorrhagic complications. Strategies to reduce the risk of ODS include correcting hyponatremia pretransplant via fluid restriction and/or ensuring an appropriate rate of increase from the preoperative SNa via close attention to fluid and electrolyte management both during and after surgery. Multidisciplinary management involving transplant hepatology, nephrology, neurology, surgery, and anesthesiology/critical care is key to performing LT safely in patients with hyponatremia. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

Development of Oxide Dispersion Strengthened (ODS) Ferritic Steel Through Powder Forging

NASA Astrophysics Data System (ADS)

Kumar, Deepak; Prakash, Ujjwal; Dabhade, Vikram V.; Laha, K.; Sakthivel, T.

2017-04-01

Oxide dispersion strengthened (ODS) ferritic steels are candidates for cladding tubes in fast breeder nuclear reactors. In this study, an 18%Cr ODS ferritic steel was prepared through powder forging route. Elemental powders with a nominal composition of Fe-18Cr-2 W-0.2Ti (composition in wt.%) with 0 and 0.35% yttria were prepared by mechanical alloying in a Simoloyer attritor under argon atmosphere. The alloyed powders were heated in a mild steel can to 1473 K under flowing hydrogen atmosphere. The can was then hot forged. Steps of sealing, degassing and evacuation are eliminated by using powder forging. Heating ODS powder in hydrogen atmosphere ensures good bonding between alloy powders. A dense ODS alloy with an attractive combination of strength and ductility was obtained after re-forging. On testing at 973 K, a loss in ductility was observed in yttria-containing alloy. The strength and ductility increased with increase in strain rate at 973 K. Reasons for this are discussed. The ODS alloy exhibited a recrystallized microstructure which is difficult to achieve by extrusion. No prior particle boundaries were observed after forging. The forged compacts exhibited isotropic mechanical properties. It is suggested that powder forging may offer several advantages over the traditional extrusion/HIP routes for fabrication of ODS alloys.

Home-based exercise for elderly patients with intermittent claudication limited by osteoarticular disorders - feasibility and effectiveness of a low-intensity programme.

PubMed

Lamberti, Nicola; Straudi, Sofia; Lissia, Efisio; Cavazzini, Lorenza; Buja, Sergio; Manfredini, Roberto; Basaglia, Nino; Manfredini, Fabio

2018-04-01

Peripheral arterial disease (PAD) is a common cardiovascular pathology affecting mobility in elderly. Osteoarticular diseases (ODs), responsible for functional limitations and confounding leg symptoms, may interfere with exercise therapy. This study evaluates the feasibility and effectiveness of a structured home-based exercise programme on rehabilitative outcomes in a cohort of elderly PAD patients with and without coexisting ODs. Patients were enrolled from 2002 to 2016 in an exercise programme prescribed and controlled at the hospital and based on two daily 10-minute home walking sessions below the self-selected speed. The presence and localization of ODs at baseline were derived from consultation of medical documents. The ankle-brachial index and functional outcomes, defined as speed at the onset of claudication and attainable maximal speed by an incremental treadmill test, were assessed at baseline and discharge. Feasibility was determined according to dropout rate, number of visits, duration of the programme, and adherence. A total of 1,251 PAD patients were enrolled (931 men; 71 ± 9 years; 0.63 ± 0.19 ankle-brachial index). Eight hundred sixty-four patients were free of ODs (ODfree PAD , 69 %), whereas 387 were affected by ODs (OD PAD , 31 %), predominantly located in the spine (72 %). In the logistic regression models, the presence of ODs was associated with female sex, overweight, sedentary and/or driving professions. At discharge, OD PAD and ODfree PAD did not differ in dropout rates (12 % each), programme duration (378 ± 241 vs. 390 ± 260 days), number of visits (7 ± 3 each), and adherence (80 % each). Similar improvements for OD PAD and ODfree PAD were observed for the ankle-brachial index (0.06 ± 0.12 each), the speed at onset of claudication (0.7 ± 0.7 vs. 0.7 ± 0.8 kmh-1; p = 0.70), and maximal speed (0.4 ± 0.6 vs. 0.4 ± 0.6 kmh-1; p = 0.77). Equally satisfactory rehabilitative outcomes were observed in elderly patients with claudication limited by ODs who completed a well-tolerated, low-impact structured exercise programme.

Environmental enrichment accelerates ocular dominance plasticity in mouse visual cortex whereas transfer to standard cages resulted in a rapid loss of increased plasticity.

PubMed

Kalogeraki, Evgenia; Pielecka-Fortuna, Justyna; Löwel, Siegrid

2017-01-01

In standard cage (SC) raised mice, experience-dependent ocular dominance (OD) plasticity in the primary visual cortex (V1) rapidly declines with age: in postnatal day 25-35 (critical period) mice, 4 days of monocular deprivation (MD) are sufficient to induce OD-shifts towards the open eye; thereafter, 7 days of MD are needed. Beyond postnatal day 110, even 14 days of MD failed to induce OD-plasticity in mouse V1. In contrast, mice raised in a so-called "enriched environment" (EE), exhibit lifelong OD-plasticity. EE-mice have more voluntary physical exercise (running wheels), and experience more social interactions (bigger housing groups) and more cognitive stimulation (regularly changed labyrinths or toys). Whether experience-dependent shifts of V1-activation happen faster in EE-mice and how long the plasticity promoting effect would persist after transferring EE-mice back to SCs has not yet been investigated. To this end, we used intrinsic signal optical imaging to visualize V1-activation i) before and after MD in EE-mice of different age groups (from 1-9 months), and ii) after transferring mice back to SCs after postnatal day 130. Already after 2 days of MD, and thus much faster than in SC-mice, EE-mice of all tested age groups displayed a significant OD-shift towards the open eye. Transfer of EE-mice to SCs immediately abolished OD-plasticity: already after 1 week of SC-housing and MD, OD-shifts could no longer be visualized. In an attempt to rescue abolished OD-plasticity of these mice, we either administered the anti-depressant fluoxetine (in drinking water) or supplied a running wheel in the SCs. OD-plasticity was only rescued for the running wheel- mice. Altogether our results show that raising mice in less deprived environments like large EE-cages strongly accelerates experience-dependent changes in V1-activation compared to the impoverished SC-raising. Furthermore, preventing voluntary physical exercise of EE-mice in adulthood immediately precludes OD-shifts in V1.

Environmental enrichment accelerates ocular dominance plasticity in mouse visual cortex whereas transfer to standard cages resulted in a rapid loss of increased plasticity

PubMed Central

Pielecka-Fortuna, Justyna; Löwel, Siegrid

2017-01-01

In standard cage (SC) raised mice, experience-dependent ocular dominance (OD) plasticity in the primary visual cortex (V1) rapidly declines with age: in postnatal day 25–35 (critical period) mice, 4 days of monocular deprivation (MD) are sufficient to induce OD-shifts towards the open eye; thereafter, 7 days of MD are needed. Beyond postnatal day 110, even 14 days of MD failed to induce OD-plasticity in mouse V1. In contrast, mice raised in a so-called “enriched environment” (EE), exhibit lifelong OD-plasticity. EE-mice have more voluntary physical exercise (running wheels), and experience more social interactions (bigger housing groups) and more cognitive stimulation (regularly changed labyrinths or toys). Whether experience-dependent shifts of V1-activation happen faster in EE-mice and how long the plasticity promoting effect would persist after transferring EE-mice back to SCs has not yet been investigated. To this end, we used intrinsic signal optical imaging to visualize V1-activation i) before and after MD in EE-mice of different age groups (from 1–9 months), and ii) after transferring mice back to SCs after postnatal day 130. Already after 2 days of MD, and thus much faster than in SC-mice, EE-mice of all tested age groups displayed a significant OD-shift towards the open eye. Transfer of EE-mice to SCs immediately abolished OD-plasticity: already after 1 week of SC-housing and MD, OD-shifts could no longer be visualized. In an attempt to rescue abolished OD-plasticity of these mice, we either administered the anti-depressant fluoxetine (in drinking water) or supplied a running wheel in the SCs. OD-plasticity was only rescued for the running wheel- mice. Altogether our results show that raising mice in less deprived environments like large EE-cages strongly accelerates experience-dependent changes in V1-activation compared to the impoverished SC-raising. Furthermore, preventing voluntary physical exercise of EE-mice in adulthood immediately precludes OD-shifts in V1. PMID:29073219

Bacterial community shift during the startup of a full-scale oxidation ditch treating sewage.

PubMed

Chen, Yajun; Ye, Lin; Zhao, Fuzheng; Xiao, Lin; Cheng, Shupei; Zhang, Xu-Xiang

2016-10-06

Oxidation ditch (OD) is one of the most widely used processes for treating municipal wastewater. However, the microbial communities in the OD systems have not been well characterized and little information about the shift of bacterial community during the startup process of the OD systems is available. In this study, we investigated the bacterial community changes during the startup period (over 100 days) of a full-scale OD. The results showed that the bacterial community dramatically changed during the startup period. Similar to the activated sludge samples in other studies, Proteobacteria (accounting for 26.3%~48.4%) was the most dominant bacterial phylum in the OD system but its relative abundance declined nearly 40% during the startup process. It was also found that Planctomycetes proliferated greatly (from 4.79% to 13.5%) and finally replaced Bacteroidetes as the second abundant phylum in the OD system. Specifically, some bacteria affiliated with Flavobacterium genus of exhibited remarkable decreasing trends, while bacterial species belonging to OD1 candidate division and Saprospiraceae family were found to increase during the startup process. Despite of the bacterial community shift, the organic matter, nitrogen and phosphorus in the effluent were always in low concentrations, suggesting the functional redundancy of the bacterial community. Moreover, by comparing with the bacterial community in other municipal wastewater treatment bioreactors, some potentially novel bacterial species were found to be present in the OD system. Collectively, this study improved our understandings of bacterial community structure and the microbial ecology during the startup of full-scale wastewater treatment bioreactor.

Protective factors can mitigate behavior problems after prenatal cocaine and other drug exposures.

