ASSESSMENT OF THE POTENTIAL FOR TRANSPORT OF DIOXINS AND CODISPOSED MATERIALS TO GROUNDWATER

EPA Science Inventory

Dioxins are very toxic contaminants and warrant study under a variety of experimental conditions. Studies were performed to evaluate the mobility of several of the dioxins in both soil columns as well as in batch experiments. The studies showed that the amount of chlorination did...

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

Exposure assessment of dioxins and dioxin-like PCBs in pasteurised bovine milk using probabilistic modelling.

PubMed

Adekunte, Adefunke O; Tiwari, Brijesh K; O'Donnell, Colm P

2010-09-01

Quantitative exposure assessment is a useful technique to investigate the risk from contaminants in the food chain. The objective of this study was to develop a probabilistic exposure assessment model for dioxins (PCDD/Fs) and dioxin-like PCBs (DL-PCBs) in pasteurised bovine milk. Mean dioxins and DL-PCBs (non-ortho and mono-ortho PCBs) concentrations (pg WHO-TEQ g(-1)) in bovine milk were estimated as 0.06 ± 0.07 pg WHO-TEQ g(-1) for dioxins and 0.08 ± 0.07 pg WHO-TEQ g(-1) for DL-PCBs using Monte Carlo simulation. The simulated model estimated mean exposure for dioxins was 0.19 ± 0.29 pg WHO-TEQ kg(-1)bw d(-1) and 0.14 ± 0.22 pg WHO-TEQ kg(-1) bw d(-1) and for DL-PCBs was 0.25 ± 0.30 pg WHO-TEQ kg(-1) bw d(-1) and 0.19 ± 0.22 pg WHO-TEQ kg(-1) bw d(-1) for men and women, respectively. This study showed that the mean dioxins and DL-PCBs exposure from consumption of pasteurised bovine milk is below the provisional maximum tolerable monthly intake of 70 pg TEQ kg(-1) bw month(-1) (equivalent of 2.3 pg TEQ kg(-1) bw d(-1)) recommended by the Joint FAO/WHO Expert Committee on Food Additives and Contaminants (JECFA). Results from this study also showed that the estimated dioxins and DL-PCBs concentration in pasteurised bovine milk is comparable to those reported in previous studies. Copyright © 2010 Elsevier Ltd. All rights reserved.

[Preliminary investigation on emission of PCDD/Fs and DL-PCBs through flue gas from coke plants in China].

PubMed

Sun, Peng-Cheng; Li, Xiao-Lu; Cheng, Gang; Lu, Yong; Wu, Chang-Min; Wu, Chang-Min; Luo, Jin-Hong

2014-07-01

According to the Stockholm Convention, polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) are classified into unintentionally produced persistent organic pollutants (UP-POPs), and named dioxins. Coke production as a thermal process contains organic matters, metal and chlorine, is considered to be a potential source of dioxins. Intensive studies on the emission of dioxins from coking industry are still very scarce. In order to estimate the emission properties of dioxins through coke production, isotope dilution HRGC/HRMS technique was used to determine the concentration of dioxins through flue gas during heating of coal. Three results were obtained. First, total toxic equivalents at each stationary emission source were in the range of 3.9-30.0 pg x m(-3) (at WHO-TEQ) for dioxins which was lower than other thermal processes such as municipal solid waste incineration. Second, higher chlorinated PCDD/Fs were the dominant congeners. Third, emissions of dioxins were dependent on coking pattern. Stamping coking and higher coking chamber may lead to lower emission.

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.

Dietary exposure to dioxins and PCBs in a large cohort of pregnant women: results from the Norwegian Mother and Child Cohort Study (MoBa).

PubMed

Caspersen, Ida H; Knutsen, Helle K; Brantsæter, Anne Lise; Haugen, Margaretha; Alexander, Jan; Meltzer, Helle Margrete; Kvalem, Helen E

2013-09-01

Exposure to dioxins and polychlorinated biphenyls (PCBs) during pregnancy and breastfeeding may result in adverse health effects in children. Prenatal exposure is determined by the concentrations of dioxins and PCBs in maternal blood, which reflect the body burden obtained by long term dietary exposure. The aims of this study were (1) to describe dietary exposure and important dietary sources to dioxins and PCBs in a large group of pregnant women and (2) to identify maternal characteristics associated with high dietary exposure to dioxins and PCBs. Dietary exposure to dioxins (sum of toxic equivalents (TEQs) from dioxin-like (dl) compounds) and PCB-153 in 83,524 pregnant women (gestational weeks 17-22) who participated in the Norwegian Mother and Child Cohort Study (MoBa) during the years 2002-2009 was calculated based on a food frequency questionnaire (FFQ) and a database of dioxin and PCB concentrations in Norwegian food. The median (interquartile range, IQR) intake of PCB-153 (marker of ndl-PCBs) was 0.81 (0.77) ng/kg bw/day. For dioxins and dioxin-like PCBs, the median (IQR) intake was 0.56 (0.37) pg TEQ/kg bw/day. Moreover, 2.3% of the participants had intakes exceeding the tolerable weekly intake (TWI) of 14pg TEQ/kg bw/week. Multiple regression analysis showed that dietary exposure was positively associated with maternal age, maternal education, weight gain during pregnancy, being a student, and alcohol consumption during pregnancy and negatively associated with pre-pregnancy BMI and smoking. A high dietary exposure to PCB-153 or dl-compounds (TEQ) was mainly explained by the consumption of seagull eggs and/or pate with fish liver and roe. Women who according to Norwegian recommendations avoid these food items generally do not have dietary exposure above the tolerable intake of dioxins and dl-PCBs. © 2013. Published by Elsevier Ltd. All rights reserved.

An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios (Final Report, 2008)

EPA Science Inventory

EPA announced the availability of the final report, An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios. This report investigates the potential dioxin exposure to artists/hobbyists who use ball clay to make pottery and related products. Derm...

Chlorinated Dioxins and Furans from Kelp and Copper Sulfate ...

EPA Pesticide Factsheets

In 2002, dioxins were discovered in animal feed ingredients during a random sampling by Irish officials and subsequently traced to particular mineral supplements produced at a Minnesota plant in the United States. These products sold under the names of SQM Mineral Products and Carbosan Mineral Products provide trace minerals complexed to polysaccharides for delivery of trace minerals. The products were voluntarily recalled by the company until the source of the dioxins could be identified and the dioxins eliminated from the supplements. Preliminary investigations by the company and federal agencies indicated that the dioxins were apparently produced during the manufacturing process of supplements containing copper, zinc, manganese, magnesium and iron. Additional studies were initiated to identify the specific ingredients required for dioxin formation and to provide further insight into the conditions necessary for their production. Citation: Ferrario, J.; Byrne, C.; Winters, D.; Boone, T.; Vigo, C.; Dupuy, A.; 2003. Chlorinated Dioxins and Furans from Kelp and Copper Sulfate: Initial Investigations of Dioxin Formation in Mineral Feed Supplements. Organohalogen Compounds 63, 183-186.

Dioxin chronology and fluxes in sediments of the Houston Ship Channel, Texas: influences of non-steady-state sediment transport and total organic carbon.

PubMed

Yeager, Kevin M; Santschi, Peter H; Rifai, Hanadi S; Suarez, Monica P; Brinkmeyer, Robin; Hung, Chin-Chang; Schindler, Kimberly J; Andres, Michael J; Weaver, Erin A

2007-08-01

Polychlorinated dibenzo-p-dioxins and dibenzofurans (dioxins) are persistent contaminants that bioaccumulate and pose serious risks to humans. The primary objective of this study was to determine the history and mechanisms of dioxin accumulation in sediments of the Houston Ship Channel (HSC) using analytical data on natural and anthropogenic radionuclides (7Be, 137Cs, and 210Pb) and dioxins. Results showed that present-day sedimentary dioxin accumulation rates are orders of magnitude higher than atmospheric inputs to the HSC. Most stations showed dioxin peaks in the near surface, indicating continuing inputs despite federal regulations. Stations with high dioxin inventories reflect accentuated accumulation in the HSC as one moves west toward Houston, at the confluence of the HSC and the San Jacinto River and upstream in the San Jacinto River. These results indicate that a significant quantity of dioxins continues to be released into the environment here or that sedimentary storage and release of previously supplied dioxins is significant, or both. The results support the interpretation that the HSC is influenced by episodic sediment resuspension, erosion and lateral transport processes driven by tides, wind, shipping, and dredging, which can cause intermittently high accumulations of dioxins, and underscores the need for additional research on the roles of sedimentary processes in organic contaminant bioavailability.

Polychlorinated dioxins, furans, and biphenyls in blood of children and adults living in a dioxin-contaminated area in Tokyo.

PubMed

Tohyama, Chiharu; Uchiyama, Iwao; Hoshi, Shuji; Hijiya, Masaki; Miyata, Hideaki; Nagai, Masaki; Nakai, Satoshi; Yauchi, Mariko; Ohkubo, Satsuki

2011-01-01

The soil of a residential area in Tokyo was found to contain dioxins, namely polychlorinated dioxins, furans, and dioxin-like biphenyls, the levels of which exceeded the environmental guideline [1,000 pg toxic equivalent (TEQ)/g] by up to 6.8 times. To assess the exposure levels of people living in this area and to study the possible relationship of blood dioxin concentrations of children with breast milk and/or formula feeding, a health survey was carried out in 2006, involving a total of 138 people, including 66 children aged 3-15 years, and blood dioxin concentrations and the characteristics and lifestyles of these people were analyzed. Mean ± standard error of the mean (SEM) of blood dioxin concentrations (pg/g-lipid) of group 1 (3-6 years old), group 2 (7-15 years old), and group 3 (≥16 years old) were 13 ± 1.9, 6.6 ± 0.65, and 10 ± 0.54, respectively. The congener/isomer profile of dioxins in blood samples differed markedly from that of the contaminated soil samples. According to the feeding mode of children, blood dioxin concentrations (pg/g-lipid) were 17 ± 2.9 for breast milk only, 7.4 ± 0.82 for both breast milk and formula, and 4.7 ± 1.1 for formula only, with a significant difference from one another. We conclude that people living in the dioxin-contaminated area are less likely to be exposed to excessive amounts of dioxins, and that blood dioxin concentrations of children aged 3-15 years seem to be strongly affected by breast feeding duration.

Dioxin in Midland: A Case Study of Press Coverage of Expert Disagreement.

ERIC Educational Resources Information Center

Palen, John

Drawing from articles appearing in several national publications about the dioxin contamination found in Midland, Michigan, in l983, a case study examined how the publications handled the phenomenon of expert disagreement concerning the nature of dioxin. Specifically, it examined how the publications handled expert disagreement about (1) the way…

Dioxin-metabolizing genes in relation to effects of prenatal dioxin levels and reduced birth size: The Hokkaido study.

PubMed

Kobayashi, Sumitaka; Sata, Fumihiro; Miyashita, Chihiro; Sasaki, Seiko; Ban, Susumu; Araki, Atsuko; Goudarzi, Houman; Kajiwara, Jumboku; Todaka, Takashi; Kishi, Reiko

2017-01-01

We investigated the effects of maternal polymorphisms in 3 genes encoding dioxin-metabolizing enzymes in relation to prenatal dioxin levels on infant birth size in Japan. We examined the relationship between dioxin exposure and birth size in relation to the polymorphisms in the genes encoding aromatic hydrocarbon receptor (AHR [G>A, Arg554Lys]), cytochrome P450 (CYP) 1A1 (T6235C), and glutathione S-transferase mu 1 (GSTM1; Non-null/null) in 421 participants using multiple linear regression models. In mothers carrying the GSTM1 null genotype, a ten-fold increase in total dioxin toxic equivalency was correlated with a decrease in birth weight of -345g (95% confidence interval: -584, -105). We observed adverse effects of maternal GSTM1 null genotype on birth weight in the presence of dioxins exposure during pregnancy. Copyright © 2016 Elsevier Inc. All rights reserved.

Spermatogenesis disruption by dioxins: Epigenetic reprograming and windows of susceptibility.

PubMed

Pilsner, J Richard; Parker, Mikhail; Sergeyev, Oleg; Suvorov, Alexander

2017-04-01

Dioxins are a group of highly persistent chemicals that are generated as by-products of industrial and natural processes. Reduction in sperm counts is among the most sensitive endpoints of dioxin toxicity. The exact mechanism by which dioxins reduce sperm counts is not known. Recent data implicate the role of epididymal factors rather than disruption of spermatogenesis. Studies reviewed here demonstrate that dioxins induce the transfer of environmental conditions to the next generation via male germline following exposures during the window of epigenetic reprogramming of primordial germ cells. Increased incidence of birth defects in offspring of male veterans exposed to dioxin containing, Agent Orange, suggest that dioxins may induce epigenomic changes in male germ cells of adults during spermatogenesis. This is supported by recent animal data that show that environmental conditions can cause epigenetic dysregulation in sperm in the context of specific windows of epigenetic reprogramming during spermatogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

A survey of dioxin-like contaminants in fish from recreational fishing.

PubMed

Heimstad, Eldbjørg Sofie; Grønstøl, Gaute; Hetland, Karl Torstein; Alarcon, Javier Martinez; Rylander, Charlotta; Mariussen, Espen

2015-08-01

The dioxin and dioxin-like compounds are regarded as one of the most toxic group of environmental contaminants. Food for the commercial market is regularly monitored for their dioxin levels and the concentration allowed in food is strictly regulated. Less is known about locally caught fish from recreational fishing, which is often brought home for consumption. This can be fish caught from nearby lakes or streams or fish with marine origin close to industrial areas or harbours that are not regularly monitored for their dioxin levels. In this study, we established collaboration with schools in 13 countries. We received 203 samples of 29 different fish species of which Atlantic cod was the most abundant followed by brown trout and pollock. In general, the majority of samples from the participating countries had low concentrations (between 0.1 and 0.2 pg/g chemical-activated luciferase gene expression toxic equivalency wet weight (CALUX TEQ w.w.)) of dioxins and dioxin-like PCBs. Only 18 samples had concentrations above 1 pg/g CALUX TEQ w.w., and only 2 dab samples had concentration above maximum levels set by the European Commission. The Atlantic cod samples showed a significant reduction in the concentrations of dioxins with increasing latitude indicating less contamination of dioxin and dioxin-like compounds in the north of Norway. The results indicate that a moderate consumption of self-caught fish at presumed non-contaminated sites does not represent a major risk for exposure to dioxins or dioxin-like compounds at concentrations associated with adverse health effects. Recreational fishermen should, however, obtain knowledge about local fish consumption advice.

Physiologically based pharmacokinetic toolkit to evaluate environmental exposures: Applications of the dioxin model to study real life exposures.

PubMed

Emond, Claude; Ruiz, Patricia; Mumtaz, Moiz

2017-01-15

Chlorinated dibenzo-p-dioxins (CDDs) are a series of mono- to octa-chlorinated homologous chemicals commonly referred to as polychlorinated dioxins. One of the most potent, well-known, and persistent member of this family is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). As part of translational research to make computerized models accessible to health risk assessors, we present a Berkeley Madonna recoded version of the human physiologically based pharmacokinetic (PBPK) model used by the U.S. Environmental Protection Agency (EPA) in the recent dioxin assessment. This model incorporates CYP1A2 induction, which is an important metabolic vector that drives dioxin distribution in the human body, and it uses a variable elimination half-life that is body burden dependent. To evaluate the model accuracy, the recoded model predictions were compared with those of the original published model. The simulations performed with the recoded model matched well with those of the original model. The recoded model was then applied to available data sets of real life exposure studies. The recoded model can describe acute and chronic exposures and can be useful for interpreting human biomonitoring data as part of an overall dioxin and/or dioxin-like compounds risk assessment. Copyright © 2016. Published by Elsevier Inc.

Environmental Health Risk Assessment of Dioxin Exposure through Foods in a Dioxin Hot Spot—Bien Hoa City, Vietnam

PubMed Central

Tuyet-Hanh, Tran Thi; Vu-Anh, Le; Ngoc-Bich, Nguyen; Tenkate, Thomas

2010-01-01

This study used the Australian Environmental Health Risk Assessment Framework to assess the human health risk of dioxin exposure through foods for local residents in two wards of Bien Hoa City, Vietnam. These wards are known hot-spots for dioxin and a range of stakeholders from central government to local levels were involved in this process. Publications on dioxin characteristics and toxicity were reviewed and dioxin concentrations in local soil, mud, foods, milk and blood samples were used as data for this risk assessment. A food frequency survey of 400 randomly selected households in these wards was conducted to provide data for exposure assessment. Results showed that local residents who had consumed locally cultivated foods, especially fresh water fish and bottom-feeding fish, free-ranging chicken, duck, and beef were at a very high risk, with their daily dioxin intake far exceeding the tolerable daily intake recommended by the WHO. Based on the results of this assessment, a multifaceted risk management program was developed and has been recognized as the first public health program ever to have been implemented in Vietnam to reduce the risks of dioxin exposure at dioxin hot-spots. PMID:20623031

Epidemiological approaches in the investigation of environmental causes of cancer: the case of dioxins and water disinfection by-products

PubMed Central

2011-01-01

I will refer in this paper to difficulties in research in environmental causes of cancer using as examples research on dioxins and on drinking water disinfection by-products (DBPs) that have created considerable controversy in the scientific and wider community. Dioxins are highly toxic chemicals that are animal carcinogens. For many years, evaluation of the carcinogenicity of dioxins in humans was based on case-control or registry based studies. The development of methods to measure dioxins in blood indicated that these studies suffered from extreme exposure misclassification. The conduct of large cohort studies of workers with widely contrasted exposures together with the use of biomarkers and models for exposure assessment, led to convincing evidence on the carcinogenicity of dioxins in humans. The high toxicity of a few dioxin congeners, the availability of a scheme to characterize the toxicity of a mixture of dioxins and related compounds and the long half-life of these compounds facilitated epidemiological research. Contrary to dioxins, trihalomethanes (THMs) and most of the hundreds of DBPs in drinking water are chemicals of low toxicity. For more than 15 years, the main evidence on the carcinogenicity of DBPs was through ecological or death certificate studies. More recent studies based on individual assessment confirmed increases in bladder cancer risk. However even those studies ignored the toxicological evidence on the importance of routes of exposure to DBPs other than ingestion and, probably, underestimated the risk. Persistence of weak study designs together with delays in advanced exposure assessment models led to delays in confirming early evidence on the carcinogenicity of DBPs. The evaluation of only a few chemicals when exposure is to a complex mixture remains a major problem in exposure assessment for DBPs. The success of epidemiological studies in identifying increased risks lies primarily on the wide contrast of exposure to DBPs in the general population that overcomes the significant exposure misclassification. Exposure assessment has been the Achilles heel for studies on dioxins and DBPs and cancer. The combination of powerful study designs, advanced exposure assessment together with a better understanding of mechanisms of disease and the use of biomarkers of exposure, led to the strengthening of the epidemiological evidence. PMID:21489213

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

Correlation between human maternal-fetal placental transfer and molecular weight of PCB and dioxin congeners/isomers.

PubMed

Mori, Chisato; Nakamura, Noriko; Todaka, Emiko; Fujisaki, Takeyoshi; Matsuno, Yoshiharu; Nakaoka, Hiroko; Hanazato, Masamichi

2014-11-01

Establishing methods for the assessment of fetal exposure to chemicals is important for the prevention or prediction of the child's future disease risk. In the present study, we aimed to determine the influence of molecular weight on the likelihood of chemical transfer from mother to fetus via the placenta. The correlation between molecular weight and placental transfer rates of congeners/isomers of polychlorinated biphenyls (PCBs) and dioxins was examined. Twenty-nine sample sets of maternal blood, umbilical cord, and umbilical cord blood were used to measure PCB concentration, and 41 sample sets were used to analyze dioxins. Placental transfer rates were calculated using the concentrations of PCBs, dioxins, and their congeners/isomers within these sample sets. Transfer rate correlated negatively with molecular weight for PCB congeners, normalized using wet and lipid weights. The transfer rates of PCB or dioxin congeners differed from those of total PCBs or dioxins. The transfer rate for dioxin congeners did not always correlate significantly with molecular weight, perhaps because of the small sample size or other factors. Further improvement of the analytical methods for dioxin congeners is required. The findings of the present study suggested that PCBs, dioxins, or their congeners with lower molecular weights are more likely to be transferred from mother to fetus via the placenta. Consideration of chemical molecular weight and transfer rate could therefore contribute to the assessment of fetal exposure. Copyright © 2014 Elsevier Ltd. All rights reserved.

Environmental toxicology of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans.

PubMed Central

Vanden Heuvel, J P; Lucier, G

1993-01-01

Few environmental compounds have generated as much interest and controversy within the scientific community and in the lay public as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Their ubiquitous presence in the environment and the risk of accidental exposure has raised concern over a possible threat of PCDDs or PCDFs to human health. The most extensively studied and potent isomer is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD or dioxin). Dioxin is a multisite toxicant in laboratory rodents resulting in a number of tissue-, species-, and sex-dependent responses. Much has been learned about the mechanism of dioxin's effects, especially for the induction of cytochrome P-450 enzymes. Binding of PCDDs and PCDFs to a receptor protein, termed the dioxin or Ah receptor, is necessary for most biological and toxic responses. The most common toxic response used for evaluating the human health risk posed by PCDDs and PCDFs is the hepatocarcinogenic response observed primarily in rodents. Despite extensive research efforts, the effects of PCDDs and PCDFs on humans are not well characterized. However, available data indicate there is good agreement between known effects of dioxin in laboratory animals and those described in epidemiological studies for effects in humans. The sequence in events initiated by the Ah receptor interacting with dioxin-responsive genes and ending with altered patterns of differentiation and growth must be sought in order to understand tissue, species, sex, and interindividual variation in biological responses and the health risk posed by PCDDs and PCDFs. PMID:8394802

Elimination Rates of Dioxin Congeners in Former Chlorophenol Workers from Midland, Michigan

PubMed Central

Collins, James J.; Bodner, Kenneth M.; Wilken, Michael; Bodnar, Catherine M.

2012-01-01

Background: Exposure reconstructions and risk assessments for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and other dioxins rely on estimates of elimination rates. Limited data are available on elimination rates for congeners other than TCDD. Objectives: We estimated apparent elimination rates using a simple first-order one-compartment model for selected dioxin congeners based on repeated blood sampling in a previously studied population. Methods: Blood samples collected from 56 former chlorophenol workers in 2004–2005 and again in 2010 were analyzed for dioxin congeners. We calculated the apparent elimination half-life in each individual for each dioxin congener and examined factors potentially influencing elimination rates and the impact of estimated ongoing background exposures on rate estimates. Results: Mean concentrations of all dioxin congeners in the sampled participants declined between sampling times. Median apparent half-lives of elimination based on changes in estimated mass in the body were generally consistent with previous estimates and ranged from 6.8 years (1,2,3,7,8,9-hexachlorodibenzo-p-dioxin) to 11.6 years (pentachlorodibenzo-p-dioxin), with a composite half-life of 9.3 years for TCDD toxic equivalents. None of the factors examined, including age, smoking status, body mass index or change in body mass index, initial measured concentration, or chloracne diagnosis, was consistently associated with the estimated elimination rates in this population. Inclusion of plausible estimates of ongoing background exposures decreased apparent half-lives by approximately 10%. Available concentration-dependent toxicokinetic models for TCDD underpredicted observed elimination rates for concentrations < 100 ppt. Conclusions: The estimated elimination rates from this relatively large serial sampling study can inform occupational and environmental exposure and serum evaluations for dioxin compounds. PMID:23063871

Structural-functional adaptations of porcine CYP1A1 to metabolize polychlorinated dibenzo-p-dioxins.

PubMed

Molcan, Tomasz; Swigonska, Sylwia; Orlowska, Karina; Myszczynski, Kamil; Nynca, Anna; Sadowska, Agnieszka; Ruszkowska, Monika; Jastrzebski, Jan Pawel; Ciereszko, Renata E

2017-02-01

Polychlorinated dibenzo-p-dioxins (PCDDs) are widespread by-products of human industrial activity. They accumulate in tissues of animals and humans, exerting numerous adverse effects on different systems. In living organisms, dioxins are metabolized by enzymes of the cytochrome P450 family, including CYP1A1. Particular dioxin congeners differ in their toxicity level and ability to undergo biodegradation. Since the molecular mechanisms underlying dioxin susceptibility or resistance to biodegradation are unknown, in the present study the molecular interactions between five selected dioxins and porcine CYP1A1 protein were investigated. It was found that the ability of a dioxin to undergo CYP1A1-mediated degradation is associated mainly with the number and position of chlorine atoms in the dioxin molecule. Among all examined congeners, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) demonstrated the highest affinity to CYP1A1 and, at the same time, the greatest distance to the active site of the enzyme. Interestingly, in contrast to other dioxins, the binding of the TCDD molecule to the porcine CYP1A1 active site resulted in a rapid and continuous closure of substrate channels. All the information may help to explain the extended half-life of TCDD in living organisms as well as its high toxicity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prenatal dioxin exposure estimated from dioxins in breast milk and sex hormone levels in umbilical cord blood in Vietnamese newborn infants.

PubMed

Boda, Hitomi; Nghi, Tran Ngoc; Nishijo, Muneko; Thao, Pham Ngoc; Tai, Pham The; Van Luong, Hoang; Anh, Tran Hai; Morikawa, Yuko; Nishino, Yoshikazu; Nishijo, Hisao

2018-02-15

Dioxin concentrations remain elevated in the environment and humans residing near the former US Air Force base in Bien Hoa city, South Vietnam. We recruited 210 mother-infant pairs for whom breast milk dioxin levels were reported in our previous study. Cord blood samples were collected from 162 mother-infant pairs. We selected 16 cord blood samples with a volume over 20mL and fat content of ≥0.03g. Toxic equivalent levels of polychlorinated dibenzodioxins and polychlorinated dibenzofurans (TEQ-PCDD/Fs) and concentrations of 17 congeners, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), in cord blood were measured and compared with levels in breast milk (Study 1). Levels of 2,3,7,8-TCDD and TEQ-PCDD/Fs in cord blood samples were highly and significantly correlated with those in breast milk samples in the same pairs. This suggests dioxins in breast milk reflect prenatal dioxin exposure. Estradiol (E2) and testosterone (TS) were measured in cord blood serum from 162 samples. Associations between dioxins in breast milk and cord blood sex hormones were analyzed by infant sex, after adjusting for confounding factors (Study 2). Increased levels of TEQ-PCDD/Fs in breast milk were associated with decreased cord blood TS in girls. In boys, a significant reduction of cord blood TS was observed in those exposed to 2,3,7,8-TCDD at high levels (≥5.5pg/g lipid). There was no significant association between E2 and dioxins in breast milk in either sex. These results suggest increased prenatal dioxin exposure is associated with decreased cord TS, but in boys, only high level of 2,3,7,8-TCDD influence cord blood TS. Copyright © 2017. Published by Elsevier B.V.

The use of the DR CALUX bioassay and indicator polychlorinated biphenyls for screening of elevated levels of dioxins and dioxin-like polychlorinated biphenyls in eel.

PubMed

Hoogenboom, Ron; Bovee, Toine; Traag, Win; Hoogerbrugge, Ronald; Baumann, Bert; Portier, Liza; van de Weg, Guido; de Vries, Jaap

2006-10-01

The DR CALUX bioassay is a very suitable screening method for dioxins and dioxin-like-PCBs in feed and food. This was, e. g. demonstrated in a survey in the Netherlands to control the dioxin levels in eel. The DR CALUX assay, but also indicator polychlorinated biphenyls (PCB) were evaluated as a screening method. Based on the limit for polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/F) [at that time 8 pg toxic equivalents (TEQ)/g eel], and the relation between PCDD/F and dioxin-like-PCB, a decision limit of 30 pg TEQ/g eel was used for screening of 153 field samples. Suspected samples (21) and part of the higher contaminated negative samples (35) were analyzed by GC/MS for dioxins, non-ortho, mono-ortho and indicator PCB, revealing 13 samples exceeding the action limit of 30 pg TEQ/g eel. Only one sample slightly exceeded the dioxin level of 8 pg TEQ/g eel. The relatively low sensitivity for mono-ortho PCB was overcome by the use of reference samples, as shown by the correlation of 0.93 between GC/MS and CALUX determined total TEQ levels. The present data show that the DR CALUX assay can be used for screening of total TEQ levels in eel. The use for dioxins only requires a safe, and therefore relatively low, decision limit. The indicator PCB also showed a good correlation with total TEQ levels, mainly due to the large contribution of the mono-ortho PCB at higher concentrations. The relation with dioxins was very poor and as such indicator PCB seem less suitable than the DR CALUX assay for screening for dioxins only. The present study clearly shows that part of the wild eel samples contains high total TEQ levels and will exceed the future European Union limit of 12 pg TEQ/g eel for dioxins and dioxin-like PCB. Especially at high TEQ levels, dioxin-like PCB contribute most to the total TEQ. In practice, wild eel presents only a minor part of the eel consumed.

Concentrations of dioxins and dioxin-like PCBs in feed materials in the Netherlands, 2001-11.

PubMed

Adamse, Paulien; Van der Fels-Klerx, H J Ine; Schoss, Stefanie; de Jong, Jacob; Hoogenboom, Ron L A P

2015-01-01

This study aimed to obtain insights into contamination of feed materials used in the Netherlands with dioxins (polychlorinated dibenzo-p-dioxins and dibenzofurans) and dioxin-like polychlorinated biphenyls (PCBs). Monitoring results from the period 2001-11, covering in total 4938 samples, were statistically analysed and evaluated against the statutory limits set at the beginning or during this period. The percentage of samples exceeding maximum levels set within the European Union for either dioxins or the sum of dioxins and dioxin-like PCBs were below 1% for most feed categories, except for fish meal (4.1%), clay minerals (binders and anti-caking agents) (3.4%), and vegetable oils and byproducts (1.7%). For most feed categories, non-compliance with the action threshold (roughly 33% lower than maximum levels) for either dioxins or dioxin-like PCBs was up to three times higher than non-compliance with the respective maximum levels. Exceedance of action thresholds was just above 1% for animal fat, pre-mixtures and feed materials of plant origin excluding vegetable oils. For the categories fish meal, clay minerals, and vegetable oils and byproducts, the action thresholds were exceeded by 5.0%, 9.8% and 3.0% of the samples, respectively. In general, the percentages of samples that exceeded the action thresholds and maximum levels were lower than those reported for the European Union by the European Food Safety Authority (EFSA). In most of the feed materials, there seems to be a decreasing trend in concentrations of dioxins or dioxin-like PCBs over the years. However, a lowering of the limits of quantification during this period and the low concentrations in most samples precludes drawing strong conclusions.

Association between Blood Dioxin Level and Chronic Kidney Disease in an Endemic Area of Exposure

PubMed Central

Huang, Chien-Yuan; Wu, Cheng-Long; Wu, Jin-Shang; Chang, Jung-Wei; Cheng, Ya-Yun; Kuo, Yau-Chang; Yang, Yi-Ching

2016-01-01

Background Dioxin is an industrial pollutant related to various diseases, but epidemiological data on its effects on the kidney are limited. Therefore, we conducted a study to evaluate the association between dioxin exposure and chronic kidney disease (CKD) and identify the related factors. Methods We conducted a community-based cross-sectional study and recruited participants from an area where the residents were exposed to dioxin released from a factory. We defined a “high dioxin level” as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) ≥ 20 pg WHO98-TEQDF/g lipid in the serum and defined CKD as having an estimated glomerular filtration rate (e-GFR) ≤ 60 mL/min/1.73m2 or a diagnosis of CKD by a physician. The renal function was assessed between 2005 and 2010, and we excluded those who had had kidney diseases before the study started. Comparisons between patients of CKD and those who did not have CKD were made to identify the risk factors for CKD. Results Of the 2898 participants, 1427 had high dioxin levels, and 156 had CKD. In the univariate analyses, CKD was associated with high dioxin levels, age, gender, metabolic syndrome, diabetes mellitus, hypertension, and high insulin and uric acid levels. After adjusting for other factors, we found high dioxin levels (adjusted odds ratio [AOR] = 1.76, 95% confidence interval [CI]: 1.04–2.99), female gender (AOR = 1.74, 95%CI: 1.20–2.53), hypertension (AOR = 1.68, 95%CI: 1.17–2.42), high insulin levels (AOR = 2.14, 95% CI: 1.26–3.61), high uric acid levels (AOR = 4.25, 95% CI: 2.92–6.20), and older age (AOR = 4.66, 95% CI: 1.87–11.62 for 40–64 year and AOR = 26.66, 95% CI: 10.51–67.62 for age ≥ 65 year) were independent predictors of CKD. Conclusion A high dioxin level was associated with an increased prevalence of CKD. Therefore, the kidney function of populations with exposure to dioxin should be monitored. PMID:26963719

Association between Blood Dioxin Level and Chronic Kidney Disease in an Endemic Area of Exposure.

PubMed

Huang, Chien-Yuan; Wu, Cheng-Long; Wu, Jin-Shang; Chang, Jung-Wei; Cheng, Ya-Yun; Kuo, Yau-Chang; Yang, Yi-Ching; Lee, Ching-Chang; Guo, How-Ran

2016-01-01

Dioxin is an industrial pollutant related to various diseases, but epidemiological data on its effects on the kidney are limited. Therefore, we conducted a study to evaluate the association between dioxin exposure and chronic kidney disease (CKD) and identify the related factors. We conducted a community-based cross-sectional study and recruited participants from an area where the residents were exposed to dioxin released from a factory. We defined a "high dioxin level" as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) ≥ 20 pg WHO98-TEQDF/g lipid in the serum and defined CKD as having an estimated glomerular filtration rate (e-GFR) ≤ 60 mL/min/1.73m2 or a diagnosis of CKD by a physician. The renal function was assessed between 2005 and 2010, and we excluded those who had had kidney diseases before the study started. Comparisons between patients of CKD and those who did not have CKD were made to identify the risk factors for CKD. Of the 2898 participants, 1427 had high dioxin levels, and 156 had CKD. In the univariate analyses, CKD was associated with high dioxin levels, age, gender, metabolic syndrome, diabetes mellitus, hypertension, and high insulin and uric acid levels. After adjusting for other factors, we found high dioxin levels (adjusted odds ratio [AOR] = 1.76, 95% confidence interval [CI]: 1.04-2.99), female gender (AOR = 1.74, 95%CI: 1.20-2.53), hypertension (AOR = 1.68, 95%CI: 1.17-2.42), high insulin levels (AOR = 2.14, 95% CI: 1.26-3.61), high uric acid levels (AOR = 4.25, 95% CI: 2.92-6.20), and older age (AOR = 4.66, 95% CI: 1.87-11.62 for 40-64 year and AOR = 26.66, 95% CI: 10.51-67.62 for age ≥ 65 year) were independent predictors of CKD. A high dioxin level was associated with an increased prevalence of CKD. Therefore, the kidney function of populations with exposure to dioxin should be monitored.

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.

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.

EMISSIONS OF DIOXINS AND RELATED COMPOUNDS FROM COMBUSTION AND INCINERATION SOURCES

EPA Science Inventory

This report on the emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans was prepared as a contribution to the Pilot Study on International Information Exchange on Dioxins and Related Compounds. he report describes the state of the art with respect to combustion and th...

INNOVATIVE SCREENING TECHNOLOGIES FOR DIOXINS IN SOIL

EPA Science Inventory

Dioxins are recognized as one of the most pervasive and toxic class of chemicals in the environment. They have been the focus of various human exposure studies and have been found at numerous Superfund and other hazardous waste sites. The cost of dioxin analysis represents a s...

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.

EVALUATION OF THE LEVELS OF DIOXIN-LIKE COMPOUNDS IN ANIMAL FEEDS

EPA Science Inventory

The purpose of this study is to measure the levels of dioxin-like compounds in the feeds of terrestrial food animals - cattle, swine, and poultry - and to understand their contribution to the dioxin-like levels found in the animals. It is an ongoing effort involving several phase...

Dioxin emissions from a solid waste incinerator and risk of non-Hodgkin lymphoma.

PubMed

Floret, Nathalie; Mauny, Frédéric; Challier, Bruno; Arveux, Patrick; Cahn, Jean-Yves; Viel, Jean-François

2003-07-01

It is not clear whether low environmental doses of dioxin affect the general population. We previously detected a cluster of patients with non-Hodgkin lymphoma around a French municipal solid waste incinerator with high dioxin emissions. To explore the environmental route suggested by these findings, we carried out a population-based case-control study in the same area. We compared 222 incident cases of non-Hodgkin lymphoma diagnosed between 1980 and 1995 and controls randomly selected from the 1990 population census, using a 10-to-1 match. Dioxin ground-level concentrations were modeled with a second-generation Gaussian-type dispersion model, yielding four dioxin exposure categories. The latter were linked to individual places of residence, using Geographic Information System technology. The risk of developing non-Hodgkin lymphoma was 2.3 times higher (95% confidence interval = 1.4-3.8) among individuals living in the area with the highest dioxin concentration than among those living in the area with the lowest dioxin concentration. No increased risk was found for the intermediate dioxin exposure categories. Adjustment for a wide range of socioeconomic characteristics at the block group level did not alter the results. Although emissions from incinerators are usually not regarded as an important source of exposure to dioxins compared with other background sources, our findings support the hypothesis that environmental dioxins increase the risk of non-Hodgkin lymphoma among the population living in the vicinity of a municipal solid waste incinerator.

Determination of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in human serum using programmable-temperature vaporization gas chromatography with high-resolution mass spectrometry.

PubMed

Zhang, Lei; Zhong, Yuxin; Liu, Xin; Bao, Yan; Zhao, Yunfeng; Wu, Yongning; Cai, Zongwei; Li, Jingguang

2017-09-01

The determination of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in blood from a non-occupational population is essential for the investigation of adverse health effects from these pollutants. In this study, a sensitive method based on programmable-temperature vaporization with large-volume injection coupled with gas chromatography with high-resolution mass spectrometry was developed to determine these pollutants in 1-2 mL of human serum samples. Various key parameters of programmable-temperature vaporization injector, including vent temperature, vent time, vent flow, transfer temperature and transfer time were optimized by factorial design. The accuracy and precision as well as applicability were assessed by determining polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in calibration standard solutions, standard reference materials and real human serum samples from non-occupational population. The method detection limits of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls were 1.5-9.0 and 0.005-0.02 ng/kg wet weight, respectively. By comparing with typically splitless injection, the application of programmable-temperature vaporization injector could effectively lead to higher detectable rate of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in 1-2 mL of human serum samples. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Genetic modification of the association between peripubertal dioxin exposure and pubertal onset in a cohort of Russian boys.

PubMed

Humblet, Olivier; Korrick, Susan A; Williams, Paige L; Sergeyev, Oleg; Emond, Claude; Birnbaum, Linda S; Burns, Jane S; Altshul, Larisa M; Patterson, Donald G; Turner, Wayman E; Lee, Mary M; Revich, Boris; Hauser, Russ

2013-01-01

Exposure to dioxins has been associated with delayed pubertal onset in both epidemiologic and animal studies. Whether genetic polymorphisms may modify this association is currently unknown. Identifying such genes could provide insight into mechanistic pathways. This is one of the first studies to assess genetic susceptibility to dioxins. We evaluated whether common polymorphisms in genes affecting either molecular responses to dioxin exposure or pubertal onset influence the association between peripubertal serum dioxin concentration and male pubertal onset. In this prospective cohort of Russian adolescent boys (n = 392), we assessed gene-environment interactions for 337 tagging single-nucleotide polymorphisms (SNPs) from 46 candidate genes and two intergenic regions. Dioxins were measured in the boys' serum at age 8-9 years. Pubertal onset was based on testicular volume and on genitalia staging. Statistical approaches for controlling for multiple testing were used, both with and without prescreening for marginal genetic associations. After accounting for multiple testing, two tag SNPs in the glucocorticoid receptor (GR/NR3C1) gene and one in the estrogen receptor-α (ESR1) gene were significant (q < 0.2) modifiers of the association between peripubertal serum dioxin concentration and male pubertal onset defined by genitalia staging, although not by testicular volume. The results were sensitive to whether multiple comparison adjustment was applied to all gene-environment tests or only to those with marginal genetic associations. Common genetic polymorphisms in the glucocorticoid receptor and estrogen receptor-α genes may modify the association between peripubertal serum dioxin concentration and pubertal onset. Further studies are warranted to confirm these findings.