PubMed

Bada, Henrietta S; Bann, Carla M; Whitaker, Toni M; Bauer, Charles R; Shankaran, Seetha; Lagasse, Linda; Lester, Barry M; Hammond, Jane; Higgins, Rosemary

2012-12-01

We determined the role of risk and protective factors on the trajectories of behavior problems associated with high prenatal cocaine exposure (PCE)/polydrug exposure. The Maternal Lifestyle Study enrolled 1388 children with or without PCE, assessed through age 15 years. Because most women using cocaine during pregnancy also used other substances, we analyzed for the effects of 4 categories of prenatal drug exposure: high PCE/other drugs (OD), some PCE/OD, OD/no PCE, and no PCE/no OD. Risks and protective factors at individual, family, and community levels that may be associated with behavior outcomes were entered stepwise into latent growth curve models, then replaced by cumulative risk and protective indexes, and finally by a combination of levels of risk and protective indexes. Main outcome measures were the trajectories of externalizing, internalizing, total behavior, and attention problems scores from the Child Behavior Checklist (parent). A total of 1022 (73.6%) children had known outcomes. High PCE/OD significantly predicted externalizing, total, and attention problems when considering the balance between risk and protective indexes. Some PCE/OD predicted externalizing and attention problems. OD/no PCE also predicted behavior outcomes except for internalizing behavior. High level of protective factors was associated with declining trajectories of problem behavior scores over time, independent of drug exposure and risk index scores. High PCE/OD is a significant risk for behavior problems in adolescence; protective factors may attenuate its detrimental effects. Clinical practice and public health policies should consider enhancing protective factors while minimizing risks to improve outcomes of drug-exposed children.

Occupational Dermatoses by Type of Work in Greece

PubMed Central

Zorba, Eleni; Karpouzis, Antony; Zorbas, Alexandros; Bazas, Theodore; Zorbas, Sam; Alexopoulos, Elias; Zorbas, Ilias; Kouskoukis, Konstantinos; Konstandinidis, Theodoros

2013-01-01

Background To elucidate the relationship between seven occupational dermatoses (ODs) and 20 types of work in Greece. Methods This was a prevalence epidemiologic study of certain ODs among 4,000 workers employed in 20 types of enterprise, in 104 companies, in 2006–2012, using data from company medical records, questionnaires, occupational medical, and special examinations. The χ2 test was applied to reveal statistically significant relationships between types of enterprises and occurrence of ODs. Results A high percentage (39.9%) of employees included in the study population suffered from ODs. The highest prevalence rates were noted among hairdressers (of contact dermatitis: 30%), cooks (of contact dermatitis: 29.5%), bitumen workers (of acne: 23.5%), car industry workers (of mechanical injury: 15%), construction workers (of contact urticaria: 29.5%), industrial cleaning workers (of chemical burns: 13%), and farmers (of malignant tumors: 5.5%). We observed several statistical significant correlations between ODs (acute and chronic contact dermatitis, urticaria, mechanical injury, acne, burns, skin cancer) and certain types of enterprises. There was no statistically significant correlation between gender and prevalence of ODs, except for dermatoses caused by mechanical injuries afflicting mainly men [χ2 (1) = 13.40, p < 0.001] and for chronic contact dermatitis [χ2 (1) = 5.53, p = 0.019] afflicting mainly women. Conclusion Prevalence of ODs is high in Greece, contrary to all official reports by the Greek National Institute of Health. There is a need to introduce a nationwide voluntary surveillance system for reporting ODs and to enhance skin protection measures at work. PMID:24106644

Internal Delorme's Procedure for Treating ODS Associated With Impaired Anal Continence.

PubMed

Liu, Weicheng; Sturiale, Alessandro; Fabiani, Bernardina; Giani, Iacopo; Menconi, Claudia; Naldini, Gabriele

2017-12-01

The aim of this study was to evaluate the medium-term outcomes of internal Delorme's procedure for treating obstructed defecation syndrome (ODS) patients with impaired anal continence. In a retrospective study, 41 ODS patients who underwent internal Delorme's procedure between 2011 and 2015 were divided into 3 subgroups according to their associated symptoms of impaired continence, as urgency, passive fecal incontinence and both, before study. Then the patients' preoperative statuses, perioperative complications, and postoperative outcomes were investigated and collected from standardized questionnaires, including Altomare ODS score, Fecal Incontinence Severity Index (FISI), Patient Assessment of Constipation-Quality of Life Questionnaire (PAC-QoL), and Fecal Incontinence Quality of Life Scale (FIQLS). All results with a 2-tailed P < .05 were considered statistically significant. At an average 2.8 years of follow-up, there were significant improvements ( P < .01) in Altomare ODS score, FISI, PAC-QoL, and FIQLS in all patients when comparing scores from before the operation with those at the final follow-up. Similar results were also observed in both the urgency subgroup and passive fecal incontinence subgroup, but there were no statistically significant improvements ( P > .05) in Altomare ODS score, FISI, PAC-QoL, or FIQLS in the urgency and passive fecal incontinence subgroups. Anorectal manometry showed the mean value of anal resting pressure increased 20%. Additionally, no major complications occurred. Internal Delorme's procedure is effective without major morbidity for treating ODS associated with urgency or passive fecal incontinence, but it may be less effective for treating ODS associated with both urgency and passive fecal incontinence.

Prevalence of pelvic floor symptoms in female patients attending the two-week wait clinic with suspected colorectal cancer.

PubMed

Bennett, J; Greenwood, A; Durdey, P; Glancy, D

2016-07-01

Introduction The aim of this study was to establish the prevalence of pelvic floor symptoms in women referred to a colorectal two-week wait (2WW) clinic with suspected colorectal cancer. Methods A questionnaire assessing faecal incontinence (FI) (Wexner score) and obstructed defecation syndrome (ODS) (Renzi score) was offered to 98 consecutive female patients attending a colorectal 2WW clinic at a single trust. Results Overall, 56 (57%) of the 98 patients had significant ODS and/or FI (scores >9/20), 33 (34%) had ODS and 40 (41%) had FI. Seventeen patients (17%) had both ODS and FI. Analysis of the 63 patients referred with a change in bowel habit (CIBH) showed 40 (63%) to be Renzi and/or Wexner positive compared with 16 (46%) of the 35 patients who presented without CIBH (p=0.095, Fisher's exact test). Further analysis showed that 31 (78%) of the 40 patients with FI presented with CIBH compared with 32 (55%) of the 58 without FI (p=0.032). In terms of ODS, 23 (70%) of the 33 patients with ODS presented with CIBH compared with 40 (62%) of the 65 without ODS (p=0.506). Conclusions Over half of the female patients attending our colorectal 2WW clinic had significant pelvic floor dysfunction (FI/ODS), which may account for their symptoms (especially in the CIBH referral category). While it is important for malignancy to be excluded, many patients may benefit from investigation and management of their pelvic floor dysfunction as the cause for their presenting symptoms.

Occupational dermatoses by type of work in Greece.

PubMed

Zorba, Eleni; Karpouzis, Antony; Zorbas, Alexandros; Bazas, Theodore; Zorbas, Sam; Alexopoulos, Elias; Zorbas, Ilias; Kouskoukis, Konstantinos; Konstandinidis, Theodoros

2013-09-01

To elucidate the relationship between seven occupational dermatoses (ODs) and 20 types of work in Greece. This was a prevalence epidemiologic study of certain ODs among 4,000 workers employed in 20 types of enterprise, in 104 companies, in 2006-2012, using data from company medical records, questionnaires, occupational medical, and special examinations. The χ(2) test was applied to reveal statistically significant relationships between types of enterprises and occurrence of ODs. A high percentage (39.9%) of employees included in the study population suffered from ODs. The highest prevalence rates were noted among hairdressers (of contact dermatitis: 30%), cooks (of contact dermatitis: 29.5%), bitumen workers (of acne: 23.5%), car industry workers (of mechanical injury: 15%), construction workers (of contact urticaria: 29.5%), industrial cleaning workers (of chemical burns: 13%), and farmers (of malignant tumors: 5.5%). We observed several statistical significant correlations between ODs (acute and chronic contact dermatitis, urticaria, mechanical injury, acne, burns, skin cancer) and certain types of enterprises. There was no statistically significant correlation between gender and prevalence of ODs, except for dermatoses caused by mechanical injuries afflicting mainly men [χ(2) (1) = 13.40, p < 0.001] and for chronic contact dermatitis [χ(2) (1) = 5.53, p = 0.019] afflicting mainly women. Prevalence of ODs is high in Greece, contrary to all official reports by the Greek National Institute of Health. There is a need to introduce a nationwide voluntary surveillance system for reporting ODs and to enhance skin protection measures at work.

77 FR 5193 - Retrospective Review Under E.O. 13563: Shipping-Removal of Obsolete Regulations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-02

... Program, which replaced the Operating-Differential Subsidy (ODS) Program. Therefore, the regulations pertaining to the ODS Program and the Construction-Differential (CDS) Program are no longer in use. In... regulations 46 CFR parts 251, 252, 276, 280, 281,282, and 283. The regulations related to the ODS Program are...

46 CFR 280.11 - Example of calculation and sample report.

Code of Federal Regulations, 2010 CFR

2010-10-01

... subsidized under an ODS agreement made in accordance with § 280.3. Total annual subsidy payable for Company A... carriage of competitive cargo. Accordingly, total ODS payable to Company A for voyages terminated during... of service ODS payable $400,000 (Outbound freight revenue, $4 million, divided by total gross revenue...

Irradiation creep and microstructural changes in an advanced ODS ferritic steel during helium implantation under stress

NASA Astrophysics Data System (ADS)

Chen, J.; Pouchon, M. A.; Kimura, A.; Jung, P.; Hoffelner, W.

2009-04-01

An advanced oxide dispersion strengthened (ODS) ferritic steel with very fine oxide particles has been homogeneously implanted with helium under uniaxial tensile stresses from 20 to 250 MPa to a maximum dose of about 0.38 dpa (1650 appm-He) with displacement damage rates of 4.4 × 10 -6 dpa/s at temperatures of 573 and 773 K. The samples were in the form of miniaturized dog-bones, where during the helium implantation the straining and the electrical resistance were monitored simultaneously. Creep compliances were measured to be 4.0 × 10 -6 and 11 × 10 -6 dpa -1 MPa -1 at 573 and 773 K, respectively. The resistivity of ODS steel samples decreased with dose, indicating segregation and/or precipitation. Evolution of microstructure during helium implantation was studied in detail by TEM. The effects of ODS particle size on irradiation creep and microstructural changes was investigated by comparing the results from the present advanced ODS (K1) to a commercial ODS ferritic steels (PM2000) with much bigger oxide particles.

Comparison of a polymeric pseudostationary phase in EKC with ODS stationary phase in RP-HPLC.

PubMed

Ni, Xinjiong; Zhang, Min; Xing, Xiaoping; Cao, Yuhua; Cao, Guangqun

2018-01-01

Poly(stearyl methacrylate-co-methacrylic acid) (P(SMA-co-MAA)) was induced as pseudostationary phase (PSP) in electrokinetic chromatography (EKC). The n-octadecyl groups in SMA were the same as that in octadecylsilane (ODS) C18 column. Thus, the present work focused on the comparison of selectivity between polymeric PSP and ODS stationary phase (SP), and the effect of organic modifiers on the selectivity of polymeric PSP and ODS SP. 1-butanol could directly interacted with PSP as a Class I modifier, and improved both of the methylene selectivity and polar group selectivity. When the analysis times were similar, the polymeric PSP exhibited better methylene selectivity and polar group selectivity. Although the hydrophobic groups were similar, the substituted benzenes elution order was different between polymeric PSP and ODS SP. Linear solvation energy relationships (LSER) model analysis found that polymeric PSP and ODS SP exhibited two same key factors in selectivity: hydrophobic interaction and hydrogen bonding acidity. But polymeric PSP exhibited relatively strong n- and π-electrons interaction to the analytes. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quantitative isotopic measurements of gas-phase alcohol mixtures using a broadly tunable swept external cavity quantum cascade laser

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

Brumfield, B. E.; Phillips, M. C.

A swept-ECQCL is used for broadband IR spectroscopy of isotopic mixtures of CH3OH, CH3OD, CH3CH2OH, and CH3CH2OD in a static gas cell over a wavelength range of 9.5 to 10.4 µm. A weighted least squares fitting approach with quantitative library spectra illustrates that significant spectral congestion does not negatively impact the ability for in situ quantification of large isotopic species in a mixture. The noise equivalent concentrations for CH3OH, CH3OD, CH3CH2OH, and CH3CH2OD are 19 ppbv x m, 28 ppbv x m, 450 ppbv x m, and 330 ppbv x m respectively for a 50 second integration time. Based onmore » the observed NECs, isotopic precisions of 0.07‰ and 0.79‰ for a 50 s integration time are calculated for measurements of the [MeOD]/[MeOH] and [EtOD]/[EtOH] isotope ratios , respectively, for the species concentrations in the gas cell.« less

Flight dynamics facility operational orbit determination support for the ocean topography experiment

NASA Technical Reports Server (NTRS)

Bolvin, D. T.; Schanzle, A. F.; Samii, M. V.; Doll, C. E.

1991-01-01

The Ocean Topography Experiment (TOPEX/POSEIDON) mission is designed to determine the topography of the Earth's sea surface across a 3 yr period, beginning with launch in June 1992. The Goddard Space Flight Center Dynamics Facility has the capability to operationally receive and process Tracking and Data Relay Satellite System (TDRSS) tracking data. Because these data will be used to support orbit determination (OD) aspects of the TOPEX mission, the Dynamics Facility was designated to perform TOPEX operational OD. The scientific data require stringent OD accuracy in navigating the TOPEX spacecraft. The OD accuracy requirements fall into two categories: (1) on orbit free flight; and (2) maneuver. The maneuver OD accuracy requirements are of two types; premaneuver planning and postmaneuver evaluation. Analysis using the Orbit Determination Error Analysis System (ODEAS) covariance software has shown that, during the first postlaunch mission phase of the TOPEX mission, some postmaneuver evaluation OD accuracy requirements cannot be met. ODEAS results also show that the most difficult requirements to meet are those that determine the change in the components of velocity for postmaneuver evaluation.

Detecting the optic disc boundary in digital fundus images using morphological, edge detection, and feature extraction techniques.

PubMed

Aquino, Arturo; Gegundez-Arias, Manuel Emilio; Marin, Diego

2010-11-01

Optic disc (OD) detection is an important step in developing systems for automated diagnosis of various serious ophthalmic pathologies. This paper presents a new template-based methodology for segmenting the OD from digital retinal images. This methodology uses morphological and edge detection techniques followed by the Circular Hough Transform to obtain a circular OD boundary approximation. It requires a pixel located within the OD as initial information. For this purpose, a location methodology based on a voting-type algorithm is also proposed. The algorithms were evaluated on the 1200 images of the publicly available MESSIDOR database. The location procedure succeeded in 99% of cases, taking an average computational time of 1.67 s. with a standard deviation of 0.14 s. On the other hand, the segmentation algorithm rendered an average common area overlapping between automated segmentations and true OD regions of 86%. The average computational time was 5.69 s with a standard deviation of 0.54 s. Moreover, a discussion on advantages and disadvantages of the models more generally used for OD segmentation is also presented in this paper.

High resolution SEM characterization of nano-precipitates in ODS steels.

PubMed

Jóźwik, Iwona; Strojny-Nędza, Agata; Chmielewski, Marcin; Pietrzak, Katarzyna; Kurpaska, Łukasz; Nosewicz, Szymon

2018-05-01

The performance of the present-day scanning electron microscopy (SEM) extends far beyond delivering electronic images of the surface topography. Oxide dispersion strengthened (ODS) steel is on of the most promising materials for the future nuclear fusion reactor because of its good radiation resistance, and higher operation temperature up to 750°C. The microstructure of ODS should not exceed tens of nm, therefore there is a strong need in a fast and reliable technique for their characterization. In this work, the results of low-kV SEM characterization of nanoprecipitates formed in the ODS matrix are presented. Application of highly sensitive photo-diode BSE detector in SEM imaging allowed for the registration of single nm-sized precipitates in the vicinity of the ODS alloys. The composition of the precipitates has been confirmed by TEM-EDS. © 2018 Wiley Periodicals, Inc.

Corrigendum to 'On the influence of microstructure on the fracture behaviour of hot extruded ferritic ODS steels' [J. Nucl. Mater. 497 (2017) 60-75

NASA Astrophysics Data System (ADS)

Das, A.; Viehrig, H. W.; Altstadt, E.; Heintze, C.; Hoffmann, J.

2018-02-01

ODS steels are known to show inferior fracture properties as compared to ferritic martensitic non-ODS steels. Hot extruded 13Cr ODS steel however, showed excellent fracture toughness at a temperature range from room temperature to 400 °C. In this work, the factors which resulted in superior and anisotropic fracture behaviour were investigated by comparing different orientations of two hot extruded materials using scanning electron, electron backscatter and transmission electron microscopy. Fracture behaviour of the two materials was compared using unloading compliance fracture toughness tests. Anisotropic fracture toughness was predominantly influenced by grain morphology. Superior fracture toughness in 13Cr ODS-KIT was predominantly influenced by factors such as smaller void inducing particle size and higher sub-micron particle-matrix interfacial strength.

Recent progresses in outcome-dependent sampling with failure time data.

PubMed

Ding, Jieli; Lu, Tsui-Shan; Cai, Jianwen; Zhou, Haibo

2017-01-01

An outcome-dependent sampling (ODS) design is a retrospective sampling scheme where one observes the primary exposure variables with a probability that depends on the observed value of the outcome variable. When the outcome of interest is failure time, the observed data are often censored. By allowing the selection of the supplemental samples depends on whether the event of interest happens or not and oversampling subjects from the most informative regions, ODS design for the time-to-event data can reduce the cost of the study and improve the efficiency. We review recent progresses and advances in research on ODS designs with failure time data. This includes researches on ODS related designs like case-cohort design, generalized case-cohort design, stratified case-cohort design, general failure-time ODS design, length-biased sampling design and interval sampling design.

Recent progresses in outcome-dependent sampling with failure time data

PubMed Central

Ding, Jieli; Lu, Tsui-Shan; Cai, Jianwen; Zhou, Haibo

2016-01-01

An outcome-dependent sampling (ODS) design is a retrospective sampling scheme where one observes the primary exposure variables with a probability that depends on the observed value of the outcome variable. When the outcome of interest is failure time, the observed data are often censored. By allowing the selection of the supplemental samples depends on whether the event of interest happens or not and oversampling subjects from the most informative regions, ODS design for the time-to-event data can reduce the cost of the study and improve the efficiency. We review recent progresses and advances in research on ODS designs with failure time data. This includes researches on ODS related designs like case–cohort design, generalized case–cohort design, stratified case–cohort design, general failure-time ODS design, length-biased sampling design and interval sampling design. PMID:26759313

Detection of OD towards the low-mass protostar IRAS 16293-2422

NASA Astrophysics Data System (ADS)

Parise, B.; Du, F.; Liu, F.-C.; Belloche, A.; Wiesemeyer, H.; Güsten, R.; Menten, K. M.; Hübers, H.-W.; Klein, B.