Association of dioxins, furans and dioxin-like PCBs in human blood with nephropathy among US teens and young adults.

PubMed

Everett, Charles J; Thompson, Olivia M

2016-06-01

We assessed the association of three chlorinated dibenzo-p-dioxins, a chlorinated dibenzofuran, and four dioxin-like polychlorinated biphenyls (PCBs) in human blood with nephropathy (microalbuminuria or macroalbuminuria) among teens and young adults (12-30 years old) having normal glycohemoglobin (A1c <5.7%). The data were derived from the 1999-2004 National Health and Nutrition Examination Survey (unweighted n=1504, population estimate=38,806,338). In this paper, nephropathy refers to normal A1c with nephropathy. In an all-adult sample (Everett CJ, Thompson OM. Dioxins, furans and dioxin-like PCBs in human blood: causes or consequences of diabetic nephropathy? Environ Res 2014;132:126-31), the cut-offs for these chemicals being considered elevated, were defined as the 75th percentile. Using these same cut-offs again, the proportion of those with one or more of the eight dioxin-like compounds elevated was 9.9%. The four chemicals associated with nephropathy were 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin, PCB 126, PCB 169, and PCB 156. The proportion with one or more of these four dioxin-like chemicals elevated was 3.9% (unweighted n=46) and the odds ratio (OR) for nephropathy was 7.1 [95% confidence interval (CI) 1.8-28.1]. The association was strong among females (OR 17.4, 95% CI 3.4-88.6), but among males there were no cases of nephropathy when one or more of the four dioxin-like chemicals were elevated, and therefore no association. In a separate analysis, elevated toxic equivalency, defined using the eight dioxin-like chemicals (TEQ8), was associated with nephropathy. TEQ8 ≥50.12 fg/g included 2.6% of the sample (unweighted n=28) and had an OR of 5.8 (95% 1.3-25.9) for nephropathy. As found in the analysis of one or more of four dioxin-like chemicals elevated, TEQ8 ≥50.12 fg/g was associated with nephropathy among females (OR 11.9, 95% CI 1.6-87.2), but not males. Trends for least-squares means also differed by gender, but there were no significant differences in mean TEQ8 between normal subjects and those having nephropathy in either males or females. We also evaluated pre-diabetes (A1c 5.7-6.4%) without nephropathy and found no associations when one or more of four dioxin-like compounds were elevated, or when TEQ8 was ≥50.12 fg/g. In this study, associations of dioxin-like chemicals with nephropathy were found among females at an early age. Prospective studies are needed to determine if dioxin-like compounds cause nephropathy, or if these relationships are cases of reverse causation.

In utero exposure to dioxins and dioxin-like compounds and anogenital distance in newborns and infants.

PubMed

Vafeiadi, Marina; Agramunt, Silvia; Papadopoulou, Eleni; Besselink, Harrie; Mathianaki, Kleopatra; Karakosta, Polyxeni; Spanaki, Ariana; Koutis, Antonis; Chatzi, Leda; Vrijheid, Martine; Kogevinas, Manolis

2013-01-01

Anogenital distance in animals is used as a measure of fetal androgen action. Prenatal exposure to dioxins and dioxin-like compounds in rodents causes reproductive changes in male offspring and decreases anogenital distance. We assessed whether in utero exposure to dioxins and dioxin-like compounds adversely influences anogenital distance in newborns and young children (median age, 16 months; range, 1-31 months). We measured anogenital distance among participants of the "Rhea" mother-child cohort study in Crete and the Hospital del Mar (HMAR) cohort in Barcelona. Anogenital distance (AGD; anus to upper penis), anoscrotal distance (ASD; anus to scrotum), and penis width (PW) were measured in 119 newborn and 239 young boys; anoclitoral (ACD; anus to clitoris) and anofourchetal distance (AFD; anus to fourchette) were measured in 118 newborn and 223 young girls. We estimated plasma dioxin-like activity in maternal blood samples collected at delivery with the Dioxin-Responsive Chemically Activated LUciferase eXpression (DR CALUX®) bioassay. Anogenital distances were sexually dimorphic, being longer in males than females. Plasma dioxin-like activity was negatively associated with AGD in male newborns. The estimated change in AGD per 10 pg CALUX®-toxic equivalent/g lipid increase was -0.44 mm (95% CI: -0.80, -0.08) after adjusting for confounders. Negative but smaller and nonsignificant associations were observed for AGD in young boys. No associations were found in girls. Male infants may be susceptible to endocrine-disrupting effects of dioxins. Our findings are consistent with the experimental animal evidence used by the Food and Agriculture Organization/World Health Organization to set recommendations for human dioxin intake.

In Utero Exposure to Dioxins and Dioxin-like Compounds and Anogenital Distance in Newborns and Infants

PubMed Central

Vafeiadi, Marina; Agramunt, Silvia; Papadopoulou, Eleni; Besselink, Harrie; Mathianaki, Kleopatra; Karakosta, Polyxeni; Spanaki, Ariana; Koutis, Antonis; Chatzi, Leda; Vrijheid, Martine

2012-01-01

Background: Anogenital distance in animals is used as a measure of fetal androgen action. Prenatal exposure to dioxins and dioxin-like compounds in rodents causes reproductive changes in male offspring and decreases anogenital distance. Objective: We assessed whether in utero exposure to dioxins and dioxin-like compounds adversely influences anogenital distance in newborns and young children (median age, 16 months; range, 1–31 months). Methods: We measured anogenital distance among participants of the “Rhea” mother–child cohort study in Crete and the Hospital del Mar (HMAR) cohort in Barcelona. Anogenital distance (AGD; anus to upper penis), anoscrotal distance (ASD; anus to scrotum), and penis width (PW) were measured in 119 newborn and 239 young boys; anoclitoral (ACD; anus to clitoris) and anofourchetal distance (AFD; anus to fourchette) were measured in 118 newborn and 223 young girls. We estimated plasma dioxin-like activity in maternal blood samples collected at delivery with the Dioxin-Responsive Chemically Activated LUciferase eXpression (DR CALUX®) bioassay. Results: Anogenital distances were sexually dimorphic, being longer in males than females. Plasma dioxin-like activity was negatively associated with AGD in male newborns. The estimated change in AGD per 10 pg CALUX®–toxic equivalent/g lipid increase was –0.44 mm (95% CI: –0.80, –0.08) after adjusting for confounders. Negative but smaller and nonsignificant associations were observed for AGD in young boys. No associations were found in girls. Conclusions: Male infants may be susceptible to endocrine-disrupting effects of dioxins. Our findings are consistent with the experimental animal evidence used by the Food and Agriculture Organization/World Health Organization to set recommendations for human dioxin intake. PMID:23171674

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

Physiologically based pharmacokinetic toolkit to evaluate environmental exposures: Applications of the dioxin model to study real life exposures

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

Emond, Claude, E-mail: claude.emond@biosmc.com

Chlorinated dibenzo-p-dioxins (CDDs) are a series of mono- to octa-chlorinated homologous chemicals commonly referred to as polychlorinated dioxins. One of the most potent, well-known, and persistent member of this family is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). As part of translational research to make computerized models accessible to health risk assessors, we present a Berkeley Madonna recoded version of the human physiologically based pharmacokinetic (PBPK) model used by the U.S. Environmental Protection Agency (EPA) in the recent dioxin assessment. This model incorporates CYP1A2 induction, which is an important metabolic vector that drives dioxin distribution in the human body, and it uses a variable eliminationmore » half-life that is body burden dependent. To evaluate the model accuracy, the recoded model predictions were compared with those of the original published model. The simulations performed with the recoded model matched well with those of the original model. The recoded model was then applied to available data sets of real life exposure studies. The recoded model can describe acute and chronic exposures and can be useful for interpreting human biomonitoring data as part of an overall dioxin and/or dioxin-like compounds risk assessment. - Highlights: • The best available dioxin PBPK model for interpreting human biomonitoring data is presented. • The original PBPK model was recoded from acslX to the Berkeley Madonna (BM) platform. • Comparisons were made of the accuracy of the recoded model with the original model. • The model is a useful addition to the ATSDR's BM based PBPK toolkit that supports risk assessors. • The application of the model to real-life exposure data sets is illustrated.« less

Application of Site-Specific Calibration Data Using the CALUX by XDS Bioassay for Dioxin-Like Chemicals in Soil and Sediment Samples

EPA Science Inventory

The Chemically-Activated LUciferase gene eXpression (CALUX®) by Xenobiotic Detection Systems (XDS) bioassay was evaluated for determining the presence of dioxin and dioxin-like compounds in soil and sediment in two studies conducted under the U.S. Environmental Protection Agency...

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

Environmental health risk assessment of dioxin in foods at the two most severe dioxin hot spots in Vietnam.

PubMed

Tuyet-Hanh, Tran Thi; Minh, Nguyen Hung; Vu-Anh, Le; Dunne, Michael; Toms, Leisa-Maree; Tenkate, Thomas; Thi, Minh-Hue Nguyen; Harden, Fiona

2015-07-01

Bien Hoa and Da Nang airbases were bulk storages for Agent Orange during the Vietnam War and currently are the two most severe dioxin hot spots. This study assesses the health risk of exposure to dioxin through foods for local residents living in seven wards surrounding these airbases. This study follows the Australian Environmental Health Risk Assessment Framework to assess the health risk of exposure to dioxin in foods. Forty-six pooled samples of commonly consumed local foods were collected and analyzed for dioxin/furans. A food frequency and Knowledge-Attitude-Practice survey was also undertaken at 1000 local households, various stakeholders were involved and related publications were reviewed. Total dioxin/furan concentrations in samples of local "high-risk" foods (e.g. free range chicken meat and eggs, ducks, freshwater fish, snail and beef) ranged from 3.8 pg TEQ/g to 95 pg TEQ/g, while in "low-risk" foods (e.g. caged chicken meat and eggs, seafoods, pork, leafy vegetables, fruits, and rice) concentrations ranged from 0.03 pg TEQ/g to 6.1 pg TEQ/g. Estimated daily intake of dioxin if people who did not consume local high risk foods ranged from 3.2 pg TEQ/kg bw/day to 6.2 pg TEQ/kg bw/day (Bien Hoa) and from 1.2 pg TEQ/kg bw/day to 4.3 pg TEQ/kg bw/day (Da Nang). Consumption of local high risk foods resulted in extremely high dioxin daily intakes (60.4-102.8 pg TEQ/kg bw/day in Bien Hoa; 27.0-148.0 pg TEQ/kg bw/day in Da Nang). Consumption of local "high-risk" foods increases dioxin daily intakes far above the WHO recommended TDI (1-4 pg TEQ/kg bw/day). Practicing appropriate preventive measures is necessary to significantly reduce exposure and health risk. Copyright © 2015 Elsevier GmbH. All rights reserved.

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.

A full-scale study on thermal degradation of polychlorinated dibenzo- p-dioxins and dibenzofurans in municipal solid waste incinerator fly ash and its secondary air pollution control in China.

PubMed

Gao, Xingbao; Ji, Bingjing; Yan, Dahai; Huang, Qifei; Zhu, Xuemei

2017-04-01

Degradation of polychlorinated dibenzo- p-dioxins and dibenzofurans in municipal solid waste incinerator fly ash is beneficial to its risk control. Fly ash was treated in a full-scale thermal degradation system (capacity 1 t d -1 ) to remove polychlorinated dibenzo- p-dioxins and dibenzofurans. Apart from the confirmation of the polychlorinated dibenzo- p-dioxin and dibenzofuran decomposition efficiency, we focused on two major issues that are the major obstacles for commercialising this decomposition technology in China, desorption and regeneration of dioxins and control of secondary air pollution. The toxic equivalent quantity values of polychlorinated dibenzo- p-dioxins and dibenzofurans decreased to <6 ng kg -1 and the detoxification rate was ⩾97% after treatment for 1 h at 400 °C under oxygen-deficient conditions. About 8.49% of the polychlorinated dibenzo- p-dioxins and dibenzofurans in toxic equivalent quantity (TEQ) of the original fly ash were desorbed or regenerated. The extreme high polychlorinated dibenzo- p-dioxin and dibenzofuran levels and dibenzo- p-dioxin and dibenzofuran congener profiles in the dust of the flue gas showed that desorption was the main reason, rather than de novo synthesis of polychlorinated dibenzo- p-dioxins and dibenzofurans in the exhaust pipe. Degradation furnace flue gas was introduced to the municipal solid waste incinerator economiser, and then co-processed in the air pollution control system. The degradation furnace released relatively large amounts of cadmium, lead and polychlorinated dibenzo- p-dioxins and dibenzofurans compared with the municipal solid waste incinerator, but the amounts emitted to the atmosphere did not exceed the Chinese national emission limits. Thermal degradation can therefore be used as a polychlorinated dibenzo- p-dioxin and dibenzofuran abatement method for municipal solid waste incinerator source in China.

Prenatal dioxin exposure and neurocognitive development in Hong Kong 11-year-old children.

PubMed

Hui, Lai Ling; Lam, Hugh Simon; Lau, Esther Yuet Ying; Nelson, Edmund Anthony Severn; Wong, Tze Wai; Fielding, Richard

2016-10-01

In utero exposure to dioxins and related compounds have been associated with adverse neurocognitive development in infants. It is unclear whether neurodevelopmental deficits persist to childhood. We assessed the association of prenatal dioxin exposure with neurocognitive function in 11-year-old children, and to test whether the association is modified by duration of breastfeeding. In this prospective study of 161 children born in Hong Kong in 2002, prenatal dioxin exposure was proxied by the dioxin toxicity equivalence (TEQ) in breast milk collected during the early postnatal period as determined by the Chemical-Activated LUciferase gene eXpression (CALUX) bioassay. We used multivariate linear regression analyses to assess the association of prenatal dioxin exposure with the performance on the Wechsler Intelligence Scale for Children-IV, Hong Kong, the Hong Kong List Learning Test, the Tests for Everyday Attention for Children and the Grooved Pegboard Test, adjusting for child's sex, mother's place of birth, mother's habitual seafood consumption, mother's age at delivery and socioeconomic position. Measures of neurocognitive and intellectual function, including full-scale IQ, fine motor coordination, verbal and non-verbal reasoning, learning ability and attention at 11 years old did not show significant variations with prenatal dioxin exposures (proxied by CALUX-TEQ total dioxin load in early breast milk). None of these associations varied by breastfeeding duration or sex. Neurocongitive function, as measured with psychological tests, in 11-year-old children was not associated with prenatal dioxin exposure to background levels of dioxins in the 2000s in Hong Kong. Copyright © 2016 Elsevier Inc. All rights reserved.

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.

Risk assessment of dioxins and dioxin-like PCBs in food--comments by the German Federal Environmental Agency.

PubMed

Gies, Andreas; Neumeier, Günther; Rappolder, Marianne; Konietzka, Rainer

2007-04-01

Human health risk assessments for dioxins and dioxin-like PCBs (with the exception of the one by US-EPA) recommend health based exposure limits within the range of 1-4 pg WHO-TEQ/kg bw per day. As all humans are exposed to measurable levels of dioxins and related substances, the determination of the tolerated daily intake is a very significant decision and may influence limit values guiding risk reduction measures and target levels. The proposed TDI has to protect all human subpopulations. In the case of dioxin this is particularly important as the exposure of infants through breast-feeding may exceed the exposure of adults by one or two orders of magnitude. An overview of recently recommended limit values (WHO, SCF, JECFA) for PCDDs, PCDFs and dioxin-like PCBs using WHO-TEFs shows the common feature that the values were derived only from non carcinogenic endpoints. In November 2000 the Scientific Committee on Food of the European Commission published an 'Opinion of the SCF on the Risk Assessment of Dioxins and Dioxin-like PCBs in Food' [SCF, Scientific Committee on Food 2000. Opinion of the SCF on the risk assessment of dioxins and dioxin-like PCBs in food. European Commission, Brussels, Adopted on November 2000 http://europa.eu.int/comm/food/fs/sc/scf/out78_en.pdf]. On the basis of this extensive review of data and experimental results the Committee recommended a temporary tolerable weekly intake (t-TWI) of 7 pg WHO-TEQ/kg bw. Only six months later the SCF carried out a re-evaluation of its t-TWI from November 2000. The reconsideration of 'pivotal studies' led to the situation that the re-assessment is now based only on rat studies which investigated only reproductive effects only on male offspring and, in addition, three of these studies are single dose studies at gestational day 15. Applying an overall uncertainty factor of 10 to the LOAEL derived estimated human daily intakes (EHDI) the SCF concluded that 14 pg/kg bw per week should be considered as a tolerable intake for 2,3,7,8-TCDD. The SCF stated that on a body weight basis, the dioxin intake of breast-fed infants has been estimated to be one to two orders of magnitude higher than the average adult intake. Recent German data suggest that the body burden of formerly breast-fed children aged 9-11 is still about 30% higher than those of their formula-fed age-mates. As breast-feeding has measurable benefits for neurological and immunological development, formula feeding cannot be recommended as an alternative to lower dioxin intake. So the only remaining way to lower the dioxin uptake is to drastically reduce the background exposure of the general population. It is acknowledged that any recommendation of a precise number for a TDI is flawed by uncertainties and the possibility of different weight being given to the studies of relevance. The determination of the TDI has influence on all regulatory limit values that are based on the TDI value. A higher TDI lowers the level of protection for humans. It is proposed by the German Federal Environmental Agency that the TDI should be reassessed in a process transparent to the public and on the basis of all relevant endpoints from animal experiments and human epidemiology, including the assessment of cancer risks.

A TIME-TRENDS STUDY OF THE OCCURRENCES AND LEVELS OF CDDS, CDFS AND DIOXIN-LIKE PCBS IN SEDIMENT CORES FROM 11 GEOGRAPHICALLY DISTRIBUTED LAKES IN THE U.S.

EPA Science Inventory

Polychlorinated dibenzo-p-dioxins (CDDs), polychlorinated dibenzofurans (CDFs) and certain non- and mono-ortho substituted polychlorinated biphenyls (cp-PCBs) are a general class of chlorinated aromatic compounds that are considered as dioxin-like. Because these chemicals are hi...

An Exploratory Study: Assessment of Modeled Dioxin ...

EPA Pesticide Factsheets

EPA announced the availability of the final report, An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios. This report investigates the potential dioxin exposure to artists/hobbyists who use ball clay to make pottery and related products. Dermal, inhalation, and ingestion exposures to clay were measured at the ceramics art department of Ohio State University in Columbus, OH. The exposure estimates were based on measured levels of clay in the studio air, deposited on surrogate food samples and on the skin of the artists. The purpose of this report is to describe an exploratory investigation of potential dioxin exposures to artists/hobbyists who use ball clay to make pottery and related products.

Dioxin-like Compounds in Lake Fish Species: Evaluation by DR-CALUX Bioassay.

PubMed

Sciuto, S; Prearo, M; Desiato, R; Bulfon, C; Burioli, E A V; Esposito, G; Guglielmetti, C; Dell'atti, L; Ru, G; Volpatti, D; Acutis, P L; Martucci, F

2018-05-01

Fish consumption is the principal source of intake of organochlorinated compounds in humans. Compared with other types of foods of animal origin, fish contain the highest levels of polychlorinated biphenyls (PCBs), polychlorinated dibenzo- p-dioxins, and polychlorinated dibenzofurans, all of which are classified as highly toxic organochlorine compounds. Currently, lakes and fish farms in northern Italy are not regularly monitored for PCBs and dioxins in areas contaminated by industrial sources, partially because of the high costs of traditional analytical methods that limit the number of samples to be analyzed. The DR-CALUX cell bioassay is based on the uptake of the cellular aryl hydrocarbon receptor (AhR) for dioxins and dioxin-like compounds. The aim of this study was to assess the levels of dioxins and dioxin-like PCB contamination in Lake Maggiore and Lake Como, two lakes in northwestern Italy, and in nearby areas. The levels were quantified using the cell bioassay DR-CALUX and reference controls in two wild fish species, perch ( Perca fluviatilis) and roach ( Rutilus rutilus), and in a farmed species, rainbow trout ( Oncorhynchus mykiss). Tissue samples collected from the farmed rainbow trout were also submitted to immunohistochemical analysis of CYP1A expression as a marker for environmental pollutant-induced liver damage. The levels of dioxins, furans, and dioxin-like PCBs were all below the maximum levels and action limits set by European Union Regulation, suggesting no risk for human health associated with the consumption of the fish species caught or farmed in these areas.

Dioxin inhalation doses from wood combustion in indoor cookfires

NASA Astrophysics Data System (ADS)

Northcross, Amanda L.; Katharine Hammond, S.; Canuz, Eduardo; Smith, Kirk R.

2012-03-01

Approximately 3 billion people worldwide rely on solid biomass fuels for household cooking and space heating, and approximately 50-60% use wood, often indoors in poorly ventilated situations. Daily exposures to high concentrations of smoke from cookstoves inside kitchens create large smoke exposures for women cooks and their small children. The smoke from burning the wood fuel contains hundred of toxic compounds, including dioxins and furans some of the most toxic compounds known to science. Health effects from exposure to dioxins include reproductive and developmental problems, damage the immune system, interference with hormones and also cause cancer. This study measured concentrations of dioxins and furans in a typical Guatemalan village home during open cookfires. Measured concentrations averaged 0.32 ± 0.07 ng m-3 over 31 fires. A Monte Carlo simulation was conducted using parameter estimates based on 8 years of research experience in the study area. The estimated total daily intake of 17 particle phase dioxin and furans for women, a 5-year-old child and a 6-month-old infant were 1.2 (S.D. = 0.4), 1.7 (S.D. = 0.7) and 2.0 (S.D. = 0.5) respectively. The 46% of babies have and estimated total daily intake (TDI) which exceed the WHO TDI guideline for dioxins and furans, 3% of women and 26% of 5-year-old children based solely inhalation of particle phase dioxins in woodsmoke from an open cooking fire. These values maybe underestimates, as they did not include gas phase concentrations or ingestion of dioxins and furans through food, which is the largest route of exposure in the developed world.

A MIXTURE OF DIOXINS, FURANS, AND NON-ORTHO PCBS BASED UPON CONCENSUS TOXIC EQUIVLENCY FACTORS PRODUCES DIOXIN-LIKE REPRODUCTIVE EFFECTS

EPA Science Inventory

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD; dioxin) and related polyhalogenated aromatic hydrocarbons (PHAHs) alter the reproductive development of laboratory animals. Therefore, we exposed animals to a mixture of dioxin and dioxin-like compounds including TCDD, 1,2,3,7,8-pentachl...

PCB 126 and Other Dioxin-Like PCBs Specifically Suppress Hepatic PEPCK Expression via the Aryl Hydrocarbon Receptor

PubMed Central

Zhang, Wenshuo; Sargis, Robert M.; Volden, Paul A.; Carmean, Christopher M.; Sun, Xiao J.; Brady, Matthew J.

2012-01-01

Dioxins and dioxin-like compounds encompass a group of structurally related heterocyclic compounds that bind to and activate the aryl hydrocarbon receptor (AhR). The prototypical dioxin is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a highly toxic industrial byproduct that incites numerous adverse physiological effects. Global commercial production of the structurally similar polychlorinated biphenyls (PCBs), however, commenced early in the 20th century and continued for decades; dioxin-like PCBs therefore contribute significantly to total dioxin-associated toxicity. In this study, PCB 126, the most potent dioxin-like PCB, was evaluated with respect to its direct effects on hepatic glucose metabolism using primary mouse hepatocytes. Overnight treatment with PCB 126 reduced hepatic glycogen stores in a dose-dependent manner. Additionally, PCB 126 suppressed forskolin-stimulated gluconeogenesis from lactate. These effects were independent of acute toxicity, as PCB 126 did not increase lactate dehydrogenase release nor affect lipid metabolism or total intracellular ATP. Interestingly, provision of cells with glycerol instead of lactate as the carbon source completely restored hepatic glucose production, indicating specific impairment in the distal arm of gluconeogenesis. In concordance with this finding, PCB 126 blunted the forskolin-stimulated increase in phosphoenolpyruvate carboxykinase (PEPCK) mRNA levels without affecting glucose-6-phosphatase expression. Myricetin, a putative competitive AhR antagonist, reversed the suppression of PEPCK induction by PCB 126. Furthermore, other dioxin-like PCBs demonstrated similar effects on PEPCK expression in parallel with their ability to activate AhR. It therefore appears that AhR activation mediates the suppression of PEPCK expression by dioxin-like PCBs, suggesting a role for these pollutants as disruptors of energy metabolism. PMID:22615911

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.

Dioxin Toxicity In Vivo Results from an Increase in the Dioxin-Independent Transcriptional Activity of the Aryl Hydrocarbon Receptor

PubMed Central

Céspedes, Miguel Angel; Galindo, Maximo Ibo; Couso, Juan Pablo

2010-01-01

The Aryl hydrocarbon receptor (Ahr) is the nuclear receptor mediating the toxicity of dioxins -widespread and persistent pollutants whose toxic effects include tumor promotion, teratogenesis, wasting syndrome and chloracne. Elimination of Ahr in mice eliminates dioxin toxicity but also produces adverse effects, some seemingly unrelated to dioxin. Thus the relationship between the toxic and dioxin-independent functions of Ahr is not clear, which hampers understanding and treatment of dioxin toxicity. Here we develop a Drosophila model to show that dioxin actually increases the in vivo dioxin-independent activity of Ahr. This hyperactivation resembles the effects caused by an increase in the amount of its dimerisation partner Ahr nuclear translocator (Arnt) and entails an increased transcriptional potency of Ahr, in addition to the previously described effect on nuclear translocation. Thus the two apparently different functions of Ahr, dioxin-mediated and dioxin-independent, are in fact two different levels (hyperactivated and basal, respectively) of a single function. PMID:21079739

Increased levels of dioxin-like substances in adipose tissue in patients with deep infiltrating endometriosis.

PubMed

Martínez-Zamora, M A; Mattioli, L; Parera, J; Abad, E; Coloma, J L; van Babel, B; Galceran, M T; Balasch, J; Carmona, F

2015-05-01

Are the levels of biologically active and the most toxic dioxin-like substances in adipose tissue of patients with deep infiltrating endometriosis (DIE) higher than in a control group without endometriosis? DIE patients have higher levels of dioxins and polychlorinated biphenyls (PCBs) in adipose tissue compared with controls without endometriosis. Some studies have investigated the levels of dioxin-like substances, in serum samples, in patients with endometriosis, with inconsistent results. Case-control study including two groups of patients. The study group (DIE group) consisted of 30 patients undergoing laparoscopic surgery because of DIE. In all patients, an extensive preoperative work-up was performed including clinical exploration, magnetic resonance imaging (MRI) and transvaginal sonography. All patients with DIE underwent a confirmatory histological study for DIE after surgery. The non-endometriosis control group (control group), included the next consecutive patient undergoing laparoscopic surgery in our center due to adnexal benign gynecological disease (ovarian or tubal procedures other than endometriosis) after each DIE patient, and who did not present any type of endometriosis. During the surgical procedure 1-2 g of adipose tissue from the omentum were obtained. Dioxin-like substances were analyzed in adipose tissue in DIE patients and controls without endometriosis. The total toxic equivalence and concentrations of both dioxins and PCBs were significantly higher in patients with DIE in comparison with the control group (P < 0.05), mainly due to the significantly higher values of the two most toxic dioxins (2,3,7,8-tetrachlorodibenzo-p-dioxin [2,3,7,8-TCDD] and 1,2,3,7,8-pentachlorodibenzo-p-dioxin [1,2,3,7,8-PeCDD]) (P < 0.01 for each compound). The levels of furan 2,3,4,7,8-PeCDF were statistically higher in the DIE group compared with controls. Only four congeners of PCBs had toxic equivalence values and concentrations that were statistically higher in patients with DIE, but these included the most toxic and carcinogenic PCB-126 (PCB-114 P < 0.05; PCB-156 P < 0.05; PCB-189 P = 0.04; PCB-126 P < 0.01). Since few patients were recruited, the study is only exploratory. Our results need to be confirmed in larger and more heterogeneous population studies since environmental and even genetic factors involved in determining dioxins and PCBs widely vary in different countries. Furthermore, the strict eligibility criteria used may preclude generalization of the results to other populations and the surgery-based sampling frame may induce a selection bias. Finally, adipose tissue was obtained only from the omentum, and not from other adipose tissue of the body. Our results suggest a potential role of dioxin-like substances in the pathogenesis of DIE. Further studies are warranted to confirm our findings. None. Not applicable. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Neurodevelopmental retardation, as assessed clinically and with magnetoencephalography and electroencephalography, associated with perinatal dioxin exposure.

PubMed

Ten Tusscher, G W; Leijs, M M; de Boer, L C C; Legler, J; Olie, K; Spekreijse, H; van Dijk, B W; Vulsma, T; Briët, J; Ilsen, A; Koppe, J G

2014-09-01

In 1980s Western Europe, human perinatal exposure to background levels of dioxins was rather high. We therefore evaluated the neurodevelopment of our cohort during the prepubertal period and in adolescence. At prepubertal age (7-12 years) 41 children were tested. Both neuromotor functioning and psychological testing were performed (Dutch version of the Wechsler Intelligence Scale for Children (WISC-R) and the Dutch version of the Child Behavior Checklist for ages 4-18 years (CBCL 4-18) and the Teacher Report Form (TRF)). Neurophysiological tests were performed using magnetoencephalography and electroencephalography. In adolescence (14-18 years) the behavior of 33 children was studied again (CBCL and TRF). And the levels of dioxins and dioxin-like PCBs (dl-PCBs) were measured in serum. At prepubertal age no association was found between perinatal dioxin exposure and verbal, performal and total IQ or with the Touwen's test for neuromotor development. There were behavioral problems associated with both prenatal and postnatal dioxin exposure. In adolescence there were problems associated with the current dioxin levels and dioxin-like-PCBs. Neurophysiological tests revealed clear negative dysfunction. An increase in latency time after a motion stimulus (N2b) of 13 ms (= a delay of 10%) is associated with the higher prenatal dioxin exposure. A similar delay was measured in testing cognitive ability by analyzing the odd ball measurements, N200 and P300, together with an amplitude decrease of 12 %. The delay is indicative of a defective myelinisation and the decrease in amplitude of a loss of neurons. We found effects on behavior in association with the perinatal dioxin exposure and in adolescence in association with the current dioxin levels. Neurophysiological testing is instrumental in the detection of effects of perinatal background levels of chemicals on brain development in normal, healthy children. The clinical, neurological and psychological tests commonly used are not sensitive enough to detect important effects. Copyright © 2014 Elsevier B.V. All rights reserved.

An Exploratory Study: Assessment of Modeled Dioxin in ...

EPA Pesticide Factsheets

The purpose of this project is to investigate the potential dioxin exposure to artists/hobbyists who use ball clay to make pottery and related products. This project will focus on artists working in a ceramics studio where exposure could occur via three pathways: particle inhalation, incidental ingestion and dermal contact. Levels of clay will be measured in the studio air, deposition surfaces and skin of artists. It is anticipated that no samples will need to be analyzed for dioxin. Rather, all samples will be analyzed for total clay levels and theoretical dioxin exposures would be estimated using information on historical measurements of dioxin levels in ball clay. Data gathering completed in 2004, internal review of report completed in Summer 2005, external peer review completed in 2007, final in 2008. See www.epa.gov/ncea for final report The purpose of this project is to investigate the potential dioxin exposure to artists/hobbyists who use ball clay to make pottery and related products.

Reproduction of European eel jeopardised by high levels of dioxins and dioxin-like PCBs?

PubMed

Geeraerts, C; Focant, J-F; Eppe, G; De Pauw, E; Belpaire, C

2011-09-01

Dioxins, furans and dioxin-like polychlorinated biphenyls (PCBs) were analysed in muscle tissue from yellow phased European eel (Anguilla anguilla) from 38 sites in Belgium. Dioxin concentrations in eel vary considerably between sampling locations, indicating that yellow eel is a good indicator of local pollution levels. Measured levels of dioxin-like PCBs are much higher than those of the dioxins and furans. In the majority of the sites, eel has levels considered to be detrimental for their reproduction. Field levels of dioxin and dioxin-like PCBs are therefore suggested as an additional causal factor contributing to the decline of the European eel. 42% of the sampling sites show especially dioxin-like PCB levels exceeding the European consumption level (with a factor 3 on average). Human consumption of eel, especially in these highly contaminated sites, seems unjustified. Copyright © 2011 Elsevier B.V. All rights reserved.

ASSESSMENT OF THE POTENTIAL FOR TRANSPORT OF ...

EPA Pesticide Factsheets

Dioxins are very toxic contaminants and warrant study under a variety of experimental conditions. Studies were performed to evaluate the mobility of several of the dioxins in both soil columns as well as in batch experiments. The studies showed that the amount of chlorination did not necessarily control the partitioning of the dioxins, as expected, but also suggested that the structure or location where the Cl ion was attached to the benzene ring modified the hydrophobicity of the compound. Studies were performed with a variety of cosolvents which might mediate the movement of the Dioxin. The observed modification in mobility was consistent with existing theory for enhanced mobility with truly miscible solvents. Experimental data appears to show reversibility in the sorption process, but significantly limited by kinetics with 30 to 50 days reguired to release 50-90% of the contaminant. present information

Dioxin (TCDD) Induces Epigenetic Transgenerational Inheritance of Adult Onset Disease and Sperm Epimutations

PubMed Central

Manikkam, Mohan; Tracey, Rebecca; Guerrero-Bosagna, Carlos; Skinner, Michael K.

2012-01-01

Environmental compounds can promote epigenetic transgenerational inheritance of adult-onset disease in subsequent generations following ancestral exposure during fetal gonadal sex determination. The current study examined the ability of dioxin (2,3,7,8-tetrachlorodibenzo[p]dioxin, TCDD) to promote epigenetic transgenerational inheritance of disease and DNA methylation epimutations in sperm. Gestating F0 generation females were exposed to dioxin during fetal day 8 to 14 and adult-onset disease was evaluated in F1 and F3 generation rats. The incidences of total disease and multiple disease increased in F1 and F3 generations. Prostate disease, ovarian primordial follicle loss and polycystic ovary disease were increased in F1 generation dioxin lineage. Kidney disease in males, pubertal abnormalities in females, ovarian primordial follicle loss and polycystic ovary disease were increased in F3 generation dioxin lineage animals. Analysis of the F3 generation sperm epigenome identified 50 differentially DNA methylated regions (DMR) in gene promoters. These DMR provide potential epigenetic biomarkers for transgenerational disease and ancestral environmental exposures. Observations demonstrate dioxin exposure of a gestating female promotes epigenetic transgenerational inheritance of adult onset disease and sperm epimutations. PMID:23049995

Carry-over of dioxins and PCBs from feed and soil to eggs at low contamination levels-- influence of mycotoxin binders on the carry-over from feed to eggs.

PubMed

Hoogenboom, L A P; Kan, C A; Zeilmaker, M J; Van Eijkeren, J; Traag, W A

2006-05-01

Laying hens were fed with compound feed containing six different levels of dioxins, dioxin-like PCBs and indicator PCBs for a period of 56 days. This was followed by a period of 56 days on clean feed. Dioxin levels in feed varied from background levels to three times the current EU tolerance limit of 0.75 ng TEQ/kg. At all dose levels a rapid increase was observed in the dioxin levels in eggs. There was a clear linear dose-response relationship between the dioxin levels in eggs and feed. The feed containing 0.4 ng TEQ dioxins per kg resulted in egg levels just above the EU limit of 3 pg TEQ/g fat. Dioxin-like and indicator PCB residues followed a pattern very similar to that of dioxins. Exposure to the highest indicator PCB level of 32 microg/kg resulted in egg levels around 300 ng/g fat. Exposure to dioxins through contaminated soil, mixed at 10% into the feed, resulted in a similar carry-over as from feed. Mycotoxin binders, mixed at 0.5% into the feed, had little effect on the carry-over of dioxins from the feed to the egg. It can be concluded that consumption of feed or soil with even moderate levels of dioxins and dioxin-like PCBs rapidly results in increased levels in eggs. The current EU dioxin limit for feed cannot guarantee egg dioxin levels below the EU-limit.

Spatial variations in the incidence of breast cancer and potential risks associated with soil dioxin contamination in Midland, Saginaw, and Bay Counties, Michigan, USA

PubMed Central

Dai, Dajun; Oyana, Tonny J

2008-01-01

Background High levels of dioxins in soil and higher-than-average body burdens of dioxins in local residents have been found in the city of Midland and the Tittabawassee River floodplain in Michigan. The objective of this study is threefold: (1) to evaluate dioxin levels in soils; (2) to evaluate the spatial variations in breast cancer incidence in Midland, Saginaw, and Bay Counties in Michigan; (3) to evaluate whether breast cancer rates are spatially associated with the dioxin contamination areas. Methods We acquired 532 published soil dioxin data samples collected from 1995 to 2003 and data pertaining to female breast cancer cases (n = 4,604) at ZIP code level in Midland, Saginaw, and Bay Counties for years 1985 through 2002. Descriptive statistics and self-organizing map algorithm were used to evaluate dioxin levels in soils. Geographic information systems techniques, the Kulldorff's spatial and space-time scan statistics, and genetic algorithms were used to explore the variation in the incidence of breast cancer in space and space-time. Odds ratio and their corresponding 95% confidence intervals, with adjustment for age, were used to investigate a spatial association between breast cancer incidence and soil dioxin contamination. Results High levels of dioxin in soils were observed in the city of Midland and the Tittabawassee River 100-year floodplain. After adjusting for age, we observed high breast cancer incidence rates and detected the presence of spatial clusters in the city of Midland, the confluence area of the Tittabawassee, and Saginaw Rivers. After accounting for spatiotemporal variations, we observed a spatial cluster of breast cancer incidence in Midland between 1985 and 1993. The odds ratio further suggests a statistically significant (α = 0.05) increased breast cancer rate as women get older, and a higher disease burden in Midland and the surrounding areas in close proximity to the dioxin contaminated areas. Conclusion These findings suggest that increased breast cancer incidences are spatially associated with soil dioxin contamination. Aging is a substantial factor in the development of breast cancer. Findings can be used for heightened surveillance and education, as well as formulating new study hypotheses for further research. PMID:18939976

A PHARMACOKINETIC MODEL FOR ESTIMATING ...

EPA Pesticide Factsheets

Empirical evidence suggests that exposure of Americans to dioxin-like compounds was low during the early decades of the 20th century, then increased during the 1940s and 1950s reaching a peak in the 1960s and 1970s, and progressively decreased to lower levels in the 1980s and 1990s. Such evidence includes dioxin analysis of carbon-dated sediment cores of lakes and rivers, preserved meat samples from different decades of the 20th century, and limited body burden measurements of dioxin-like compounds. Pinsky and Lorber (1998) summarized studies measuring 2,3,7,8-TCDD in blood and adipose tissue finding a range of 10-20 pg/g (ppt) lipid during the 1970s, and 2-10 ppt lipid during the 1980s. This study reviews body burdens of dioxin toxic equivalents, TEQs, to find a range from about 50-80 ppt lipid during the 1970s, 30-50 ppt lipid during the 1980s, and 10-20 ppt lipid during the 1990s (TEQs comprised of the 17 dioxin and furan congeners only). Pinsky and Lorber (1998) investigated historical exposure trends for 2,3,7,8-TCDD by using a single-compartment, first-order pharmacokinetic model. The current study extends this prior effort by modeling dioxin TEQs instead of the single compound, 2,3,7,8-TCDD. TEQs are modeled as though they are a single compound, in contrast to an approach where the individual dioxin and furan congeners are modeled separately. It was found that body burdens of TEQs during the 1970s, 80s, and 90s could be modeled by assuming a histor

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.

Dioxin emissions from a municipal solid waste incinerator and risk of invasive breast cancer: a population-based case-control study with GIS-derived exposure.