2012-06-01

Context. Although water is an essential and widespread molecule in star-forming regions, its chemical formation pathways are still not very well constrained. Observing the level of deuterium fractionation of OH, a radical involved in the water chemical network, is a promising way to infer its chemical origin. Aims: We aim at understanding the formation mechanisms of water by investigating the origin of its deuterium fractionation. This can be achieved by observing the abundance of OD towards the low-mass protostar IRAS 16293-2422, where the HDO distribution is already known. Methods: Using the GREAT receiver on board SOFIA, we observed the ground-state OD transition at 1391.5 GHz towards the low-mass protostar IRAS 16293-2422. We also present the detection of the HDO 111-000 line using the APEX telescope. We compare the OD/HDO abundance ratio inferred from these observations with the predictions of chemical models. Results: The OD line is detected in absorption towards the source continuum. This is the first detection of OD outside the solar system. The SOFIA observation, coupled to the observation of the HDO 111-000 line, provides an estimate of the abundance ratio OD/HDO ~ 17-90 in the gas where the absorption takes place. This value is fairly high compared with model predictions. This may be reconciled if reprocessing in the gas by means of the dissociative recombination of H2DO+ further fractionates OH with respect to water. Conclusions: The present observation demonstrates the capability of the SOFIA/GREAT instrument to detect the ground transition of OD towards star-forming regions in a frequency range that was not accessible before. Dissociative recombination of H2DO+ may play an important role in setting a high OD abundance. Measuring the branching ratios of this reaction in the laboratory will be of great value for chemical models. Figure 5 is available in electronic form at http://www.aanda.org

Activity-Based Protein Profiling of Ammonia Monooxygenase in Nitrosomonas europaea

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

Bennett, Kristen; Sadler, Natalie C.; Wright, Aaron T.

Nitrosomonas europaeais an aerobic nitrifying bacterium that oxidizes ammonia (NH 3) to nitrite (NO 2 ₋) through the sequential activities of ammonia monooxygenase (AMO) and hydroxylamine dehydrogenase (HAO). Many alkynes are mechanism-based inactivators of AMO, and here we describe an activity-based protein profiling method for this enzyme using 1,7-octadiyne (17OD) as a probe. Inactivation of NH 4 +-dependent O 2uptake byN. europaeaby 17OD was time- and concentration-dependent. The effects of 17OD were specific for ammonia-oxidizing activity, andde novoprotein synthesis was required to reestablish this activity after cells were exposed to 17OD. Cells were reacted with Alexa Fluor 647 azide usingmore » a copper-catalyzed azide-alkyne cycloaddition (CuAAC) (click) reaction, solubilized, and analyzed by SDS-PAGE and infrared (IR) scanning. A fluorescent 28-kDa polypeptide was observed for cells previously exposed to 17OD but not for cells treated with either allylthiourea or acetylene prior to exposure to 17OD or for cells not previously exposed to 17OD. The fluorescent polypeptide was membrane associated and aggregated when heated with β-mercaptoethanol and SDS. The fluorescent polypeptide was also detected in cells pretreated with other diynes, but not in cells pretreated with structural homologs containing a single ethynyl functional group. The membrane fraction from 17OD-treated cells was conjugated with biotin-azide and solubilized in SDS. Streptavidin affinity-purified polypeptides were on-bead trypsin-digested, and amino acid sequences of the peptide fragments were determined by liquid chromatography-mass spectrometry (LC-MS) analysis. Peptide fragments from AmoA were the predominant peptides detected in 17OD-treated samples. In-gel digestion and matrix-assisted laser desorption ionization–tandem time of flight (MALDI-TOF/TOF) analyses also confirmed that the fluorescent 28-kDa polypeptide was AmoA.« less

Hydrophilization of Magnetic Nanoparticles with Modified Alternating Copolymers. Part 1: The Influence of the Grafting

PubMed Central

Bronstein, Lyudmila M.; Shtykova, Eleonora V.; Malyutin, Andrey; Dyke, Jason C.; Gunn, Emily; Gao, Xinfeng; Stein, Barry; Konarev, Peter V.; Dragnea, Bogdan; Svergun, Dmitri I.

2010-01-01

Iron oxide nanoparticles (NPs) with a diameter 21.6 nm were coated with poly(maleic acid-alt-1-octadecene) (PMAcOD) modified with grafted 5,000 Da poly(ethyelene glycol) (PEG) or short ethylene glycol (EG) tails. The coating procedure utilizes hydrophobic interactions of octadecene and oleic acid tails, while the hydrolysis of maleic anhydride moieties as well as the presence of hydrophilic PEG (EG) tails allows the NP hydrophilicity. The success of the NP coating was found to be independent of the degree of grafting which was varied between 20 and 80% of the –MacOD-units, but depended on the length of the grafted tail. The NP coating and hydrophilization did not occur when the modified copolymer contained 750 Da PEG tails independently of the grafting degree. To explain this phenomenon the micellization of the modified PMAcOD copolymers in water was analyzed by small angle x-ray scattering (SAXS). The PMAcOD molecules with the grafted 750 Da PEG tails form compact non-interacting disk-like micelles, whose stability apparently allows for no interactions with the NP hydrophobic shells. The PMAcOD containing the 5,000 Da PEG and EG tails form much larger aggregates capable of an efficient coating of the NPs. The coated NPs were characterized using transmission electron microscopy, dynamic light scattering, ζ-potential measurements, and thermal gravimetry analysis. The latter method demonstrated that the presence of long PEG tails in modified PMAcOD allows the attachment of fewer macromolecules (by a factor of ~20) compared to the case of non-modified or EG modified PMAcOD, emphasizing the importance of PEG tails in NP hydrophilization. The NPs coated with PMAcOD modified with 60% (towards all –MAcOD- units) of the 5,000 PEG tails bear a significant negative charge and display good stability in buffers. Such NPs can be useful as magnetic cores for virus-like particle formation. PMID:21221425

Activation and Coagulation Biomarkers are Independent Predictors for the Development of Opportunistic Disease in Patients with HIV Infection

PubMed Central

Rodger, Alison J; Fox, Zoe; Lundgren, Jens D; Kuller, Lew; Boesecke, Christoph; Gey, Daniela; Skoutelis, Athanassios; Goetz, Matthew Bidwell; Phillips, Andrew N

2010-01-01

Background Activation and coagulation biomarkers were measured within the SMART trial. Their associations with opportunistic disease (OD) in HIV-positive patients were examined. Methods Inflammatory (high-sensitivity C-reactive protein [hsCRP], interleukin-6 [IL-6], amyloid-A, and amyloid-P) and coagulation (D-dimer and prothrombin-fragment 1+2) markers were determined. Conditional logistic regression analyses were used to assess associations between these biomarkers and risk of OD. Results The 91 patients who developed an OD were matched to 182 controls. Patients with hsCRP≥5 μg/mL at baseline had a 3.5 (95%CI: 1.5-8.1) higher odds of OD versus those with hsCRP<1 μg/ml, Ptrend=0.003, and patients with IL-6≥3 pg/mL at baseline had a 2.4 (95%CI: 1.0-5.4) higher odds of OD versus those with IL-6<1.5 pg/mL, Ptrend=0.02. No other baseline biomarkers predicted development of an OD. Latest hsCRP (OR: 7.6 (95%CI: 2.0-28.5) for those with hsCRP≥5 μg/mL versus hsCRP<1 μg/mL, Ptrend=0.002), latest amyloid-A (OR: 3.8 (95%CI: 1.1-13.4) for those with amyloid-A ≥6 mg/L versus amyloid-A <2 mg/L, Ptrend=0.03) and latest IL-6 (OR 2.4 (95%CI: 0.7-8.8) for those with IL-6≥3 pg/mL versus IL-6<1.5 pg/mL, Ptrend=0.04) were also associated with developing an OD. Conclusions Higher IL-6 and hsCRP independently predicted development of OD. These biomarkers could provide additional prognostic information for predicting risk of OD. PMID:19678756

Development of ODS FeCrAl alloys for accident-tolerant fuel cladding

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

Dryepondt, Sebastien N.; Hoelzer, David T.; Pint, Bruce A.

2015-09-18

FeCrAl alloys are prime candidates for accident-tolerant fuel cladding due to their excellent oxidation resistance up to 1400 C and good mechanical properties at intermediate temperature. Former commercial oxide dispersion strengthened (ODS) FeCrAl alloys such as PM2000 exhibit significantly better tensile strength than wrought FeCrAl alloys, which would alloy for the fabrication of a very thin (~250 m) ODS FeCrAl cladding and limit the neutronic penalty from the replacement of Zr-based alloys by Fe-based alloys. Several Fe-12-Cr-5Al ODS alloys where therefore fabricated by ball milling FeCrAl powders with Y2O3 and additional oxides such as TiO 2 or ZrO 2. Themore » new Fe-12Cr-5Al ODS alloys showed excellent tensile strength up to 800 C but limited ductility. Good oxidation resistance in steam at 1200 and 1400 C was observed except for one ODS FeCrAl alloy containing Ti. Rolling trials were conducted at 300, 600 C and 800 C to simulate the fabrication of thin tube cladding and a plate thickness of ~0.6mm was reached before the formation of multiple edge cracks. Hardness measurements at different stages of the rolling process, before and after annealing for 1h at 1000 C, showed that a thinner plate thickness could likely be achieved by using a multi-step approach combining warm rolling and high temperature annealing. Finally, new Fe-10-12Cr-5.5-6Al-Z gas atomized powders have been purchased to fabricate the second generation of low-Cr ODS FeCrAl alloys. The main goals are to assess the effect of O, C, N and Zr contents on the ODS FeCrAl microstructure and mechanical properties, and to optimize the fabrication process to improve the ductility of the 2nd gen ODS FeCrAl while maintaining good mechanical strength and oxidation resistance.« less

Evaluating the Good Ontology Design Guideline (GoodOD) with the Ontology Quality Requirements and Evaluation Method and Metrics (OQuaRE)

PubMed Central

Duque-Ramos, Astrid; Boeker, Martin; Jansen, Ludger; Schulz, Stefan; Iniesta, Miguela; Fernández-Breis, Jesualdo Tomás

2014-01-01

Objective To (1) evaluate the GoodOD guideline for ontology development by applying the OQuaRE evaluation method and metrics to the ontology artefacts that were produced by students in a randomized controlled trial, and (2) informally compare the OQuaRE evaluation method with gold standard and competency questions based evaluation methods, respectively. Background In the last decades many methods for ontology construction and ontology evaluation have been proposed. However, none of them has become a standard and there is no empirical evidence of comparative evaluation of such methods. This paper brings together GoodOD and OQuaRE. GoodOD is a guideline for developing robust ontologies. It was previously evaluated in a randomized controlled trial employing metrics based on gold standard ontologies and competency questions as outcome parameters. OQuaRE is a method for ontology quality evaluation which adapts the SQuaRE standard for software product quality to ontologies and has been successfully used for evaluating the quality of ontologies. Methods In this paper, we evaluate the effect of training in ontology construction based on the GoodOD guideline within the OQuaRE quality evaluation framework and compare the results with those obtained for the previous studies based on the same data. Results Our results show a significant effect of the GoodOD training over developed ontologies by topics: (a) a highly significant effect was detected in three topics from the analysis of the ontologies of untrained and trained students; (b) both positive and negative training effects with respect to the gold standard were found for five topics. Conclusion The GoodOD guideline had a significant effect over the quality of the ontologies developed. Our results show that GoodOD ontologies can be effectively evaluated using OQuaRE and that OQuaRE is able to provide additional useful information about the quality of the GoodOD ontologies. PMID:25148262

Transdermal skin patch based on reduced graphene oxide: A new approach for photothermal triggered permeation of ondansetron across porcine skin.

PubMed

Teodorescu, Florina; Quéniat, Gurvan; Foulon, Catherine; Lecoeur, Marie; Barras, Alexandre; Boulahneche, Samia; Medjram, Mohmaed Salah; Hubert, Thomas; Abderrahmani, Amar; Boukherroub, Rabah; Szunerits, Sabine

2017-01-10

The development of a skin-mounted patch capable of controlled transcutaneous delivery of therapeutics through thermal activation provides a unique solution for the controlled release of active principles over long-term periods. Here, we report on a flexible transdermal patch for photothermal triggered release of ondansetron (ODS), a commonly used drug for the treatment of chemotherapy-induced nausea and vomiting and used as model compound here. To achieve this, a dispersion of ODS-loaded reduced graphene oxide (rGO-ODS) nanosheets were deposited onto Kapton to produce a flexible polyimide-based patch. It is demonstrated that ODS loaded Kapton/rGO patches have a high drug delivery performance upon irradiation with a continuous laser beam at 980nm for 10min due to an induced photothermal heating effect. The ability of ODS impregnated Kapton/rGO patches as transdermal delivery scaffolds for ODS across the skin is in addition investigated using porcine ear skin as a model. We show that the cumulative quantity and flux of ODS passing the skin are highly depending on the laser power density used. At 5Wcm -2 irradiation, the ODS flux across pig skin was determined to be 1.6μgcm -2 h -1 comparable to other approaches. The use of tween 20 as skin enhancer could significantly increase the ODS flux to 13.2μgcm -2 h -1 . While the skin penetration enhancement is comparable to that obtained using other well-known permeation enhancers, the actual superiority and interest of the proposed approach is that the Kapton/rGO photoactivatable skin patch can be loaded with any drugs and therapeutics of interest, making the approach extremely versatile. The on demand delivery of drugs upon local laser irradiation and the possibility to reload the interface with the drug makes this new drug administration route very appealing. Copyright © 2016 Elsevier B.V. All rights reserved.

Evaluating the Good Ontology Design Guideline (GoodOD) with the ontology quality requirements and evaluation method and metrics (OQuaRE).

PubMed

Duque-Ramos, Astrid; Boeker, Martin; Jansen, Ludger; Schulz, Stefan; Iniesta, Miguela; Fernández-Breis, Jesualdo Tomás

2014-01-01

To (1) evaluate the GoodOD guideline for ontology development by applying the OQuaRE evaluation method and metrics to the ontology artefacts that were produced by students in a randomized controlled trial, and (2) informally compare the OQuaRE evaluation method with gold standard and competency questions based evaluation methods, respectively. In the last decades many methods for ontology construction and ontology evaluation have been proposed. However, none of them has become a standard and there is no empirical evidence of comparative evaluation of such methods. This paper brings together GoodOD and OQuaRE. GoodOD is a guideline for developing robust ontologies. It was previously evaluated in a randomized controlled trial employing metrics based on gold standard ontologies and competency questions as outcome parameters. OQuaRE is a method for ontology quality evaluation which adapts the SQuaRE standard for software product quality to ontologies and has been successfully used for evaluating the quality of ontologies. In this paper, we evaluate the effect of training in ontology construction based on the GoodOD guideline within the OQuaRE quality evaluation framework and compare the results with those obtained for the previous studies based on the same data. Our results show a significant effect of the GoodOD training over developed ontologies by topics: (a) a highly significant effect was detected in three topics from the analysis of the ontologies of untrained and trained students; (b) both positive and negative training effects with respect to the gold standard were found for five topics. The GoodOD guideline had a significant effect over the quality of the ontologies developed. Our results show that GoodOD ontologies can be effectively evaluated using OQuaRE and that OQuaRE is able to provide additional useful information about the quality of the GoodOD ontologies.

Incidence rates of occupational diseases in the Dutch construction sector, 2010-2014.

PubMed

van der Molen, Henk F; de Vries, Sanne C; Stocks, S Jill; Warning, Jan; Frings-Dresen, Monique H W

2016-05-01

To estimate incidence and trends in incidence of occupational diseases (ODs) in the Dutch construction sector. In a dynamic prospective cohort over a 5-year period (2010-2014), ODs assessed by occupational physicians (OPs) participating in a voluntary construction workers health surveillance (WHS) were reported to the Netherlands Centre for Occupational Diseases (NCOD). ODs were defined as a disease with a specific clinical diagnosis (International Classification of Diseases) that was predominantly caused by work-related factors as assessed by an OP. Annual incidences were determined for the total number of ODs and six frequently occurring OD groups. Trends in incidence were estimated using a multilevel negative binominal regression model. In 2014 the incidence of all OD was 12 964 per 100 000 workers and there was no significant change in incidence between 2010 and 2014 (3%; 95% CI -2% to +9%). Hearing loss (8125 per 100 000 workers) and musculoskeletal disorders (2081 per 100 000 workers) were the most frequently occurring ODs. Noise-induced hearing loss (+7%; 95% CI 1% to 13%) and contact dermatitis (+19%; 95% CI 6% to 33%) showed increasing trends. There was no statistically significant change in the incidence of low back pain, arthrosis, repetitive strain injuries, distress/burnout and chronic obstructive pulmonary disease/asthma. In total, 13% of workers participating in WHS in the Dutch construction industry during 2014 had an OD diagnosed and reported by an OP. Over a 5-year period the annual incidence of reported ODs showed a statistically non-significant increase. Incidences in noise-induced hearing loss and contact dermatitis showed statistically significant increasing trends, 7% and 19%, respectively. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Activity-Based Protein Profiling of Ammonia Monooxygenase in Nitrosomonas europaea

PubMed Central

Bennett, Kristen; Sadler, Natalie C.; Wright, Aaron T.; Yeager, Chris

2016-01-01

Nitrosomonas europaea is an aerobic nitrifying bacterium that oxidizes ammonia (NH3) to nitrite (NO2−) through the sequential activities of ammonia monooxygenase (AMO) and hydroxylamine dehydrogenase (HAO). Many alkynes are mechanism-based inactivators of AMO, and here we describe an activity-based protein profiling method for this enzyme using 1,7-octadiyne (17OD) as a probe. Inactivation of NH4+-dependent O2 uptake by N. europaea by 17OD was time- and concentration-dependent. The effects of 17OD were specific for ammonia-oxidizing activity, and de novo protein synthesis was required to reestablish this activity after cells were exposed to 17OD. Cells were reacted with Alexa Fluor 647 azide using a copper-catalyzed azide-alkyne cycloaddition (CuAAC) (click) reaction, solubilized, and analyzed by SDS-PAGE and infrared (IR) scanning. A fluorescent 28-kDa polypeptide was observed for cells previously exposed to 17OD but not for cells treated with either allylthiourea or acetylene prior to exposure to 17OD or for cells not previously exposed to 17OD. The fluorescent polypeptide was membrane associated and aggregated when heated with β-mercaptoethanol and SDS. The fluorescent polypeptide was also detected in cells pretreated with other diynes, but not in cells pretreated with structural homologs containing a single ethynyl functional group. The membrane fraction from 17OD-treated cells was conjugated with biotin-azide and solubilized in SDS. Streptavidin affinity-purified polypeptides were on-bead trypsin-digested, and amino acid sequences of the peptide fragments were determined by liquid chromatography-mass spectrometry (LC-MS) analysis. Peptide fragments from AmoA were the predominant peptides detected in 17OD-treated samples. In-gel digestion and matrix-assisted laser desorption ionization–tandem time of flight (MALDI-TOF/TOF) analyses also confirmed that the fluorescent 28-kDa polypeptide was AmoA. PMID:26826234

Pediatric PRK (PhotoRefractive Keratectomy) with Mitomycin C (MCC) for Persistent Anisometropic Amblyopia. A Case Report.