PubMed

Viel, Jean-François; Clément, Marie-Caroline; Hägi, Mathieu; Grandjean, Sébastien; Challier, Bruno; Danzon, Arlette

2008-01-28

To date, few epidemiologic studies have examined the relationship between environmental PCDD/F exposure and breast cancer in human populations. Dioxin emissions from municipal solid waste incinerators (MSWIs) are one of the major sources of environmental dioxins and are therefore an exposure source of public concern. The purpose of this study was to examine the association between dioxins emitted from a polluting MSWI and invasive breast cancer risk among women residing in the area under direct influence of the facility. We compared 434 incident cases of invasive breast cancer diagnosed between 1996 and 2002, and 2170 controls randomly selected from the 1999 population census. A validated dispersion model was used as a proxy for dioxin exposure, yielding four exposure categories. The latter were linked to individual places of residence, using Geographic Information System technology. The age distribution at diagnosis for all cases combined showed a bimodal pattern with incidence peaks near 50 and 70 years old. This prompted us to run models separately for women aged 20-59 years, and women aged 60 years or older. Among women younger than 60 years old, no increased or decreased risk was found for any dioxin exposure category. Conversely, women over 60 years old living in the highest exposed zone were 0.31 time less likely (95% confidence interval, 0.08-0.89) to develop invasive breast cancer. Before speculating that this decreased risk reflects a dioxin anti-estrogenic activity with greater effect on late-onset acquired breast cancer, some residual confounding must be envisaged.

Reproductive and Developmental Toxicity of Dioxin in Fish1

PubMed Central

King-Heiden, Tisha C.; Mehta, Vatsal; Xiong, Kong M.; Lanham, Kevin A.; Antkiewicz, Dagmara S.; Ganser, Alissa; Heideman, Warren

2011-01-01

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD or dioxin) is a global environmental contaminant and the prototypical ligand for investigating aryl hydrocarbon receptor (AHR)-mediated toxicity. Environmental exposure to TCDD results in developmental and reproductive toxicity in fish, birds and mammals. To resolve the ecotoxicological relevance and human health risks posed by exposure to dioxin-like AHR agonists, a vertebrate model is needed that allows for toxicity studies at various levels of biological organization, assesses adverse reproductive and developmental effects and establishes appropriate integrative correlations between different levels of effects. Here we describe the reproductive and developmental toxicity of TCDD in feral fish species and summarize how using the zebrafish model to investigate TCDD toxicity has enabled us to characterize the AHR signaling in fish and to better understand how dioxin-like chemicals induce toxicity. We propose that such studies can be used to predict the risks that AHR ligands pose to feral fish populations and provide a platform for integrating risk assessments for both ecologically relevant organisms and humans. PMID:21958697

Mortality risk among workers with exposure to dioxins.

PubMed

Collins, J J; Bodner, K M; Aylward, L L; Bender, T J; Anteau, S; Wilken, M; Bodnar, C M

2016-12-01

In several studies, dioxin exposure has been associated with increased risk from several causes of death. To compare the mortality experience of workers exposed to dioxins during trichlorophenol (TCP) and pentachlorophenol (PCP) production to that of the general population and to examine mortality risk by estimated exposure levels. A retrospective cohort study which followed up workers' vital status from 1940 to 2011, with serum surveys to support estimation of historical dioxin exposure levels. Among the 2192 study subjects, there were nine deaths in TCP workers from acute non-lymphatic leukaemia [standardized mortality ratio (SMR) = 2.88, 95% confidence interval (CI) 1.32-5.47], four mesothelioma deaths (SMR = 5.12, 95% CI 1.39-13.10) and four soft tissue sarcoma (STS) deaths (SMR = 3.08, 95% CI 0.84-7.87). In PCP workers, there were eight deaths from non-Hodgkin's lymphoma (SMR = 1.92, 95% CI 0.83-3.79), 150 from ischaemic heart disease (SMR = 1.20, 95% CI 1.01-7.89) and five from stomach ulcers (SMR = 3.38, 95% CI 1.10-7.89). There were no trends of increased mortality with increased dioxin exposure except for STS and 2,3,7,8-tetrachlorodibenzo-p-dioxin levels. This finding for STS should be interpreted with caution due to the small number of deaths and the uncertainty in diagnosis and nosology. While some causes of death were greater than expected, this study provides little evidence of increased risk when dioxin exposures are considered. © The Author 2016. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Perinatal dioxin exposure and psychosocial and behavioral development in school-aged children.

PubMed

Kono, Yumi; Oka, Akira; Tada, Hiroshi; Itabashi, Kazuo; Matsui, Eiko; Nakamura, Yosikazu

2015-09-01

The aim of this study was to elucidate the association between psychosocial and behavioral problems in children at school age and dioxin level in breast milk or estimated dioxin exposure (EDE) through breastfeeding in the general Japanese population. Dioxin level of breast milk at 1month of age and breastfeeding ratio through the first year of life were used to calculate the EDE of infants born in 1998-2005 in Japan. The Japanese Social Difficulties Questionnaire (SDQ) for the assessment of children's behavior was sent by mail to mothers whose breast milk underwent the dioxin survey, at the time when their infants were aged 6-13 years. The study subjects were 175 pairs of mothers and their first infants (79 boys, 96 girls). The mean total dioxin levels of breast milk were 18.3 and 19.8 (pgTEQ/g fat) and EDEs were 16.4 and 19.6 (ngTEQ/kg/year) in boys and girls, respectively. In linear multiple regression analyses after adjusting for age at SDQ, maternal age, birth weight and maternal smoking habit, dioxin level in breast milk was not significantly related to the total difficulties score (TDS) of SDQ in boys, B=2.29 (95% CI -7.60-12.18), or in girls, B=-1.04 (95% CI -9.24-7.15). EDE correlated to the TDS in neither boys, B=-0.99 (95% CI -4.14-2.15), nor girls, B=1.08 (95% CI -2.69-4.85). No evidence was found of a correlation between perinatal dioxin exposure and behavioral and psychosocial problems of children measured by SDQ. These results support the benefits of recommending breastfeeding. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Quantification of Hydroxylated Polybrominated Diphenyl Ethers (OH-BDEs), Triclosan, and Related Compounds in Freshwater and Coastal Systems

PubMed Central

Kerrigan, Jill F.; Engstrom, Daniel R.; Yee, Donald; Sueper, Charles; Erickson, Paul R.; Grandbois, Matthew; McNeill, Kristopher; Arnold, William A.

2015-01-01

Hydroxylated polybrominated diphenyl ethers (OH-BDEs) are a new class of contaminants of emerging concern, but the relative roles of natural and anthropogenic sources remain uncertain. Polybrominated diphenyl ethers (PBDEs) are used as brominated flame retardants, and they are a potential source of OH-BDEs via oxidative transformations. OH-BDEs are also natural products in marine systems. In this study, OH-BDEs were measured in water and sediment of freshwater and coastal systems along with the anthropogenic wastewater-marker compound triclosan and its photoproduct dioxin, 2,8-dichlorodibenzo-p-dioxin. The 6-OH-BDE 47 congener and its brominated dioxin (1,3,7-tribromodibenzo-p-dioxin) photoproduct were the only OH-BDE and brominated dioxin detected in surface sediments from San Francisco Bay, the anthropogenically impacted coastal site, where levels increased along a north-south gradient. Triclosan, 6-OH-BDE 47, 6-OH-BDE 90, 6-OH-BDE 99, and (only once) 6’-OH-BDE 100 were detected in two sediment cores from San Francisco Bay. The occurrence of 6-OH-BDE 47 and 1,3,7-tribromodibenzo-p-dioxin sediments in Point Reyes National Seashore, a marine system with limited anthropogenic impact, was generally lower than in San Francisco Bay surface sediments. OH-BDEs were not detected in freshwater lakes. The spatial and temporal trends of triclosan, 2,8-dichlorodibenzo-p-dioxin, OH-BDEs, and brominated dioxins observed in this study suggest that the dominant source of OH-BDEs in these systems is likely natural production, but their occurrence may be enhanced in San Francisco Bay by anthropogenic activities. PMID:26466159

Agreement of three interpretation systems of intrapartum foetal heart rate monitoring by different levels of physicians.

PubMed

Pruksanusak, Ninlapa; Thongphanang, Putthaporn; Chainarong, Natthicha; Suntharasaj, Thitima; Kor-Anantakul, Ounjai; Suwanrath, Chitkasaem; Petpichetchian, Chusana

2017-11-01

A prospective study was conducted in centre in Southern Thailand, to evaluate agreement in EFM interpretation among various physicians in order to find out the most practical system for daily use. We found strong agreement of very normal FHR tracings among the FIGO, NICHD 3-tier and 5-tier systems. The NICHD 3-tier was more compatible with the FIGO system than 5-tier system. Overall inter-observer agreement was moderate for the NICHD 3-tier system while inter-observer agreement of 5-tier system was fair also the intra-observer agreement was higher in the NICHD 3-tier system. So the 3-tier systems are more suitable than the 5-tier system in general obstetric practice. Impact statement What is already known on this subject: The 3-tier and 5-tier systems were widely used in general obstetrics practice. What the results of this study add: The inter- and intra-observer agreement of NICHD 3-tier system was higher than the 5-tier system. What the implications are of these findings for clinical practice and/or further research: The 3-tier systems were more suitable than the 5-tier systems in general obstetrics practice.

40 CFR Table 4 to Subpart Dddd of... - Model Rule-Toxic Equivalency Factors

Code of Federal Regulations, 2010 CFR

2010-07-01

... Rule—Toxic Equivalency Factors Dioxin/furan congener Toxic equivalency factor 2,3,7,8-tetrachlorinated dibenzo-p-dioxin 1 1,2,3,7,8-pentachlorinated dibenzo-p-dioxin 0.5 1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin 0.1 1,2,3,7,8,9-hexachlorinated dibenzo-p-dioxin 0.1 1,2,3,6,7,8-hexachlorinated dibenzo-p-dioxin...

Inverse association of highly chlorinated dioxin congeners in maternal breast milk with dehydroepiandrosterone levels in three-year-old Vietnamese children.

PubMed

Kido, Teruhiko; Honma, Seijiro; Nhu, Dang Duc; Manh, Ho Dung; Van Tung, Dao; Liang, Sun Xian; Anh, Le Thai; Okamoto, Rie; Maruzeni, Shoko; Nakagawa, Hideaki; Hung, Nguyen Ngoc; Son, Le Ke

2016-04-15

This study aims to evaluate the endocrine-disrupting effect of dioxin congeners on adrenal steroid hormones in mother-child pairs. In our previous study, we found that cortisol and cortisone levels were higher in the blood and the saliva of mothers living in a dioxin hotspot area than in mothers from a non-exposed region in Vietnam. In this follow-up study, we determined the salivary steroid hormone levels in 49 and 55 three-year-old children of these mothers in the hotspot and non-exposed region, respectively. Steroid hormones were determined by liquid chromatography-tandem mass spectrometry, and dioxin in the maternal breast milk was determined by gas chromatography-mass spectrometry. Dioxin levels in the breast milk of mothers from the hotspot (median total toxic equivalents polychlorinated dibenzodioxins/polychlorinated dibenzofurans; (TEQ PCDD/Fs) of 11pg/g lipid) were three to four times higher than those of mothers in the non-exposed region (median TEQ PCDD/Fs of 3.07pg/g lipid). Salivary dehydroepiandrosterone (DHEA) levels in children were found to be significantly lower in the hotspot than in the non-exposed region, while cortisol and cortisone levels were not different between the two regions. Highly chlorinated dioxin congeners, such as octacholorodibenzodioxin (OCDD), 1,2,3,4,6,7,8-heptacholorodibenzodioxin (HpCDD) and 1,2,3,4 (or 6), 7,8-hexachlorodibenzodioxin Hx(CDD), showed stronger inverse associations with the children's salivary DHEA than other lowly chlorinated dioxin congeners. Glucocorticoid levels in the mothers exhibited a significantly positive correlation with OCDD and HpCDD/F (polychlorinated dibenzofurans). In conclusion, highly chlorinated dioxin congeners are more strongly correlated with endocrine-disrupting effects on adrenal hormones, resulting in high cortisol levels in the mothers and low DHEA levels in their three-year-old children. Copyright © 2016 Elsevier B.V. All rights reserved.

The effects of PCBs and dioxins on child health.

PubMed

Lundqvist, Christofer; Zuurbier, Moniek; Leijs, Marike; Johansson, Carolina; Ceccatelli, Sandra; Saunders, Margaret; Schoeters, Greet; ten Tusscher, Gavin; Koppe, Janna G

2006-10-01

BACKGROUND/EXPOSURE: Dioxins and PCBs are highly persistent and highly toxic environmental pollutants which at present are derived mainly from waste incineration and food contamination. They are widespread in nature and pollute human food, including breast milk so that basically all children in Europe are exposed to measurable levels. RESULTS/TOXICITY IN CHILDREN: The toxicity of dioxins and PCBs are well described both from animal studies and from a number of human epidemiological studies including several large cohort studies. Especially developmental exposure has been shown to affect endocrine and cognitive systems negatively. Measurable outcomes include reduced IQ and changed behaviour. Foetotoxic effects with reduced birth weight and increased congenital anomalies such as cleft lip have also been described. Exposure to PCBs and dioxins must be considered also in the context of multiple exposure to several toxins simultaneously or sequentially. CONCLUSION/SUGGESTED ACTION: Some measures aimed at reducing exposure to dioxins have been partly successful in that the dioxin content of breast milk is going down. However, further steps to reduce exposure must be taken. We suggest legislative measures for reducing the re-entry of especially PCBs from waste into the environment. Individual pre-conception counselling is recommended in order to reduce developmental exposure and its consequences. Biomonitoring of the substances themselves in breast milk and foods is recommended as well as monitoring possible endocrine effects.

Dioxin risk assessment: mechanisms of action and possible toxicity in human health.

PubMed

Tavakoly Sany, Seyedeh Belin; Hashim, Rosli; Salleh, Aishah; Rezayi, Majid; Karlen, David J; Razavizadeh, Bi Bi Marzieh; Abouzari-Lotf, Ebrahim

2015-12-01

Dioxin-like compounds (DLCs) have been classified by the World Health Organization (WHO) as one of the most persistent toxic chemical substances in the environment, and they are associated with several occupational activities and industrial accidents around the world. Since the end of the 1970s, these toxic chemicals have been banned because of their human toxicity potential, long half-life, wide dispersion, and they bioaccumulate in the food web. This review serves as a primer for environmental health professionals to provide guidance on short-term risk assessment of dioxin and to identify key findings for health and exposure assessment based on policies of different agencies. It also presents possible health effects of dioxins, mechanisms of action, toxic equivalency factors (TEFs), and dose-response characterization. Key studies related to toxicity values of dioxin-like compounds and their possible human health risk were identified through PubMed and supplemented with relevant studies characterized by reviewing the reference lists in the review articles and primary literature. Existing data decreases the scope of analyses and models in relevant studies to a manageable size by focusing on the set of important studies related to the perspective of developing toxicity values of DLCs.

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 ...

A constitutively active dioxin/aryl hydrocarbon receptor induces stomach tumors

NASA Astrophysics Data System (ADS)

Andersson, Patrik; McGuire, Jacqueline; Rubio, Carlos; Gradin, Katarina; Whitelaw, Murray L.; Pettersson, Sven; Hanberg, Annika; Poellinger, Lorenz

2002-07-01

The dioxin/aryl hydrocarbon receptor (AhR) functions as a ligand-activated transcription factor regulating transcription of a battery of genes encoding xenobiotic metabolizing enzymes. Known receptor ligands are environmental pollutants including polycyclic aromatic hydrocarbons and polychlorinated dioxins. Loss-of-function (gene-disruption) studies in mice have demonstrated that the AhR is involved in toxic effects of dioxins but have not yielded unequivocal results concerning the physiological function of the receptor. Gain-of-function studies therefore were performed to unravel the biological functions of the AhR. A constitutively active AhR expressed in transgenic mice reduced the life span of the mice and induced tumors in the glandular part of the stomach, demonstrating the oncogenic potential of the AhR and implicating the receptor in regulation of cell proliferation.

Multivariate Analysis and Prediction of Dioxin-Furan ...

EPA Pesticide Factsheets

Peer Review Draft of Regional Methods Initiative Final Report Dioxins, which are bioaccumulative and environmentally persistent, pose an ongoing risk to human and ecosystem health. Fish constitute a significant source of dioxin exposure for humans and fish-eating wildlife. Current dioxin analytical methods are costly, time-consuming, and produce hazardous by-products. A Danish team developed a novel, multivariate statistical methodology based on the covariance of dioxin-furan congener Toxic Equivalences (TEQs) and fatty acid methyl esters (FAMEs) and applied it to North Atlantic Ocean fishmeal samples. The goal of the current study was to attempt to extend this Danish methodology to 77 whole and composite fish samples from three trophic groups: predator (whole largemouth bass), benthic (whole flathead and channel catfish) and forage fish (composite bluegill, pumpkinseed and green sunfish) from two dioxin contaminated rivers (Pocatalico R. and Kanawha R.) in West Virginia, USA. Multivariate statistical analyses, including, Principal Components Analysis (PCA), Hierarchical Clustering, and Partial Least Squares Regression (PLS), were used to assess the relationship between the FAMEs and TEQs in these dioxin contaminated freshwater fish from the Kanawha and Pocatalico Rivers. These three multivariate statistical methods all confirm that the pattern of Fatty Acid Methyl Esters (FAMEs) in these freshwater fish covaries with and is predictive of the WHO TE

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

Occupational exposure to dioxins by thermal oxygen cutting, welding, and soldering of metals.

PubMed

Menzel, H M; Bolm-Audorff, U; Turcer, E; Bienfait, H G; Albracht, G; Walter, D; Emmel, C; Knecht, U; Päpke, O

1998-04-01

This paper focuses on one aspect of occupational dioxin exposure that is novel and unexpected. Exposures in excess of the German threshold limit value of 50 pg international toxicity equivalent (I-TEQ)/m3 are very frequent, unpredictable, and sometimes very high--up to 6612 pg I-TEQ/m3--during thermal oxygen cutting at scrap metal and demolition sites. The same procedure involving virgin steel in steel trade and mass production of steel objects gave no such evidence, even though no final conclusions can be drawn because of the low number of samples analyzed. Low dioxin exposures during inert gas electric arc welding confirm previous literature findings, whereas soldering and thermal oxygen cutting in the presence of polyvinyl chloride give rise to concern. The consequences of occupational dioxin exposure were studied by analysis of the dioxin-blood concentration, the body burden, of men performing thermal oxygen cutting at scrap metal reclamation and demolition sites, in steel trade and producing plants as well as for industrial welders and white-collar workers. The results concerning body burdens are in excellent agreement with the dioxin exposure as characterized by dioxin air concentration in the workplace. The significant positive correlation between duration and frequency of performing thermal oxygen cutting at metal reclamation and demolition sites expressed in job-years and dioxin body burden speaks for the occupational origin of the observed overload after long times. The results reported here lead to consequences for occupational health, which are discussed and require immediate attention.

Comparative risk analysis of dioxins in fish and fine particles from heavy-duty vehicles.

PubMed

Leino, Olli; Tainio, Marko; Tuomisto, Jouni T

2008-02-01

Dioxins and airborne fine particles are both environmental health problems that have been the subject of active public debate. Knowledge on fine particles has increased substantially during the last 10 years, and even the current, lowered levels in the Europe and in the United States appear to be a major public health problem. On the other hand, dioxins are ubiquitous persistent contaminants, some being carcinogens at high doses, and therefore of great concern. Our aim was to (a) quantitatively analyze the two pollutant health risks and (b) study the changes in risk in view of the current and forthcoming EU legislations on pollutants. We performed a comparative risk assessment for both pollutants in the Helsinki metropolitan area (Finland) and estimated the health effects with several scenarios. For primary fine particles: a comparison between the present emission situation for heavy-duty vehicles and the new fine particle emission standards set by the EU. For dioxins: an EU directive that regulates commercial fishing of Baltic salmon and herring that exceed the dioxin concentration limit set for fish meat, and a derogation (= exemption) from the directive for these two species. Both of these two decisions are very topical issues and this study estimates the expected changes in health effects due to these regulations. It was found that the estimated fine particle risk clearly outweighed the estimated dioxin risk. A substantial improvement to public health could be achieved by initiating reductions in emission standards; about 30 avoided premature deaths annually in the study area. In addition, the benefits of fish consumption due to omega-3 exposure were notably higher than the potential dioxin cancer risk. Both regulations were instigated as ways of promoting public health.

Dioxin emissions from a municipal solid waste incinerator and risk of invasive breast cancer: a population-based case-control study with GIS-derived exposure

PubMed Central

Viel, Jean-François; Clément, Marie-Caroline; Hägi, Mathieu; Grandjean, Sébastien; Challier, Bruno; Danzon, Arlette

2008-01-01

Background To date, few epidemiologic studies have examined the relationship between environmental PCDD/F exposure and breast cancer in human populations. Dioxin emissions from municipal solid waste incinerators (MSWIs) are one of the major sources of environmental dioxins and are therefore an exposure source of public concern. The purpose of this study was to examine the association between dioxins emitted from a polluting MSWI and invasive breast cancer risk among women residing in the area under direct influence of the facility. Methods We compared 434 incident cases of invasive breast cancer diagnosed between 1996 and 2002, and 2170 controls randomly selected from the 1999 population census. A validated dispersion model was used as a proxy for dioxin exposure, yielding four exposure categories. The latter were linked to individual places of residence, using Geographic Information System technology. Results The age distribution at diagnosis for all cases combined showed a bimodal pattern with incidence peaks near 50 and 70 years old. This prompted us to run models separately for women aged 20–59 years, and women aged 60 years or older. Among women younger than 60 years old, no increased or decreased risk was found for any dioxin exposure category. Conversely, women over 60 years old living in the highest exposed zone were 0.31 time less likely (95% confidence interval, 0.08–0.89) to develop invasive breast cancer. Conclusion Before speculating that this decreased risk reflects a dioxin anti-estrogenic activity with greater effect on late-onset acquired breast cancer, some residual confounding must be envisaged. PMID:18226215

The influence of maternal dietary exposure to dioxins and PCBs during pregnancy on ADHD symptoms and cognitive functions in Norwegian preschool children.

PubMed

Caspersen, Ida Henriette; Aase, Heidi; Biele, Guido; Brantsæter, Anne Lise; Haugen, Margaretha; Kvalem, Helen Engelstad; Skogan, Annette Holth; Zeiner, Pål; Alexander, Jan; Meltzer, Helle Margrete; Knutsen, Helle K

2016-09-01

Polychlorinated dibenzo-p-dioxins/dibenzofurans (dioxins) and polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) with potentially adverse impact on child neurodevelopment. Whether the potential detrimental effects of dioxins and PCBs on neurodevelopment are of specific or unspecific character is not clear. The purpose of the current study was to examine the influence of maternal dietary exposure to dioxins and PCBs on ADHD symptoms and cognitive functioning in preschoolers. We aimed to investigate a range of functions, in particular IQ, expressive language, and executive functions. This study includes n=1024 children enrolled in a longitudinal prospective study of ADHD (the ADHD Study), with participants recruited from The Norwegian Mother and Child Cohort Study (MoBa). Boys and girls aged 3.5years participated in extensive clinical assessments using well-validated tools; The Preschool Age Psychiatric Assessment interview (PAPA), Stanford-Binet 5th revision (SB-5), Child Development Inventory (CDI), and Behavior Rating Inventory of Executive Function, Preschool version (BRIEF-P). Maternal dietary exposure to dioxins and PCBs was estimated based on a validated food frequency questionnaire (FFQ) answered mid-pregnancy and a database of dioxin and PCB concentrations in Norwegian foods. Exposure to dioxins and dioxin-like PCBs (dl-compounds) was expressed in total toxic equivalents (TEQ), and PCB-153 was used as marker for non-dioxin-like PCBs (ndl-PCBs). Generalized linear and additive models adjusted for confounders were used to examine exposure-outcome associations. Exposure to PCB-153 or dl-compound was not significantly associated with any of the outcome measures when analyses were performed for boys and girls together. After stratifying by sex, adjusted analyses indicated a small inverse association with language in girls. An increase in the exposure variables of 1 SD was associated with a reduction in language score of -0.2 [CI -0.4, -0.1] for PCB-153 and -0.2 [CI -0.5, -0.1] for dl-compounds in girls. For boys, exposure to PCB-153 or dl-compounds was not associated with language skills. The difference between sex-specific associations was not statistically significant (p-value=0.13). No sex-specific effects were observed for ADHD-symptoms, IQ scores, or executive functions. We found no indications that variation in current low-level exposure to PCB-153 or dl-compounds in Norway is associated with variation ADHD-symptoms, verbal/non-verbal IQ, or executive functions including working memory in preschoolers. However, our findings indicated that maternal dietary exposure to PCB-153 or dl-compounds during pregnancy was significantly associated with poorer expressive language skills in preschool girls, although the sex-specific associations were not significantly different. Copyright © 2016 Elsevier Ltd. All rights reserved.

EPA's Science Plan for Activities Related to Dioxins in the ...

EPA Pesticide Factsheets

The U.S. Environmental Protection Agency is currently addressing several issues related to dioxins and dioxin-like chemicals in the environment. These include the comprehensive human health and exposure assessment for dioxin, commonly called the dioxin reassessment and a review of dioxin soil clean-up levels currently in use across the United States. To move forward with both of these efforts, as well as other dioxin related activities, a plan with interim milestones has been developed and it is outlined below. EPA’sExposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibenzo-p-Dioxin(TCDD) and Related Compounds; Response to NAS and Completion of Dioxin Reassessment 1. EPA will release a draft report that responds to the recommendations and comments included in the National Academy of Sciences’ (NAS) 2006 review of EPA’s 2003 draft dioxin reassessment. UPDATED May 21, 2010: The draft response to comments report titled EPA’s Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments (External Review Draft) (“Draft Dioxin Reanalysis”) was completed and released for public review and comment on May 21, 2010. EPA’s National Center for Environment Assessment (NCEA) in the Office of Research and Development, will prepare a limited response to key comments and recommendations in the NAS report (draft response to comments report). The draft response will focus on dose-response

Dioxin concentrations in dietary supplements containing animal oil on the Japanese market between 2007 and 2014.

PubMed

Tsutsumi, Tomoaki; Takatsuki, Satoshi; Teshima, Reiko; Matsuda, Rieko; Watanabe, Takahiro; Akiyama, Hiroshi

2018-01-01

We determined the concentrations of dioxins (polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls) in 46 dietary supplement products, containing the oil of fish, marine mammals, or egg yolk, on the Japanese market between 2007 and 2014. Dioxins were detected in 43 of the 46 products tested at concentrations from 0.00015 to 67 pg TEQ/g. The highest concentration of dioxins was found in a shark liver oil product which varied insignificantly in five batches collected over a two-year period. The dioxin intakes from these five batches reached 2.3-2.8 pg TEQ/kg bw/day, or 58%-70%, respectively, of the Japanese tolerable daily intake (TDI) of 4 pg TEQ/kg bw/day. However, the dioxin intakes from most of the other products tested were less than 5% of the TDI. Although rare, supplements based on animal oils may contain relatively high concentrations of dioxins, leading to a substantial increase in dioxin intakes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Reduction of dioxin-like toxicity in effluents by additional wastewater treatment and related effects in fish.

PubMed

Maier, Diana; Benisek, Martin; Blaha, Ludek; Dondero, Francesco; Giesy, John P; Köhler, Heinz-R; Richter, Doreen; Scheurer, Marco; Triebskorn, Rita

2016-10-01

Efficiency of advanced wastewater treatment technologies to reduce micropollutants which mediate dioxin-like toxicity was investigated. Technologies compared included ozonation, powdered activated carbon and granular activated carbon. In addition to chemical analyses in samples of effluents, surface waters, sediments, and fish, (1) dioxin-like potentials were measured in paired samples of effluents, surface waters, and sediments by use of an in vitro biotest (reporter gene assay) and (2) dioxin-like effects were investigated in exposed fish by use of in vivo activity of the mixed-function, monooxygenase enzyme, ethoxyresorufin O-deethylase (EROD) in liver. All advanced technologies studied, based on degradation or adsorption, significantly reduced dioxin-like potentials in samples and resulted in lesser EROD activity in livers of fish. Results of in vitro and in vivo biological responses were not clearly related to quantification of targeted analytes by use of instrumental analyses. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of Tier 2 and Tier 3 Mathematics Interventions for Second Graders with Mathematics Difficulties

ERIC Educational Resources Information Center

Dennis, Minyi Shih

2015-01-01

Two studies were conducted to examine the effects of Tier 2 and Tier 3 mathematics interventions on students with mathematics learning difficulties. In the first study, the work of Bryant et al. was replicated and expanded upon by documenting the sustained effects of a Tier 2 mathematics intervention on mathematics performance by second graders.…

The effect of misunderstanding the chemical properties of environmental contaminants on exposure beliefs: A case involving dioxins

PubMed Central

Zikmund-Fisher, Brian J.; Turkelson, Angela; Franzblau, Alfred; Diebol, Julia K.; Allerton, Lindsay A.; Parker, Edith A.

2013-01-01

Chemical properties of contaminants lead them to behave in particular ways in the environment and hence have specific pathways to human exposure. If residents of affected communities lack awareness of these properties, however, they could make incorrect assumptions about where and how exposure occurs. We conducted a mailed survey of 904 residents of Midland and Saginaw counties in Michigan, USA to assess to what degree residents of a community with known dioxin contamination appear to understand the hydrophobic nature of dioxins and the implications of that fact on different potential exposure pathways. Participants assessed whether various statements about dioxins were true, including multiple statements assessing beliefs about dioxins in different types of water. Participants also stated whether they believed different exposure pathways were currently significant sources of dioxin exposure in this community. A majority of residents believed that dioxins can be found in river water that has been filtered to completely remove all particulates, well water, and even city tap water, beliefs which are incongruous with the hydrophobic nature of dioxins. Mistrust of government and personal concern about dioxins predicted greater beliefs about dioxins in water. In turn, holding more beliefs about dioxins in water predicted beliefs that drinking and touching water are currently significant exposure pathways for dioxins. Ensuring that community residents’ mental models accurately reflect the chemical properties of different contaminants can be important to helping them to adjust their risk perceptions and potentially their risk mitigation behaviors accordingly. PMID:23391895

EVALUATION OF PERSONAL COOLING DEVICES FOR A DIOXIN CLEAN-UP OPERATION

EPA Science Inventory

The study investigated the use of personal coolers to increase worker productivity and safety while working at elevated, ambient temperatures cleaning up dioxin contaminated soil.^The study included laboratory tests to measure the thermal characteristics of the chemical protectiv...

Middle School Students' Responses to Two-Tier Tasks

ERIC Educational Resources Information Center

Haja, Shajahan; Clarke, David

2011-01-01

The structure of two-tier testing is such that the first tier consists of a multiple-choice question and the second tier requires justifications for choices of answers made in the first tier. This study aims to evaluate two-tier tasks in "proportion" in terms of students' capacity to write and select justifications and to examine the effect of…

Occupational exposure to dioxins by thermal oxygen cutting, welding, and soldering of metals.

PubMed Central

Menzel, H M; Bolm-Audorff, U; Turcer, E; Bienfait, H G; Albracht, G; Walter, D; Emmel, C; Knecht, U; Päpke, O

1998-01-01

This paper focuses on one aspect of occupational dioxin exposure that is novel and unexpected. Exposures in excess of the German threshold limit value of 50 pg international toxicity equivalent (I-TEQ)/m3 are very frequent, unpredictable, and sometimes very high--up to 6612 pg I-TEQ/m3--during thermal oxygen cutting at scrap metal and demolition sites. The same procedure involving virgin steel in steel trade and mass production of steel objects gave no such evidence, even though no final conclusions can be drawn because of the low number of samples analyzed. Low dioxin exposures during inert gas electric arc welding confirm previous literature findings, whereas soldering and thermal oxygen cutting in the presence of polyvinyl chloride give rise to concern. The consequences of occupational dioxin exposure were studied by analysis of the dioxin-blood concentration, the body burden, of men performing thermal oxygen cutting at scrap metal reclamation and demolition sites, in steel trade and producing plants as well as for industrial welders and white-collar workers. The results concerning body burdens are in excellent agreement with the dioxin exposure as characterized by dioxin air concentration in the workplace. The significant positive correlation between duration and frequency of performing thermal oxygen cutting at metal reclamation and demolition sites expressed in job-years and dioxin body burden speaks for the occupational origin of the observed overload after long times. The results reported here lead to consequences for occupational health, which are discussed and require immediate attention. Images Figure 1 PMID:9599722

New strategy toward dioxin risk reduction for local residents surrounding severe dioxin hotspots in Vietnam

PubMed Central

Thi Tran, Tuyet-Hanh; Nguyen, Ngoc-Bich; Le, Vu-Anh

2013-01-01

Background A public health intervention program with active involvement of local related stakeholders was piloted in the Bien Hoa dioxin hotspot (2007–2009), and then expanded to the Da Nang dioxin hotspot in Vietnam (2009–2011). It aimed to reduce the risk of dioxin exposure of local residents through foods. This article presents the results of the intervention in Da Nang. Methodology To assess the results of this intervention program, pre- and post-intervention knowledge, attitude, and practice (KAP) surveys were implemented in 400 households, randomly selected from four wards surrounding the Da Nang Airbase in 2009 and 2011, respectively. Results After the intervention, the knowledge on the existence of dioxin in food, dioxin exposure pathways, potential high-risk foods, and preventive measures significantly increased (P<0.05). Ninety-eight percent were willing to follow advice on preventing dioxin exposure. Practices to reduce the risk of dioxin exposure also significantly improved (P<0.05). After intervention, 60.4% of households undertook exposure preventive measures, significantly higher than that of the pre-intervention survey (39.6%; χ2=40.15, P<0.001). High-risk foods had quite low rates of daily consumption (from 0 to 2.5%) and were significantly reduced (P<0.05). Conclusions This is seen as an effective intervention strategy toward reducing the risk of human exposure to dioxin at dioxin hotspots. While greater efforts are needed for remediating dioxin-polluted areas inside airbases, there is also evidence to suggest that, during the past four decades, pollution has expanded to the surrounding areas. For this reason, this model should be quickly expanded to the remaining dioxin hotspots in Vietnam to further reduce the exposure risks in other areas. PMID:23791241

Influence of combustion-originated dioxins in atmospheric deposition on water quality of an urban river in Japan.

PubMed

Minomo, Kotaro; Ohtsuka, Nobutoshi; Nojiri, Kiyoshi; Matsumoto, Rie

2018-02-01

Bulk (wet and dry) deposition samples were collected in Saitama Prefecture, Japan throughout a year (February 8, 2012 to February 7, 2013) to estimate the influence of dioxins emitting from waste incinerators on river water quality. The annual deposition flux of dioxins was 3.3ng-toxic equivalent (TEQ)/m 2 /year. Source identification using indicative congeners estimated that 82% of dioxin TEQ in the bulk deposition (2.7ng-TEQ/m 2 /year) was combustion-originated, indicating that most of the dioxins in the deposition were derived from waste incinerators. In Saitama prefecture the annual flux of combustion-originated dioxins in depositions was apparently consistent with that of dioxin emission into the air from waste incinerators. The TEQ of combustion-originated dioxins in the deposition per rainfall was 2.4pg-TEQ/L on annual average, exceeding the environmental quality standard (EQS) for water in Japan of 1pg-TEQ/L. This suggests there is a possibility that dioxins in atmospheric deposition have a significant influence on the water quality of urban rivers which rainwater directly flows into because of many paved areas in the basins. The influence of combustion-originated dioxin in the deposition on the water quality of Ayase River, an urban river heavily polluted with dioxins, was estimated at 0.29pg-TEQ/L on annual average in 2015. It seems that dioxins in atmospheric deposition from waste incinerators have a significant influence on water quality of some urban rivers via rainwater though the dioxins in the ambient air have achieved the EQS for atmosphere at all monitoring sites in Japan. Copyright © 2017. Published by Elsevier B.V.

Are dioxin-like contaminants responsible for the eel ( Anguilla anguilla) drama?

NASA Astrophysics Data System (ADS)

Palstra, A. P.; van Ginneken, V. J. T.; Murk, A. J.; van den Thillart, G. E. E. J. M.

2006-03-01

Eel populations worldwide are dangerously close to collapsing. Our study is the first to show that current levels of dioxin-like contaminants are strong candidates because of their devastating effects on development and survival of eel embryos. Female and male silver eels were artificially stimulated to maturation and reproduction by treatment with carp pituitary extracts and hCG, respectively. During maturation of female European silver eels, about 60 g fat per kg eel is incorporated in the oocytes. Together with the fat, however, persistent organic pollutants such as dioxin-like polychlorinated biphenyls (PCBs) are incorporated too. The total dioxin-like toxic potency of the individual gonad batches was determined as 2,3,7,8-tetrachlorodibenzo- p-dioxine equivalents (TEQs), using an in vitro reporter gene assay. The observed differences in development and survival showed a significant negative correlation with the TEQ levels in the gonads, already at levels far below the maximal allowable level for fish consumption, i.e., 4 ng TEQ/kg fish. The clear inverse relationship between the TEQ level and the survival period of the fertilised eggs strongly suggests that the current levels of dioxin-like compounds seriously impair the reproduction of the European eel. The peak of the environmental levels of dioxin-like PCBs and the decline of eel coincide worldwide, further suggesting that, in addition to other threats, these contaminants contributed significantly to the current collapse in eel populations.

Regulatory effects of dioxin-like and non-dioxin-like PCBs and other AhR ligands on the antioxidant enzymes paraoxonase 1/2/3.

PubMed

Shen, Hua; Robertson, Larry W; Ludewig, Gabriele

2016-02-01

Paraoxonase 1 (PON1), an antioxidant enzyme, is believed to play a critical role in many diseases, including cancer. PCBs are widespread environmental contaminants known to induce oxidative stress and cancer and to produce changes in gene expression of various pro-oxidant and antioxidant enzymes. Thus, it appeared of interest to explore whether PCBs may modulate the activity and/or gene expression of PON1 as well. In this study, we compared the effects of dioxin-like and non-dioxin-like PCBs and of various aryl hydrocarbon receptor (AhR) ligands on PON1 regulation and activity in male and female Sprague-Dawley rats. Our results demonstrate that (i) the non-dioxin-like PCB154, PCB155, and PCB184 significantly reduced liver and serum PON1 activities, but only in male rats; (ii) the non-dioxin-like PCB153, the most abundant PCB in many matrices, did not affect PON1 messenger RNA (mRNA) level in the liver but significantly decreased serum PON1 activity in male rats; (iii) PCB126, an AhR ligand and dioxin-like PCB, increased both PON1 activities and gene expression; and (iv) even though three tested AhR ligands induced CYP1A in several tissues to a similar extent, they displayed differential effects on the three PONs and AhR, i.e., PCB126 was an efficacious inducer of PON1, PON2, PON3, and AhR in the liver, while 3-methylcholantrene induced liver AhR and lung PON3, and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the most potent AhR agonist, increased only PON3 in the lung, at the doses and exposure times used in these studies. These results show that PCBs may have an effect on the antioxidant protection by paraoxonases in exposed populations and that regulation of gene expression through AhR is highly diverse.

Building Tier 3 Intervention for Long-Term Slow Growers in Grades 3-4: A Pilot Study

ERIC Educational Resources Information Center

Sanchez, Victoria M.; O'Connor, Rollanda E.