PubMed

Crawford, Courtney M; Frazier, Travis C; Torres, Mark F; Arnold, Robert W; Mazzoli, Robert A; Raymond, William R

2012-01-01

To evaluate the safety and efficacy of photorefractive keratectomy (PRK) with Mitomycin C (MMC) for the treatment of severe pediatric anisometropia and amblyopia resistant to more conservative treatment modalities. A 3 year-old-child, who at 18 months old underwent unilateral diode laser treatment for threshold ROP, developed 11 diopters of anisometropic myopia and secondary dense amblyopia of the Right Eye. Only after all conservative treatment options failed was he treated with PRK and MMC. Principal outcome measures included cycloplegic refraction, the amount of refractive correction, degree of corneal haze and change in visual acuity. On presentation: BCVA: 20/CF OD; 20/30 OS. CRNS: -11.50 diopters sphere OD; -0.50 diopters sphere OS. Unilateral PRK followed by application of MMC (0.2 mg/ml) for 1 min was performed under general anesthesia. Three-month postoperative findings include: VA: 20/30 OD; 20/25 OS. CRNS: +0.25 diopters sphere OD. At one year, the BCVA remained equal at the 20/30 level despite mild myopic regression OD. CRNS OD at one year was -1.25 +050 x 116. No corneal haze was appreciated. In this child, treatment with PRK and MMC safely reduced the anisometropia thus facilitating his visual rehabilitation. While encouraging, further study is required to verify the longer term results of this single case. To evaluate the safety and efficacy of photorefractive keratectomy (PRK) with Mitomycin C (MMC) for the treatment of severe pediatric anisometropia and amblyopia resistant to more conservative treatment modalities. A 3 year-old-child, who at 18 months old underwent unilateral diode laser treatment for threshold ROP, developed 11 diopters of anisometropic myopia and secondary dense amblyopia of the Right Eye. Only after all conservative treatment options failed was he treated with PRK and MMC. Principal outcome measures included cycloplegic refraction, the amount of refractive correction, degree of corneal haze and change in visual acuity. On presentation: BCVA: 20/CF OD; 20/30 OS. CRNS: -11.50 diopters sphere OD; -0.50 diopters sphere OS. Unilateral PRK followed by application of MMC (0.2 mg/ml) for 1 min was performed under general anesthesia. Three-month postoperative findings include: VA: 20/30 OD; 20/25 OS. CRNS: +0.25 diopters sphere OD. At one year, the BCVA remained equal at the 20/30 level despite mild myopic regression OD. CRNS OD at one year was -1.25 +050 x 116. No corneal haze was appreciated. In this child, treatment with PRK and MMC safely reduced the anisometropia thus facilitating his visual rehabilitation. While encouraging, further study is required to verify the longer term results of this single case.

Latent Profiles of Externalizing Psychopathology and Their Relation to Children's Aggression and Social Behavior.

PubMed

Andrade, Brendan F; Wade, Mark

2016-01-01

This study identified profiles of clinic-referred children with disruptive behavior and determined the association between identified profiles and children's aggression, peer problems, and prosocial skills. Parents and teachers of 208 children (163 boys) aged 6 to 12 years (Mage = 8.80, SD = 1.75) completed measures to assess children's callous-unemotional (CU) traits, inattentive-impulsive-overactive (IO) and oppositional-defiant (OD) behavior, aggression, and social behaviors. Latent class analysis was used to identify the profiles, and the pseudoclass draw method to test the equality of means for each of the aggression and social behavioral outcomes across the latent classes. Five profiles were identified: (1) Low (35.6% of children), with relatively low levels of CU traits and IO and OD behavior; (2) Low-Moderate (30.8%), with low-moderate levels of CU traits, low IO and moderate OD behavior; (3) Moderate (21.6%), with moderate levels of CU traits and IO and moderate-high OD behavior; (4) Moderate-High (7.2%), with moderate-high levels of CU traits, high IO and moderate-high OD behavior; and (5) High (4.8%), with high levels of CU traits, IO and OD behavior. Children categorized into profiles showed important differences in level of aggression and social behavior. The overlap between CU traits, IO, and OD behavior add to understanding of child psychopathology that influences behavior and clinical outcomes.

The comparison of microstructures and mechanical properties between 14Cr-Al and 14Cr-Ti ferritic ODS alloys

DOE PAGES

Zhang, Guangming; Zhou, Zhangjian; Mo, Kun; ...

2016-03-03

In this study, two kinds of 14Cr ODS alloys (14Cr-Al and 14Cr-Ti) were investigated to reveal the different effects between Al and Ti on the microstructures and mechanical properties of 14Cr ferritic ODS alloys. The microstructure information such as grains, minor phases of these two alloys has been investigated by high-energy X-ray diffraction and transmission electron microscopy (TEM). The in situ synchrotron X-ray diffraction tensile test was applied to investigate the mechanical properties of these two alloys. The lattice strains of different phases through the entire tensile deformation process in these two alloys were analyzed to calculate their elastic stresses.more » From the comparison of elastic stress, the strengthening capability of Y 2Ti 2O 7 is better than TiN in 14Cr-Ti, and the strengthening capability of YAH is much better than YAM and AlN in 14Cr-Al ODS. The dislocation densities of 14Cr-Ti and 14Cr-Al ODS alloys during tensile deformation were also examined by modified Williamson-Hall analyses of peak broadening, respectively. In conclusion, the different increasing speed of dislocation density with plastic deformation reveals the better strengthening effect of Y-Ti-O particles in 14Cr-Ti ODS than that of Y-Al-O particles in 14Cr-Al ODS alloy.« less

Effect of microwave drying and oven drying on the water activity, color, phenolic compounds content and antioxidant activity of coconut husk (Cocos nucifera L.).

PubMed

Valadez-Carmona, Lourdes; Cortez-García, Rosa María; Plazola-Jacinto, Carla Patricia; Necoechea-Mondragón, Hugo; Ortiz-Moreno, Alicia

2016-09-01

The coconut ( Cocos nucifera L.) husk is basically composed by fiber and pith material and remained under-utilized. This is an important source of phenolic compounds that could be used as functional ingredients. The aim of this study was to determine the effect of: oven-drying (OD) and microwave drying (MD), on the water activity, color, phenolic compound content and antioxidant activity of coconut husk. The OD was performed at 60 °C for 12 h and MD was performed at 900 W for 10 min. The total phenolic content (TPC) in fresh coconut husk was 64.2 mg GAE/g dry wt and significant higher than observed after OD and MD of 35.8 and 45.5 mg GAE/g dry wt, respectively. Ten phenols were identified in fresh and dehydrated coconut husks. The husk MD showed an increase in the content of gallic, 4-hydroxybenzoic, ferulic and syringic acids and epicatechin compared with the fresh; while coconut husk OD and MD, showed a decrease in the content of vanillic acid, vanillin, catequin and kaempferol. The antioxidant activity decreased after both OD and MD. However, MD resulted in a better antioxidant activity in husk than OD. MD of husk resulted into better retention of preserved color, TPC and TFC than OD.

Survey Feedback as an Organization Development Strategy in a Public School District.

ERIC Educational Resources Information Center

Rosenbach, William E.; And Others

1983-01-01

Survey feedback can be applied as an organization development (OD) technique in public school systems. The technique, if suited to goals of an OD effort, can result in multiple positive outcomes. In addition to improvements characteristic of OD, the results of survey feedback can be utilized in making strategic decisions. (Author/MH)

European Society for Swallowing Disorders - European Union Geriatric Medicine Society white paper: oropharyngeal dysphagia as a geriatric syndrome.

PubMed

Baijens, Laura Wj; Clavé, Pere; Cras, Patrick; Ekberg, Olle; Forster, Alexandre; Kolb, Gerald F; Leners, Jean-Claude; Masiero, Stefano; Mateos-Nozal, Jesús; Ortega, Omar; Smithard, David G; Speyer, Renée; Walshe, Margaret

2016-01-01

This position document has been developed by the Dysphagia Working Group, a committee of members from the European Society for Swallowing Disorders and the European Union Geriatric Medicine Society, and invited experts. It consists of 12 sections that cover all aspects of clinical management of oropharyngeal dysphagia (OD) related to geriatric medicine and discusses prevalence, quality of life, and legal and ethical issues, as well as health economics and social burden. OD constitutes impaired or uncomfortable transit of food or liquids from the oral cavity to the esophagus, and it is included in the World Health Organization's classification of diseases. It can cause severe complications such as malnutrition, dehydration, respiratory infections, aspiration pneumonia, and increased readmissions, institutionalization, and morbimortality. OD is a prevalent and serious problem among all phenotypes of older patients as oropharyngeal swallow response is impaired in older people and can cause aspiration. Despite its prevalence and severity, OD is still underdiagnosed and untreated in many medical centers. There are several validated clinical and instrumental methods (videofluoroscopy and fiberoptic endoscopic evaluation of swallowing) to diagnose OD, and treatment is mainly based on compensatory measures, although new treatments to stimulate the oropharyngeal swallow response are under research. OD matches the definition of a geriatric syndrome as it is highly prevalent among older people, is caused by multiple factors, is associated with several comorbidities and poor prognosis, and needs a multidimensional approach to be treated. OD should be given more importance and attention and thus be included in all standard screening protocols, treated, and regularly monitored to prevent its main complications. More research is needed to develop and standardize new treatments and management protocols for older patients with OD, which is a challenging mission for our societies.

C-C1-04: How to Win Friends and Influence People with the SAS Output Delivery System

PubMed Central

Tolbert, William

2010-01-01

Background and Aims: Long-time SAS users remember the days when SAS output was embarrassingly ugly. Version 7 saw the introduction of the Output Delivery System (ODS). ODS has matured into a very capable subsystem that gives users powerful reporting options. This presentation will highlight useful features and outline a macro-based system for handling multiple ODS destinations simultaneously. Nowadays there is no excuse for ugly SAS output! When building reports, SAS users should think about the needs of those using the reports. Some people just want to review frequency tables, and are happy to do so on a monitor. Others want to be able to print data for review in a meeting. And, there are always those that want to work with the data in a spreadsheet. Consider the ideal formats for each of the users outlined above. For the casual data browser, HTML output is ideal. For printing, PDF is preferred. And for the additional analysis, Excel is a popular option. With ODS, we can meet all of these needs. Methods: Because ODS permits opening multiple output destinations simultaneously, a single procedure can be used to generate data in HTML, PDF, and Excel at once. The presentation will demonstrate the following: o- basic ODS syntax for HTML, PDF, and Excel output o- custom HTML table of contents o- using the ExcelXP tagset for multi-tab spreadsheets o- a custom macro for managing multiple ODS destinations simultaneously o- simple PROC Template code for easy customization o- techniques for consistent output from multiple platforms. Results: The techniques outlined here have been well-received in a variety of business reporting environments. Conclusions: The SAS ODS provides a wide array of reporting options. Don’t limit yourself to just one type of output.