2015-01-01

Tier 3 interventions are necessary for improving the reading performance of students who fail to respond adequately to Tier 1 general education instruction and Tier 2 supplemental reading intervention. In this pilot study, we identified 8 students in 3rd and 4th grade who had demonstrated slow response to Tier 2 reading interventions for three…

Assays of dioxins and dioxin-like compounds in actually contaminated soils using transgenic tobacco plants carrying a recombinant mouse aryl hydrocarbon receptor-mediated β-glucuronidase reporter gene expression system

PubMed Central

Inui, Hideyuki; Gion, Keiko; Utani, Yasushi; Wakai, Taketo; Kodama, Susumu; Eun, Heesoo; Kim, Yun-Seok; Ohkawa, Hideo

2012-01-01

The transgenic tobacco plant XD4V-26 carrying the recombinant mouse aryl hydrocarbon receptor XD4V-mediated β-glucuronidase (GUS) reporter gene expression system was used for assay of dioxins and dioxin-like compounds consisting of polychlorodibenzo-p-dioxins, polychlorinated dibenzofurans, and coplanar polychlorinated biphenyls (Co-PCBs) in actually contaminated soils. The transgenic tobacco plant XD4V-26 showed a significant dose-dependent induced GUS activity when cultured on MS medium containing PCB126 [toxic equivalency factor (TEF) = 0.1]. In contrast, PCB169 and PCB180, which have 0.03 of TEF and unassigned TEF values, respectively, did not significantly induce GUS activity under the same conditions as with PCB126. When the tobacco plants were cultivated for up to 5 weeks on actually contaminated soils with dioxins and dioxin-like compounds collected from the periphery of an incinerator used for disposal of life and industrial wastes, GUS activity in the leaves was dose-dependently increased. The plants clearly detected 360 pg-TEQ g−1 of dioxins and dioxin-like compounds in this assay. There was a positive correlation between GUS activity and TEQ value of dioxins and dioxin-like compounds in the plants. This assay does not require any extraction and purification processes for the actually contaminated soil samples. PMID:22428884

Assays of dioxins and dioxin-like compounds in actually contaminated soils using transgenic tobacco plants carrying a recombinant mouse aryl hydrocarbon receptor-mediated β-glucuronidase reporter gene expression system.

PubMed

Inui, Hideyuki; Gion, Keiko; Utani, Yasushi; Wakai, Taketo; Kodama, Susumu; Eun, Heesoo; Kim, Yun-Seok; Ohkawa, Hideo

2012-01-01

The transgenic tobacco plant XD4V-26 carrying the recombinant mouse aryl hydrocarbon receptor XD4V-mediated β-glucuronidase (GUS) reporter gene expression system was used for assay of dioxins and dioxin-like compounds consisting of polychlorinated dibenzeno-p-dioxins, polychlorinated dibenzofurans, and coplanar polychlorinated biphenyls (Co-PCBs) in actually contaminated soils. The transgenic tobacco plant XD4V-26 showed a significant dose-dependent induced GUS activity when cultured on MS medium containing PCB126 [toxic equivalency factor (TEF) = 0.1]. In contrast, PCB169 and PCB180, which have 0.03 of TEF and unassigned TEF values, respectively, did not significantly induce GUS activity under the same conditions as with PCB126. When the tobacco plants were cultivated for up to 5 weeks on actually contaminated soils with dioxins and dioxin-like compounds collected from the periphery of an incinerator used for disposal of residential and industrial wastes, GUS activity in the leaves was dose-dependently increased. The plants clearly detected 360 pg-TEQ g(-1) of dioxins and dioxin-like compounds in this assay. There was a positive correlation between GUS activity and TEQ value of dioxins and dioxin-like compounds in the plants. This assay does not require any extraction and purification processes for the actually contaminated soil samples.

Assays of dioxins and dioxin-like compounds in actually contaminated soils using transgenic tobacco plants carrying a recombinant mouse aryl hydrocarbon receptor-mediated β-glucuronidase reporter gene expression system.

PubMed

Inui, Hideyuki; Gion, Keiko; Utani, Yasushi; Wakai, Taketo; Kodama, Susumu; Eun, Heesoo; Kim, Yun-Seok; Ohkawa, Hideo

2012-01-01

The transgenic tobacco plant XD4V-26 carrying the recombinant mouse aryl hydrocarbon receptor XD4V-mediated β-glucuronidase (GUS) reporter gene expression system was used for assay of dioxins and dioxin-like compounds consisting of polychlorodibenzo-p-dioxins, polychlorinated dibenzofurans, and coplanar polychlorinated biphenyls (Co-PCBs) in actually contaminated soils. The transgenic tobacco plant XD4V-26 showed a significant dose-dependent induced GUS activity when cultured on MS medium containing PCB126 [toxic equivalency factor (TEF) = 0.1]. In contrast, PCB169 and PCB180, which have 0.03 of TEF and unassigned TEF values, respectively, did not significantly induce GUS activity under the same conditions as with PCB126. When the tobacco plants were cultivated for up to 5 weeks on actually contaminated soils with dioxins and dioxin-like compounds collected from the periphery of an incinerator used for disposal of life and industrial wastes, GUS activity in the leaves was dose-dependently increased. The plants clearly detected 360 pg-TEQ g(-1) of dioxins and dioxin-like compounds in this assay. There was a positive correlation between GUS activity and TEQ value of dioxins and dioxin-like compounds in the plants. This assay does not require any extraction and purification processes for the actually contaminated soil samples.

DIOXINS: AN OVERVIEW

EPA Science Inventory

Introduction: Dioxins have been featured in the news recently following a poisoning incident in Europe.1-3 Because physicians are not usually taught much about the dioxins, this article attempts to provide an overview for practicing physicians. Dioxins are unwanted contaminants ...

Dioxin and Dioxin-Like Compounds Toxic Equivalency Information

EPA Pesticide Factsheets

EPA requires that, in addition to the total grams released for the entire dioxin and dioxin-like compounds category, TRI facilities must report the quantity for each individual member on a new Form R Schedule 1.

COHORT OF WOMEN LIVING IN OR NEAR A HIGHLY INDUSTRIALIZED AREA OF KANAWHA RIVER VALLEY IN WEST VIRGINIA: ENDOMETRIOSIS AND BLOOD LEVELS OF DIOXIN AND DIOXIN-LIKE CHEMICALS

EPA Science Inventory

Introduction Historical releases of dioxin and dioxin-like chemicals with subsequent impacts to environmental media in the Kanawha River Valley (KRV) of West Virginia have been well documented.' The bulk of dioxin found in this area appears to be derived from the production of 2,...

Dioxin in the river Elbe.

PubMed

Götz, Rainer; Bergemann, Michael; Stachel, Burkhard; Umlauf, Gunther

2017-09-01

This paper provides a macro-analysis of the dioxin contamination in the river Elbe from the 1940s to the present. Based on different data sets, the historic dioxin concentration in the Elbe has been reconstructed. For the section between the tributary Mulde and Hamburg, during the 1940s, we find a concentration of about 1500 pg WHO-TEQ g -1 . We argue that this dioxin contamination was caused mainly by emissions from a magnesium plant in Bitterfeld-Wolfen, whose effluents were discharged into a tributary of the river Mulde which flows into the Elbe. Dioxin pattern recognition with neural networks (Kohonen) confirms this. A model simulation shows that a hypothetical dioxin concentration of 10,000 pg WHO-TEQ g -1 in the tributary Mulde could have caused the reconstructed dioxin concentration of 1500 pg WHO-TEQ g -1 in the Elbe. The recent dioxin concentration (about 25-100 pg WHO-TEQ g -1 ) in the river Elbe, downstream the tributary Mulde, originates, according to our hypothesis, from emissions of the banks and the highly contaminated flood plains (transport of the particle bound dioxin). As other possible dioxin sources, the following could be excluded: the dioxin concentration in the Mulde, groynes, small ports, sport boat harbours, and extreme floods. Our hypothesis is supported by the results of pattern recognition techniques and a model simulation. According to these findings, we argue that remediation efforts to reduce the dioxin concentration in the river Elbe are unlikely to be successful. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dioxin formation and control in a gasification-melting plant.

PubMed

Kawamoto, Katsuya; Miyata, Haruo

2015-10-01

We investigated dioxin formation and removal in a commercial thermal waste treatment plant employing a gasification and melting process that has become widespread in the last decade in Japan. The aim was to clarify the possibility of dioxin formation in a process operation at high temperatures and the applicability of catalytic decomposition of dioxins. Also, the possible use of dioxin surrogate compounds for plant monitoring was further evaluated. The main test parameter was the influence of changes in the amount and type of municipal solid waste (MSW) supplied to the thermal waste treatment plant which from day to day operation is a relevant parameter also from commercial perspective. Here especially, the plastic content on dioxin release was assessed. The following conclusions were reached: (1) disturbance of combustion by adding plastic waste above the capability of the system resulted in a considerable increase in dioxin content of the flue gas at the inlet of the bag house and (2) bag filter equipment incorporating a catalytic filter effectively reduced the gaseous dioxin content below the standard of 0.1 ng toxic equivalency (TEQ)/m(3) N, by decomposition and partly adsorption, as was revealed by total dioxin mass balance and an increased levels in the fly ash. Also, the possible use of organohalogen compounds as dioxin surrogate compounds for plant monitoring was further evaluated. The levels of these surrogates did not exceed values corresponding to 0.1 ng TEQ/m(3) N dioxins established from former tests. This further substantiated that surrogate measurement therefore can well reflect dioxin levels.

Effects of perinatal exposure to PCBs and dioxins on play behavior in Dutch children at school age.

PubMed

Vreugdenhil, Hestien J I; Slijper, Froukje M E; Mulder, Paul G H; Weisglas-Kuperus, Nynke

2002-10-01

Polychlorinated biphenyls (PCBs) and dioxins are known as neurotoxic compounds that may modulate sex steroid hormones. Steroid hormones play a mediating role in brain development and may influence behaviors that show sex differences, such as childhood play behavior. In this study we evaluated the effects of perinatal exposure to environmental levels of PCBs and dioxins on childhood play behavior and whether the effects showed sex differences. As part of the follow-up to the Dutch PCB/dioxin study at school age, we used the Pre-School Activity Inventory (PSAI) to assess play behavior in the Rotterdam cohort (n = 207). The PSAI assesses masculine or feminine play behavior scored on three subscales: masculine, feminine, and composite. Prenatal exposure to PCBs was defined as the sum of PCB 118, 138, 153, and 180 in maternal and cord plasma and breast milk. For breast milk we measured additional PCBs as well as 17 dioxins. Respondents returned 160 questionnaires (age 7.5 years +/- 0.4). Effects of prenatal exposure to PCBs, measured in maternal and cord plasma, on the masculine and composite scales were different for boys and girls (p <.05). In boys, higher prenatal PCB levels were related with less masculinized play, assessed by the masculine scale (p(maternal) =.042; p(cord) =.001) and composite scale (p(cord) =.011), whereas in girls higher PCB levels were associated with more masculinized play, assessed by the composite scale (p(PCBmilk) =.028). Higher prenatal dioxin levels were associated with more feminized play in boys as well as girls, assessed by the feminine scale (p =.048). These effects suggest prenatal steroid hormone imbalances caused by prenatal exposure to environmental levels of PCBs, dioxins, and other related organochlorine compounds.

A rapid and reagent-free bioassay for the detection of dioxin-like compounds and other aryl hydrocarbon receptor (AhR) agonists using autobioluminescent yeast.

PubMed

Xu, Tingting; Young, Anna; Marr, Enolia; Sayler, Gary; Ripp, Steven; Close, Dan

2018-02-01

An autonomously bioluminescent Saccharomyces cerevisiae BLYAhS bioreporter was developed in this study for the simple and rapid detection of dioxin-like compounds (DLCs) and aryl hydrocarbon receptor (AhR) agonists. This recombinant yeast reporter was based on a synthetic bacterial luciferase reporter gene cassette (lux) that can produce the luciferase as well as the enzymes capable of self-synthesizing the requisite substrates for bioluminescent production from endogenous cellular metabolites. As a result, bioluminescent signal production is generated continuously and autonomously without cell lysis or exogenous reagent addition. By linking the expression of the autobioluminescent lux reporter cassette to AhR activation via the use of a dioxin-responsive promoter, the S. cerevisiae BLYAhS bioreporter emitted a bioluminescent signal in response to DLC exposure in a dose-responsive manner. The model dioxin, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), could be detected within 4 h with a half maximal effective concentration (EC 50 ) of ~ 8.1 nM and a lower detection limit of 500 pM. The autobioluminescent response of BLYAhS to other AhR agonists, including 2,3,7,8-tetrachlorodibenzofuran (TCDF), polychlorinated bisphenyl congener 126 (PCB-126) and 169 (PCB-169), 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin (HxCDD), 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (HpCDD), benzo[a]pyrene (BaP), and β-naphthoflavone (bNF), were also characterized in this study. The non-destructive and reagent-free nature of the BLYAhS reporter assay facilitated near-continuous, automated signal acquisition without additional hands-on effort and cost, providing a simple and cost-effective method for rapid DLC detection.

Alterations in the programming of energy metabolism in adolescents with background exposure to dioxins, dl-PCBs and PBDEs.

PubMed

Leijs, Marike M; Koppe, Janna G; Vulsma, Thomas; Olie, Kees; van Aalderen, Wim M C; de Voogt, Pim; Legler, Juliette; Ten Tusscher, Gavin W

2017-01-01

Dioxins and PCBs are highly toxic and persistent environmental pollutants that are measurable in humans worldwide. These persistent organic pollutants are associated with a higher incidence of diabetes mellitus. We hypothesise that perinatal (background) exposure to industrial pollutants like dioxins also influences body mass development and energy metabolism in later life. In The Netherlands, the perinatal exposure (prenatal exposure and postnatal lactational intake) to dioxins has been studied prospectively since 1987. Fasting glucose, insulin, HbA1c and leptin were analysed in 33 children of the original cohort of 60. BMI, glucose:insulin and BMI:leptin ratios were calculated. Prenatal exposure, lactational intake and current serum levels of dioxins (PCDD/F), dl-PCBs and PBDE concentrations were determined using (HR)GC-MS. Prenatal dioxin (PCDD/F) exposure was positively correlated to the glucose:insulin ratio (p = 0.024) and negatively correlated to the fasting insulin concentration (p = 0.017) in adolescence. Postnatal lactational PCDD/F intake was also negatively correlated to fasting insulin concentration (p = 0.028). Current serum levels of PCDD/Fs and total TEQ (dl-PCBs+PCDD/Fs) were positively correlated to the fasting serum glucose concentration (p = 0.015 and p = 0.037, respectively).No metabolic effects were seen in association with current serum levels of PBDEs. A positive correlation between the insulin and leptin concentrations (p = 0.034) was observed. No effects were found on leptin levels, BMI:leptin ratio, HbA1c levels or BMI. This study indicates that prenatal and lactational exposure influences glucose metabolism in adolescents, presumably through a negative effect on insulin secretion by pancreatic beta cells. Additionally, the very low recent background exposure to dioxins in puberty possibly has an effect on the glucose level.

Dioxins, furans and dioxin-like PCBs in sediment samples and suspended particulate matter from the Scheldt estuary and the North Sea Coast: Comparison of CALUX concentration levels in historical and recent samples.

PubMed

Vandermarken, T; Gao, Y; Baeyens, W; Denison, M S; Croes, K

2018-06-01

The Scheldt estuary is historically a highly polluted river system. While several studies have focused on contamination with metals, pesticides, Polycyclic Aromatic Hydrocarbons (PAHs) and marker PolyChlorinated Biphenyls (PCBs), no data are available concerning past contamination by dioxin-like compounds. The objective of this study is to determine spatial and time trends of PolyChlorinated Dibenzo-p-Dioxins and DibenzoFurans (PCDD/Fs) and dioxin-like PCBs (dl-PCBs) in sediment samples and Suspended Particulate Matter (SPM) from the Scheldt River basin and the North Sea Coast. Dioxin-like compounds (PCDD/F and dl-PCB fractions) were measured with the CALUX-bioassay. Bioanalytical EQuivalent concentrations (BEQs) and Total Organic Carbon (TOC) content of historical (1982-1984) and recent (2011-2015) sediment and SPM samples from different locations in the coastal area and the estuary, were evaluated. A decrease in dioxin-like compound concentrations was found at all stations over time, especially for the PCDD/Fs. Dl-PCBs were relatively low in all samples. The Scheldt mouth and the Antwerp harbor yielded the highest BEQs and levels were higher in SPM than in sediment due to the higher organic carbon content in this fraction. Current PCDD/F and dl-PCB levels in the Belgian Coastal Zone and Scheldt estuary are much lower than their levels 30 years ago and pose a relatively low risk to the aquatic system. This is the result of a strong decrease in emissions, however, large local variabilities in sediment concentration levels can still exist because of local variability in sedimentation, erosion rates and in organic carbon content. Copyright © 2018 Elsevier B.V. All rights reserved.

Cross-sectional Associations between Exposure to Persistent Organic Pollutants and Leukocyte Telomere Length among U.S. Adults in NHANES, 2001–2002

PubMed Central

Mitro, Susanna D.; Birnbaum, Linda S.; Needham, Belinda L.; Zota, Ami R.

2015-01-01

Background: Exposure to persistent organic pollutants (POPs) such as dioxins, furans, and polychlorinated biphenyls (PCBs) may influence leukocyte telomere length (LTL), a biomarker associated with chronic disease. In vitro research suggests dioxins may bind to the aryl hydrocarbon receptor (AhR) and induce telomerase activity, which elongates LTL. However, few epidemiologic studies have investigated associations between POPs and LTL. Objectives: We examined the association between 18 PCBs, 7 dioxins, and 9 furans and LTL among 1,330 U.S. adults from NHANES 2001–2002. Methods: We created three summed POP metrics based on toxic equivalency factor (TEF), a potency measure including affinity for the AhR: a) non–dioxin-like PCBs (composed of 10 non–dioxin-like PCBs; no AhR affinity and no TEF); b) non-ortho PCBs (composed of 2 non–ortho-substituted PCBs with high TEFs); and c) toxic equivalency (TEQ) (composed of 7 dioxins, 9 furans, 2 non–ortho-substituted PCBs, and 6 mono–ortho-substituted PCBs; weighted by TEF). We tested the association between each metric and LTL using linear regression, adjusting for demographics, blood cell count and distribution, and another metric with a different TEF (i.e., non-ortho PCBs and TEQ adjusted for non–dioxin-like PCBs; non–dioxin-like PCBs adjusted for non-ortho PCBs). Results: In adjusted models, each doubling of serum concentrations of non-ortho PCBs and TEQ was associated with 3.74% (95% CI: 2.10, 5.40) and 5.29% (95% CI: 1.66, 9.05) longer LTLs, respectively. Compared with the lowest quartile, the highest quartile of exposure was associated with 9.16% (95% CI: 2.96, 15.73) and 7.84% (95% CI: –0.53, 16.92) longer LTLs, respectively. Non–dioxin-like PCBs were not associated with LTL. Conclusions: POPs with high TEFs and AhR affinity were associated with longer LTL. Because many dioxin-associated cancers are also associated with longer LTL, these results may provide insight into the mechanisms underlying PCB- and dioxin-related carcinogenesis. Citation: Mitro SD, Birnbaum LS, Needham BL, Zota AR. 2016. Cross-sectional associations between exposure to persistent organic pollutants and leukocyte telomere length among U.S. adults in NHANES, 2001–2002. Environ Health Perspect 124:651–658; http://dx.doi.org/10.1289/ehp.1510187 PMID:26452299

RISK CHARACTERIZATION OF DIOXINS

EPA Science Inventory

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD; "Dioxin") is the most toxic member of a family of structurally related compounds which are ubiquitous environmental pollutants. The most potent of these, the polyhalogenated dibenzo-p-dioxins and furans, were never produced int...

40 CFR Table 3 to Subpart Cccc of... - Toxic Equivalency Factors

Code of Federal Regulations, 2010 CFR

2010-07-01

... Table 3 to Subpart CCCC of Part 60—Toxic Equivalency Factors Dioxin/furan congener Toxic equivalency factor 2,3,7,8-tetrachlorinated dibenzo-p-dioxin 1 1,2,3,7,8-pentachlorinated dibenzo-p-dioxin 0.5 1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin 0.1 1,2,3,7,8,9-hexachlorinated dibenzo-p-dioxin 0.1 1,2,3,6...

40 CFR Table 2 of Subpart Ec to... - Toxic Equivalency Factors

Code of Federal Regulations, 2010 CFR

2010-07-01

... Ec to Part 60—Toxic Equivalency Factors Dioxin/furan congener Toxic equivalency factor 2,3,7,8-tetrachlorinated dibenzo-p-dioxin 1 1,2,3,7,8-pentachlorinated dibenzo-p-dioxin 0.5 1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin 0.1 1,2,3,7,8,9-hexachlorinated dibenzo-p-dioxin 0.1 1,2,3,6,7,8-hexachlorinated dibenzo...

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.

Limited mobility of dioxins near San Jacinto super fund site (waste pit) in the Houston Ship Channel, Texas due to strong sediment sorption.

PubMed

Louchouarn, Patrick; Seward, Shaya M; Cornelissen, Gerard; Arp, Hans Peter H; Yeager, Kevin M; Brinkmeyer, Robin; Santschi, Peter H

2018-07-01

Sediments from a waste pit in Houston Ship Channel (HSC) were characterized using a number of molecular markers of natural organic matter fractions (e.g., pyrogenic carbon residues, PAHs, lignins), in addition to dioxins, in order to test the hypothesis that the dispersal and mobility of dioxins from the waste pit in the San Jacinto River is minimal. Station SG-6, sampled at the site of the submerged waste pit, had the highest dioxin/furan concentrations reported for the Houston Ship Channel/Galveston Bay (HSC/GB) system (10,000-46,000 pg/g), which translated into some of the highest reported World Health Organization Toxic Equivalents (TEQs: 2000-11,000 pg/g) in HSC sediments. Using a multi-tracer approach, this study confirmed our hypothesis that sludges from chlorinated pulps are a very likely source of dioxins/furans to this pit. However, this material also contained large quantities of additional hydrophobic organic contaminants (PAHs) and pyrogenic markers (soot-BC, levoglucosan), pointing to the co-occurrence of petroleum hydrocarbons and combustion byproducts. Comparison of dioxin/furan signatures in the waste pit with those from sediments of the HSC and a control site suggests that the remobilization of contaminated particles did not occur beyond the close vicinity of the pit itself. The dioxins/furans in sediments outside the waste pit within the HSC are rather from other diffuse inputs, entering the sedimentary environment through the air and water, and which are comprised of a mixture of industrial and municipal sources. Fingerprinting of waste pit dioxins indicates that their composition is typical of pulp and paper sources. Measured pore water concentrations were 1 order of magnitude lower than estimated values, calculated from a multiphase sorption model, indicating low mobility of dioxins within the waste pit. This is likely accomplished by co-occurring and strong sorbing pyrogenic and petrogenic residues in the waste pit, which tend to keep dioxins strongly sorbed to particles. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Dioxins and dioxin-like chemicals in blood and semen of American Vietnam veterans from the state of Michigan.

PubMed

Schecter, A; McGee, H; Stanley, J S; Boggess, K; Brandt-Rauf, P

1996-12-01

This exposure assessment pilot study tested the hypothesis that elevated blood levels of the dioxin congener 2,3,7,8-TCDD ("TCDD"), due to Agent Orange exposure, in American Vietnam veterans could be demonstrated two to three decades after Vietnam service. A second objective was to determine if dioxins, including TCDD, are present in the semen of adult males. In the early 1990s, blood samples from 50 Vietnam veterans and three pooled semen samples from 17 of them were analyzed by high-resolution gas chromatography-mass spectroscopy for dioxins, dibenzofurans, and the dioxin-like PCBs. Fifty volunteers from the Michigan Vietnam veteran bonus list, which documented Vietnam service, were invited to participate based on their self-reported exposure to Agent Orange in Vietnam. Screening of military and medical records was performed by an epidemiologist and a physician to assure that Agent Orange exposure was possible based on job description, location of service in Vietnam, and military Agent Orange spray records. Elevated 2,3,7,8-TCDD levels, over 20 ppt on a lipid basis, could still be detected in six of the 50 veterans in this nonrandomly selected group. The dioxin and dibenzofuran congeners commonly found in the U.S. population, including TCDD, were also detected in the three pooled semen samples. Quantification and comparison on a lipid basis were not possible due to low lipid concentrations where levels were below the detection limit. Therefore, semen samples were measured and reported on a wet-weight basis. Elevated blood TCDD levels, probably related to Agent Orange exposure, can be detected between two and three decades after potential exposure in some American veterans. Original levels were estimated to be 35-1,500-fold greater that that of the general population (4 ppt, lipid) at the time of exposure. In addition, the detection of dioxins in semen suggests a possible mechanism for male-mediated adverse reproductive outcomes following Agent Orange or other dioxin exposure.

Impact of iron and steel industry and waste incinerators on human exposure to dioxins, PCBs, and heavy metals: results of a cross-sectional study in Belgium.

PubMed

Fierens, Sébastien; Mairesse, Hélène; Heilier, Jean-François; Focant, Jean-François; Eppe, Gauthier; De Pauw, Edwin; Bernard, Alfred

2007-02-01

We evaluated the impact of two iron and steel plants and two municipal solid waste incinerators (MSWI) in Wallonia (Belgium) on the exposure of residents to dioxins, polychlorinated biphenyls (PCBs), and heavy metals. In total, 142 volunteers living around these facilities were recruited and compared with 63 referents from a rural area with no industrial source of pollution. Information about smoking habits, dietary habits, anthropometric characteristics, residential history, and health status was obtained from a self-administered questionnaire. The volunteers provided blood under fasting conditions in order to evaluate the body burden of dioxins (17 polychlorinated dibenzo-p-dioxins/dibenzofurans [PCDD/Fs] congeners) and PCBs. Samples of blood and urine were also taken for the determination of cadmium, mercury, and lead. After adjustment for covariates, concentrations of cadmium, mercury, and lead in urine or blood were not increased in subjects living in the vicinity of MSWIs or sinter plants by comparison with referents. Residents around the sinter plants and the MSWI located in the industrial area had concentrations of dioxins and PCBs in serum similar to that of referents. By contrast, subjects living in the vicinity of the MSWI in the rural area showed significantly higher serum levels of dioxins (geometric mean, 38 vs. 24 pg TEQ/g fat) and coplanar PCBs (geometric mean, 10.8 vs. 7.0 pg TEQ/g fat). Although age-adjusted dioxin levels in referents did not vary with local animal fat consumption, concentrations of dioxins in subjects living around the incinerators correlated positively with their intake of local animal fat, with almost a doubling in subjects with the highest fat intake. These results indicate that dioxins and coplanar PCBs emitted by MSWIs can indeed accumulate in the body of residents who regularly consume animal products of local origin.

RISK CHARACTERIZATION OF DIOXINS FOR EUROTOX 2005

EPA Science Inventory

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD or Dioxin) is the most toxic member of a family of structurally related compounds which are ubiquitous environmental pollutants. The most potent of these classes, the polyhalogenated dibenzo-p-dioxins and furans, were never produced in...

ENVIRONMENTAL TECHNOLOGY VERIFICATION (ETV) TEST OF DIOXIN EMISSION MONITORS

EPA Science Inventory

The performance of four dioxin emission monitors including two long-term sampling devices, the DMS (DioxinMonitoringSystem) and AMESA (Adsorption Method for Sampling Dioxins and Furans), and two semi-real-time continuous monitors, RIMMPA-TOFMS (Resonance Ionization with Multi-Mir...

Dioxin Exposure and Age of Pubertal Onset among Russian Boys

PubMed Central

Lee, Mary M.; Williams, Paige L.; Sergeyev, Oleg; Burns, Jane S.; Patterson, Donald G.; Turner, Wayman E.; Needham, Larry L.; Altshul, Larisa; Revich, Boris; Hauser, Russ

2011-01-01

Background: Animal data demonstrate associations of dioxin, furan, and polychlorinated biphenyl (PCB) exposures with altered male gonadal maturation. It is unclear whether these associations apply to human populations. Objectives: We investigated the association of dioxins, furans, PCBs, and corresponding toxic equivalent (TEQ) concentrations with pubertal onset among boys in a dioxin-contaminated region. Methods: Between 2003 and 2005, 499 boys 8–9 years of age were enrolled in a longitudinal study in Chapaevsk, Russia. Pubertal onset [stage 2 or higher for genitalia (G2+) or testicular volume (TV) > 3 mL] was assessed annually between ages 8 and 12 years. Serum levels at enrollment were analyzed by the Centers for Disease Control and Prevention, Atlanta, Georgia, USA. We used Cox proportional hazards models to assess age at pubertal onset as a function of exposure adjusted for potential confounders. We conducted sensitivity analyses excluding boys with pubertal onset at enrollment. Results: The median (range) total serum TEQ concentration was 21 (4–175) pg/g lipid, approximately three times higher than values in European children. At enrollment, boys were generally healthy and normal weight (mean body mass index, 15.9 kg/m2), with 30% having entered puberty by G2+ and 14% by TV criteria. Higher dioxin TEQs were associated with later pubertal onset by TV (hazard ratio = 0.68, 95% confidence interval, 0.49–0.95 for the highest compared with the lowest quartile). Similar associations were observed for 2,3,7,8-tetrachlorodibenzo-p-dioxin and dioxin concentrations for TV but not G2+. Results were robust to sensitivity analyses. Conclusions: Findings support an association of higher peripubertal serum dioxin TEQs and concentrations with later male pubertal onset reflected in delayed testicular maturation. PMID:21527364

CHLOROBENZENES, CHLOROPHENOLS, PAHS AND LOW CHLORINATED DIOXIN/FURAN AS POST-BOILER TOXICITY INDICATORS IN MUNICIPAL SOLID WASTE INCINERATORS

EPA Science Inventory

Numerous research studies have been conducted to establish indicator compounds for fast and less costly predictive monitoring of polychlorinated dibenzo-p-dioxin and furan (PCDD/F) toxic equivalent concentrations (TEQs). Many studies have shown that chlorobenzenes and chlorophen...

An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios (External Review Draft)

EPA Science Inventory

EPA has released an external review draft entitled, An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios(External Review Draft). The public comment period and the external peer-review workshop are separate processes that provide opportunities ...

Body burden levels of dioxin, furans, and PCBs among frequent consumers of Great Lakes sport fish

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

Falk, C.; Hanrahan, L.; Anderson, H.A.

1999-02-01

Dioxins, furans, and polychlorinated biphenyls (PCBs) are toxic, persist in the environment, and bioaccumulate to concentrations that can be harmful to humans. The Health Departments of five GL states, Wisconsin, Michigan, Ohio, Illinois, and Indiana, formed a consortium to study body burden levels of chemical residues in fish consumers of Lakes Michigan, Huron, and Erie. In Fall 1993, a telephone survey was administered to sport angler households to obtain fish consumption habits and demographics. A blood sample was obtained from a portion of the study subjects. One hundred serum samples were analyzed for 8 dioxin, 10 furan, and 4 coplanarmore » PCB congeners. Multiple linear regression was conducted to assess the predictability of the following covariates: GL sport fish species, age, BMI, gender, years sport fish consumed, and lake. Median total dioxin toxic equivalents (TEq), total furan TEq, and total coplanar PCB TEq were higher among all men than all women (P = 0.0001). Lake trout, salmon, age, BMI, and gender were significant regression predictors of log (total coplanar PCBs). Lake trout, age, gender, and lake were significant regression predictors of log (total furans). Age was the only significant predictor of total dioxin levels.« less

AN ASSESSMENT OF DIOXIN LEVELS IN PROCESSED ...

EPA Pesticide Factsheets

The presence of dioxin-like compounds in ball clay was discovered in 1996 as a result of an investigation to determine the sources of elevated levels of dioxin found in two chicken fat samples from a national survey of poultry. The investigation indicated that soybean meal added to chicken feed was the source of dioxin contamination. Further investigation showed that the dioxin contamination came from the mixing of a natural clay known as

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...

EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and ...

EPA Pesticide Factsheets

EPA is releasing for external peer review and public comment an important draft document reviewing the literature on the health effects of dioxin and related compounds (also referred to as 2,3,7,8-Tetrachlorodibenzo-p-dioxin). At the request of Administrator Jackson, EPA is in the process of re-assessing the science on the effects of dioxin, a toxic chemical that is emitted by multiple sources, on the public’s health. This draft dioxin report is EPA’s response to key comments and recommendations made by the National Academy of Sciences on the Agency’s draft dioxin reassessment. This assessment has been in progress for many years and raises health issues of broad interest to scientists and policymakers across the federal family. The Agency’s draft report includes significant new analyses on potential cancer and non-cancer human health effects that may result from exposures to dioxins and includes an oral reference dose for what is considered to be the most toxic of the dioxin-like compounds. EPA’s Science

Hospitals and plastics. Dioxin prevention and medical waste incinerators.

PubMed

Thornton, J; McCally, M; Orris, P; Weinberg, J

1996-01-01

CHLORINATED DIOXINS and related compounds are extremely potent toxic substances, producing effects in humans and animals at extremely low doses. Because these compounds are persistent in the environment and accumulate in the food chain, they are now distributed globally, and every member of the human population is exposed to them, primarily through the food supply and mothers' milk. An emerging body of information suggests that dioxin contamination has reached a level that may pose a large-scale, long-term public health risk. Of particular concern are dioxin's effects on reproduction, development, immune system function, and carcinogenesis. Medical waste incineration is a major source of dioxins. Polyvinyl chloride (PVC) plastic, as the dominant source of organically bound chlorine in the medical waste stream, is the primary cause of "iatrogenic" dioxin produced by the incineration of medical wastes. Health professionals have a responsibility to work to reduce dioxin exposure from medical sources. Health care institutions should implement policies to reduce the use of PVC plastics, thus achieving major reductions in medically related dioxin formation.

Alterations in the programming of energy metabolism in adolescents with background exposure to dioxins, dl-PCBs and PBDEs

PubMed Central

Koppe, Janna G.; Vulsma, Thomas; Olie, Kees; van Aalderen, Wim M. C.; de Voogt, Pim; Legler, Juliette; ten Tusscher, Gavin W.

2017-01-01

Objectives Dioxins and PCBs are highly toxic and persistent environmental pollutants that are measurable in humans worldwide. These persistent organic pollutants are associated with a higher incidence of diabetes mellitus. We hypothesise that perinatal (background) exposure to industrial pollutants like dioxins also influences body mass development and energy metabolism in later life. Study design In The Netherlands, the perinatal exposure (prenatal exposure and postnatal lactational intake) to dioxins has been studied prospectively since 1987. Fasting glucose, insulin, HbA1c and leptin were analysed in 33 children of the original cohort of 60. BMI, glucose:insulin and BMI:leptin ratios were calculated. Prenatal exposure, lactational intake and current serum levels of dioxins (PCDD/F), dl-PCBs and PBDE concentrations were determined using (HR)GC-MS. Results Prenatal dioxin (PCDD/F) exposure was positively correlated to the glucose:insulin ratio (p = 0.024) and negatively correlated to the fasting insulin concentration (p = 0.017) in adolescence. Postnatal lactational PCDD/F intake was also negatively correlated to fasting insulin concentration (p = 0.028). Current serum levels of PCDD/Fs and total TEQ (dl-PCBs+PCDD/Fs) were positively correlated to the fasting serum glucose concentration (p = 0.015 and p = 0.037, respectively).No metabolic effects were seen in association with current serum levels of PBDEs. A positive correlation between the insulin and leptin concentrations (p = 0.034) was observed. No effects were found on leptin levels, BMI:leptin ratio, HbA1c levels or BMI. Discussion/Conclusion This study indicates that prenatal and lactational exposure influences glucose metabolism in adolescents, presumably through a negative effect on insulin secretion by pancreatic beta cells. Additionally, the very low recent background exposure to dioxins in puberty possibly has an effect on the glucose level. PMID:28898241

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.

Estimation of Freely-Dissolved Concentrations of Polychlorinated Biphenyls, 2,3,7,8-Substituted Congeners and Homologs of Polychlorinated dibenzo-p-dioxins and Dibenzofurans in Water for Development of Total Maximum Daily Loadings for the Bluestone River Watershed, Virginia and West Virginia

USGS Publications Warehouse

Gale, Robert W.

2007-01-01

The Commonwealth of Virginia Department of Environmental Quality, working closely with the State of West Virginia Department of Environmental Protection and the U.S. Environmental Protection Agency is undertaking a polychlorinated biphenyl source assessment study for the Bluestone River watershed. The study area extends from the Bluefield area of Virginia and West Virginia, targets the Bluestone River and tributaries suspected of contributing to polychlorinated biphenyl, polychlorinated dibenzo-p-dioxin and dibenzofuran contamination, and includes sites near confluences of Big Branch, Brush Fork, and Beaver Pond Creek. The objectives of this study were to gather information about the concentrations, patterns, and distribution of these contaminants at specific study sites to expand current knowledge about polychlorinated biphenyl impacts and to identify potential new sources of contamination. Semipermeable membrane devices were used to integratively accumulate the dissolved fraction of the contaminants at each site. Performance reference compounds were added prior to deployment and used to determine site-specific sampling rates, enabling estimations of time-weighted average water concentrations during the deployed period. Minimum estimated concentrations of polychlorinated biphenyl congeners in water were about 1 picogram per liter per congener, and total concentrations at study sites ranged from 130 to 18,000 picograms per liter. The lowest concentration was 130 picograms per liter, about threefold greater than total hypothetical concentrations from background levels in field blanks. Polychlorinated biphenyl concentrations in water fell into three groups of sites: low (130-350 picogram per liter); medium (640-3,500 picogram per liter; and high (11,000-18,000 picogram per liter). Concentrations at the high sites, Beacon Cave and Beaverpond Branch at the Resurgence, were about four- to sixfold higher than concentrations estimated for the medium group of sites. Minimum estimated concentrations of polychlorinated dibenzo-p-dioxin and dibenzofuran congeners in water were about 0.2 to 1 femtograms per liter. Estimated total concentrations of 2,3,7,8-substituted congeners in water at study sites ranged from less than 1 to 22,000 femtograms per liter and less than 1 to 2,300 femtograms per liter for polychlorinated dibenzo-p-dioxin and dibenzofuran congeners, respectively. Total concentrations of 2,3,7,8-substituted congeners in water were comprised largely of octachlorodibenzo-p-dioxin and dibenzofuran, with less than 10 percent of the total contributed by concentrations of other congeners, mainly 2,3,7,8-heptachlorodibenzo-p-dioxin and dibenzofuran. Of special interest for this study was 2,3,7,8-tetrachlorodibenzo-p-dioxin with a regulatory surface water-quality criterion of 1,200 femtograms per liter. Estimated concentrations in water ranged from 0.5 to 41 femtograms per liter. Concentrations in water were less than 5 femtograms per liter at all study sites, except the Bluefield Westside Sewage Treatment Plan, with an estimated concentration of 41 femtograms per liter. Estimated total concentrations of homologs of polychlorinated dibenzo-p-dioxins and dibenzofurans in water at the study sites ranged from 3,200 to 36,000 femtograms per liter and 210-4,800 femtograms per liter, respectively. Again, homologs of polychlorinated dibenzo-p-dioxins and dibenzofurans in water were comprised largely of octachlorodibenzo-p-dioxin and dibenzofuran.

75 FR 17857 - Removal of Obsolete References to Herbicides Containing Dioxin

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-08

... Herbicides Containing Dioxin AGENCY: Department of Veterans Affairs. ACTION: Final rule. SUMMARY: The... health effects of exposure to herbicides containing dioxin and radiation to remove the obsolete references to herbicides containing dioxin. This final rule reflects changes made by the Agent Orange Act of...

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.

Tier 1 and Tier 2 Early Intervention for Handwriting and Composing

ERIC Educational Resources Information Center

Berninger, Virginia W.; Rutberg, Judith E.; Abbott, Robert D.; Garcia, Noelia; Anderson-Youngstrom, Marci; Brooks, Allison; Fulton, Cynthia

2006-01-01

Three studies evaluated Tier 1 early intervention for handwriting at a critical period for literacy development in first grade and one study evaluated Tier 2 early intervention in the critical period between third and fourth grades for composing on high stakes tests. The results contribute to knowledge of research-supported handwriting and…

The Development and Validation of a Three-Tier Diagnostic Test Measuring Pre-Service Elementary Education and Secondary Science Teachers' Understanding of the Water Cycle

ERIC Educational Resources Information Center

Schaffer, Dannah Lynn

2013-01-01

The main goal of this research study was to develop and validate a three-tier diagnostic test to determine pre-service teachers' (PSTs) conceptual knowledge of the water cycle. For a three-tier diagnostic test, the first tier assesses content knowledge; in the second tier, a reason is selected for the content answer; and the third tier allows…

Dioxins, dibenzofurans, dioxin-like PCBs, and DDE in U.S. fast food, 1995.

PubMed

Schecter, A; Li, L

1997-01-01

Food, especially dairy products, meat, and fish, is the primary source of environmental exposure to dioxins in the general population. Little data exists on dioxin levels in the popular and widely consumed "fast foods". Data presented in a previously published pilot study was limited to measuring only the levels of dioxins and dibenzofurans in three types of U.S. fast food. This study adds to the previous paper by presenting data, in addition to dioxins and dibenzofurans, on the closely related dioxin-like polychlorinated biphenyls (PCBs), and the persistent metabolite of DDT, 1,1-dichloro-2,2-bis (p-chlorophenyl) ethylene (DDE), in four types of popular U.S. fast food. These include McDonald's Big Mac Hamburger, Pizza Hut's Personal Pan Pizza Supreme, Kentucky Fried Chicken (KFC) three piece original recipe mixed dark and white meat luncheon package, and Häagen-Daz chocolate-chocolate chip ice cream. Dioxin plus dibenzofuran dioxin toxic equivalents (TEQ) ranged from 0.03 to 0.28 TEQ pg/g wet or whole weight for the Big Mac, from 0.03 to 0.29 for the Pizza, from 0.01 to 0.31 for the KFC, and from 0.03 to 0.49 TEQ pg/g for the ice cream. Daily TEQ consumption per kilogram body weight (kg/BW), assuming an average 65 kg adult and a 20 kg child, from one serving of each of these fast food ranged between 0.046 and 1.556 pg/kg in adults whereas in children the values were between 0.15 and 5.05 pg/kg. Total measured PCDD/Fs in the Big Mac, Personal Pan Pizza, KFC, and the Häagen-Daz ice cream varied from 0.58 to 9.31 pg/g. Measured DDE levels in the fast foods ranged from 180 to 3170 pg/g. Total mono-ortho PCB levels ranged up to 500 pg/g or 1.28 TEQ pg/g for the KFC and for di-ortho PCBs up to 740 pg/g or 0.014 TEQ pg/g for the pizza sample. Total PCB values in the four samples ranged up to 1170 pg/g or 1.29 TEQ pg/g for the chicken sample.

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.

EVIDENCE OF FEED CONTAMINATION DUE TO SAMPLE HANDLING AND PREPARATION DURING A MASS BALANCE STUDY OF DIOXINS IN LACTATING COWS IN BACKGROUND CONDITIONS

EPA Science Inventory

In 1997, the United States (US) Environmental Protection Agency (EPA) conducted a mass balance study of polychlorinated dibenzo-p-dioxins (CDDs) and dibenzofurans (CDFs) in lactating cows in background conditions. The field portion of the study occurred at the US Department of A...

Optimizing bulk milk dioxin monitoring based on costs and effectiveness.

PubMed

Lascano-Alcoser, V H; Velthuis, A G J; van der Fels-Klerx, H J; Hoogenboom, L A P; Oude Lansink, A G J M

2013-07-01

Dioxins are environmental pollutants, potentially present in milk products, which have negative consequences for human health and for the firms and farms involved in the dairy chain. Dioxin monitoring in feed and food has been implemented to detect their presence and estimate their levels in food chains. However, the costs and effectiveness of such programs have not been evaluated. In this study, the costs and effectiveness of bulk milk dioxin monitoring in milk trucks were estimated to optimize the sampling and pooling monitoring strategies aimed at detecting at least 1 contaminated dairy farm out of 20,000 at a target dioxin concentration level. Incidents of different proportions, in terms of the number of contaminated farms, and concentrations were simulated. A combined testing strategy, consisting of screening and confirmatory methods, was assumed as well as testing of pooled samples. Two optimization models were built using linear programming. The first model aimed to minimize monitoring costs subject to a minimum required effectiveness of finding an incident, whereas the second model aimed to maximize the effectiveness for a given monitoring budget. Our results show that a high level of effectiveness is possible, but at high costs. Given specific assumptions, monitoring with 95% effectiveness to detect an incident of 1 contaminated farm at a dioxin concentration of 2 pg of toxic equivalents/g of fat [European Commission's (EC) action level] costs €2.6 million per month. At the same level of effectiveness, a 73% cost reduction is possible when aiming to detect an incident where 2 farms are contaminated at a dioxin concentration of 3 pg of toxic equivalents/g of fat (EC maximum level). With a fixed budget of €40,000 per month, the probability of detecting an incident with a single contaminated farm at a dioxin concentration equal to the EC action level is 4.4%. This probability almost doubled (8.0%) when aiming to detect the same incident but with a dioxin concentration equal to the EC maximum level. This study shows that the effectiveness of finding an incident depends not only on the ratio at which, for testing, collected truck samples are mixed into a pooled sample (aiming at detecting certain concentration), but also the number of collected truck samples. In conclusion, the optimal cost-effective monitoring depends on the number of contaminated farms and the concentration aimed at detection. The models and study results offer quantitative support to risk managers of food industries and food safety authorities. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

LOW COST SOLIDIFICATION/STABILIZATION TREATMENT FOR SOILS CONTAMINATED WITH DIOXIN, PCP AND CREOSOTE

EPA Science Inventory

The USEPA's NRMRL conducted successful treatability tests of innovative solidification/stabilization (S/S) formulations to treat soils contaminated with dioxins, pentachlorophenol (PCP), and creosote from four wood preserving sites. Formulations developed during these studies wer...

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.

TECHNOLOGIES FOR MONITORING AND MEASUREMENT OF DIOXIN AND DIOXIN-LIKE COMPOUNDS IN SOIL AND SEDIMENT. HYBRIZYME CORPORATION AHRC PCR KIT

EPA Science Inventory

A demonstration of technologies for determining the presence of dioxin and dioxin-like compounds in soil and sediment was conducted under EPA's Superfund Innovative Technology Evaluation Program in Saginaw, Michigan in April 2004. This report describes the performance evaluation ...

EXPOSURE ASSESSMENT TO DIOXINS FROM THE USE OF TAMPONS AND DIAPERS

EPA Science Inventory

Exposure Assessment to Dioxins from the Use of Tampons and Diapers
Michael J. DeVito and Arnold Schecter
Abstract
Methods: Four brands of tampons and four brands of infant diapers were analyzed for dioxin concentrations. Exposures to dioxins were modeled using parti...

EXPERIMENTAL DESIGN CONSIDERATIONS WHEN VERIFYING THE PERFORMANCE OF MONITORING TECHNOLOGIES FOR DIOXIN AND DIOXIN-LIKE COMPOUNDS IN SOILS AND SEDIMENTS

EPA Science Inventory

A performance verification demonstration of technologies capable of detecting dioxin and dioxin-like compounds in soil and sediment samples was conducted in April 2004 under the U.S. Environmental Protection Agency's Superfund Innovative Technology Evaluation (SITE) Monitoring an...

A Two-Tier Multiple Choice Questions to Diagnose Thermodynamic Misconception of Thai and Laos Students

NASA Astrophysics Data System (ADS)

Kamcharean, Chanwit; Wattanakasiwich, Pornrat

The objective of this study was to diagnose misconceptions of Thai and Lao students in thermodynamics by using a two-tier multiple-choice test. Two-tier multiple choice questions consist of the first tier, a content-based question and the second tier, a reasoning-based question. Data of student understanding was collected by using 10 two-tier multiple-choice questions. Thai participants were the first-year students (N = 57) taking a fundamental physics course at Chiang Mai University in 2012. Lao participants were high school students in Grade 11 (N = 57) and Grade 12 (N = 83) at Muengnern high school in Xayaboury province, Lao PDR. As results, most students answered content-tier questions correctly but chose incorrect answers for reason-tier questions. When further investigating their incorrect reasons, we found similar misconceptions as reported in previous studies such as incorrectly relating pressure with temperature when presenting with multiple variables.

Dioxins and dibenzofurans in adipose tissue of US Vietnam veterans and controls

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

Kang, H.K.; Watanabe, K.K.; Breen, J.

1991-03-01

The primary reason for concern about the adverse effects of exposure to Agent Orange is attributable to its toxic contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or dioxin. We studied adipose tissues from 36 Vietnam veterans, a similar group of 79 non-Vietnam veterans, and 80 civilians; the tissue specimens were selected from the 8,000 archived tissues collected from the non-institutionalized general population by the US Environmental Protection Agency. The geometric mean (+/- standard deviation) dioxin levels in adipose tissue for Vietnam veterans, non-Vietnam veterans, and civilian controls were 11.7 (+/- 1.7), 10.9 (+/- 1.7), and 12.4 (+/- 1.9) parts per trillion on a lipidmore » weight basis, respectively. The mean levels for these groups were not significantly different from each other with or without adjustment for age of individuals, body mass index, and specimen collection year. In addition, none of the surrogate measures of Agent Orange exposure such as military branch, service within specific geographic region, military occupation, and troop location in relation to recorded Agent Orange spray was associated with the dioxin levels in adipose tissue of Vietnam veterans. Our results suggest that heavy exposure to Agent Orange or dioxin for most US troops was unlikely.« less

Effects of a Tier 3 Self-Management Intervention Implemented with and without Treatment Integrity

ERIC Educational Resources Information Center

Lower, Ashley; Young, K. Richard; Christensen, Lynnette; Caldarella, Paul; Williams, Leslie; Wills, Howard

2016-01-01

This study investigated the effects of a Tier 3 peer-matching self-management intervention on two elementary school students who had previously been less responsive to Tier 1 and Tier 2 interventions. The Tier 3 self-management intervention, which was implemented in the general education classrooms, included daily electronic communication between…

A STUDY TO EVALUATE THE LEVELS OF DIOXIN-LIKE COMPOUNDS IN DAIRY FEEDS IN THE U.S.

EPA Science Inventory

The Environmental Protection Agency (EPA), in cooperation with USDA and the US Food and Drug Administration (FDA), has undertaken a program to study the presence of dioxin-like compounds in animal feeds. Two phases of this program have been completed, and this paper reports on t...

The ecohydrological biotechnology (SBFS) for reduction of dioxin-induced toxicity in Asella lake, Ethiopia

NASA Astrophysics Data System (ADS)

Urbaniak, M.; Zerihun Negussie, Y.; Zalewski, M.

2012-04-01

The transfer of dioxins along river continuum is a well know process which indicated permanent increase of their content in the river sediments. Despite this, there is still lack of empirical data highlighting the role of lakes and reservoirs in dioxins transfer along river continuum. Using the ecohydrology as a framework for water problem solving, the reduction of dioxins bioaccumulation in aquatic food chain should be based on two steps: 1) a reduction of dioxins emission to the water ecosystems and 2) an understanding of the role that the factors determining dioxins accumulation, transportation and transformation in the river and lake/reservoir system play for implementation of ecohydrological biotechnologies and system solutions. From limnological perspective lakes and reservoirs are considered as traps for organic and mineral sediments and bounded with them nutrients and other polluting substances. As effect of long term ecological succession the amount of sedimented matter, nutrients and loads and concentrations of pollutants usually increases. Such situation was observed in Asella lake, located in the Arsi zone of the Oromia region about 175 kilometers from Addis Ababa, Ethiopia. As the results of above processes the high concentration of dioxin concentrations in the sediments was observed, inducing decline in the water resources use. During this study the spatial pattern of dioxins concentration and toxicity (measured as WHO TEQ concentration) in the sediments of Asella river and lake taken before (in 2009) and after (in 2010) construction of Sequentional BioFiltering System (SBFS) were compared. The determination of dioxin concentrations were followed according to US EPA 1613 and 1668 Methods. Among the samples collected in the 2009 year, the contamination of lake sediments amounted for 127.65 ng kg-1 dry weight (d.w.), whereas concentration of dioxins in samples taken at the lake outflow decreased to the value of 26.65 ng kg-1 d.w. The WHO-TEQ concentrations also showed declining tendency along the river-lake system with the highest value in the inflow (2.32 ng TEQ kg-1 d.w.), middle in the lake (1.09 ng TEQ kg-1 d.w.) and the lowest at the lake outflow (0.55 ng TEQ kg-1 d.w.). Samples collected after one year of SBFS implementation showed 70% reduction of sediment toxicity in the lake indicating positive role of such ecohydrological solution on the quality of lake ecosystem and in consequence on the human health. The obtained data indicate that the reduction of dioxins contamination in the upper part of the river by construction of the SBFS is fundamental to the improvement of the quality of the lake and lower part of the river. Implementation of such system reduced the input of dioxins to the lake through sedimentation and possibly due to acceleration of photo- and biodegradation processes and in consequence improve the quality of the whole river-lake system. The study was financed by the Ministry of Foreign Affairs of the Republic of Poland within the Polish Aid Programme 2011 project no 23/2011 and 62/2012: "Implementation of Ecohydrology - a transdisciplinary science for integrated water management and sustainable development in Ethiopia".

Global deposition of airborne dioxin.

PubMed

Booth, Shawn; Hui, Joe; Alojado, Zoraida; Lam, Vicky; Cheung, William; Zeller, Dirk; Steyn, Douw; Pauly, Daniel

2013-10-15

We present a global dioxin model that simulates one year of atmospheric emissions, transport processes, and depositions to the earth's terrestrial and marine habitats. We map starting emission levels for each land area, and we also map the resulting deposits to terrestrial and marine environments. This model confirms that 'hot spots' of deposition are likely to be in northern Europe, eastern North America, and in parts of Asia with the highest marine dioxin depositions being the northeast and northwest Atlantic, western Pacific, northern Indian Ocean and the Mediterranean. It also reveals that approximately 40% of airborne dioxin emissions are deposited to marine environments and that many countries in Africa receive more dioxin than they produce, which results in these countries being disproportionately impacted. Since human exposure to dioxin is largely through diet, this work highlights food producing areas that receive higher atmospheric deposits of dioxin than others. Copyright © 2013 Elsevier Ltd. All rights reserved.

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...

75 FR 984 - Draft Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at CERCLA and RCRA Sites

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-07

... Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at CERCLA and RCRA Sites AGENCY... Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at Comprehensive Environmental Response... interim PRGs for dioxin in soil. These draft recommended interim PRGs were calculated using existing, peer...

COMPARING ENVIRONMENTALLY RELEVANT PCBS TO TCDD IN CYP1A2 NULL AND WILDTYPE MICE

EPA Science Inventory

The role of CYP1A2 on the interactions of TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin, dioxin), dioxin-like (DL) and non-dioxin-like (NDL) polychlorinated biphenyls (PCBs) was compared in multiple responses of different laboratory-defined mixtures, based on mass ratios found in...

AN OVERVIEW OF THE AQUATIC ECOLOGICAL RISKS POSED BY DIOXIN-LIKE CHEMICALS

EPA Science Inventory

This seminar will provide a basic overview of how 2,3,7,8-tetrachlorodibenzo-p-dioxin (a.k.a. TCDD or "dioxin") and dioxin-like chemicals (e.g., certain PCBs) bioaccumulate and affect non-human receptors in aquatic food webs; the latest on applications of the toxicity equivalence...

Dioxins, Furans and PCBs in Recycled Water for Indirect Potable Reuse

PubMed Central

Rodriguez, Clemencia; Cook, Angus; Devine, Brian; Van Buynder, Paul; Lugg, Richard; Linge, Kathryn; Weinstein, Philip

2008-01-01

An assessment of potential health impacts of dioxin and dioxin-like compounds in recycled water for indirect potable reuse was conducted. Toxic equivalency factors (TEFs) for 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (PCBs) congeners have been developed by the World Health Organization to simplify the risk assessment of complex mixtures. Samples of secondary treated wastewater in Perth, Australia were examined pre-and post-tertiary treatment in one full-scale and one pilot water reclamation plant. Risk quotients (RQs) were estimated by expressing the middle-bound toxic equivalent (TEQ) and the upper-bound TEQ concentration in each sampling point as a function of the estimated health target value. The results indicate that reverse osmosis (RO) is able to reduce the concentration of PCDD, PCDF and dioxin-like PCBs and produce water of high quality (RQ after RO=0.15). No increased human health risk from dioxin and dioxin-like compounds is anticipated if highly treated recycled water is used to augment drinking water supplies in Perth. Recommendations for a verification monitoring program are offered. PMID:19151430

Loss of the Mono-ADP-ribosyltransferase, Tiparp, Increases Sensitivity to Dioxin-induced Steatohepatitis and Lethality*

PubMed Central

Ahmed, Shaimaa; Bott, Debbie; Gomez, Alvin; Tamblyn, Laura; Rasheed, Adil; Cho, Tiffany; MacPherson, Laura; Sugamori, Kim S.; Yang, Yang; Grant, Denis M.; Cummins, Carolyn L.; Matthews, Jason

2015-01-01

The aryl hydrocarbon receptor (AHR) mediates the toxic effects of the environmental contaminant dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin; TCDD). Dioxin causes a range of toxic responses, including hepatic damage, steatohepatitis, and a lethal wasting syndrome; however, the mechanisms are still unknown. Here, we show that the loss of TCDD-inducible poly(ADP-ribose) polymerase (Tiparp), an ADP-ribosyltransferase and AHR repressor, increases sensitivity to dioxin-induced toxicity, steatohepatitis, and lethality. Tiparp−/− mice given a single injection of 100 μg/kg dioxin did not survive beyond day 5; all Tiparp+/+ mice survived the 30-day treatment. Dioxin-treated Tiparp−/− mice exhibited increased liver steatosis and hepatotoxicity. Tiparp ADP-ribosylated AHR but not its dimerization partner, the AHR nuclear translocator, and the repressive effects of TIPARP on AHR were reversed by the macrodomain containing mono-ADP-ribosylase MACROD1 but not MACROD2. These results reveal previously unidentified roles for Tiparp, MacroD1, and ADP-ribosylation in AHR-mediated steatohepatitis and lethality in response to dioxin. PMID:25975270

Accumulation of persistent organic pollutants in consumers of eel from polluted rivers compared to marketable eel.

PubMed

van den Dungen, Myrthe W; Kok, Dieuwertje E; Polder, Anuschka; Hoogenboom, Ron L A P; van Leeuwen, Stefan P J; Steegenga, Wilma T; Kampman, Ellen; Murk, Albertinka J

2016-12-01

Globally, many river sediments are seriously contaminated with persistent organic pollutants (POPs) known to accumulate in aquatic food. In the Netherlands, toxicological risks of human exposure to dioxins and dioxin-like compounds led to a ban on eel fishing in the Rhine-Meuse delta. The aim of this study is to investigate differences in serum POP levels in consumers of eel from high-polluted areas and consumers of eel from low-polluted areas or aquaculture. In total 80 Dutch men were included, aged 40-70 years, with a habitual eel consumption of at least one portion (150 g) per month. Total levels of dioxins and dioxin-like compounds were measured in serum of all participants with the DR CALUX bioassay, validated with GC-MS. For a subgroup of 38 participants extensive POP measurements were performed. We revealed that consumption of eel from polluted rivers resulted in 2.5 and up to 10 times increased levels of dioxins and polychlorinated biphenyls (PCBs) respectively compared to controls. The highest PCB levels were detected for PCB 153, with a median level of 896 ng/g lipid and a maximum level of 5000 ng/g lipid in the high-exposed group. Furthermore, hydroxylated PCB metabolites (OH-PCBs: sum of 4-OH-CB107, 4-OH-CB146, 4'-OH-CB172, and 4-OH-CB187) were 8 times higher in men who consumed eel from polluted areas, and detected at levels (median 4.5 ng/g ww) reported to cause adverse health effects. Also, the majority of the perfluoroalkyl substances (PFASs) were significantly higher in consumers of eel from pullulated areas. In conclusion, this study is the first to reveal that (past) consumption of eel from polluted rivers resulted in high body burdens of dioxins, PCBs, OH-PCBs and PFASs. We confirmed the predictions made in a former risk assessment, and the high levels of dioxins and dioxin-like compounds as well as the OH-PCBs are of health concern. Copyright © 2016 Elsevier Ltd. All rights reserved.

Contaminant trends in sport fish from Lake Roosevelt and the upper Columbia River, Washington, 1994-1998

USGS Publications Warehouse

Munn, Mark D.

2000-01-01

Fish from Lake Roosevelt were first reported to contain elevated concentrations of contaminants in the early 1980?s, with mercury, dioxins and furans, and polychlorinated biphenyls (PCBs) identified as being of most concern to human health. Over the following years there were a series of studies by United States and Canadian agencies addressing contaminants in fish from both a human and environmental perspective. In the early 1990?s, industrial discharges to the Columbia River above the international boundary decreased. The dominant changes in industrial practices included a reduction in slag and effluent discharges from a lead-zinc smelter, and a reduction in dioxins and furans due to processing changes at a Canadian pulp mill. It is believed that these two alterations in industrial practices may have greatly reduced the loading of selected contaminants to the Columbia River system. In response to these recent changes, the U.S. Geological Survey initiated this present study for the purpose of determining the present concentrations of mercury, dioxins and furans, and PCBs in fish, and, if possible, to determine if concentrations have changed since the 1994 studies. All contaminant analysis was done on fish fillets in order to address human health concerns. Our study concluded that the concentrations of contaminants in fish that were identified as a potential threat to human health have either not changed since the 1994 studies, or have decreased. PCBs, as determined by Aroclor 1254, do not appear to have changed between 1994 and 1998; sources of PCBs are presently unknown. In contrast, dioxins and furans, as indicated by 2,3,7,8-TCDF, did show a significant decrease in rainbow trout fillets from 1994 to 1998. However, there was no apparent change in the average 2,3,7,8-TCDF concentrations in mountain whitefish, with the reason uncertain at this time. Average concentrations of 2,3,7,8-TCDF were higher in mountain whitefish than in rainbow trout. Toxicity equivalence concentrations (TEC) are determined by summing the relative toxicity of individual congeners of dioxins, furans, and toxic ?dioxin-like? PCB congeners in individual fish. Rainbow trout from the upper reach have higher TECs than rainbow trout from the lower reach, with trout from the upper reach having a higher percentage of the toxicity from toxic ?dioxin-like? PCBs than dioxin and furan compounds. In relation to mercury, the concentrations of total mercury in walleye have significantly decreased by about 50 percent from 1994 to 1998.

Building Tier 3 Intervention for Long-Term Slow Growers in Grades 3-4: A Pilot Study

ERIC Educational Resources Information Center

Sanchez, Victoria; O'Connor, Rollanda E.

2015-01-01

Tier 3 interventions are necessary for students who fail to respond adequately to Tier 1 general education instruction and Tier 2 supplemental reading intervention instruction. We identified 8 students in 3rd and 4th grade who had demonstrated a slow response to Tier 2 reading interventions for three years. Students participated in a…

Infant dietary exposure to dioxins and dioxin-like compounds in Greece.

PubMed

Costopoulou, Danae; Vassiliadou, Irene; Leondiadis, Leondios

2013-09-01

The dietary exposure of infants to polychlorinated dibenzo dioxins and furans (PCDD/Fs) and dioxin like polychlorinated biphenyls (dl-PCBs) is an issue of great social impact. We investigated for the first time the dietary intake of these compounds in infants living in Greece. We included in our study two age groups: 0-6 months, when infants are fed exclusively by human milk and/or formula milk, and 6 to 12 months, when solid food is introduced to nutrition. We took into consideration analytical results for PCDD/Fs and dl-PCBs concentrations in the most popular infant formulae in the Greek market, previous data for mother milk concentrations of PCDD/Fs and dl-PCBs from Greece, and finally analytical data for fat-containing food products from the Greek market. In the first study group, it was found than in infants exclusively fed by breast milk, the calculated sum of PCDD/Fs and dioxin-like PCBs (60.3-80.4 TEQ pg/kg body weight) was significantly higher than that of infants that consume a combination of human milk and formula (31.2-41.6 TEQ pg/kg body weight). In the second study group, separate daily intake estimations were performed for babies receiving human milk (estimated total daily intake 19.76-24.95 TEQ pg/kg body weight) and formula milk (estimated total daily intake 1.60-2.24 TEQ pg/kg body weight). The risks of this exposure should not be overestimated because nursing is restricted to a limited period of human life and besides, the potential consumption of higher levels of dioxin-like compounds is fully compensated by the significant benefits of breast-feeding. Copyright © 2013 Elsevier Ltd. All rights reserved.

Modeling individual exposures to ambient PM2.5 in the diabetes and the environment panel study (DEPS).

PubMed

Breen, Michael; Xu, Yadong; Schneider, Alexandra; Williams, Ronald; Devlin, Robert

2018-06-01

Air pollution epidemiology studies of ambient fine particulate matter (PM 2.5 ) often use outdoor concentrations as exposure surrogates, which can induce exposure error. The goal of this study was to improve ambient PM 2.5 exposure assessments for a repeated measurements study with 22 diabetic individuals in central North Carolina called the Diabetes and Environment Panel Study (DEPS) by applying the Exposure Model for Individuals (EMI), which predicts five tiers of individual-level exposure metrics for ambient PM 2.5 using outdoor concentrations, questionnaires, weather, and time-location information. Using EMI, we linked a mechanistic air exchange rate (AER) model to a mass-balance PM 2.5 infiltration model to predict residential AER (Tier 1), infiltration factors (F inf_home , Tier 2), indoor concentrations (C in , Tier 3), personal exposure factors (F pex , Tier 4), and personal exposures (E, Tier 5) for ambient PM 2.5 . We applied EMI to predict daily PM 2.5 exposure metrics (Tiers 1-5) for 174 participant-days across the 13 months of DEPS. Individual model predictions were compared to a subset of daily measurements of F pex and E (Tiers 4-5) from the DEPS participants. Model-predicted F pex and E corresponded well to daily measurements with a median difference of 14% and 23%; respectively. Daily model predictions for all 174 days showed considerable temporal and house-to-house variability of AER, F inf_home , and C in (Tiers 1-3), and person-to-person variability of F pex and E (Tiers 4-5). Our study demonstrates the capability of predicting individual-level ambient PM 2.5 exposure metrics for an epidemiological study, in support of improving risk estimation. Copyright © 2018. Published by Elsevier B.V.

Investigation of dioxin concentrations in the lower Roanoke River basin, North Carolina, February 26-March 7, 2001

USGS Publications Warehouse

Miller, K.F.; Walters, D.A.

2001-01-01

Dioxin is a toxic chemical that, when present in the environment, can cause cancer and birth defects in humans. Dioxin is of particular concern because concentrations of dioxin that were released into the environment many years ago remain a contributing factor to current exposure. Dioxin exposure often occurs in surface-water systems downstream from contaminated sites and is detrimental to aquatic life. For these reasons and because the U.S. Geological Survey has expertise in conducting high-volume dioxin sampling, the U.S. Environmental Protection Agency and the State of North Carolina asked the U.S. Geological Survey to collect water samples in the lower Roanoke River to be analyzed for the presence of dioxin. Water quality of the lower Roanoke River Basin in North Carolina was assessed at eight sites during February 26-March 7, 2001. Water- quality samples were collected for analysis of suspended-sediment and dioxin concentrations; high-volume (750-liter) water samples were collected for dioxin analysis. Discharge measurements were made at or near the high-volume sampling sites. Suspended-sediment sampling and water-quality measurements of specific conductance, pH, water temperature, and dissolved-oxygen concentrations made at each sampling site included multidepth measurements at two cross-section transects and hourly measurements at the point of high-volume sampling. Multidepth measurements were made near the surface, mid-depth, and near the bottom of the water column. These values were averaged for each cross section. During the sampling period, all sites sampled had dioxin concentrations above detection limits (1 part per quintillion) for both suspended and dissolved dioxin. Suspended dioxin ranged from 5.1 to 900 femtograms per liter, and dissolved dioxin values ranged from 0.31 to 41 femtograms per liter. Suspended-sediment concentrations ranged from 1.1 to 14 milligrams per liter. Specific conductance values ranges from 111 to 340 microsiemens per centimeter at 25 degrees Celsius. The range of pH values at the sampling sites was from 6.6 to 7.7. Water temperatures ranged from 8.9 to 13 degrees Celsius. Dissolved-oxygen concentrations ranged from 7.3 to 10.9 milligrams per liter.

Dioxin in the Elbe river basin: policy and science under the water framework directive 2000-2015 and toward 2021.

PubMed

Förstner, Ulrich; Hollert, Henner; Brinkmann, Markus; Eichbaum, Kathrin; Weber, Roland; Salomons, Wim

2016-01-01

A critical review of the last 25 years of dioxin policy in the Elbe river catchment is presented along seven main theses of the River Basin Community (RBC)-Elbe background document "Pollutants" for the Management Plan 2016-2021. In this period, polychlorinated dibenzodioxins/-furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) will play a major role: (i) as new priority substances for which environmental quality standards (EQSs) need to be derived (Directive 2013/39/EC); (ii) in the search for innovative solutions in sediment remediation (i.e., respecting the influence of mechanical processes; Flood Risk Directive 2007/60/EC); and (iii) as indicators at the land-sea interface (Marine Strategy Framework Directive 2008/56/EC). In the Elbe river catchment, aspects of policy and science are closely connected, which became particularly obvious in a classic example of dioxin hot spot contamination, the case of the Spittelwasser creek. Here, the "source-first principle" of the first cycle of the European Water Framework Directive (WFD) had to be confirmed in a controversy on the dioxin hot spots with Saxony-Anhalt's Agency for Contaminated Sites (LAF). At the Spittelwasser site, the move from "inside the creek" to "along the river banks" goes parallel to a general paradigm shift in retrospective risk assessment frameworks and remediation techniques for organic chemicals (Ortega-Calvo et al. 2015). With respect to dioxin, large-scale stabilization applying activated carbon additions is particularly promising. Another important aspect is the assessment of the ecotoxicology of dioxins and dl- PCBs in context of sediment mobility and flood risk assessment, which has been studied in the project framework FloodSearch. Currently, the quality goals of the WFD to reach a "good chemical status" are not met in many catchment areas because substances such as mercury do and others probably will (PCDD/Fs and dl-PCB) exceed biota-EQS values catchment area-wide. So far, relating biota-EQS values to sediment-EQSs is not possible. To overcome these limitations, the DioRAMA project was initiated, which has led to improved approaches for the assessment of dioxin-contaminated sediment using in vitro bioassays and to a robust dataset on the interrelation between dioxins and dioxin-like compounds in sediments and biota.

Atmospheric concentration of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) at Umm-Al-Aish oil field-Kuwait.

PubMed

Martínez-Guijarro, Karell; Ramadan, Ashraf; Gevao, Bondi

2017-02-01

A sampling campaign was carried out to assess the impact of the oil field activities on the concentrations of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in ambient air at Umm Al-Aish oil field in northern Kuwait. Sixteen samples were collected from March 2014 to January 2015. The concentrations of ΣPCDD/Fs were relatively high (33.6-586 fg I-TEQ/m 3 ; median: 94.7 fg I-TEQ/m 3 ; 31.2 to 516 fg WHO-TEQ 2005 /m 3 ; median: 83.7 fg WHO-TEQ 2005 /m 3 ) compared to those of dl-PCBs (3.9-36.8 WHO-TEQ 2005 /m 3 ; median 9.9 WHO-TEQ 2005 /m 3 ). A unique PCDD/F profile that was not previously reported was found. Further investigations should be conducted to establish whether the dioxin profile found in this study is specific for the desulfurization facility located in the study area or from oil flaring in the oil fields located upstream of the study area. The findings suggest that the oil field activities have a significant impact on the PCDD/F concentration in ambient air but a low or negligible influence on dl-PCBs' levels. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dioxin-like biological activity of organic extracts from sediments and fish livers sampled along the Israeli Mediterranean and Red Sea coasts.

PubMed

Yudkovski, Yana; Herut, Barak; Shefer, Edna; Tom, Moshe

2015-09-15

This study provides, for the first time, a baseline evaluation of dioxin-like biological activity in sediments and fish sampled in- and adjacent to anchorages along the Mediterranean and Red Sea coasts of Israel. It indicates the effect of past pollution, still present in the sediments of older Israeli harbors, with putative contribution of still existing sources of pollution. A commercial reporter gene bioassay was used to evaluate the biological activity of dioxin-like compounds extracted from the samples. HRGC/HRMS analysis of several samples contributed a profile of dioxin-like compounds in sediments and fish. The results point out 1,2,3,4,6,7,8-HeptaCDD, 2,3,4,6,7,8-HexaCDF, 1,2,3,4,6,7,8-HeptaCDF, РСВ-126 and РСВ-118 as major contributors to the dioxin-like activity in sediments. It indicates polychlorinated biphenyls non-selective absorption in fish livers, in contrary to a biased accumulation of poorly chlorinated and more potent dibenzodioxins and dibenzofurans. Copyright © 2015 Elsevier Ltd. All rights reserved.

SEVESO WOMEN'S HEALTH STUDY: A STUDY OF THE EFFECTS OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN ON REPRODUCTIVE HEALTH. (R824761)

EPA Science Inventory

Abstract

Although reproductive effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure have been reported in numerous investigations of animals, studies of this association in humans are limited. In 1976, an explosion in Seveso, Italy exposed the surround...

Protective effects of levamisole, acetylsalicylic acid, and α-tocopherol against dioxin toxicity measured as the expression of AhR and COX-2 in a chicken embryo model.

PubMed

Gostomska-Pampuch, Kinga; Ostrowska, Alicja; Kuropka, Piotr; Dobrzyński, Maciej; Ziółkowski, Piotr; Kowalczyk, Artur; Łukaszewicz, Ewa; Gamian, Andrzej; Całkosiński, Ireneusz

2017-04-01

Polychlorinated dibenzo-p-dioxins and dibenzofurans (dioxins) are classed as persistent organic pollutants and have adverse effects on multiple functions within the body. Dioxins are known carcinogens, immunotoxins, and teratogens. Dioxins are transformed in vivo, and interactions between the products and the aryl hydrocarbon receptor (AhR) lead to the formation of proinflammatory and toxic metabolites. The aim of this study was to determine whether α-tocopherol (vitamin E), acetylsalicylic acid (ASA), and levamisole can decrease the amount of damage caused by dioxins. Fertile Hubbard Flex commercial line chicken eggs were injected with solutions containing 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or containing TCDD and the test compounds. The chicken embryos and organs were analyzed after 7 and 13 days. The levels at which AhR and cyclooxygenase-2 (COX-2) proteins (which are induced during inflammation) were expressed were evaluated by performing immunohistochemical analyses on embryos treated with TCDD alone or with TCDD and the test compounds. TCDD caused developmental disorders and increased AhR and COX-2 expression in the chicken embryo tissues. Vitamin E, levamisole, ASA, and ASA plus vitamin E inhibited AhR and COX-2 expression in embryos after 7 days and decreased AhR and COX-2 expression in embryos after 13 days. ASA, levamisole, and ASA plus vitamin E weakened the immune response and prevented multiple organ changes. Vitamin E was not fully protective against developmental changes in the embryos.

CONGENER-SPECIFIC DETECTION OF DIOXINS USING JET-REMPI. (R827927)

EPA Science Inventory

Although 210 chemically different polychlorinated dibenzo-p-dioxin and dibenzofuran congeners can be produced during combustion, it is currently believed that fewer than 20 are toxic enough to warrant monitoring. SRI is developing a continuous emissions monitor to study...

COMPARING MIXTURES OF DIOXIN-LIKE AND NON DIOXIN-LIKE PCBS TO TCDD

EPA Science Inventory

COMPARING MIXTURES OF DIOXIN-LIKE AND NON DIOXIN-LIKE PCBS TO TCDD. D E Burgin1, J J Diliberto2 and L S Birnbaum3.1University of North Carolina/Toxicology, Chapel Hill, NC, USA; 2USEPA/ORD/NHEERL, ETD, Research Triangle Park, NC, USA; 3USEPA/ORD/NHEERL, HSD, Chapel Hill, NC, USA....

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...

75 FR 57779 - Science Advisory Board Staff Office; Notification of a Public Meeting of the SAB Dioxin Review Panel

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-22

... a Public Meeting of the SAB Dioxin Review Panel AGENCY: Environmental Protection Agency (EPA...) Staff Office announces a public meeting of the SAB Dioxin Review Panel to continue its review of EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments, External Review Draft...

Optimization of an oil leaching process to reduce the level of dioxins and dioxin-like PCBs in fishmeal.

PubMed

Oterhals, Åge; Kvamme, Bjørn

2013-05-01

Fishmeal produced from fish caught in polluted fishing areas might contain dioxins and dioxin-like polychlorinated biphenyls (PCBs) above maximum permitted levels (MPL) for use in feed. Decontamination of the fishmeal can be achieved by hexane extraction. The principal objective of this study was to optimize a more environmentally friendly alternative based on oil leaching of the moist presscake intermediate product during fishmeal manufacturing. A central composite design and response surface methodology was used to study the influence of the process variables temperature (T), presscake moisture content (MC) and leaching time (LT) on the decontamination process. A significant squared MC effect was observed, resulting in an optimum leaching rate at 27% MC. This corresponds to 5% improved dibenzo-p-dioxin/dibenzo furan (PCDD/F)-PCB toxic equivalent (TEQ) reduction compared to normal presscake (55% MC). The initial leaching rate was fast, with a TEQ reduction of 69% after only 2 min at 87 °C and 55% MC. Under the best experimental conditions (87 °C, 38% MC, 12 min LT) a TEQ reduction of 82% was achieved. Excess oil in the presscake after the leaching operation could be removed by use of a water washing step. No reduction in protein quality measured by mink digestibility could be observed. The results confirm that the oil leaching process is robust and offers easily achievable TEQ levels well below present MPLs based on process conditions normally used by the industry. Comparative effects on non-dioxin-like PCBs are expected. © 2012 Society of Chemical Industry.

RASopathic comedo-like or cystic lesions induced by Vemurafenib: A model of skin lesions similar but not identical to those induced by dioxins (MADISH).

PubMed

Kaya, G; Saxer-Sekulic, N; Kaya, A; Sorg, O; Boespflug, A; Thomas, L; Saurat, J H

2018-03-24

Patients treated with vemurafenib for metastatic melanoma often develop skin lesions similar to those observed after exposure to dioxin-like compounds. We previously called these lesions MADISH (metabolizing acquired dioxin-induced skin hamartoma) when analysing a case of acute dioxin poisoning. We performed a clinical trial aimed at comparing the skin lesions observed under vemurafenib treatment with MADISH in order to bring to light a possible cross-talk between vemurafenib and dioxin pathways. In this case-series study we explored the histological aspect of skin lesions in 10 cases treated with vemurafenib for malignant melanoma. We also analysed the ability of vemurafenib and tyrosine kinase inhibitors to induce dioxin-AhR pathway. All patients had skin lesions diagnosed as "non-inflammatory acneiform eruption" by dermatologists. These were predominantly facial with notable retro-auricular involvement and clinically compatible with chloracne/MADISH when assessed by dioxin expert. Histological analysis showed mostly comedo-like lesions and dermal cysts containing epithelial wall with basal or lateral epithelial projections and lamellar keratinization, and alterations of remaining sebaceous glands. The expression of CYP1A1, a gene highly induced following dioxin exposure, was not observed in these lesions. Vemurafenib and the tyrosine kinase inhibitors erlotinib and gefitinib did not induce CYP1A1 activity. Although the skin lesions under vemurafenib treatment were morphologically similar to MADISH, the absence of CYP1A1 expression in dermal cysts of patients and the absence of CYP1A1 activation by vemurafenib led us consider that these skin lesions were different from true MADISH and not mediated by a cross-talk of AhR signalling, but rather to a hyperactivation of PI3K-Akt pathway as a consequence of vemurafenib treatment. A strong expression of CYP1A1 in the epithelial wall of dermal cysts must be required, parallel to the morphology of the lesions, to make the diagnosis of MADISH, the hallmark of an exposure to dioxin-like/chloracnegen compounds. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

OCCURRENCE OF POLYBROMINATED BIPHENYLS, POLYBROMINATED DIBENZO-P-DIOXINS AND POLYBROMINATED DIBENZOFURANS AS IMPURITIES IN COMMERCIAL POLYBROMINATED DIPHENYL ETHER MIXTURES.