European Society for Swallowing Disorders – European Union Geriatric Medicine Society white paper: oropharyngeal dysphagia as a geriatric syndrome

PubMed Central

Baijens, Laura WJ; Clavé, Pere; Cras, Patrick; Ekberg, Olle; Forster, Alexandre; Kolb, Gerald F; Leners, Jean-Claude; Masiero, Stefano; Mateos-Nozal, Jesús; Ortega, Omar; Smithard, David G; Speyer, Renée; Walshe, Margaret

2016-01-01

This position document has been developed by the Dysphagia Working Group, a committee of members from the European Society for Swallowing Disorders and the European Union Geriatric Medicine Society, and invited experts. It consists of 12 sections that cover all aspects of clinical management of oropharyngeal dysphagia (OD) related to geriatric medicine and discusses prevalence, quality of life, and legal and ethical issues, as well as health economics and social burden. OD constitutes impaired or uncomfortable transit of food or liquids from the oral cavity to the esophagus, and it is included in the World Health Organization’s classification of diseases. It can cause severe complications such as malnutrition, dehydration, respiratory infections, aspiration pneumonia, and increased readmissions, institutionalization, and morbimortality. OD is a prevalent and serious problem among all phenotypes of older patients as oropharyngeal swallow response is impaired in older people and can cause aspiration. Despite its prevalence and severity, OD is still underdiagnosed and untreated in many medical centers. There are several validated clinical and instrumental methods (videofluoroscopy and fiberoptic endoscopic evaluation of swallowing) to diagnose OD, and treatment is mainly based on compensatory measures, although new treatments to stimulate the oropharyngeal swallow response are under research. OD matches the definition of a geriatric syndrome as it is highly prevalent among older people, is caused by multiple factors, is associated with several comorbidities and poor prognosis, and needs a multidimensional approach to be treated. OD should be given more importance and attention and thus be included in all standard screening protocols, treated, and regularly monitored to prevent its main complications. More research is needed to develop and standardize new treatments and management protocols for older patients with OD, which is a challenging mission for our societies. PMID:27785002

Improved cortisol exposure-time profile and outcome in patients with adrenal insufficiency: a prospective randomized trial of a novel hydrocortisone dual-release formulation.

PubMed

Johannsson, G; Nilsson, A G; Bergthorsdottir, R; Burman, P; Dahlqvist, P; Ekman, B; Engström, B E; Olsson, T; Ragnarsson, O; Ryberg, M; Wahlberg, J; Biller, B M K; Monson, J P; Stewart, P M; Lennernäs, H; Skrtic, S

2012-02-01

Patients with treated adrenal insufficiency (AI) have increased morbidity and mortality rate. Our goal was to improve outcome by developing a once-daily (OD) oral hydrocortisone dual-release tablet with a more physiological exposure-time cortisol profile. The aim was to compare pharmacokinetics and metabolic outcome between OD and the same daily dose of thrice-daily (TID) dose of conventional hydrocortisone tablets. We conducted an open, randomized, two-period, 12-wk crossover multicenter trial with a 24-wk extension at five university hospital centers. The trial enrolled 64 adults with primary AI; 11 had concomitant diabetes mellitus (DM). The same daily dose of hydrocortisone was administered as OD dual-release or TID. We evaluated cortisol pharmacokinetics. Compared with conventional TID, OD provided a sustained serum cortisol profile 0-4 h after the morning intake and reduced the late afternoon and the 24-h cortisol exposure. The mean weight (difference = -0.7 kg, P = 0.005), systolic blood pressure (difference = -5.5 mm Hg, P = 0.0001) and diastolic blood pressure (difference: -2.3 mm Hg; P = 0.03), and glycated hemoglobin (absolute difference = -0.1%, P = 0.0006) were all reduced after OD compared with TID at 12 wk. Compared with TID, a reduction in glycated hemoglobin by 0.6% was observed in patients with concomitant DM during OD (P = 0.004). The OD dual-release tablet provided a more circadian-based serum cortisol profile. Reduced body weight, reduced blood pressure, and improved glucose metabolism were observed during OD treatment. In particular, glucose metabolism improved in patients with concomitant DM.

A pilot study on disturbed gastric myoelectric activity in obstructed defecation syndrome.

PubMed

Farid, Mohamed; Emile, Sameh Hany; Haleem, Magdy; El-Hak, Nabil Gad

2018-07-01

Electrogastrography (EGG) is a noninvasive technique for recording gastric myoelectric activity. The aim of this study was to measure and record gastric myoelectric activity in patients with obstructed defecation syndrome (ODS) and to compare their results with those of normal individuals. Forty-two patients (22 male) with ODS and a mean age of 41.02 y were enrolled in this prospective study after thorough clinical and physiologic assessment. Eleven normal subjects (six female) with a mean age of 39.2 ± 8.4 y were assigned to the control group. Both patients and controls were subjected to surface EGG in fasting and postprandial states. Data were recorded and analyzed via a computer system to reveal the EGG pattern in both groups. Abnormalities in the EGG were found in 24 (57.1%) of the 42 patients with ODS. EGG in ODS patients showed alterations in the fasting state in the form of a significant decrease of the normal gastric slow wave (P = 0.03) and a nonsignificant increase in gastric dysrhythmias. The EGG alterations of ODS patients were significantly improved in the postprandial state as the normal gastric slow waves significantly (P = 0.006) increased and the gastric bradycardia declined significantly (P = 0.02). No significant differences were observed in the power distribution between the ODS patients and the healthy controls. Patients with ODS showed an altered EGG pattern compared with that of healthy control subjects. The alterations in ODS patients were more clearly observed during the fasting state and improved significantly after eating. Copyright © 2018 Elsevier Inc. All rights reserved.

HPLC separation of triacylglycerol positional isomers on a polymeric ODS column.

PubMed

Kuroda, Ikuma; Nagai, Toshiharu; Mizobe, Hoyo; Yoshimura, Nobuhito; Gotoh, Naohiro; Wada, Shun

2008-07-01

A polymeric ODS column was applied to the resolution of triacylglycerol positional isomers (TAG-PI), i.e. 1,3-dioleoyl-2-palmitoyl-glycerol (OPO) and 1,2-dioleoyl-3-palmitoyl-rac-glycerol (OOP), with a recycle HPLC system. To investigate the ODS column species and the column temperatures for the resolution of a TAG-PI pair, a mixture of OPO and OOP was subjected to an HPLC system equipped with a non-endcapped polymeric, endcapped monomeric, endcapped intermediate, or non-endcapped monomeric ODS column at three different column temperatures (40, 25, or 10 degrees C). Only the non-endcapped polymeric ODS column achieved the separation of OPO and OOP, and the lowest column temperature (10 degrees C) showed the best resolution for them. The other pair of TAG-PI, a mixture of 1,3-dipalmitoyl-2-oleoyl-glycerol (POP) and 1,2-dipalmitoyl-3-oleoyl-rac-glycerol (PPO) was also subjected to the system equipped with a non-endcapped polymeric or monomeric ODS column at five different column temperatures (40, 32, 25, 17, and 10 degrees C). Thus, POP and PPO were also separated on only the non-endcapped polymeric ODS column at 25 degrees C. However, no clear peak appeared at 10 degrees C. These results would indicate that the polymeric ODS stationary phase has an ability to recognize the structural differences between TAG-PI pairs. Also, the column temperature is a very important factor for separating the TAG-PI pair, and the optimal temperature would relate to the solubility of TAG-PI in the mobile phase. Furthermore, the recycle HPLC system provided measurements for the separation and analysis of TAG-PI pairs.

Sol-gel open tubular ODS columns with reversed electroosmotic flow for capillary electrochromatography.

PubMed

Hayes, J D; Malik, A

2001-03-01

Sol-gel chemistry was successfully used for the fabrication of open tubular columns with surface-bonded octadecylsilane (ODS) stationary-phase coating for capillary electrochromatography (OT-CEC). Following column preparations, a series of experiments were performed to investigate the performance of the sol-gel coated ODS columns in OT-CEC. The incorporation of N-octadecyldimethyl[3-(trimethoxysilyl)propyl]ammonium chloride as one of the sol-gel precursors played an important role in the electrochromatographic performance of the prepared columns. This chemical reagent possesses a chromatographically favorable, bonded ODS moiety, in conjunction with three methoxy groups allowing for sol-gel reactivity. In addition, a positively charged nitrogen atom is present in the molecular structure of this reagent and provides a positively charged capillary surface responsible for the reversed electroosmotic flow (EOF) in the columns during CEC operation. Comparative studies involving the EOF within such sol-gel ODS coated and uncoated capillaries were performed using acetonitrile and methanol as the organic modifiers in the mobile phase. The use of a deactivating reagent, phenyldimethylsilane, in the sol-gel solution was evaluated. Efficiency values of over 400,000 theoretical plates per meter were achieved in CEC on a 64 cm x 25 microm i.d. sol-gel ODS open tubular column. Test mixtures of polycyclic aromatic hydrocarbons, benzene derivatives, and aromatic aldehydes and ketones were used to evaluate the CEC performances of both nondeactivated and deactivated open tubular sol-gel columns. The effects of mobile-phase organic modifier contents and pH on EOF in such columns were evaluated. The prepared sol-gel ODS columns are characterized by switchable electroosmotic flow. A pH value of approximately 8.5 was found correspond to the isoelectric point for the prepared sol-gel ODS coatings.

Distinction of synthetic dl-α-tocopherol from natural vitamin E (d-α-tocopherol) by reversed-phase liquid chromatography. Enhanced selectivity of a polymeric C18 stationary phase at low temperature and/or at high pressure.