EPA Science Inventory

The objective of the present study is to determine the concentrations and compositions of polybrominated biphenyls (PBBs), polybrominated dibenzo-p-dioxins (PBDDs), and polybrominated dibenzofurans (PBDFs) as contaminants in the commercial polybrominated diphenylether (PBDE) mixt...

ENZYME-LINKED IMMUNOSORBENT ASSAY FOR SCREENING DIOXIN SOIL CONTAMINATION BY UNCONTROLLED COMBUSTION DURING INFORMAL RECYCLING IN SLUMS

PubMed Central

Trindade, Mirta; Nording, Malin; Nichkova, Mikaela; Spinnel, Erik; Haglund, Peter; Last, Michael S.; Gee, Shirley; Hammock, Bruce; Last, Jerold A.; González-Sapienza, Gualberto; Brena, Beatriz M.

2010-01-01

Uncontrolled combustion due to garbage recycling is a widespread activity among slum dwellers in distressed economy countries and has been indicated as a major source of dioxin contamination. However, because of the high cost and complexity of gas chromatography/high-resolution mass spectrometry (GC-HRMS) analysis, the magnitude of the problem remains largely unknown. The present study describes a first approach toward the use of a dioxin antibody-based enzyme-linked immunosorbent assay (ELISA) as the basis for a sustainable, simple, and low-cost monitoring program to assess the toxicological impact of uncontrolled combustion in slums. A panel of 16 samples was analyzed by GC-HRMS and ELISA on split extracts. Close to 20% of the analyzed samples showed dioxin concentrations up to almost twice the guidance level for residential soil in several countries, pointing out the need for performing a large-scale monitoring program. Despite the potential for variations in dioxin congener distribution due to the mixed nature of the incinerated material, there was a good correlation between the toxic equivalents as determined by GC-HRMS and ELISA. Furthermore, an interlaboratory ELISA validation showed that the capacity to perform the dioxin ELISA was successfully transferred between laboratories. It was concluded that the ELISA method performed very well as a screening tool to prioritize samples for instrumental analysis, which allows cutting down costs significantly. PMID:18522475

Determination of relative assay response factors for toxic chlorinated and bromiated dioxins/furans using an enyme immunoassay (EIA) and a chemically-activated luciferase gene expression cell bioassay (CALUX)

EPA Science Inventory

Determination of dioxin-like activity requires knowledge of both the concentration and toxicity to evaluate the risk of adverse human health and environmental effects. The dioxin-like response of several polybrominated dibenzo-p-dioxins/furans (PBDDs/Fs) and polybrominated/chlori...

40 CFR 63.9915 - What test methods and other procedures must I use to demonstrate initial compliance with dioxin...

Code of Federal Regulations, 2010 CFR

2010-07-01

... must I use to demonstrate initial compliance with dioxin/furan emission limits? 63.9915 Section 63.9915....9915 What test methods and other procedures must I use to demonstrate initial compliance with dioxin... limit for dioxins/furans in Table 1 to this subpart, you must follow the test methods and procedures...

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...

Update to An Inventory of Sources and Environmental Releases of Dioxin-Like Compounds in the United States for the Years 1987, 1995, and 2000 (2013, External Review Draft)

EPA Science Inventory

In 2006, EPA published an inventory of sources and environmental releases of dioxin-like compounds in the United States. This draft report presents an update and revision to that dioxin source inventory. It also presents updated estimates of environmental releases of dioxin-like...

ENDOMETRIOSIS IN A COHORT OF WOMEN LIVING IN THE KANAWHA RIVER VALLEY IN WEST VIRGINIA: BLOOD LEVELS OF NON-DIOXIN-LIKE PCBs AND RELATIONSHIP WITH BMI AND AGE

EPA Science Inventory

Industrial activities, specifically from petroleum and chemical manufacturing facilities, in the Kanawha River Valley (KRV) of West Virginia have resulted in releases of dioxin and dioxin-like chemicals (DLCs). I Most of the dioxin found in this region has resulted from the produ...

Hospitals and plastics. Dioxin prevention and medical waste incinerators.

PubMed Central

Thornton, J; McCally, M; Orris, P; Weinberg, J

1996-01-01

CHLORINATED DIOXINS and related compounds are extremely potent toxic substances, producing effects in humans and animals at extremely low doses. Because these compounds are persistent in the environment and accumulate in the food chain, they are now distributed globally, and every member of the human population is exposed to them, primarily through the food supply and mothers' milk. An emerging body of information suggests that dioxin contamination has reached a level that may pose a large-scale, long-term public health risk. Of particular concern are dioxin's effects on reproduction, development, immune system function, and carcinogenesis. Medical waste incineration is a major source of dioxins. Polyvinyl chloride (PVC) plastic, as the dominant source of organically bound chlorine in the medical waste stream, is the primary cause of "iatrogenic" dioxin produced by the incineration of medical wastes. Health professionals have a responsibility to work to reduce dioxin exposure from medical sources. Health care institutions should implement policies to reduce the use of PVC plastics, thus achieving major reductions in medically related dioxin formation. Images p298-a p299-a p300-a p301-a p305-a p307-a p310-a PMID:8711095

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.

Risk-Based Consumption Advice for Farmed Atlantic and Wild Pacific Salmon Contaminated with Dioxins and Dioxin-like Compounds

PubMed Central

Foran, Jeffery A.; Carpenter, David O.; Hamilton, M. Coreen; Knuth, Barbara A.; Schwager, Steven J.

2005-01-01

We reported recently that several organic contaminants occurred at elevated concentrations in farmed Atlantic salmon compared with concentrations of the same contaminants in wild Pacific salmon [Hites et al. Science 303:226–229 (2004)]. We also found that polychlorinated biphenyls (PCBs), toxaphene, dieldrin, dioxins, and polybrominated diphenyl ethers occurred at higher concentrations in European farm-raised salmon than in farmed salmon from North and South America. Health risks (based on a quantitative cancer risk assessment) associated with consumption of farmed salmon contaminated with PCBs, toxaphene, and dieldrin were higher than risks associated with exposure to the same contaminants in wild salmon. Here we present information on cancer and noncancer health risks of exposure to dioxins in farmed and wild salmon. The analysis is based on a tolerable intake level for dioxin-like compounds established by the World Health Organization and on risk estimates for human exposure to dioxins developed by the U.S. Environmental Protection Agency. Consumption of farmed salmon at relatively low frequencies results in elevated exposure to dioxins and dioxin-like compounds with commensurate elevation in estimates of health risk. PMID:15866762

Mortality rates among workers exposed to dioxins in the manufacture of pentachlorophenol.

PubMed

Collins, James J; Bodner, Kenneth; Aylward, Lesa L; Wilken, Michael; Swaen, Gerard; Budinsky, Robert; Rowlands, Craig; Bodnar, Catherine M

2009-10-01

We sought to determine if workers exposed to dioxins in pentachlorophenol (PCP) manufacturing were at increased risk of death from specific causes. We examined death rates among 773 workers exposed to chlorinated dioxins during PCP manufacturing from 1937 to 1980 using serum dioxin evaluations to estimate exposures to five dioxins. Deaths from all causes combined, all cancers combined, lung cancer, diabetes, and ischemic heart disease were near expected levels. There were eight deaths from non-Hodgkin lymphoma (standardized mortality ratios = 2.4, 95% CI = 1.0 to 4.8). We observed no trend of increasing risk for any cause of death with increasing dioxin exposure. However, the highest rates of non-Hodgkin lymphoma were found in the highest exposure group (standardized mortality ratios = 4.5, 95% CI = 1.2 to 11.5). Other than possibly an increased risk of non-Hodgkin lymphoma, we find no other cause of death related to the mixture of the dioxin contaminants found in PCP.

The reduction of dioxin emissions from the processes of heat and power generation.

PubMed

Wielgosiński, Grzegorz

2011-05-01

The first reports that it is possible to emit dioxins from the heat and power generation sector are from the beginning of the 1980s. Detailed research proved that the emission of dioxins might occur during combustion of hard coal, brown coal, and furnace oil as well as coke-oven gas. The emission of dioxins occurs in wood incineration; wood that is clean and understood as biomass; or, in particular, wood waste (polluted). This paper thoroughly discusses the mechanism of dioxin formation in thermal processes, first and foremost in combustion processes. The parameters influencing the quantity of dioxins formed and the dependence of their quantity on the conditions of combustion are highlighted. Furthermore, the methods of reducing dioxin emissions from combustion processes (primary and secondary) are discussed. The most efficacious methods that may find application in the heat and power generation sector are proposed; this is relevant from the point of view of the implementation of the Stockholm Convention resolutions in Poland with regard to persistent organic pollutants.

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.

Morbidity study of extruder personnel with potential exposure to brominated dioxins and furans. II. Results of clinical laboratory studies.

PubMed

Ott, M G; Zober, A

1996-12-01

To test whether dioxins affect liver and thyroid function, lipid metabolism and glucose or immunological variables, in workers exposed to brominated dioxins and furans. 34 male production employees (29 were extruder operators) and eight technical support personnel were studied, all of whom were potentially exposed to polybrominated dibenzo-p-dioxins (PBDDs) and furans (PBDFs) during production of resins containing polybrominated diphenyl ethers (PBDEs). Controls were from a similar resin producing plant that did not use PBDEs. Blood samples were analysed for tetra, penta, and hexabrominated congeners, but 2,3,7,8-TBDD was the only exposure measure used in the regression analyses. Seven liver function indicators, five measures of blood lipids and glucose, four haematology and blood coagulation measures, and three measures of thyroid function were examined. None of the variables was statistically related to concentration of 2,3,7,8-TBDD in the regression analyses. Cigarette smoking was related to several outcomes at the 0.05 level: aspartate aminotransferase, alanine aminotransferase, glutamate dehydrogenase (GLDH), erythrocyte sedimentation rate, and white blood cell count. Body mass index was also related to alanine aminotransferase, gamma-glutamyltranspeptidase, cholinesterase, GLDH, cholesterol, triglycerides, high density lipoprotein, low density lipoprotein, and glucose concentrations. No definitive associations between liver, blood lipid, thyroid, or immunological variables and exposure to brominated dioxins or blood lipid concentration of 2,3,7,8-TBDD were found. The study population was small and hence the findings must be interpreted with caution. Nevertheless, these results provide a base for interpreting the results of clinical studies in similarly exposed populations.

CHLOROBENZENES, CHLOROPHENOLS, PHAS AND LOW CHLORINATED DIOXIN/FURAN POST-BOILER TOXICITY INDICATORS IN MUNICIPAL SOLID WASTE INCINERATORS

EPA Science Inventory

Research has sought indicator compounds for fast and less costly predictive monitoring of polychlorinated dibenzo-p-dioxin and furans, PCDD/F, toxic equivalent concentrations or TEQs. Studies have shown chlorobenzenes and chlorophenols had a good correlation with TEQ, suggesting ...

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 ...

EMISSIONS OF POLYCHLORINATED DIBENZO-P-DIOXINS AND POLYCHLORINATED DIBENZOFURANS FROM THE OPEN BURNING OF HOUSEHOLD WASTE IN BARRELS

EPA Science Inventory

Backyard burning of household waste in barrels is a common waste disposal practice for which pollutant emissions have not been well characterized. This study measured the emissions of several pollutants, including polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofura...

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.

40 CFR Table 2 to Subpart Hhh of... - Toxic Equivalency Factors

Code of Federal Regulations, 2010 CFR

2010-07-01

..., Subpt. HHH, Table 2 Table 2 to Subpart HHH of Part 62—Toxic Equivalency Factors Dioxin/furan congener Toxic equivalency factor 2,3,7,8-tetrachlorinated dibenzo-p-dioxin 1 1,2,3,7,8-pentachlorinated dibenzo-p-dioxin 0.5 1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin 0.1 1,2,3,7,8,9-hexachlorinated dibenzo-p...

40 CFR Table 2 to Subpart Ttttt of... - Toxic Equivalency Factors

Code of Federal Regulations, 2010 CFR

2010-07-01

..., Subpt. TTTTT, Table 2 Table 2 to Subpart TTTTT of Part 63—Toxic Equivalency Factors Dioxin/furan congener Toxic equivalency factor 2,3,7,8-tetrachlorinated dibenzo-p-dioxin 1 1,2,3,7,8-pentachlorinated dibenzo-p-dioxin 1 1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin 0.1 1,2,3,7,8,9-hexachlorinated dibenzo-p...

2,3,7,8-Tetrachlorodibenzo-P-Dioxin (TCDD) Dose-Response Studies: Preliminary Literature Search Results and Request for Additional Studies

EPA Science Inventory

EPA invited the public to comment on the preliminary list of in vivo mammalian dose-response citations for 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD). This list was compiled as a first step in the development of EPA’s response to the National Academy of Sciences comments (NAS, 2...

Dioxins, furans and dioxin-like PCBs in human blood: causes or consequences of diabetic nephropathy?

PubMed

Everett, Charles J; Thompson, Olivia M

2014-07-01

Nephropathy, or kidney disease, is a major, potential complication of diabetes. We assessed the association of 6 chlorinated dibenzo-p-dioxins, 9 chlorinated dibenzofurans and 8 polychlorinated biphenyls (PCBs) in blood with diabetic nephropathy in the 1999-2004 National Health and Nutrition Examination Survey (unweighted N=2588, population estimate=117,658,357). Diabetes was defined as diagnosed or undiagnosed (glycohemoglobin ≥ 6.5%) and nephropathy defined as urinary albumin to creatinine ratio >30 mg/g, representing microalbuminuria or macroalbuminuria. For the 8 chemicals analyzed separately, values above the 75th percentile were considered elevated, whereas for the other 15 compounds values above the maximum limit of detection were considered elevated. Seven of 8 dioxins and dioxin-like compounds, analyzed separately, were found to be associated with diabetic nephropathy. The chemicals associated with diabetic nephropathy were: 1,2,3,6,7,8-Hexachlorodibenzo-p-dioxin; 1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin; 2,3,4,7,8-Pentachlorodibenzofuran; PCB 126; PCB 169; PCB 118; and PCB 156. Three of the 8 dioxins and dioxin-like compounds; 1,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin; 2,3,4,7,8-Pentachlorodibenzofuran and PCB 118; expressed as log-transformed continuous variables; were associated with diabetes without nephropathy. When 4 or more of the 23 chemicals were elevated the odds ratios were 7.00 (95% CI=1.80-27.20) for diabetic nephropathy and 2.13 (95% CI=0.95-4.78) for diabetes without nephropathy. Log-transformed toxic equivalency (TEQ) was associated with both diabetic nephropathy, and diabetes without nephropathy, the odds ratios were 2.35 (95% CI=1.57-3.52) for diabetic nephropathy, and 1.44 (95% CI=1.11-1.87) for diabetes without nephropathy. As the kidneys function to remove waste products from the blood, diabetic nephropathy could be either the cause or the consequence (or both) of exposure to dioxins, furans and dioxin-like PCBs. Copyright © 2014 Elsevier Inc. All rights reserved.

Dioxin Sensitivity-Related Two Critical Amino Acids of Arylhydrocarbon Receptor May Not Correlate with the Taxonomy or Phylogeny in Avian Species

PubMed Central

FUJISAWA, Nozomi; KAWAI, Yusuke K.; NAKAYAMA, Shouta M. M.; IKENAKA, Yoshinori; YAMAMOTO, Hideaki; ISHIZUKA, Mayumi

2013-01-01

ABSTRACT There are two arylhydrocarbon receptor (AhR) isoforms in birds, AhR1 and AhR2. The varying sensitivity of AhR is reported to be related to two critical amino acids at positions 325 and 381 in the AhR1 ligand-binding domain. In this study, seven avian species whose in vivo dioxin sensitivity was known, and 13 species with no data regarding their in vivo dioxin sensitivity were examined. The two critical amino acids in the ligand-binding domain were investigated in avian species, and the results were compared with the taxonomy or phylogenetic trees for the bird AhR proteins. We found that the two critical amino acids did not correlate with the taxonomy or phylogeny of these proteins, suggesting that dioxin sensitivity was independent of taxonomy. PMID:23912877

Dioxin mediates downregulation of the reduced folate carrier transport activity via the arylhydrocarbon receptor signalling pathway

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

Halwachs, Sandra, E-mail: halwachs@vetmed.uni-leipzig.d; Lakoma, Cathleen; Gebhardt, Rolf

2010-07-15

Dioxins such as 2,3,7,8-tetrachlordibenzo-p-dioxin (TCDD) are common environmental contaminants known to regulate several genes via activation of the transcription factor aryl hydrocarbon receptor (AhR) associated with the development of numerous adverse biological effects. However, comparatively little is known about the molecular mechanisms by which dioxins display their toxic effects in vertebrates. The 5' untranslated region of the hepatocellular Reduced folate carrier (Rfc1; Slc19a1) exhibits AhR binding sites termed dioxin responsive elements (DRE) that have as yet only been found in the promoter region of prototypical TCDD target genes. Rfc1 mediated transport of reduced folates and antifolate drugs such as methotrexatemore » (MTX) plays an essential role in physiological folate homeostasis and MTX cancer chemotherapy. In order to determine whether this carrier represents a target gene of dioxins we have investigated the influence of TCDD on functional Rfc1 activity in rat liver. Pre-treatment of rats with TCDD significantly diminished hepatocellular Rfc1 uptake activity in a time- and dose-dependent manner. In further mechanistic studies we demonstrated that this reduction was due to TCDD-dependent activation of the AhR signalling pathway. We additionally showed that binding of the activated receptor to DRE motifs in the Rfc1 promoter resulted in downregulation of Rfc1 gene expression and reduced carrier protein levels. As downregulation of pivotal Rfc1 activity results in functional folate deficiency associated with an elevated risk of cardiovascular diseases or carcinogenesis, our results indicate that deregulation of this essential transport pathway represents a novel regulatory mechanism how dioxins display their toxic effects through the Ah receptor.« less

Dioxin Exposure Initiative

EPA Pesticide Factsheets

The Dioxin Exposure Initiative (DEI) is no longer active. This page contains a summary of the dioxin exposure initiative with illustrations, contact and background information.Originally supported by scientist Matthew Lorber, who retired in Mar 2017.

Immuno-detection of dioxins using a recombinant protein of aryl hydrocarbon receptor (AhR) fused with sfGFP.

PubMed

Faiad, Walaa; Hanano, Abdulsamie; Kabakibi, Mohamed Maher; Abbady, Abdul Qader

2016-06-21

Dioxins are one of the most toxic groups of persistent organic pollutants. Their bioaccumulation through the food chain constitutes a potential risk for human health. Upon cell entry, dioxins bind specifically and firmly to the aryl hydrocarbon receptor (AhR), leading to the stimulation of several enzymes responsible for its detoxification. Dioxin/AhR interaction could be exploited as an affordable alternative to a variety of analytical methods for detecting dioxin contamination in the environment. In this work, the ligand binding domain (LBD) of the AhR was cloned downstream a superfolder form of the green fluorescent protein (sfGFP), resulting in the construct pRSET-sfGFP-AhR. High level of expressed sfGFP-AhR fusion protein (50 kDa) was recovered from the inclusion bodies of E. coli by simple solubilization with the Arginine, and purified by affinity chromatography via its N-terminal 6 × His tag. Its purity was confirmed by SDS-PAGE analysis and immunoblotting with anti-His or anti-GFP antibodies. Indirect ELISA revealed the ability of the sfGFP-AhR, but not the sfGFP, to bind to the immobilized dioxin with the possibility to detect such interaction by both its 6 × His and GFP tags,Competitive ELISA showed that anti-dioxin antibody was more sensitive to low dioxin concentrations than sfGFP-AhR. Nevertheless,the detection range of sfGFP-AhR fusion was much wider and the detection limit was of about 10 ppt (parts per trillion) of free dioxin in the tested artificial samples. this highly expressed and functional sfGFP-AhR fusion protein provides a promising molecular tool for detecting and quantifying different congeners of dioxins.

Third-generation Ah receptor-responsive luciferase reporter plasmids: amplification of dioxin-responsive elements dramatically increases CALUX bioassay sensitivity and responsiveness.

PubMed

He, Guochun; Tsutsumi, Tomoaki; Zhao, Bin; Baston, David S; Zhao, Jing; Heath-Pagliuso, Sharon; Denison, Michael S

2011-10-01

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD, dioxin) and related dioxin-like chemicals are widespread and persistent environmental contaminants that produce diverse toxic and biological effects through their ability to bind to and activate the Ah receptor (AhR) and AhR-dependent gene expression. The chemically activated luciferase expression (CALUX) system is an AhR-responsive recombinant luciferase reporter gene-based cell bioassay that has been used in combination with chemical extraction and cleanup methods for the relatively rapid and inexpensive detection and relative quantitation of dioxin and dioxin-like chemicals in a wide variety of sample matrices. Although the CALUX bioassay has been validated and used extensively for screening purposes, it has some limitations when screening samples with very low levels of dioxin-like chemicals or when there is only a small amount of sample matrix for analysis. Here, we describe the development of third-generation (G3) CALUX plasmids with increased numbers of dioxin-responsive elements, and stable transfection of these new plasmids into mouse hepatoma (Hepa1c1c7) cells has produced novel amplified G3 CALUX cell bioassays that respond to TCDD with a dramatically increased magnitude of luciferase induction and significantly lower minimal detection limit than existing CALUX-type cell lines. The new G3 CALUX cell lines provide a highly responsive and sensitive bioassay system for the detection and relative quantitation of very low levels of dioxin-like chemicals in sample extracts.

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.

Effect of a chemical manufacturing plant on community cancer rates

PubMed Central

Mannes, Trish; Emmett, Katy; Willmore, Alan; Churches, Tim; Sheppeard, Vicky; Kaldor, Jill

2005-01-01

Background We conducted a retrospective study to determine if potential past exposure to dioxin had resulted in increased incidence of cancer in people living near a former manufacturing plant in New South Wales, Australia. During operation, from 1928 to 1970, by-products of the manufacturing process, including dioxin and other chemical waste, were dumped into wetlands and mangroves, discharged into a nearby bay and used to reclaim land along the foreshore, leaving a legacy of significant dioxin contamination. Methods We selected 20 Census Collector Districts within 1.5 kilometres of the former manufacturing plant as the study area. We obtained data on all cases of cancer and deaths from cancer in New South Wales from 1972 to 2001. We also compared rates for some cancer types that have been associated with dioxin exposure. Based on a person's residential address at time of cancer diagnosis, or at time of death due to cancer, various geo-coding software and processes were used to determine which collector district the case or death should be attributed to. Age and sex specific population data were used to calculate standardised incidence ratios and standardised mortality ratios, to compare the study area to two comparison areas, using indirect standardisation. Results During the 30-year study period 1,106 cases of cancer and 524 deaths due to cancer were identified in the study area. This corresponds to an age-sex standardised rate of 3.2 cases per 1,000 person-years exposed and 1.6 deaths per 1,000 person-years exposed. The study area had a lower rate of cancer and deaths from cancer than the comparison areas. The case incidence and mortality due to lung and bronchus carcinomas and haematopoietic cancers did not differ significantly from the comparison areas for the study period. There was no obvious geographical trend in ratios when comparing individual collector districts to New South Wales according to distance from the potential source of dioxin exposure. Conclusion This investigation found no evidence that dioxin contamination from this site resulted in increased cancer rates in the potentially exposed population living around the former manufacturing plant. PMID:15811184

Effect of a chemical manufacturing plant on community cancer rates.

PubMed

Mannes, Trish; Emmett, Katy; Willmore, Alan; Churches, Tim; Sheppeard, Vicky; Kaldor, Jill

2005-04-05

We conducted a retrospective study to determine if potential past exposure to dioxin had resulted in increased incidence of cancer in people living near a former manufacturing plant in New South Wales, Australia. During operation, from 1928 to 1970, by-products of the manufacturing process, including dioxin and other chemical waste, were dumped into wetlands and mangroves, discharged into a nearby bay and used to reclaim land along the foreshore, leaving a legacy of significant dioxin contamination. We selected 20 Census Collector Districts within 1.5 kilometres of the former manufacturing plant as the study area. We obtained data on all cases of cancer and deaths from cancer in New South Wales from 1972 to 2001. We also compared rates for some cancer types that have been associated with dioxin exposure. Based on a person's residential address at time of cancer diagnosis, or at time of death due to cancer, various geo-coding software and processes were used to determine which collector district the case or death should be attributed to. Age and sex specific population data were used to calculate standardised incidence ratios and standardised mortality ratios, to compare the study area to two comparison areas, using indirect standardisation. During the 30-year study period 1,106 cases of cancer and 524 deaths due to cancer were identified in the study area. This corresponds to an age-sex standardised rate of 3.2 cases per 1,000 person-years exposed and 1.6 deaths per 1,000 person-years exposed. The study area had a lower rate of cancer and deaths from cancer than the comparison areas. The case incidence and mortality due to lung and bronchus carcinomas and haematopoietic cancers did not differ significantly from the comparison areas for the study period. There was no obvious geographical trend in ratios when comparing individual collector districts to New South Wales according to distance from the potential source of dioxin exposure. This investigation found no evidence that dioxin contamination from this site resulted in increased cancer rates in the potentially exposed population living around the former manufacturing plant.

Accumulation and elimination of polychlorinated dibenzo-p-dioxins and dibenzofurans in mule ducks.

PubMed

Wu, Ting-Wei; Lee, Jai-Wei; Liu, Hsueh-Yen; Lin, Wei-Hsiao; Chu, Chun-Yen; Lin, Sheng-Lun; Chang-Chien, Guo Ping; Yu, Chi

2014-11-01

In Taiwan, a food safety crisis involving a presence of high concentrations of dioxin residues in duck eggs occurred in 2004. The dioxin content in duck meat sampled from supermarkets was also reported to be substantially higher than in products from other farm animals. Despite increased awareness of the potential for contamination and exposure to dioxins, the accumulation and elimination of dioxins in ducks have not been well characterized. In the present study, mule ducks were fed capsules containing polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) for 14 days and the trial was continued for another 28 days without PCDD/Fs supplementation. Ducks were sacrificed on the 14th, 28th, and 42nd days from the beginning of administration and samples of abdominal fat, breast, and liver tissue were obtained. The concentrations of PCDD/Fs were analyzed in the samples to investigate their distribution and elimination in various duck tissues. The bioaccumulation of PCDD/Fs in ducks was found to be tissue-dependent. In the abdominal fat, the bioconcentration factor was negatively correlated with the degree of chlorination. Conversely, more chlorinated PCDD/Fs (hexa- or hepta-congeners) were associated with higher bioconcentration in the liver and breast tissue. In terms of the efficiency of PCDD/Fs elimination, the liver was found to be the fastest, followed by the breast and the abdominal fat. The clearance rate positively correlated with the degree of chlorination, as determined by comparing the apparent elimination rate constant (k) of PCDD/Fs in various tissues. Overall, lower k values observed in this study imply that mule ducks have a reduced clearance of PCDD/Fs in comparison with layer and broiler chickens. Copyright © 2014 Elsevier B.V. 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.

Multi-Tiered System of Support: Best Differentiation Practices for English Language Learners in Tier 1

ERIC Educational Resources Information Center

Izaguirre, Cecilia

2017-01-01

Purpose: This qualitative case study explored the best practices of differentiation of Tier 1 instruction within a multi-tiered system of support for English Language Learners who were predominately Spanish speaking. Theoretical Framework: The zone of proximal development theory, cognitive theory, and the affective filter hypothesis guided this…

Levels of dioxins and dioxin-like PCBs in food of animal origin in the Netherlands during the period 2001-2011.

PubMed

Adamse, Paulien; Schoss, Stefanie; Theelen, Rob M C; Hoogenboom, Ron L A P

2017-01-01

The aim of this study was to assess levels of dioxins (polychlorinated dibenzo-p-dioxins and dibenzofurans, PCDD/Fs) and dioxin-like polychlorinated biphenyls (PCBs) (DL-PCBs) in food of animal origin produced in the Netherlands, including potential trends in time. Test results from about 2500 samples of animal derived food products (beef, veal, lamb, chicken, pork, deer, milk and eggs), sampled for the National Residue Monitoring Plan from 2001-2011, were evaluated. Most samples were screened with a bioassay and, if suspected, analysed by GC-HRMS. The fraction of samples which were non-compliant with European maximum levels was rather low, being below 1% for most food products, except for lamb. Exceedance of action levels was particularly observed for lamb and beef. To obtain an insight into background levels, a randomly taken part of the samples was directly analysed by GC-HRMS. In general, only minor decreases in mean PCDD/F and DL-PCB concentrations could be observed for the period 2001-2011. This may be due to a plateauing of current background levels but also to factors like the sensitivity of the analytical method.

Chemical looping combustion: A new low-dioxin energy conversion technology.

PubMed

Hua, Xiuning; Wang, Wei

2015-06-01

Dioxin production is a worldwide concern because of its persistence and carcinogenic, teratogenic, and mutagenic effects. The pyrolysis-chemical looping combustion process of disposing solid waste is an alternative to traditional solid waste incineration developed to reduce the dioxin production. Based on the equilibrium composition of the Deacon reaction, pyrolysis gas oxidized by seven common oxygen carriers, namely, CuO, NiO, CaSO4, CoO, Fe2O3, Mn3O4, and FeTiO3, is studied and compared with the pyrolysis gas directly combusted by air. The result shows that the activity of the Deacon reaction for oxygen carriers is lower than that for air. For four typical oxygen carriers (CuO, NiO, Fe2O3, and FeTiO3), the influences of temperature, pressure, gas composition, and tar on the Deacon reaction are discussed in detail. According to these simulation results, the dioxin production in China, Europe, the United States, and Japan is predicted for solid waste disposal by the pyrolysis-chemical looping combustion process. Thermodynamic analysis results in this paper show that chemical looping combustion can reduce dioxin production in the disposal of solid waste. Copyright © 2015. Published by Elsevier B.V.

Response to Instruction in Preschool: Results of Two Randomized Studies with Children At Significant Risk of Reading Difficulties

PubMed Central

Lonigan, Christopher J.; Phillips, Beth M.

2015-01-01

Although response-to-instruction (RTI) approaches have received increased attention, few studies have evaluated the potential impacts of RTI approaches with preschool populations. This manuscript presents results of two studies examining impacts of Tier II instruction with preschool children. Participating children were identified as substantially delayed in the acquisition of early literacy skills despite exposure to high-quality, evidence-based classroom instruction. Study 1 included 93 children (M age = 58.2 months; SD = 3.62) attending 12 Title I preschools. Study 2 included 184 children (M age = 58.2 months; SD = 3.38) attending 19 Title I preschools. The majority of children were Black/African American, and about 60% were male. In both studies, eligible children were randomized to receive either 11 weeks of need-aligned, small-group instruction or just Tier I. Tier II instruction in Study 1 included variations of activities for code- and language-focused domains with prior evidence of efficacy in non-RTI contexts. Tier II instruction in Study 2 included instructional activities narrower in scope, more intensive, and delivered to smaller groups of children. Impacts of Tier II instruction in Study 1 were minimal; however, there were significant and moderate-to-large impacts in Study 2. These results identify effective Tier II instruction but indicate that the context in which children are identified may alter the nature of Tier II instruction that is required. Children identified as eligible for Tier II in an RTI framework likely require more intensive and more narrowly focused instruction than do children at general risk of later academic difficulties. PMID:26869730

The effect of cigarette prices on brand-switching in China: a longitudinal analysis of data from the ITC China Survey

PubMed Central

White, Justin S; Li, Jing; Hu, Teh-wei; Fong, Geoffrey T; Jiang, Yuan

2014-01-01

Background Recent studies have found that Chinese smokers are relatively unresponsive to cigarette prices. As the Chinese government contemplates higher tobacco taxes, it is important to understand the reasons for this low response. One possible explanation is that smokers buffer themselves from rising cigarette prices by switching to cheaper cigarette brands. Objective This study examines how cigarette prices influence consumers’ choices of cigarette brands in China. Methods This study uses panel data from the first three waves of the International Tobacco Control China Survey, drawn from six large cities in China and collected between 2006 and 2009. The study sample includes 3477 smokers who are present in at least two waves (8552 person-years). Cigarette brands are sorted by price into four tiers, using excise tax categories to determine the cut-off for each tier. The analysis relies on a conditional logit model to identify the relationship between price and brand choice. Findings Overall, 38% of smokers switched price tiers from one wave to the next. A ¥1 change in the price of cigarettes alters the tier choice of 4–7% of smokers. Restricting the sample to those who chose each given tier at baseline, a ¥1 increase in price in a given tier would decrease the share choosing that tier by 4% for Tier 1 and 1–2% for Tiers 2 and 3. Conclusions China's large price spread across cigarette brands appears to alter the brand selection of some consumers, especially smokers of cheaper brands. Tobacco pricing and tax policy can influence consumers’ incentives to switch brands. In particular, whereas ad valorem taxes in a tiered pricing system like China's encourage trading down, specific excise taxes discourage the practice. PMID:23697645

Community exposure to hazardous site remediation in rural New Zealand: an exposed-referent study of serum dioxins and health effects.

PubMed

McBride, David; Lovelock, Kirsten; Shepherd, Daniel; Dirks, Kim; Welch, David; Gray, Andrew

2016-10-01

The New Zealand Ministry of Health responded to community concern about dioxin exposure during on-site remediation of a pesticide-contaminated rural area by commissioning this exposed-referent study of serum dioxins and health in local residents. All 200 residents were eligible, with age and sex matching to demographically comparable referents. Face-to-face interviews included questions on health status, health-related quality of life (HRQOL) and perceptions about community consultation. Thirty serum samples were obtained, eligibility being based on likelihood of exposure and age. Both HRQOL and serum outcomes were analysed by the appropriate regression methods. Of 200 eligible residents, 139 (69.5%) participated, with 139 matched referents. Mapua residents had lower physical and psychological HRQOL scores, but no difference in health status. 2,3,7,8 TCDD was below the limit of detection in the majority of all serum samples, with some congeners being higher in referents. Perceptions of the communication process were equivocal. Both dioxin levels and measures of health did not differ significantly between the exposed community and controls. Implications for public health: The results suggest neither significant dioxin exposure nor community health effects. Oversight by expert panel with health expertise, allied to sound communication, may have helped the community understand the risks. © 2016 Public Health Association of Australia.

Genomic sequencing in cystic fibrosis newborn screening: what works best, two-tier predefined CFTR mutation panels or second-tier CFTR panel followed by third-tier sequencing?

PubMed

Currier, Robert J; Sciortino, Stan; Liu, Ruiling; Bishop, Tracey; Alikhani Koupaei, Rasoul; Feuchtbaum, Lisa

2017-10-01

PurposeThe purpose of this study was to model the performance of several known two-tier, predefined mutation panels and three-tier algorithms for cystic fibrosis (CF) screening utilizing the ethnically diverse California population.MethodsThe cystic fibrosis transmembrane conductance regulator (CFTR) mutations identified among the 317 CF cases in California screened between 12 August 2008 and 18 December 2012 were used to compare the expected CF detection rates for several two- and three-tier screening approaches, including the current California approach, which consists of a population-specific 40-mutation panel followed by third-tier sequencing when indicated.ResultsThe data show that the strategy of using third-tier sequencing improves CF detection following an initial elevated immunoreactive trypsinogen and detection of only one mutation on a second-tier panel.ConclusionIn a diverse population, the use of a second-tier panel followed by third-tier CFTR gene sequencing provides a better detection rate for CF, compared with the use of a second-tier approach alone, and is an effective way to minimize the referrals of CF carriers for sweat testing. Restricting screening to a second-tier testing to predefined mutation panels, even broad ones, results in some missed CF cases and demonstrates the limited utility of this approach in states that have diverse multiethnic populations.

The impact of tiered physician networks on patient choices.

PubMed

Sinaiko, Anna D; Rosenthal, Meredith B

2014-08-01

To assess whether patient choice of physician or health plan was affected by physician tier-rankings. Administrative claims and enrollment data on 171,581 nonelderly beneficiaries enrolled in Massachusetts Group Insurance Commission health plans that include a tiered physician network and who had an office visit with a tiered physician. We estimate the impact of tier-rankings on physician market share within a plan of new patients and on the percent of a physician's patients who switch to other physicians with fixed effects regression models. The effect of tiering on consumer plan choice is estimated using logistic regression and a pre-post study design. Physicians in the bottom (least-preferred) tier, particularly certain specialist physicians, had lower market share of new patient visits than physicians with higher tier-rankings. Patients whose physician was in the bottom tier were more likely to switch health plans. There was no effect of tier-ranking on patients switching away from physicians whom they have seen previously. The effect of tiering appears to be among patients who choose new physicians and at the lower end of the distribution of tiered physicians, rather than moving patients to the "best" performers. These findings suggest strong loyalty of patients to physicians more likely to be considered their personal doctor. © Health Research and Educational Trust.

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).

Dioxin uptake by Indian plant species.

PubMed

Pandey, J S; Kumar, R; Wate, S R

2008-08-01

Dioxins like various gaseous pollutants and aerosols can be scavenged by appropriate vegetative greenbelts. Based on their stomatal properties and the models for contaminant uptake, uptake of dioxin (2,3,7,8-TCDD) by three important Indian plant species, viz. Eugenia jambolana (Jamun), Azadirachta indica (Neem) and Ficus religiosa (Peepal), has been estimated. 2,3,7,8-TCDD is a contaminant with severe harmful ecological ramifications. Computations show that Ficus religiosa has highest uptake capacity. The present exercise has its utility in designing appropriate green-belts for mitigating adverse environmental and human health impacts due to dioxins. This can be an effective management option for mitigating the damages caused by dioxins.

A STUDY OF THE MASS BALANCE OF DIOXINS AND FURANS IN LACTATING COWS IN BACKGROUND CONDITIONS

EPA Science Inventory

Consumption of animal fats account for as much as 95% of the human background exposure to compounds with dioxin-like activity. Although it is generally believed that most domestic meat and dairy animals receive most of their exposure from their feed, there is limited data availa...

Levels of Polychlorinated Dibenzo-p-Dibenzofurans, and Biphenyls in Southern Mississippi Catfish and Estimation of Potential.

EPA Science Inventory

Fish consumption has been classified as one of the primary pathways of exposure to polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and biphenyls (PCBs). In this study, we evaluated tissue levels of the 17 laterally-substituted PCDD/Fs, 12 dioxin-like PCBs, and 97 non-...

PERSISTENT ABNORMALITIES IN THE RAT MAMMARY GLAND FOLLOWING GESTATIONAL AND LACTATIONAL EXPOSURE TO 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD)

EPA Science Inventory

SUMMARY

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposure during gestation has revealed reproductive anomalies in rat offspring, including inconclusive reports of stunted mammary development in females (Brown et al., 1998, Lewis et al., 2001). The current studies wer...

The effect of a three-tier formulary on antidepressant utilization and expenditures.