PubMed

Yui, Yuko; Miyazaki, Shota; Ma, Yan; Ohira, Masayoshi; Fiehn, Oliver; Ikegami, Tohru; McCalley, David V; Tanaka, Nobuo

2016-06-10

Separation of diastereomers of dl-α-tocopherol was studied by reversed-phase liquid chromatography using three types of stationary phases, polymeric ODS, polymeric C30, and monomeric ODS. Polymeric ODS stationary phase (Inertsil ODS-P, 3mmID, 20cm) was effective for the separation of the isomers created by the presence of three chiral centers on the alkyl chain of synthetic dl-α-tocopherol. Considerable improvement of the separation of isomers was observed on ODS-P phase at high pressure and at low temperature. Complete separation of four pairs of diastereomers was achieved at 12.0°C, 536bar, while three peaks were observed when the separation was carried out either at 12.0°C at low pressure or at 20°C at 488bar. Higher temperature (30.0°C) with the ODS-P phase resulted in only partial separation of the diastereomers even at high pressure. Only slight resolution was observed for the mixture of diastereomers with the C30 stationary phase (Inertsil C30) at 12.0°C and 441bar, although the stationary phase afforded greater resolution for β- and γ-tocopherol than ODS-P. A monomeric C18 stationary phase did not show any separation at 12.0°C and 463bar. The results suggest that the binding site of the polymeric ODS-P phase is selective for flexible alkyl chains that provided the longest retention for the natural form, (R,R,R) form, and the enantiomer, (S,S,S) form, of dl-α-tocopherol. Copyright © 2016. Published by Elsevier B.V.

Evaluation and reporting of enzyme immunoassay determinations of antibody to herpes simplex virus in sera and cerebrospinal fluid.

PubMed Central

Cremer, N E; Cossen, C K; Hanson, C V; Shell, G R

1982-01-01

Several methods for evaluating and reporting enzyme immunoassay (EIA) determinations of antibody to herpes simplex virus derived from one dilution of single serum samples were studied. An EIA ratio method for serological evidence of current infection from paired serum samples was also evaluated. Optical density (OD) of the reaction at a 1:100 serum dilution and estimated titers obtained by reference of the OD of the serum dilution to a standard curve were compared to the corresponding plotted EIA titer obtained by titration to endpoint. Neither the OD per se nor the estimated titer was completely predictive of the plotted titer (correlation coefficient [r] of 0.824 and 0.817, respectively), and they provided only a semiquantitative measurement of antibody concentration. For an antibody status report, however, OD would be sufficient if related to the cutoff value as an EIA index (OD of sample divided by cutoff OD for positive specimens). The OD of the EIA reaction at a single dilution (1:5) of cerebrospinal fluid, on the other hand, correlated quite well with the titer obtained by titration (r = 0.950). For serological diagnosis of current infection, the OD ratio of convalescence-phase/acute-phase sera was determined at several dilutions. A ratio of greater than or equal to 1.54 was calculated as a reliable index for a significant rise in antibody concentration and compatible with current infection. By determining the convalescent-phase/acute-phase serum ratio at two dilutions, 1:100 and 1:1,000, the EIA ratio method appeared to be a sensitive as or more sensitive than, complement fixation in diagnosing current infection. PMID:6284791

The role of high airway pressure and dynamic strain on ventilator-induced lung injury in a heterogeneous acute lung injury model.

PubMed

Jain, Sumeet V; Kollisch-Singule, Michaela; Satalin, Joshua; Searles, Quinn; Dombert, Luke; Abdel-Razek, Osama; Yepuri, Natesh; Leonard, Antony; Gruessner, Angelika; Andrews, Penny; Fazal, Fabeha; Meng, Qinghe; Wang, Guirong; Gatto, Louis A; Habashi, Nader M; Nieman, Gary F

2017-12-01

Acute respiratory distress syndrome causes a heterogeneous lung injury with normal and acutely injured lung tissue in the same lung. Improperly adjusted mechanical ventilation can exacerbate ARDS causing a secondary ventilator-induced lung injury (VILI). We hypothesized that a peak airway pressure of 40 cmH 2 O (static strain) alone would not cause additional injury in either the normal or acutely injured lung tissue unless combined with high tidal volume (dynamic strain). Pigs were anesthetized, and heterogeneous acute lung injury (ALI) was created by Tween instillation via a bronchoscope to both diaphragmatic lung lobes. Tissue in all other lobes was normal. Airway pressure release ventilation was used to precisely regulate time and pressure at both inspiration and expiration. Animals were separated into two groups: (1) over-distension + high dynamic strain (OD + H DS , n = 6) and (2) over-distension + low dynamic strain (OD + L DS , n = 6). OD was caused by setting the inspiratory pressure at 40 cmH 2 O and dynamic strain was modified by changing the expiratory duration, which varied the tidal volume. Animals were ventilated for 6 h recording hemodynamics, lung function, and inflammatory mediators followed by an extensive necropsy. In normal tissue (N T ), OD + L DS caused minimal histologic damage and a significant reduction in BALF total protein (p < 0.05) and MMP-9 activity (p < 0.05), as compared with OD + H DS . In acutely injured tissue (ALI T ), OD + L DS resulted in reduced histologic injury and pulmonary edema (p < 0.05), as compared with OD + H DS . Both N T and ALI T are resistant to VILI caused by OD alone, but when combined with a H DS , significant tissue injury develops.

Meteoroid/orbital debris impact damage predictions for the Russian space station MIR

NASA Technical Reports Server (NTRS)

Christiansen, E. L.; Hyde, J. L.; Lear, D.

1997-01-01

Components of the Mir space station have been exposed to the meteoroid/orbital debris (M/OD) environment for up to 11 years. During this period, no M/OD impact perforation of the pressure shell of the manned modules were reported. The NASA standard M/OD analysis code BUMPER was used to predict the probability of M/OD impact damage to various components of Mir. The analysis indicates a 1 in 2.2 chance that a M/OD impact would have caused a penetration resulting in a pressure leak of the Mir modules since its launch up to the February 1997. For the next five years, the estimated odds become 1 in 3. On an annual basis, penetration risks are 60 percent higher, on the average, in the next five years due to the larger size of Mir and the growth in the orbital debris population.

Development of Advanced Ods Ferritic Steels for Fast Reactor Fuel Cladding

NASA Astrophysics Data System (ADS)

Ukai, S.; Oono, N.; Ohtsuka, S.; Kaito, T.

Recent progress of the 9CrODS steel development is presented focusing on their microstructure control to improve sufficient high-temperature strength as well as cladding manufacturing capability. The martensitic 9CrODS steel is primarily candidate cladding materials for the Generation IV fast reactor fuel. They are the attractive composite-like materials consisting of the hard residual ferrite and soft tempered martensite, which are able to be easily controlled by α-γ phase transformation. The residual ferrite containing extremely nanosized oxide particles leads to significantly improved creep rupture strength in 9CrODS cladding. The creep strength stability at extended time of 60,000 h at 700 ºC is ascribed to the stable nanosized oxide particles. It was also reviewed that 9CrODS steel has well irradiation stability and fuel pin irradiation test was conducted up to 12 at% burnup and 51 dpa at the cladding temperature of 700ºC.

A flash photolysis-resonance fluorescence study of the formation of O(D-1) in the photolysis of water and reaction of O(D-1) with H2, Ar and He

NASA Technical Reports Server (NTRS)

Stief, L. J.; Payne, W. A.; Klemm, R. B.

1974-01-01

The relative importance of two primary processes in the photolyis of water: (1) H2O + h (nu) yields H + OH, and (2) H2O + h (nu) yields H2 + OD-1 were determined in a direct manner by time resolved detection (via resonance fluorescence) of H and O formed in processes 1 and 2 respectively. The initially formed OD-1 was deactivated to ground state OP-3 prior to detection via resonance fluorescence. The relative quantum yields for processes 1 and 2 are 0.89 and 0.11 for the wavelength interval 105 to 145nm and = to or greater than 0.99, and = to or less than 0.01 for the wavelength interval 145 to 185nm. Rate constants at 300 K for the reactions OD-1 + H2, + Ar, and + He are presented.

Driving technology for improving motion quality of active-matrix organic light-emitting diode display

NASA Astrophysics Data System (ADS)

Kim, Jongbin; Kim, Minkoo; Kim, Jong-Man; Kim, Seung-Ryeol; Lee, Seung-Woo

2014-09-01

This paper reports transient response characteristics of active-matrix organic light emitting diode (AMOLED) displays for mobile applications. This work reports that the rising responses look like saw-tooth waveform and are not always faster than those of liquid crystal displays. Thus, a driving technology is proposed to improve the rising transient responses of AMOLED based on the overdrive (OD) technology. We modified the OD technology by combining it with a dithering method because the conventional OD method cannot successfully enhance all the rising responses. Our method can improve all the transitions of AMOLED without modifying the conventional gamma architecture of drivers. A new artifact is found when OD is applied to certain transitions. We propose an optimum OD selection method to mitigate the artifact. The implementation results show the proposed technology can successfully improve motion quality of scrolling texts as well as moving pictures in AMOLED displays.

Orbital Debris Modeling

NASA Technical Reports Server (NTRS)

Liou, J. C.

2012-01-01

Presentation outlne: (1) The NASA Orbital Debris (OD) Engineering Model -- A mathematical model capable of predicting OD impact risks for the ISS and other critical space assets (2) The NASA OD Evolutionary Model -- A physical model capable of predicting future debris environment based on user-specified scenarios (3) The NASA Standard Satellite Breakup Model -- A model describing the outcome of a satellite breakup (explosion or collision)

Measuring of Mycobacterium tuberculosis growth. A correlation of the optical measurements with colony forming units

PubMed Central

Peñuelas-Urquides, Katia; Villarreal-Treviño, Licet; Silva-Ramírez, Beatriz; Rivadeneyra-Espinoza, Liliana; Said-Fernández, Salvador; de León, Mario Bermúdez

2013-01-01

The quantification of colony forming units (cfu), turbidity, and optical density at 600 nm (OD600) measurements were used to evaluate Mycobacterium tuberculosis growth. Turbidity and OD600 measurements displayed similar growth curves, while cfu quantification showed a continuous growth curve. We determined the cfu equivalents to McFarland and OD600 units. PMID:24159318