PubMed

Hodgkin, Dominic; Parks Thomas, Cindy; Simoni-Wastila, Linda; Ritter, Grant A; Lee, Sue

2008-06-01

Health plans in the United States are struggling to contain rapid growth in their spending on medications. They have responded by implementing multi-tiered formularies, which label certain brand medications 'non-preferred' and require higher patient copayments for those medications. This multi-tier policy relies on patients' willingness to switch medications in response to copayment differentials. The antidepressant class has certain characteristics that may pose problems for implementation of three-tier formularies, such as differences in which medication works for which patient, and high rates of medication discontinuation. To measure the effect of a three-tier formulary on antidepressant utilization and spending, including decomposing spending allocations between patient and plan. We use claims and eligibility files for a large, mature nonprofit managed care organization that started introducing its three-tier formulary on January 1, 2000, with a staggered implementation across employer groups. The sample includes 109,686 individuals who were continuously enrolled members during the study period. We use a pretest-posttest quasi-experimental design that includes a comparison group, comprising members whose employer had not adopted three-tier as of March 1, 2000. This permits some control for potentially confounding changes that could have coincided with three-tier implementation. For the antidepressants that became nonpreferred, prescriptions per enrollee decreased 11% in the three-tier group and increased 5% in the comparison group. The own-copay elasticity of demand for nonpreferred drugs can be approximated as -0.11. Difference-in-differences regression finds that the three-tier formulary slowed the growth in the probability of using antidepressants in the post-period, which was 0.3 percentage points lower than it would have been without three-tier. The three-tier formulary also increased out-of-pocket payments while reducing plan payments and total spending. The results indicate that the plan enrollees were somewhat responsive to the changed incentives, shifting away from the drugs that became nonpreferred. However, the intervention also resulted in cost-shifting from plan to enrollees, indicating some price-inelasticity. The reduction in the proportion of enrollees filling any prescriptions contrasts with results of prior studies for non-psychotropic drug classes. Limitations include the possibility of confounding changes coinciding with three-tier implementation (if they affected the two groups differentially); restriction to continuous enrollees; and lack of data on rebates the plan paid to drug manufacturers. The results of this study suggest that the impact of the three-tier formulary approach may be somewhat different for antidepressants than for some other classes. Policymakers should monitor the effects of three-tier programs on utilization in psychotropic medication classes. Future studies should seek to understand the reasons for patients' limited response to the change in incentives, perhaps using physician and/or patient surveys. Studies should also examine the effects of three-tier programs on patient adherence, quality of care, and clinical and economic outcomes.

40 CFR 721.9662 - Thieno[3,4-b]-1,4-dioxin, 2,3-dihydro- (9CI).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Thieno[3,4-b]-1,4-dioxin, 2,3-dihydro... Specific Chemical Substances § 721.9662 Thieno[3,4-b]-1,4-dioxin, 2,3-dihydro- (9CI). (a) Chemical...-b]-1,4-dioxin, 2,3-dihydro- (9CI) (PMN P-95-1825; CAS No. 126213-50-1) is subject to reporting under...

40 CFR 372.28 - Lower thresholds for chemicals of special concern.

Code of Federal Regulations, 2010 CFR

2010-07-01

...,7,8-Hexachlorodibenzofuran 39227-28-61,2,3,4,7,8-Hexachlorodibenzo-p-dioxin 57653-85-71,2,3,6,7,8-Hexachlorodibenzo-p-dioxin 19408-74-31,2,3,7,8,9-Hexachlorodibenzo-p-dioxin 35822-46-91,2,3,4,6,7,8-Heptachlorodibenzo-p-dioxin Lead Compounds 100 39001-02-01,2,3,4,6,7,8,9-Octachlorodibenzofuran 03268-87-91,2,3,4,6,7...

40 CFR Table 3 to Subpart III of... - Toxic Equivalency Factors

Code of Federal Regulations, 2011 CFR

2011-07-01

...,3,7,8-pentachlorinated dibenzo-p-dioxin 0.5 C. 1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin 0.1 D. 1.... 1,2,3,4,6,7,8-heptachlorinated dibenzo-p-dioxin 0.01 G. 0ctachlorinated dibenzo-p-dioxin 0.001 H. 2....1 O. 1,2,3,4,6,7,8-heptachlorinated dibenzofuran 0.01 P. 1,2,3,4,7,8,9-heptachlorinated dibenzofuran...

40 CFR 372.28 - Lower thresholds for chemicals of special concern.

Code of Federal Regulations, 2011 CFR

2011-07-01

...,7,8-Hexachlorodibenzofuran 39227-28-61,2,3,4,7,8-Hexachlorodibenzo-p-dioxin 57653-85-71,2,3,6,7,8-Hexachlorodibenzo-p-dioxin 19408-74-31,2,3,7,8,9-Hexachlorodibenzo-p-dioxin 35822-46-91,2,3,4,6,7,8-Heptachlorodibenzo-p-dioxin Lead Compounds 100 39001-02-01,2,3,4,6,7,8,9-Octachlorodibenzofuran 03268-87-91,2,3,4,6,7...

40 CFR Table 3 to Subpart III of... - Toxic Equivalency Factors

Code of Federal Regulations, 2010 CFR

2010-07-01

...,3,7,8-pentachlorinated dibenzo-p-dioxin 0.5 C. 1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin 0.1 D. 1.... 1,2,3,4,6,7,8-heptachlorinated dibenzo-p-dioxin 0.01 G. 0ctachlorinated dibenzo-p-dioxin 0.001 H. 2....1 O. 1,2,3,4,6,7,8-heptachlorinated dibenzofuran 0.01 P. 1,2,3,4,7,8,9-heptachlorinated dibenzofuran...

Implementation Challenges for Tier One and Tier Two School-Based Programs for Early Adolescents

ERIC Educational Resources Information Center

LaRusso, Maria D.; Donovan, Suzanne; Snow, Catherine

2016-01-01

This mixed-method study examined the implementation and the challenges to implementation for participants in randomized controlled trials of two school-based programs for early adolescents: the Tier One Word Generation (WG) program, and the Tier Two Strategic Adolescent Reading Intervention (STARI). Levels of implementation for WG and STARI varied…

Combining Tier 2 and Tier 3 Supports for Students with Disabilities in General Education Settings

ERIC Educational Resources Information Center

MacLeod, K. Sandra; Hawken, Leanne S.; O'Neill, Robert E.; Bundock, Kaitlin

2016-01-01

Secondary level or Tier 2 interventions such as the Check-in Check-out (CICO) intervention effectively reduce problem behaviors of students who are non-responsive to school-wide interventions. However, some students will not be successful with Tier 2 interventions. This study investigated the effects of adding individualized function-based support…

Effects of a Tier 3 Phonological Awareness Intervention on Preschoolers' Emergent Literacy

ERIC Educational Resources Information Center

Noe, Sean; Spencer, Trina D.; Kruse, Lydia; Goldstein, Howard

2014-01-01

This multiple baseline design study examined the effects of a Tier 3 early literacy intervention on low-income preschool children's phonological awareness (PA). Seven preschool children who did not make progress on identifying first sounds in words during a previous Tier 2 intervention participated in a more intensive Tier 3 intervention. Children…

Analytical Study on Multi-Tier 5G Heterogeneous Small Cell Networks: Coverage Performance and Energy Efficiency.

PubMed

Xiao, Zhu; Liu, Hongjing; Havyarimana, Vincent; Li, Tong; Wang, Dong

2016-11-04

In this paper, we investigate the coverage performance and energy efficiency of multi-tier heterogeneous cellular networks (HetNets) which are composed of macrocells and different types of small cells, i.e., picocells and femtocells. By virtue of stochastic geometry tools, we model the multi-tier HetNets based on a Poisson point process (PPP) and analyze the Signal to Interference Ratio (SIR) via studying the cumulative interference from pico-tier and femto-tier. We then derive the analytical expressions of coverage probabilities in order to evaluate coverage performance in different tiers and investigate how it varies with the small cells' deployment density. By taking the fairness and user experience into consideration, we propose a disjoint channel allocation scheme and derive the system channel throughput for various tiers. Further, we formulate the energy efficiency optimization problem for multi-tier HetNets in terms of throughput performance and resource allocation fairness. To solve this problem, we devise a linear programming based approach to obtain the available area of the feasible solutions. System-level simulations demonstrate that the small cells' deployment density has a significant effect on the coverage performance and energy efficiency. Simulation results also reveal that there exits an optimal small cell base station (SBS) density ratio between pico-tier and femto-tier which can be applied to maximize the energy efficiency and at the same time enhance the system performance. Our findings provide guidance for the design of multi-tier HetNets for improving the coverage performance as well as the energy efficiency.

Analytical Study on Multi-Tier 5G Heterogeneous Small Cell Networks: Coverage Performance and Energy Efficiency

PubMed Central

Xiao, Zhu; Liu, Hongjing; Havyarimana, Vincent; Li, Tong; Wang, Dong

2016-01-01

In this paper, we investigate the coverage performance and energy efficiency of multi-tier heterogeneous cellular networks (HetNets) which are composed of macrocells and different types of small cells, i.e., picocells and femtocells. By virtue of stochastic geometry tools, we model the multi-tier HetNets based on a Poisson point process (PPP) and analyze the Signal to Interference Ratio (SIR) via studying the cumulative interference from pico-tier and femto-tier. We then derive the analytical expressions of coverage probabilities in order to evaluate coverage performance in different tiers and investigate how it varies with the small cells’ deployment density. By taking the fairness and user experience into consideration, we propose a disjoint channel allocation scheme and derive the system channel throughput for various tiers. Further, we formulate the energy efficiency optimization problem for multi-tier HetNets in terms of throughput performance and resource allocation fairness. To solve this problem, we devise a linear programming based approach to obtain the available area of the feasible solutions. System-level simulations demonstrate that the small cells’ deployment density has a significant effect on the coverage performance and energy efficiency. Simulation results also reveal that there exits an optimal small cell base station (SBS) density ratio between pico-tier and femto-tier which can be applied to maximize the energy efficiency and at the same time enhance the system performance. Our findings provide guidance for the design of multi-tier HetNets for improving the coverage performance as well as the energy efficiency. PMID:27827917

The Need and Potential of Biosensors to Detect Dioxins and Dioxin-Like Polychlorinated Biphenyls along the Milk, Eggs and Meat Food Chain

PubMed Central

Chobtang, Jeerasak; de Boer, Imke J. M.; Hoogenboom, Ron L. A. P.; Haasnoot, Willem; Kijlstra, Aize; Meerburg, Bastiaan G.

2011-01-01

Dioxins and dioxin-like polychlorinated biphenyls (DL-PCBs) are hazardous toxic, ubiquitous and persistent chemical compounds, which can enter the food chain and accumulate up to higher trophic levels. Their determination requires sophisticated methods, expensive facilities and instruments, well-trained personnel and expensive chemical reagents. Ideally, real-time monitoring using rapid detection methods should be applied to detect possible contamination along the food chain in order to prevent human exposure. Sensor technology may be promising in this respect. This review gives the state of the art for detecting possible contamination with dioxins and DL-PCBs along the food chain of animal-source foods. The main detection methods applied (i.e., high resolution gas-chromatography combined with high resolution mass-spectrometry (HRGC/HRMS) and the chemical activated luciferase gene expression method (CALUX bioassay)), each have their limitations. Biosensors for detecting dioxins and related compounds, although still under development, show potential to overcome these limitations. Immunosensors and biomimetic-based biosensors potentially offer increased selectivity and sensitivity for dioxin and DL-PCB detection, while whole cell-based biosensors present interpretable biological results. The main shortcoming of current biosensors, however, is their detection level: this may be insufficient as limits for dioxins and DL-PCBs for food and feedstuffs are in pg per gram level. In addition, these contaminants are normally present in fat, a difficult matrix for biosensor detection. Therefore, simple and efficient extraction and clean-up procedures are required which may enable biosensors to detect dioxins and DL-PCBs contamination along the food chain. PMID:22247688

The need and potential of biosensors to detect dioxins and dioxin-like polychlorinated biphenyls along the milk, eggs and meat food chain.

PubMed

Chobtang, Jeerasak; de Boer, Imke J M; Hoogenboom, Ron L A P; Haasnoot, Willem; Kijlstra, Aize; Meerburg, Bastiaan G

2011-01-01

Dioxins and dioxin-like polychlorinated biphenyls (DL-PCBs) are hazardous toxic, ubiquitous and persistent chemical compounds, which can enter the food chain and accumulate up to higher trophic levels. Their determination requires sophisticated methods, expensive facilities and instruments, well-trained personnel and expensive chemical reagents. Ideally, real-time monitoring using rapid detection methods should be applied to detect possible contamination along the food chain in order to prevent human exposure. Sensor technology may be promising in this respect. This review gives the state of the art for detecting possible contamination with dioxins and DL-PCBs along the food chain of animal-source foods. The main detection methods applied (i.e., high resolution gas-chromatography combined with high resolution mass-spectrometry (HRGC/HRMS) and the chemical activated luciferase gene expression method (CALUX bioassay)), each have their limitations. Biosensors for detecting dioxins and related compounds, although still under development, show potential to overcome these limitations. Immunosensors and biomimetic-based biosensors potentially offer increased selectivity and sensitivity for dioxin and DL-PCB detection, while whole cell-based biosensors present interpretable biological results. The main shortcoming of current biosensors, however, is their detection level: this may be insufficient as limits for dioxins and DL-PCBs for food and feedstuffs are in pg per gram level. In addition, these contaminants are normally present in fat, a difficult matrix for biosensor detection. Therefore, simple and efficient extraction and clean-up procedures are required which may enable biosensors to detect dioxins and DL-PCBs contamination along the food chain.

Change in decay rates of dioxin-like compounds in Yusho patients.

PubMed

Matsumoto, Shinya; Akahane, Manabu; Kanagawa, Yoshiyuki; Kajiwara, Jumboku; Mitoma, Chikage; Uchi, Hiroshi; Furue, Masutaka; Imamura, Tomoaki

2016-09-07

Once ingested, dioxins and dioxin-like compounds are excreted extremely slowly. Excretion can be evaluated by its half-life. Half-lives estimated from observed concentrations are affected by excretion and ongoing exposure. We investigated the change in apparent half-life using a theoretical model based on exposure to dioxin and dioxin-like compounds. We carried out longitudinal measurements of the blood concentration of dioxins and dioxin-like compounds in a Yusho cohort during 2002 to 2010. We estimated the change in decay rates of 2,3,4,7,8-PeCDF and octachlorodibenzodioxin (OCDD) using a second-order equation. We found that the decay rate of OCDD increased, whereas the decay rate of 2,3,4,7,8-PeCDF of patients with a relatively high concentration of 2,3,4,7,8-PeCDF decreased. OCDD results were in accordance with decreasing levels of dioxin and dioxin-like compounds in the environment. The decay rate of OCDD in the body was affected by the decay rate of OCDD in the environment by ingestion because it was near the steady-state. In contrast, the decay rate of 2,3,4,7,8-PeCDF in the body was affected less by ingestion from the environment because it was far higher than in the steady-state. We demonstrated that the level of 2,3,4,7,8-PeCDF in the environment is decreasing. The excretion half-life is longer than the environmental half-life, thus the excretion half-life in a Yusho patient is increased.

Third-Generation Ah Receptor–Responsive Luciferase Reporter Plasmids: Amplification of Dioxin-Responsive Elements Dramatically Increases CALUX Bioassay Sensitivity and Responsiveness

PubMed Central

He, Guochun; Tsutsumi, Tomoaki; Zhao, Bin; Baston, David S.; Zhao, Jing; Heath-Pagliuso, Sharon; Denison, Michael S.

2011-01-01

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD, dioxin) and related dioxin-like chemicals are widespread and persistent environmental contaminants that produce diverse toxic and biological effects through their ability to bind to and activate the Ah receptor (AhR) and AhR-dependent gene expression. The chemically activated luciferase expression (CALUX) system is an AhR-responsive recombinant luciferase reporter gene–based cell bioassay that has been used in combination with chemical extraction and cleanup methods for the relatively rapid and inexpensive detection and relative quantitation of dioxin and dioxin-like chemicals in a wide variety of sample matrices. Although the CALUX bioassay has been validated and used extensively for screening purposes, it has some limitations when screening samples with very low levels of dioxin-like chemicals or when there is only a small amount of sample matrix for analysis. Here, we describe the development of third-generation (G3) CALUX plasmids with increased numbers of dioxin-responsive elements, and stable transfection of these new plasmids into mouse hepatoma (Hepa1c1c7) cells has produced novel amplified G3 CALUX cell bioassays that respond to TCDD with a dramatically increased magnitude of luciferase induction and significantly lower minimal detection limit than existing CALUX-type cell lines. The new G3 CALUX cell lines provide a highly responsive and sensitive bioassay system for the detection and relative quantitation of very low levels of dioxin-like chemicals in sample extracts. PMID:21775728

Morbidity study of extruder personnel with potential exposure to brominated dioxins and furans. II. Results of clinical laboratory studies.

PubMed Central

Ott, M G; Zober, A

1996-01-01

OBJECTIVE: To test whether dioxins affect liver and thyroid function, lipid metabolism and glucose or immunological variables, in workers exposed to brominated dioxins and furans. METHODS: 34 male production employees (29 were extruder operators) and eight technical support personnel were studied, all of whom were potentially exposed to polybrominated dibenzo-p-dioxins (PBDDs) and furans (PBDFs) during production of resins containing polybrominated diphenyl ethers (PBDEs). Controls were from a similar resin producing plant that did not use PBDEs. Blood samples were analysed for tetra, penta, and hexabrominated congeners, but 2,3,7,8-TBDD was the only exposure measure used in the regression analyses. Seven liver function indicators, five measures of blood lipids and glucose, four haematology and blood coagulation measures, and three measures of thyroid function were examined. RESULTS: None of the variables was statistically related to concentration of 2,3,7,8-TBDD in the regression analyses. Cigarette smoking was related to several outcomes at the 0.05 level: aspartate aminotransferase, alanine aminotransferase, glutamate dehydrogenase (GLDH), erythrocyte sedimentation rate, and white blood cell count. Body mass index was also related to alanine aminotransferase, gamma-glutamyltranspeptidase, cholinesterase, GLDH, cholesterol, triglycerides, high density lipoprotein, low density lipoprotein, and glucose concentrations. No definitive associations between liver, blood lipid, thyroid, or immunological variables and exposure to brominated dioxins or blood lipid concentration of 2,3,7,8-TBDD were found. CONCLUSIONS: The study population was small and hence the findings must be interpreted with caution. Nevertheless, these results provide a base for interpreting the results of clinical studies in similarly exposed populations. PMID:8994404

BIOLOGICALLY-BASED RAPID SCREENING METHODS FOR DIOXINS IN THE UNITED STATES

EPA Science Inventory

Because of the extensive cost, in personnel, time, equipment, and money to measure dioxin-like chemicals analytically, alternative technologies have been developed to measure the integrated sum of the activity of the dioxin-like chemicals.

Regulatory Compliance in Multi-Tier Supplier Networks

NASA Technical Reports Server (NTRS)

Goossen, Emray R.; Buster, Duke A.

2014-01-01

Over the years, avionics systems have increased in complexity to the point where 1st tier suppliers to an aircraft OEM find it financially beneficial to outsource designs of subsystems to 2nd tier and at times to 3rd tier suppliers. Combined with challenging schedule and budgetary pressures, the environment in which safety-critical systems are being developed introduces new hurdles for regulatory agencies and industry. This new environment of both complex systems and tiered development has raised concerns in the ability of the designers to ensure safety considerations are fully addressed throughout the tier levels. This has also raised questions about the sufficiency of current regulatory guidance to ensure: proper flow down of safety awareness, avionics application understanding at the lower tiers, OEM and 1st tier oversight practices, and capabilities of lower tier suppliers. Therefore, NASA established a research project to address Regulatory Compliance in a Multi-tier Supplier Network. This research was divided into three major study efforts: 1. Describe Modern Multi-tier Avionics Development 2. Identify Current Issues in Achieving Safety and Regulatory Compliance 3. Short-term/Long-term Recommendations Toward Higher Assurance Confidence This report presents our findings of the risks, weaknesses, and our recommendations. It also includes a collection of industry-identified risks, an assessment of guideline weaknesses related to multi-tier development of complex avionics systems, and a postulation of potential modifications to guidelines to close the identified risks and weaknesses.

Dioxin induces expression of hsa-miR-146b-5p in human neuroblastoma cells.

PubMed

Xu, Tuan; Xie, Heidi Q; Li, Yunping; Xia, Yingjie; Sha, Rui; Wang, Lingyun; Chen, Yangsheng; Xu, Li; Zhao, Bin

2018-01-01

Dioxin can cause a series of neural toxicological effects. MicroRNAs (miRs) play important roles in regulating nervous system function and mediating cellular responses to environmental pollutants, such as dioxin. Hsa-miR-146b-5p appears to be involved in neurodegenerative diseases and brain tumors. However, little is known about effects of dioxin on the expression of hsa-miR-146b-5p. We found that the hsa-miR-146b-5p expression and its promoter activity were significantly increased in dioxin treated SK-N-SH cells, a human-derived neuroblastoma cell line. Potential roles of hsa-miR-146b-5p in mediating neural toxicological effects of dioxin may be due to the regulation of certain target genes. We further confirmed that hsa-miR-146b-5p significantly suppressed acetylcholinesterase (AChE) activity and targeted the 3'-untranslated region of the AChE T subunit, which has been down-regulated in dioxin treated SK-N-SH cells. Functional bioinformatic analysis showed that the known and predicted target genes of hsa-miR-146b-5p were involved in some brain functions or cyto-toxicities related to known dioxin effects, including synapse transmission, in which AChE may serve as a responsive gene for mediating the effect. Copyright © 2017. Published by Elsevier B.V.

New perspectives for multi-level regulations of neuronal acetylcholinesterase by dioxins.

PubMed

Xie, Heidi Q; Xu, Tuan; Chen, Yangsheng; Li, Yunping; Xia, Yingjie; Xu, Sherry L; Wang, Lingyun; Tsim, Karl W K; Zhao, Bin

2016-11-25

Acetylcholinesterase (AChE; EC 3.1.1.7) is a vital functional enzyme in cholinergic neurotransmission which can rapidly hydrolyze neurotransmitter, acetylcholine, in the central and peripheral nervous systems. Emerging evidence showed that in addition to classical environmental AChE inhibitors, e.g. organophosphate and carbamate pesticides, dioxins are a new type of xenobiotic causing impairment of AChE. Dioxin can transcriptionally or post-transcriptionally suppress AChE expression in human neuroblastoma cells or mouse immune cells via the aryl hydrocarbon receptor (AhR) pathway, respectively. Dioxins can affect gene expression through other mechanisms, such as cross-talk with other signaling cascades and epigenetic modulations. Therefore, in this review, by summarizing the known mechanisms of AChE regulation and dioxin-induced gene alteration, potential signaling cascades and epigenetic mechanisms are proposed for dioxin-mediated AChE regulation. Mitogen activated protein (MAP) kinase, 3', 5'-cyclic adenosine monophosphate (cAMP) and calcium-related singaling pathways, as well as potential epigenetic mechanisms, such as DNA methylation, and post-transcriptional regulation via microRNAs, including hsa-miR-132, hsa-miR-212 and hsa-miR-25-3p are discussed here. These proposed mechanisms may be invaluable not only to promote comprehensive understanding of the action mechanisms for dioxin, but to illustrate the molecular basis of dioxin-induced health impacts. Copyright © 2016 Elsevier Ireland 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.

Documents for Recommended Toxicity Equivalency Factors for Human Health Risk Assessments of Dioxin and Dioxin-Like Compounds

EPA Pesticide Factsheets

This document describes the U.S. Environmental Protection Agency’s (U.S. EPA’s) updated approach for evaluating the human health risks from exposures to environmental media containing dioxin-like compounds (DLCs).

2009 DIOXIN RE-ASSESSMENT WORKSHOP

EPA Science Inventory

EPA announced a

Scientific Workshop To Inform EPA's Response to
National Academy of Science Comments on the Health
Effects of Dioxin in EPA's 2003 Dioxin Reassessment
Hilton Cincinnati Netherland Plaza, Cincinnati, OH
Held: February 1...

Dietary exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans via fish consumption and dioxin-like activity in fish determined by H4IIE-luc bioassay.

PubMed

Chan, Janet Kit Yan; Man, Yu Bon; Xing, Guan Hua; Wu, Sheng Chun; Murphy, Margaret B; Xu, Ying; Wong, Ming H

2013-10-01

Dietary exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) via fish consumption in two major electronic (e) waste sites: Guiyu (GY), Guangdong Province and Taizhou (TZ), Zhejiang Province, and dioxin-like activity in fish determined by H4IIE-luc bioassay. In the present study, all fish were below EU's maximum allowable concentration in muscle of fish (4 pg WHO-TEQ/g wet wt), except crucian (4.28 pg WHO-TEQ/g wet wt) and silver carps (7.49 pg WHO-TEQ/g wet wt) collected from GY rivers. Moreover, the residual concentration in bighead carp collected from GY (2.15 pg WHO-TEQ/g wet wt) was close to the EU's action level (3 pg WHO-TEQ/g wet wt) which gives "early warning" to the competent authorities and operators to take measures to eliminate contamination. In addition, results indicated that the maximum human intake of PCDD/Fs via freshwater fish consumption in GY was 4.31 pg WHO-TEQ/kg bw/day, which exceeds the higher end of the tolerable daily intake recommended by the WHO, EC-SCF and JECFA (1-4, 2 and 2.3 pg WHO-TEQ/kg bw/day respectively). Furthermore, H4IIE-luc cell bioassay provides a very sensitive and cost-efficient screening tool for assessing the overall dioxin-like toxicity in the study, and is therefore valuable for high-throughput environmental monitoring studies. Copyright © 2012 Elsevier B.V. All rights reserved.

Liver tumor promotion by 2,3,7,8-tetrachlorodibenzo-p-dioxin is dependent on the aryl hydrocarbon receptor and TNF/IL-1 receptors.

PubMed

Kennedy, Gregory D; Nukaya, Manabu; Moran, Susan M; Glover, Edward; Weinberg, Samuel; Balbo, Silvia; Hecht, Stephen S; Pitot, Henry C; Drinkwater, Norman R; Bradfield, Christopher A

2014-07-01

We set out to better understand the signal transduction pathways that mediate liver tumor promotion by 2,3,7,8-tetrachlorodibenzo-p-dioxn ("dioxin"). To this end, we first employed congenic mice homozygous for either the Ahr(b1) or Ahr(d) alleles (encoding an aryl hydrocarbon receptor (AHR) with high or low binding affinity for dioxin, respectively) and demonstrated that hepatocellular tumor promotion in response to dioxin segregated with the Ahr locus. Once we had genetic evidence for the importance of AHR signaling, we then asked if tumor promotion by dioxin was influenced by "interleukin-1 (IL-1)-like" inflammatory cytokines. The importance of this question arose from our earlier observation that aspects of the acute hepatocellular toxicity of dioxin are dependent upon IL1-like cytokine signaling. To address this issue, we employed a triple knock-out (TKO) mouse model with null alleles at the loci encoding the three relevant receptors for tumor necrosis factors α and β and IL-1α and IL-1β (i.e., null alleles at the Tnfrsf1a, Tnfrsf1b, and Il-1r1 loci). The observation that TKO mice were resistant to the tumor promoting effects of dioxin in liver suggests that inflammatory cytokines play an important step in dioxin mediated liver tumor promotion in the mouse. Collectively, these data support the idea that the mechanism of dioxin acute hepatotoxicity and its activity as a promoter in a mouse two stage liver cancer model may be similar, i.e., tumor promotion by dioxin, like acute hepatotoxicity, are mediated by the linked action of two receptor systems, the AHR and the receptors for the "IL-1-like" cytokines. Published by Oxford University Press on behalf of Nucleic Acids Research 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Mass loading and partitioning of dioxins in irrigation runoff from Japanese paddy fields: combination usage of the CALUX assay with HRGC/HRMS.

PubMed

Kanematsu, Masakazu; Shimizu, Yoshihisa; Sato, Keisuke; Kim, Suejin; Suzuki, Tasuma; Park, Baeksoo; Saino, Reiko; Nakamura, Masafumi

2009-08-01

Lack of understanding of dioxins mass loading into the aquatic environment motivated the quantitative investigation of dioxins runoff from paddy fields during one entire irrigation period in the Minakuchi region, Japan. Combination use of the chemically activated luciferase gene expression (CALUX) bioassay together with high resolution gas chromatography and high resolution mass spectrometry (HRGC/HRMS) enabled efficient investigation of dioxins contamination. The result shows that the congener profile in irrigation runoff is quite similar to those in paddy soil samples and that 1,3,6,8-/1,3,7,9-TeCDD and OCDD derived from pesticides (i.e., pentachlorophenol (PCP) and chloronitrophen (CNP)) are predominant congeners in irrigation runoff. Although it is not surprising that dioxins concentration was strongly dependent on the suspended solids (SS) and the particulate organic carbon (POC) concentration, the dioxins toxic equivalency (TEQ) concentration was extremely high in irrigation runoff (max: 16,380 pg/L, corresponding to 12 pg WHO-TEQ/L) due to runoff of highly contaminated paddy soils. The results imply that dioxins concentration in a river must be monitored considering soil contamination level, land use, and soil runoff events. Using experimental data and a theoretical model, the mass loading of dioxins from the paddy fields by irrigation runoff was estimated to be 1.50 x 10(-2)% of total amount of dioxins accumulated in the paddy fields. Given the results of other researches, it is implied the following: 1) large portion of paddy soils released into the river appear to be settled on the riverbed due to small water flux, and, then, washed out and transported by rainfall runoff after irrigation period, 2) rainfall runoff itself also wash out paddy soils directly from paddy fields. Combination use of the CALUX bioassay with HRGC/HRMS is demonstrated as an alternative strategy to assess dioxins contamination in the environment.

EFFECTS OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD) ON FETAL MOUSE URINARY TRACT EPITHELIUM IN VITRO

EPA Science Inventory

2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), produces hydronephrosis by altering the differentiation and proliferation of ureteric epithelial cells in the embryonic C57BL/6N mouse urinary tract. This study examines the effects of TCDD on late gestation fetal urinary tract cells u...

A comparison of Tier 1 and Tier 3 medical homes under Oklahoma Medicaid program.

PubMed

Kumar, Jay I; Anthony, Melody; Crawford, Steven A; Arky, Ronald A; Bitton, Asaf; Splinter, Garth L

2014-04-01

The patient-centered medical home (PCMH) is a team-based model of care that seeks to improve quality of care and control costs. The Oklahoma Health Care Authority (OHCA) directs Oklahoma's Medicaid program and contracts with 861 medical home practices across the state in one of three tiers of operational capacity: Tier 1 (Basic), Tier 2 (Advanced) and Tier 3 (Optimal). Only 13.5% (n = 116) homes are at the optimal level; the majority (59%, n = 508) at the basic level. In this study, we sought to determine the barriers that prevented Tier 1 homes from advancing to Tier 3 level and the incentives that would motivate providers to advance from Tier 1 to 3. Our hypotheses were that Tier 1 medical homes were located in smaller practices with limited resources and the providers are not convinced that the expense of advancing from Tier 1 status to Tier 3 status was worth the added value. We analyzed OHCA records to compare the 508 Tier 1 (entry-level) with 116 Tier 3 (optimal) medical homes for demographic differences with regards to location: urban or rural, duration as medical home, percentage of contracts that were group contracts, number of providers per group contract, panel age range, panel size, and member-provider ratio. We surveyed all 508 Tier 1 homes with a mail-in survey, and with focused follow up visits to identify the barriers to, and incentives for, upgrading from Tier 1 to Tier 2 or 3. We found that Tier 1 homes were more likely to be in rural areas, run by solo practitioners, serve exclusively adult panels, have smaller panel sizes, and have higher member-to-provider ratios in comparison with Tier 3 homes. Our survey had a 35% response rate. Results showed that the most difficult changes for Tier 1 homes to implement were providing 4 hours of after-hours care and a dedicated program for mental illness and substance abuse. The results also showed that the most compelling incentives for encouraging Tier 1 homes to upgrade their tier status were less"red tape"with prior authorizations, higher pay, and help with panel member follow-up. Multiple interventions may help medical homes in Oklahoma advance from the basic to the optimal level such as sharing of resources among nearby practices, expansion of OHCA online resources to help with preauthorizations and patient follow up, and the generation and transmission of data on the benefits of medical homes.

HEALTH CONSEQUENCES OF DIOXIN EXPOSURE

EPA Science Inventory

Abstract TCDD is often called the most toxic man-made chemical because of its potency to cause health effects in a wide variety of vertebrates. Structurally related persistent compounds, known as 'dioxins', have the same plethora of responses. Dioxins have effects in mu...

U.S. EPA's National Dioxin Air Monitoring Network: Analytical Issues

EPA Science Inventory

The U.S. EPA has established a National Dioxin Air Monitoring Network (NDAMN) to determine the temporal and geographical variability of atmospheric chlorinated dibenzo-p-dioxins (CDDs), furans (CDFs), and coplanar polychlorinated biphenyls (PCBs) at rural and non-impacted locatio...

National surveillance of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins/furans in soil in Taiwan.

PubMed

Hsu, Yi-Chyun; Que, Danielle E; Gou, Yan-You; Tsou, Tsui-Chun; Liu, Chung-Kun; Wang, Yen-Ling; Hou, Wen-Che; Lin, Yi-Hsien; Liu, Wen-Yao; Chao, How-Ran; Lee, Wen-Jhy

2018-07-01

In this study, the polychlorinated dibenzo-p-dioxin/furan (PCDD/F) levels in 381 soil samples coming from different background areas (n = 238) and contaminated areas (n = 143) in Taiwan were investigated from 2011 to 2015 using high resolution gas chromatograph/high resolution mass spectrometry (HRGC/HRMS). The contaminated areas showed higher PCDD/F contamination as compared to the background areas (1230 vs 749 pg/g dry weight (dw)); 14.0 vs 6.25 pg WHO 2005 -TEQ/g dw). The lowest levels were recorded in the outlying islands (1.28 pg WHO 2005 -TEQ/g dw). PCDD/F congener distribution profiles in the background and contaminated areas as well as on the islands varied. OCDD was the dominant congener in almost all locations, including the northern background (87.7%) and central contaminated (74.2%) areas. Other dominant species included OCDF and 1,2,3,4,6,7,8-HpCDD. Levels of PCDD/F-TEQs in Taiwanese soils, including the background areas, were higher than in some developing countries and regions with global background levels due to high industrialization except for the contaminated areas. Geographic differences in dioxin-contaminated soils were also shown in this study. Higher soil dioxin-TEQs were observed in locations with high populations and population densities. Despite the limitations, the economic status of Taiwan represented by the annual averaged family income (AAFI) was positively correlated to soil dioxin-TEQs. Copyright © 2018. Published by Elsevier Ltd.

Accelerating chronically unresponsive children to tier 3 instruction: what level of data is necessary to ensure selection accuracy?

PubMed

Compton, Donald L; Gilbert, Jennifer K; Jenkins, Joseph R; Fuchs, Douglas; Fuchs, Lynn S; Cho, Eunsoo; Barquero, Laura A; Bouton, Bobette

2012-01-01

Response-to-intervention (RTI) approaches to disability identification are meant to put an end to the so-called wait-to-fail requirement associated with IQ discrepancy. However, in an unfortunate irony, there is a group of children who wait to fail in RTI frameworks. That is, they must fail both general classroom instruction (Tier 1) and small-group intervention (Tier 2) before becoming eligible for the most intensive intervention (Tier 3). The purpose of this article was to determine how to predict accurately which at-risk children will be unresponsive to Tiers 1 and 2, thereby allowing unresponsive children to move directly from Tier 1 to Tier 3. As part of an efficacy study of a multitier RTI approach to prevention and identification of reading disabilities (RD), 129 first-grade children who were unresponsive to classroom reading instruction were randomly assigned to 14 weeks of small-group, Tier 2 intervention. Nonresponders to this instruction (n = 33) were identified using local norms on first-grade word identification fluency growth linked to a distal outcome of RD at the end of second grade. Logistic regression models were used to predict membership in responder and nonresponder groups. Predictors were entered as blocks of data from least to most difficult to obtain: universal screening data, Tier 1 response data, norm referenced tests, and Tier 2 response data. Tier 2 response data were not necessary to classify students as responders and nonresponders to Tier 2 instruction, suggesting that some children can be accurately identified as eligible for Tier 3 intervention using only Tier 1 data, thereby avoiding prolonged periods of failure to instruction.

Assessment of dioxin-like activity in ambient air particulate matter using recombinant yeast assays

NASA Astrophysics Data System (ADS)

Olivares, Alba; van Drooge, Barend L.; Pérez Ballesta, Pascual; Grimalt, Joan O.; Piña, Benjamin

2011-01-01

Ectopic activation of the aryl hydrocarbon receptor (AhR), also known as dioxin-like activity, is a major component of the toxicity associated with polycyclic aromatic hydrocarbons (PAH). Filtration of ambient air particulate matter through PM 10 filters followed by chemical determination of PAH concentrations and a yeast-based bioassay (RYA) were combined to evaluate and characterize dioxin-like activity in ambient air. Samples were collected in a semirural area of Northern Italy between September 2008 and February 2009. Total PAH contents ranged between 0.3 ng m -3 and 34 ng m -3 and were in correlation with seasonal variations of meteorological conditions and combustion processes. Dioxin-like activity values in air samples showed an excellent correlation (0.71 < R2 < 0.86) with the observed PAH concentrations and the predicted toxicity equivalents for PAH. This RYA-bioassay reported in the present study provides a simple and low-cost routine control for toxic PAH emissions, even at background air concentration levels.

Suppression of chlorinated aromatics by nitrogen and sulphur inhibitors in iron ore sintering.

PubMed

Zhang, Yadi; Buekens, Alfons; Liu, Lina; Zhang, Yibo; Zeng, Xiaolan; Sun, Yifei

2016-07-01

Dioxins generated by iron and steel industry account for the majority of industrial dioxins emissions. This study compares the performance of different additives (including calcium sulphate dehydrate CaSO4·2H2O; calcium polysulphide CaSx; ammonium sulphate (NH4)2SO4; 4-methylthiosemicarbazide H3C-SC(NH)2NH2 and thiourea H2NCSNH2) as suppressant of chlorinated aromatics in iron ore sintering. The formation of chlorobenzenes (CBz) and polychlorinated biphenyls (PCBs), used as surrogates for dioxins, was suppressed significantly in the present of various inhibitors (1 wt%) except for CaSO4·2H2O. Moreover, a larger molar ratio of (S + N)/Cl leads to a higher suppression efficiency, so that the inhibition capacity of (NH4)2SO4 on both CBz and PCBs was weaker than H2NCSNH2. The generation of dioxin-like PCBs (Co- or dl-PCB) was also analysed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Liver Tumor Promotion by 2,3,7,8-Tetrachlorodibenzo-p-dioxin Is Dependent on the Aryl Hydrocarbon Receptor and TNF/IL-1 Receptors

PubMed Central

Kennedy, Gregory D.; Nukaya, Manabu; Moran, Susan M.; Glover, Edward; Weinberg, Samuel; Balbo, Silvia; Hecht, Stephen S.; Pitot, Henry C.; Drinkwater, Norman R.; Bradfield, Christopher A.

2014-01-01

We set out to better understand the signal transduction pathways that mediate liver tumor promotion by 2,3,7,8-tetrachlorodibenzo-p-dioxn (“dioxin”). To this end, we first employed congenic mice homozygous for either the Ahrb1 or Ahrd alleles (encoding an aryl hydrocarbon receptor (AHR) with high or low binding affinity for dioxin, respectively) and demonstrated that hepatocellular tumor promotion in response to dioxin segregated with the Ahr locus. Once we had genetic evidence for the importance of AHR signaling, we then asked if tumor promotion by dioxin was influenced by “interleukin-1 (IL-1)-like” inflammatory cytokines. The importance of this question arose from our earlier observation that aspects of the acute hepatocellular toxicity of dioxin are dependent upon IL1-like cytokine signaling. To address this issue, we employed a triple knock-out (TKO) mouse model with null alleles at the loci encoding the three relevant receptors for tumor necrosis factors α and β and IL-1α and IL-1β (i.e., null alleles at the Tnfrsf1a, Tnfrsf1b, and Il-1r1 loci). The observation that TKO mice were resistant to the tumor promoting effects of dioxin in liver suggests that inflammatory cytokines play an important step in dioxin mediated liver tumor promotion in the mouse. Collectively, these data support the idea that the mechanism of dioxin acute hepatotoxicity and its activity as a promoter in a mouse two stage liver cancer model may be similar, i.e., tumor promotion by dioxin, like acute hepatotoxicity, are mediated by the linked action of two receptor systems, the AHR and the receptors for the “IL-1-like” cytokines. PMID:24718703

Instrumental and bioanalytical measures of dioxin-like compounds and activities in sediments of the Pohang Area, Korea.

PubMed

Hong, Seongjin; Khim, Jong Seong; Park, Jinsoon; Kim, Sunmi; Lee, Sangwoo; Choi, Kyungho; Kim, Chul-Su; Choi, Sung-Deuk; Park, Jeongim; Ryu, Jongseong; Jones, Paul D; Giesy, John P

2014-02-01

Pohang is a mid-sized city in which Korea's largest manufacturer of steel is located. The Hyeongsan River, which runs through Pohang and empties into Yeongil Bay, is therefore expected to be affected by various municipal and industrial inputs. In order to characterize aryl hydrocarbon receptor (AhR)-mediated activities in sediments from the Pohang area, a total of eight locations along the Hyeongsan River were chosen and 16 sediment samples were collected during two sampling campaigns in 2010. Organic extracts of sediments were characterized by both quantitative chemical analyses of dioxin-like chemicals and the in vitro H4IIE-luc bioassay. Significant dioxin-like activities were observed in sediments from industrial and municipal areas, which indicates that most of the dioxin-like chemicals were associated with surrounding anthropogenic sources. In general, responses of the H4IIE-luc assay were significantly correlated with concentrations of target compounds including dioxins, furans, co-planar PCBs, and dioxin-like PAHs. A potency balance analysis indicated that instrumentally derived TCDD equivalents (TEQs) explained about 77% of the bioassay-derived TCDD equivalents (TCDD-EQs). Among the target chemicals measured, certain penta-chlorinated dioxin and furan compounds accounted for the majority of dioxin-like activities associated with sediments. Compositional analysis of target chemicals the sources of such dioxin-like activities were mainly derived from the local activities such as the iron and steel industries. Concentrations and activities of AhR agonists were similar to what was measured approximately 10 years ago. Thus, while AhR agonists seem to be persistent in sediments there seem to have been no large increases in these chemicals in the Pohang area. © 2013. Published by Elsevier B.V. All rights reserved.

Multi-tiered system of support incorporating the R.E.N.E.W. process and its relationship to perception of school safety and office discipline referrals

NASA Astrophysics Data System (ADS)

Flood, Molly M.

This study examined the relationship between the fidelity of multi-tier school-wide positive behavior interventions and supports (SWPBIS) and staff perception of school safety and office discipline referrals. This research provided a case study on multi-tier supports and interventions, and the RENEW person-centered planning process in an alternative special education center following the implementation of a multi-tier SWPBIS model. Pennsylvania is one of several states looking to adopt an effective Tier III behavioral tool. The research described the results of an analysis of implementation fidelity on a multi-tiered school-wide positive behavior support model developed at a special education center operated by a public school system entity. This research explored the fidelity of SWPBIS implementation; analyzed the relationship of SWPBIS to school climate as measured by staff perceptions and reduction of office discipline referrals (ODR); explored tier III supports incorporating a process Rehabilitation and Empowerment, Natural Supports, Education and Work (RENEW); and investigated the potential sustainability of the RENEW process as a multi-tier system of support. This study investigated staff perceptions on integrated supports between schools and communities and identified the degree of relationship to school risk factors, school protective factors, and office discipline referrals following the building of cooperative partnerships between Systems of Care and Local Education Agencies.

Acute tier-1 and tier-2 effect assessment approaches in the EFSA Aquatic Guidance Document: are they sufficiently protective for insecticides?

PubMed

van Wijngaarden, René P A; Maltby, Lorraine; Brock, Theo C M

2015-08-01

The objective of this paper is to evaluate whether the acute tier-1 and tier-2 methods as proposed by the Aquatic Guidance Document recently published by the European Food Safety Authority (EFSA) are appropriate for deriving regulatory acceptable concentrations (RACs) for insecticides. The tier-1 and tier-2 RACs were compared with RACs based on threshold concentrations from micro/mesocosm studies (ETO-RAC). A lower-tier RAC was considered as sufficiently protective, if less than the corresponding ETO-RAC. ETO-RACs were calculated for repeated (n = 13) and/or single pulsed applications (n = 17) of 26 insecticides to micro/mesocosms, giving a maximum of 30 insecticide × application combinations (i.e. cases) for comparison. Acute tier-1 RACs (for 24 insecticides) were lower than the corresponding ETO-RACs in 27 out of 29 cases, while tier-2 Geom-RACs (for 23 insecticides) were lower in 24 out of 26 cases. The tier-2 SSD-RAC (for 21 insecticides) using HC5 /3 was lower than the ETO-RAC in 23 out of 27 cases, whereas the tier-2 SSD-RAC using HC5 /6 was protective in 25 out of 27 cases. The tier-1 and tier-2 approaches proposed by EFSA for acute effect assessment are sufficiently protective for the majority of insecticides evaluated. Further evaluation may be needed for insecticides with more novel chemistries (neonicotinoids, biopesticides) and compounds that show delayed effects (insect growth regulators). © 2014 Society of Chemical Industry.

[The human body burden of polychlorinated dibenzo-p-dioxins and dibenzofurans and dioxin-like polychlorinated biphenyls in residents' human breast milk from Beijing in 2007].

PubMed

Zhang, Lei; Liu, Yin-ping; Li, Jing-guang; Zhao, Yun-feng; Wu, Yong-ning

2013-06-01

To investigate contamination levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in human breast milk from Beijing residents, and evaluate the human body burden of PCDD/Fs and dl-PCBs of general population. A total of 110 human milk samples were collected from 11 regions in Beijing in 2007. After 11 pooled samples were made, concentrations of PCDD/Fs and dl-PCBs in breast milk pooled samples were measured by a high resolution gas chromatography - high resolution mass spectrometry (HRCG-HRMS) with isotope dilution. For congeners of PCDD/Fs and dl-PCBs in human breast milk from Beijing, the highest content of congeners was octachlorodibenzo-p-dioxin (OCDD), polychlorinated biphenyl (PCB)-118, and PCB-105 with the median of 20.6 pg/g fat, 4.07 ng/g fat and 1.63 ng/g fat, respectively. The concentration median of total dioxins in 11 pooled human milk samples from Beijing was 7.4 pg TEQ/g fat. The highest was 13.5 pg TEQ/g fat from Tongzhou, and the lowest was 4.3 pg TEQ/g fat from Pinggu. The contamination level of PCDD/Fs and dl-PCBs in human milk from Beijing is relatively low. However, with the rapid industrialization in China, the human body burden of PCDD/Fs and dl-PCBs will be likely to rise. Thus, further studies should be conducted to continuously monitor the trend of contamination level.

SIMULTANEOUS DETERMINATION OF PCDD/PCDF AND DIOXIN-LIKE PCBS IN EDIBLE VEGETABLE OILS

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) reassessment of the toxicity of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF) and dioxin-like polychlorinated biphenyls (PCB) identifies ingestion as a key route of human exposure to these compounds. The reassessme...

Review of State Soil Cleanup Levels for Dioxin (December 2009)

EPA Science Inventory

This final report summarizes a survey of state soil cleanup levels for dioxin and characterizes the science underlying these values. The objective of this project was to summarize existing state cleanup levels for dioxin in soil, together with their scientific bases where availa...

40 CFR 63.11432 - What General Provisions apply to this subpart?

Code of Federal Regulations, 2010 CFR

2010-07-01

... chromium, arsenic, dioxins, or methylene chloride, you must comply with the requirements of the General... new or existing affected source that uses any wood preservative containing chromium, arsenic, dioxins... uses any wood preservative containing chromium, arsenic, dioxins, or methylene chloride, you must...

EPA’s Science Plan for Activities Related to Dioxins in the Environment

EPA Science Inventory

The U.S. Environmental Protection Agency is currently addressing several issues related to dioxins and dioxin-like chemicals in the environment. These include the comprehensive human health and exposure as...

DOSE RESPONSE MODELING FOR 2, 3, 7, 8-TETRACHLORODIBENZO-P-DIOXIN

EPA Science Inventory

As science continues to appreciate the prevalence and power of dioxins, so it learns more about the harmful effects and effective preventive measures regarding these chemicals. Updating the acclaimed First Edition, Dioxins and Health, Second Edition covers the latest major scient...

Journal Article: Quality Assurance Considerations for An Ambient Dioxin Monitoring Network

EPA Science Inventory

The U.S. Environmental Protection Agency initiated the National Dioxin Air Monitoring Network (NDAMN) in 1998. NDAMN has three primary purposes:
1. To provide measurements of background atmospheric levels of dioxin-like compounds in different geographic regions of the Unite...

A NATIONAL SURVEY OF DIOXIN-LIKE COMPOUNDS IN THE U.S. MILK SUPPLY

EPA Science Inventory

The exposure portion of the United States Environmental Protection Agency's (EPA) Dioxin Reassessment has concluded that over 90% of human exposure to dioxin (and related compounds) occurs via food ingestion, primarily meats, dairy products, and fish. Therefore, EPA has undertak...

40 CFR 63.11432 - What General Provisions apply to this subpart?

Code of Federal Regulations, 2011 CFR

2011-07-01

... chromium, arsenic, dioxins, or methylene chloride, you must comply with the requirements of the General... new or existing affected source that uses any wood preservative containing chromium, arsenic, dioxins... uses any wood preservative containing chromium, arsenic, dioxins, or methylene chloride, you must...

DISTRIBUTION OF DIOXINS, FURANS, AND COPLANAR PCBS IN DIFFERENT FAT MATRICES IN CATTLE

EPA Science Inventory

The United States Environmental Protection Agency (EPA) and the United States Department of Agriculture (USDA) recently collaborated on a statistically-based, national survey of dioxin-like compounds, including dioxins, furans, and coplanar PCBs, in the back fat from slaughtered ...

Journal Article: Infant Exposure to Dioxin-Like Compounds in Breast Milk

EPA Science Inventory

A simple, one-compartment, first-order pharmacokinetic model is used to predict the infant body burden of dioxin-like compounds that results from breast-feeding. Validation testing of the model showed a good match between predictions and measurements of dioxin toxic equivalents ...

In utero exposure to dioxin causes neocortical dysgenesis through the actions of p27Kip1

PubMed Central

Mitsuhashi, Takayuki; Yonemoto, Junzo; Sone, Hideko; Kosuge, Yasuhiro; Kosaki, Kenjiro; Takahashi, Takao

2010-01-01

Dioxins have been reported to exert various adverse effects, including cell-cycle dysregulation in vitro and impairment of spatial learning and memory after in utero exposure in rodents. Furthermore, children born to mothers who are exposed to dioxin analogs polychlorinated dibenzofurans or polychlorinated biphenyls have developmental impairments in cognitive functions. Here, we show that in utero exposure to dioxins in mice alters differentiation patterns of neural progenitors and leads to decreased numbers of non-GABAergic neurons and thinner deep neocortical layers. This reduction in number of non-GABAergic neurons is assumed to be caused by accumulation of cyclin-dependent kinase inhibitor p27Kip1 in nuclei of neural progenitors. Lending support to this presumption, mice lacking p27Kip1 are not susceptible to in utero dioxin exposure. These results show that environmental pollutants may affect neocortical histogenesis through alterations of functions of specific gene(s)/protein(s) (in our case, dioxins), exerting adverse effects by altering functions of p27Kip1. PMID:20805476

Essential Features of Tier 2 Social-Behavioral Interventions

ERIC Educational Resources Information Center

Yong, Minglee; Cheney, Douglas A.

2013-01-01

The purpose of this study is to identify the essential features of Tier 2 interventions conducted within multitier systems of behavior support in schools. A systematic literature search identified 12 empirical studies that were coded and scored according to a list of Tier 2 specific RE-AIM criteria, related to the Reach, Effectiveness, Adoption,…

Positive Behavior Supports: Tier 2 Interventions in Middle Schools

ERIC Educational Resources Information Center

Hoyle, Carol G.; Marshall, Kathleen J.; Yell, Mitchell L.

2011-01-01

School personnel are using Schoolwide Positive Behavior Supports in public schools throughout the United States. A number of studies have evaluated the universal level, or Tier 1, of Schoolwide Positive Behavior Supports. In this study, the authors describe and analyze the interventions offered as options for use for Tier 2 in middle schools…

An introduction to indigenous health and culture: the first tier of the Three Tiered Plan.

PubMed

Sinnott, M J; Wittmann, B

2001-06-01

The objective of the present study was to prepare new doctors with an awareness of cultural and health issues to facilitate positive experiences with indigenous patients. The study incorporated the 1998 intern orientation programs in Queensland public hospitals. The study method included tier one of the Three Tiered Plan, which was implemented and audited. Indigenous liaison officers, directors of clinical training and medical education officers were surveyed prior to this implementation to determine whether any or similar initiatives had been carried out in previous years and/or were planned. Post-implementation feedback from interns was obtained by using questionnaires. Follow-up telephone interviews with the directors of clinical training, medical education officers and indigenous hospital liaison officers detailed the format and content of tier one at each hospital. The results indicate that this active intervention improved the implementation rate of tier one from nine of 19 (47%) Queensland public hospitals in 1997 to 17 (90%) in 1998. The 14 indigenous hospital liaison officers (100%) involved in the intervention perceived it as beneficial. Forty-three (67%) of interns who responded to the survey indicated they had encountered an indigenous patient within the last 2-4 months. The level of knowledge of indigenous health and culture self-reported by interns was between the categories 'enough to get by' and 'inadequate'. In conclusion, it appears that tier one has been successful and is to be a formal component of intern orientations in Queensland public hospitals. Further initiatives in indigenous health and culture targeting medical staff (i.e. tier two and tier three), are needed.

Assessment of dioxin-like activity in PM10 air samples from an industrial location in Algeria, using the DRE-CALUX bioassay.

PubMed

Khedidji, Sidali; Croes, Kim; Yassaa, Noureddine; Ladji, Riad; Denison, Michael S; Baeyens, Willy; Elskens, Marc

2017-05-01

When compared to the European guidelines, PM 10 (particulate matter up to 10-μm size) concentrations in Algeria are often exceeding the maximum limits, and in general, no information exists on the compounds bound on its surface. The objective of this study was to measure the dioxin-like activity of polychlorinated dibenzodioxines and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (PCBs) in the PM 10 fraction at the Sour El Ghozlane cement plant in Algeria. PM 10 samples (n = 23) were taken between 24 March and 15 April 2013, using a medium volume sampler and 47-mm PTFE filters. The 24-h samples were dried to determine the PM 10 content and afterward extracted, cleaned up, and analyzed with the dioxin-responsive element-chemical-activated luciferase gene expression (DRE-CALUX) bioassay. Our results showed that the measured bioanalytical equivalents (BEQs) were similar to those in other international industrial sites worldwide. The PCDD/Fs and dioxin-like PCBs (dl-PCBs) were positively correlated (rho = 0.6, p = 0.002), indicating that they have similar sources. Furthermore, samples from March showed higher PCDD/F and dl-PCB BEQs and humidity but lower temperatures compared to samples from April, while there was no difference in the PM 10 concentrations between the two months. These results reveal that PM 10 alone is not a good proxy and that meteorological conditions are an important factor in assessing dioxin-like pollution in the atmosphere. It seems that, at present, there is no health hazard through direct airborne human exposure to dioxin-like pollutants in PM 10 from this site. However, it is important to monitor these POPs for a longer period of time and also to gain more insight in their distribution between the particulate and gas phase in relation to meteorological conditions.

ANALYSIS OF ANIMAL- AND PLANT-DERIVED FEED INGREDIENTS FOR DIOXIN-LIKE COMPOUNDS

EPA Science Inventory

During a national survey of polychlorinated dibenzo-p-dioxins (CDD), dibenzofurans (CDF), and dioxin-like coplanar PCBs (PCB) in poultry, elevated concentrations above 20 parts per trillion (ppt) toxic equivalents (TEQ) were found in the fat of 2 broilers. These TEQ values were ...

40 CFR 60.59b - Reporting and recordkeeping requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... monitor mercury or dioxin/furan instead of conducting performance testing using EPA manual test methods, all integrated 24-hour mercury concentrations or all integrated 2-week dioxin/furan concentrations as... actions taken. (4) For affected facilities that apply activated carbon for mercury or dioxin/furan control...

COMPARING PCDDS, PCDFS, AND DIOXIN-LIKE PCBS IN FARM-RAISED AND WILD-CAUGHT CATFISH FROM SOUTHERN MISSISSIPPI

EPA Science Inventory

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) [hereafter referred to as ¿dioxin-like compounds¿] are persistent environmental contaminants that have been found to be ubiquitous in environmental media and bio...

DEVELOPMENT OF DIOXIN TOXICITY EVALUATION METHOD IN HUMAN MILK BY ENZYME-LINKED IMMUNOSORBENT ASSAY-ASSAY VALIDATION FOR HUMAN MILK. (R825433)

EPA Science Inventory

In this study, the development of a toxicity evaluation method for dioxins in human milk by enzyme-linked immunosorbent assay (ELISA) was reported. A total of 17 human milk samples were tested by ELISA and by gas chromatography/mass spectrometry (GC/MS) to assess whether the E...

Workshop on perinatal exposure to dioxin-like compounds. I. Summary.

PubMed Central

Lindström, G; Hooper, K; Petreas, M; Stephens, R; Gilman, A

1995-01-01

An international workshop reviewed 20 ongoing or recently completed studies of the effects of perinatal exposures to dioxins, dibenzofurans, and PCBs on the reproductive, endocrine, neurodevelopmental, and immune systems. Many of the observed effects are consistent with these compounds acting as "environmental hormones" or endocrine disrupters. This report summarizes the conclusions and future directions described at the workshop. PMID:7614935

TRENDS IN DIOXIN AND PCB CONCENTRATIONS IN MEAT SAMPLES FROM SEVERAL DECADES OF THE 20TH CENTURY

EPA Science Inventory

Data from several studies suggest that concentrations of dioxins rose in the environment from the 1930s to about the 1960s/70s and have been declining over the last decade or two. The most direct evidence of this trend is lake core sediments, with some other evidence from older...

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.

Analysis of dioxin-like compounds in vegetation and soil samples burned in Catalan forest fires. Comparison with the corresponding unburned material.

PubMed

Martínez, M; Díaz-Ferrero, J; Martí, R; Broto-Puig, F; Comellas, L; Rodríguez-Larena, M C

2000-12-01

Only a few data are reported about the formation of polychlorinated dibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) in forest fires. However, the inventories of sources undertaken by several European and American countries consider natural fires as a possible source of PCDD/F and, in some cases, as one of the most important. In our work we have analysed vegetation and soil samples burned in four forest fires which happened in Catalonia in the summer of 1998. The concentration of dioxin-like compounds (PCDD/F, non-ortho polychlorinated bi-phenyls (PCB) and mono-ortho PCB) has been compared to the concentration present in the corresponding unburned material collected in places near the fires but not affected. The results of this preliminary study show very low concentrations in all the samples, both burned and unburned. Although a change in the profile (proportional increase of tetrachlorinated congeners in PCDD/F) is observed in burned samples compared to unburned ones, the absolute values of concentration decrease in most samples. Therefore, natural fires seem not to be an important source of dioxin-like compounds. These results will be confirmed with air emissions measurements in future studies.

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

Examining the Effects and Feasibility of a Teacher-Implemented Tier 1 and Tier 2 Intervention in Word Reading, Fluency, and Comprehension

ERIC Educational Resources Information Center

Solari, Emily J.; Denton, Carolyn A.; Petscher, Yaacov; Haring, Christa

2018-01-01

This study investigates the effects and feasibility of an intervention for first-grade students at risk for reading difficulties or disabilities (RD). The intervention was provided by general education classroom teachers and consisted of 15 min whole-class comprehension lessons (Tier 1) and 30 min Tier 2 intervention sessions in word reading,…

Mathematics Intervention for First- and Second-Grade Students with Mathematics Difficulties: The Effects of Tier 2 Intervention Delivered as Booster Lessons

ERIC Educational Resources Information Center

Bryant, Diane Pedrotty; Bryant, Brian R.; Gersten, Russell; Scammacca, Nancy; Chavez, Melissa M.

2008-01-01

This study sought to examine the effects of Tier 2 intervention in a multitiered model on the performance of first- and second-grade students who were identified as having mathematics difficulties. A regression discontinuity design was utilized. Participants included 126 (Tier 2, n = 26) first graders and 140 (Tier 2, n = 25) second graders. Tier…

Examining the Predictive Validity of a Dynamic Assessment of Decoding to Forecast Response to Tier 2 Intervention

ERIC Educational Resources Information Center

Cho, Eunsoo; Compton, Donald L.; Fuchs, Douglas; Fuchs, Lynn S.; Bouton, Bobette

2014-01-01

The purpose of this study was to examine the role of a dynamic assessment (DA) of decoding in predicting responsiveness to Tier 2 small-group tutoring in a response-to-intervention model. First grade students (n = 134) who did not show adequate progress in Tier 1 based on 6 weeks of progress monitoring received Tier 2 small-group tutoring in…

To Wait in Tier 1 or Intervene Immediately: A Randomized Experiment Examining First Grade Response to Intervention (RTI) in Reading

ERIC Educational Resources Information Center

Al Otaiba, Stephanie; Connor, Carol M.; Folsom, Jessica S.; Wanzek, Jeanne; Greulich, Luana; Schatschneider, Christopher; Wagner, Richard K.

2015-01-01

This randomized control study compares the efficacy of two response-to-intervention (RTI) models: (1) Dynamic RTI, which immediately refers grade 1 students with the weakest skills to the most intensive intervention supports (Tier 2 or Tier 3); and (2) Typical RTI, which starts all students in Tier 1 and after 8 weeks, decides whether students who…

Journal Article: EPA's National Dioxin Air Monitoring Network (Ndamn): Design, Implementation, and Final Results

EPA Science Inventory

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 (...

Levels of CDDs, CDFs, PCBs and Hg in Rural Soils of US (Project Overview)

EPA Science Inventory

No systematic survey of dioxins in soil has been conducted in the US. Soils represent the largest reservoir source of dioxins. As point source emissions are reduced emissions from soils become increasingly important. Understanding the distribution of dioxin levels in soils is ...

HEALTH ASSESSMENT DOCUMENT FOR POLYCHLORINATED DIBENZO-P-DIOXINS (1985)

EPA Science Inventory

The health assessment document on polychlorinated dibenzo-p-dioxins discusses multimedia environmental issues pertaining to the most toxic chlorinated dioxins, namely, 2,3,7,8-tetrachloro-; 1,2,3,7,8-pentachloro-; 1,2,3,6,7,8-hexachloro-; and 1,2,3,7,8,9-hexachlorodibenzo-p-dioxi...

40 CFR 60.1900 - What must I include in the semiannual out-of-compliance reports?

Code of Federal Regulations, 2010 CFR

2010-07-01

... for dioxins/furans, cadmium, lead, mercury, particulate matter, opacity, hydrogen chloride, and... actions. (c) For municipal waste combustion units that apply activated carbon to control dioxins/furans or... carbon feed rate established during the most recent mercury and dioxins/furans stack test (as specified...

40 CFR 62.15250 - May I conduct stack testing less often?

Code of Federal Regulations, 2010 CFR

2010-07-01

... pollutants subject to stack testing requirements: dioxins/furans, cadmium, lead, mercury, particulate matter, opacity, hydrogen chloride, and fugitive ash. (b) You can test less often for dioxins/furans emissions if... municipal waste combustion units have demonstrated levels of dioxins/furans emissions less than or equal to...

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 (...

HIGHLY SENSITIVE DIOXIN IMMUNOASSAY AND ITS APPLICATIONS TO SOIL AND BIOTA SAMPLES. (R825433)

EPA Science Inventory

Tetrachlorodibenzo-p-dioxin (TCDD) is a well-known highly toxic compound that is present in nearly all components of the global ecosystem, including air, soil, sediment, fish and humans. Dioxin analysis is equipment intensive and expensive requiring low ppt or even ppq ...

AN EVALUATION OF THREE EMPIRICAL AIR-TO-LEAF MODELS FOR POLYCHLORINATED DIBENZO-P-DIOXINS AND DIBENZOFURANS

EPA Science Inventory

Three empirical air-to-leaf models for estimating grass concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (abbreviated dioxins and furans) from air concentrations of these compounds are described and tested against two field data sets. All are empirical in th...

TOXIC EQUIVALENCY APPROACH FOR DIOXINS: AN EXAMPLE OF DOSE ADDITIVITY

EPA Science Inventory

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD; dioxin) is often called the most toxic man-made compound. However, it is but the prototype for a family of structurally related compounds which have a common mechanism of action, induce a common spectrum of biological responses, and are...

PERFORMANCE OF THE CAPE TECHNOLOGIES DF1 DIOXIN/FURAN IMMUNOASSAY KIT FOR SOIL AND SEDIMENT SAMPLES

EPA Science Inventory

A demonstration of screening technologies for determining the presence of dioxin and dioxin-like compounds in soil and sediment was conducted under the U.S. Environmental Protection Agency’s (EPA’s) Superfund Innovative Technology Evaluation Program in Saginaw, Michigan in 2004. ...

Dioxins reformation and destruction in secondary copper smelting fly ash under ball milling

PubMed Central

Cagnetta, Giovanni; Hassan, Mohammed Mansour; Huang, Jun; Yu, Gang; Weber, Roland

2016-01-01

Secondary copper recovery is attracting increasing interest because of the growth of copper containing waste including e-waste. The pyrometallurgical treatment in smelters is widely utilized, but it is known to produce waste fluxes containing a number of toxic pollutants due to the large amount of copper involved, which catalyses the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (“dioxins”). Dioxins are generated in secondary copper smelters on fly ash as their major source, resulting in highly contaminated residues. In order to assess the toxicity of this waste, an analysis of dioxin-like compounds was carried out. High levels were detected (79,090 ng TEQ kg−1) in the ash, above the Basel Convention low POPs content (15,000 ng TEQ kg−1) highlighting the hazardousness of this waste. Experimental tests of high energy ball milling with calcium oxide and silica were executed to assess its effectiveness to detoxify such fly ash. Mechanochemical treatment obtained 76% dioxins reduction in 4 h, but longer milling time induced a partial de novo formation of dioxins catalysed by copper. Nevertheless, after 12 h treatment the dioxin content was substantially decreased (85% reduction) and the copper, thanks to the phenomena of incorporation and amorphization that occur during milling, was almost inactivated. PMID:26975802

Dioxins reformation and destruction in secondary copper smelting fly ash under ball milling

NASA Astrophysics Data System (ADS)

Cagnetta, Giovanni; Hassan, Mohammed Mansour; Huang, Jun; Yu, Gang; Weber, Roland

2016-03-01

Secondary copper recovery is attracting increasing interest because of the growth of copper containing waste including e-waste. The pyrometallurgical treatment in smelters is widely utilized, but it is known to produce waste fluxes containing a number of toxic pollutants due to the large amount of copper involved, which catalyses the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (“dioxins”). Dioxins are generated in secondary copper smelters on fly ash as their major source, resulting in highly contaminated residues. In order to assess the toxicity of this waste, an analysis of dioxin-like compounds was carried out. High levels were detected (79,090 ng TEQ kg-1) in the ash, above the Basel Convention low POPs content (15,000 ng TEQ kg-1) highlighting the hazardousness of this waste. Experimental tests of high energy ball milling with calcium oxide and silica were executed to assess its effectiveness to detoxify such fly ash. Mechanochemical treatment obtained 76% dioxins reduction in 4 h, but longer milling time induced a partial de novo formation of dioxins catalysed by copper. Nevertheless, after 12 h treatment the dioxin content was substantially decreased (85% reduction) and the copper, thanks to the phenomena of incorporation and amorphization that occur during milling, was almost inactivated.

Environmental sociology: fishermen of the Tittabawassee

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

Smith, B.F.; Thompson, W.N.

1984-06-01

The Tittabawassee River in Midland, Michigan is a popular body of water for fishermen. It is also the home of Dow Chemical. In 1979 Michigan State University began collecting samples of carp and suckers in order to study for dioxin contamination. Three years of study by MSU found levels of dioxin in the fish ranging from 17 to 332 parts per trillion. The Food and Drug Administration has set an ''action level'' of 25 ppt for dioxin. Above that, consumers are advised to eat limited amounts of fish. Above 50 ppt, the advice is to avoid eating any fish. But,more » the anglers have ignored the warnings and continue to fish and to eat the fish. The answer seems to be to educate the citizens to grasp the true dangers of pollution and to have programs of enforcement.« less

Exploring elementary school teachers' perception of their role in teaching content literacy in the elementary science and social studies classrooms: A mixed methods study

NASA Astrophysics Data System (ADS)

Jones-Moore, Lisa Michelle

2011-12-01

This mixed-methods study explored third, fourth, and fifth grade teachers' perceptions of their role in teaching content literacy in the elementary science and social studies classroom. The rationale for this study was the growing number of studies questioning the reliance on the inoculation theory for content area literacy comprehension. The study was a mixed methods study so as to provide insight into the participants' thought processes in decision making and instructional planning. Data sources included timed instructional observations, tiered checklist to identify strategy instruction, and prompted critical reflections. The three-tiered observation instrument categorized strategies used by teachers in tiers according to the focus of the strategy. Tier I strategies were those identified as strategies good readers use, typically taught with narrative text. The inoculation theory posits these skills transfer to reading informational and expository text. Tier II strategies were those identified as strategies appropriate for informational or expository text. Use of these strategies acknowledged that narrative and informational/expository text require different strategies, but does not differentiate between expository text drawn from particular content area. Tier III strategies were those identified as strategies particularly suited to informational or expository text drawn from specific content areas. These strategies embody cognitive processes used to comprehend text drawn from specific content areas. The findings showed the participating teachers used a preferential Tier of strategy instruction. Some participants felt that reading comprehension was more important than content. They viewed reading as a subject instead of an integral part of science and social studies instruction.

Prospective Environmental Risk Assessment for Sediment-Bound Organic Chemicals: A Proposal for Tiered Effect Assessment.

PubMed

Diepens, Noël J; Koelmans, Albert A; Baveco, Hans; van den Brink, Paul J; van den Heuvel-Greve, Martine J; Brock, Theo C M

A broadly accepted framework for prospective environmental risk assessment (ERA) of sediment-bound organic chemicals is currently lacking. Such a framework requires clear protection goals, evidence-based concepts that link exposure to effects and a transparent tiered-effect assessment. In this paper, we provide a tiered prospective sediment ERA procedure for organic chemicals in sediment, with a focus on the applicable European regulations and the underlying data requirements. Using the ecosystem services concept, we derived specific protection goals for ecosystem service providing units: microorganisms, benthic algae, sediment-rooted macrophytes, benthic invertebrates and benthic vertebrates. Triggers for sediment toxicity testing are discussed.We recommend a tiered approach (Tier 0 through Tier 3). Tier-0 is a cost-effective screening based on chronic water-exposure toxicity data for pelagic species and equilibrium partitioning. Tier-1 is based on spiked sediment laboratory toxicity tests with standard benthic test species and standardised test methods. If comparable chronic toxicity data for both standard and additional benthic test species are available, the Species Sensitivity Distribution (SSD) approach is a more viable Tier-2 option than the geometric mean approach. This paper includes criteria for accepting results of sediment-spiked single species toxicity tests in prospective ERA, and for the application of the SSD approach. We propose micro/mesocosm experiments with spiked sediment, to study colonisation success by benthic organisms, as a Tier-3 option. Ecological effect models can be used to supplement the experimental tiers. A strategy for unifying information from various tiers by experimental work and exposure-and effect modelling is provided.

[Correlation of Persistent Free Radicals, PCDD/Fs and Metals in Waste Incineration Fly Ash].

PubMed

Wang, Tian-jiao; Chen, Tong; Zhan, Ming-xiu; Guo, Ying; Li, Xiao-dong

2016-03-15

Environmentally persistent free radicals (EPFRs) are relatively highly stable and found in the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). Recent studies have concentrated on model dioxin formation reactions and there are few studies on actual waste incineration fly ash. In order to study EPFRs and the correlation with dioxins and heavy metals in waste incineration fly ash, the spins of EPFRs, concentration of PCDD/Fs and metals in samples from 6 different waste incinerators were detected. The medical waste incineration fly ash from Tianjin, municipal solid waste incineration fly ash from Jiangxi Province, black carbon and slag from municipal solid waste incinerator in Lanxi, Zhejiang Province, all contained EPFRs. Above all the signal in Tianjin sample was the strongest. Hydroxyl radicals, carbon-center radicals and semiquinone radicals were detected. Compared with other samples, Jiangxi fly ash had the highest toxic equivalent quantity (TEQ) of dioxins, up to 7.229 4 ng · g⁻¹. However, the dioxin concentration in the Tianjin sample containing the strongest EPFR signals was only 0.092 8 ng · g⁻¹. There was perhaps little direct numeric link between EPFRs and PCDD/Fs. But the spins of EPFRs in samples presented an increasing trend as the metal contents increased, especially with Al, Fe, Zn. The signal strength of radicals was purposed to be related to the metal contents. The concentration of Zn (0.813 7% ) in the Tianjin sample was the highest and this sample contained much more spins of oxygen-center radicals. We could presume the metal Zn had a greater effect on the formation of EPFRs, and was easier to induce the formation of radicals with a longer half-life period.

Inhalation Exposure to Dioxins and dl-PCBs Depending on the Season in Upper Silesia, Poland: A Pilot Study.

PubMed

Dziubanek, Grzegorz; Marchwińska, Ewa; Hajok, Ilona; Piekut, Agata

2016-06-01

The aim of this study was to investigate the seasonal fluctuation of PCDD/Fs and dl-PCBs levels in the ambient air of Upper Silesia in the aspect of human inhalation exposure as well as the estimation of health risk attributed to this exposure pathway to dioxins and dl-PCBs. In the study air samples were taken in five urban districts of Upper Silesia, Poland, where the houses are heated with coal. The same sampling points in summer and winter were analyzed for dioxins/furans and dl-PCBs. In addition, information was collected on awareness of the residents about the co-incineration of plastic waste and effects of this activity on human health. The results show that the average daily exposure of residents of Upper Silesia to TCDD and DLCs in the heating season was about 6.5.-fold higher than in summer. The risk assessment showed that expected excess of cancer cases per 1,000,000 people ranged from 4.5 to 13.2 in winter and from 0.9 to 2.1 in summer. The practice of mixing waste with coal for houses heating has been confirmed by investigated families, who do not associate it with the possibility of negative health effects. Air pollution can be a significant source of dioxin and dl-PCB for people during the winter season, as a result of co-burning coal and waste containing plastics. The dose of dioxins inhaled through the respiratory pathway in winter can be associated with the higher cancer risk in the population of Upper Silesia. Copyright© by the National Institute of Public Health, Prague 2015.

76 FR 33380 - Self-Regulatory Organizations; NYSE Arca, Inc.; Notice of Filing and Immediate Effectiveness of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-08

... Two New Pricing Tiers, Investor Tier 1 and Investor Tier 2 June 3, 2011. Pursuant to Section 19(b)(1... Services (the ``Schedule'') to introduce two new pricing tiers, Investor Tier 1 and Investor Tier 2. The... proposes to introduce two new pricing tier levels, Investor Tier 1 and Investor Tier 2. Investor Tier 1...

Formation of dioxins during the combustion of newspapers in the presence of sodium chloride and poly(vinyl chloride).

PubMed

Yasuhara, A; Katami, T; Okuda, T; Ohno, N; Shibamoto, T

2001-04-01

Exhaust gases from the combustion of newspaper alone, from branches of London plane tree alone, and from newspapers mixed with sodium chloride (NaCl), polyethylene, or poly(vinyl chloride) (PVC) were collected. The samples were analyzed for dioxins by gas chromatography/mass spectrometry. Total amounts of dioxins found in the samples were 0.186 ng/g from newspapers alone, 1.42 ng/g from the branches of London plane, 102 ng/g from newspapers impregnated with sodium chloride (CI wt % = 3.1), 101 ng/g from newspapers impregnated with sodium chloride mixed with PVC (Cl wt % = 2.6), and 146 ng/g from newspapers mixed with PVC (Cl wt % = 5.1). Samples with a higher chloride content produced more dioxins, and there is a clear correlation between dioxin formation and chloride content. The amount of dioxins formed in the samples according to the number of chlorides was Cl5 > Cl4 > Cl6 > Cl7 > Cl8 in PCDD isomers and Cl4 > Cl5 > Cl6 > Cl7 > Cl8 in PCDF isomers, except in the case of newspapers alone. Benzofurans composed 78-92% of the total dioxins formed in the exhaust gases. The higher the number of the chlorides, the lower the production of benzofuran observed. NaCl vaporized at the temperature of the flame used for combustion of the samples (760-1080 degrees C). The results indicate that NaCl and PVC contribute significantly to dioxin formation from waste materials combusted in incinerators.

Contaminant levels in Norwegian farmed Atlantic salmon (Salmo salar) in the 13-year period from 1999 to 2011.

PubMed

Nøstbakken, Ole Jakob; Hove, Helge T; Duinker, Arne; Lundebye, Anne-Katrine; Berntssen, Marc H G; Hannisdal, Rita; Lunestad, Bjørn Tore; Maage, Amund; Madsen, Lise; Torstensen, Bente E; Julshamn, Kåre

2015-01-01

Environmental pollutants such as dioxins and PCBs, heavy metals, and organochlorine pesticides are a global threat to food safety. In particular, the aquatic biota can bioaccumulate many of these contaminants potentially making seafood of concern for chronic exposure to humans. The main objective was to evaluate trends of contaminant levels in Norwegian farmed Atlantic salmon in light of the derived tolerable intakes. Through an EU-instigated surveillance programme, the Norwegian Food Safety Authority (NFSA) has between 1999 and 2011 collected more than 2300 samples of Norwegian farmed Atlantic salmon (Salmo salar) for contaminant analyses. The fillets of these fish were homogenised and analysed for dioxins, PCBs, heavy metals and organochlorine pesticides. The levels of the contaminants mercury, arsenic, dioxins, dioxin-like PCBs and DDT in Norwegian farmed salmon fillet have decreased during our period of analyses. The levels of cadmium, lead and several organochlorine pesticides were too close to the limit of quantification to calculate time trends. For PCB6 and quantifiable amounts of pesticides, except DDT, stable levels were observed. The contaminant levels in Norwegian farmed salmon have generally decreased between 1999 and 2011. Excluding other dietary sources, the levels of dioxins and dioxin-like PCBs in 2011 allowed consumption of up to 1.3kg salmon per week to reach the tolerable weekly intake. The group of contaminants which was the limiting factor for safe consumption of Norwegian farmed salmon, based on currently established TWI values, is the sum of dioxins and dioxin-like PCBs. Copyright © 2014. Published by Elsevier Ltd.

Single-tier testing with the C6 peptide ELISA kit compared with two-tier testing for Lyme disease.

PubMed

Wormser, Gary P; Schriefer, Martin; Aguero-Rosenfeld, Maria E; Levin, Andrew; Steere, Allen C; Nadelman, Robert B; Nowakowski, John; Marques, Adriana; Johnson, Barbara J B; Dumler, J Stephen

2013-01-01

For the diagnosis of Lyme disease, the 2-tier serologic testing protocol for Lyme disease has a number of shortcomings including low sensitivity in early disease; increased cost, time, and labor; and subjectivity in the interpretation of immunoblots. In this study, the diagnostic accuracy of a single-tier commercial C6 ELISA kit was compared with 2-tier testing. The results showed that the C6 ELISA was significantly more sensitive than 2-tier testing with sensitivities of 66.5% (95% confidence interval [CI] 61.7-71.1) and 35.2% (95% CI 30.6-40.1), respectively (P < 0.001) in 403 sera from patients with erythema migrans. The C6 ELISA had sensitivity statistically comparable to 2-tier testing in sera from Lyme disease patients with early neurologic manifestations (88.6% versus 77.3%, P = 0.13) or arthritis (98.3% versus 95.6%, P = 0.38). The specificities of C6 ELISA and 2-tier testing in over 2200 blood donors, patients with other conditions, and Lyme disease vaccine recipients were found to be 98.9% and 99.5%, respectively (P < 0.05, 95% CI surrounding the 0.6 percentage point difference of 0.04 to 1.15). In conclusion, using a reference standard of 2-tier testing, the C6 ELISA as a single-step serodiagnostic test provided increased sensitivity in early Lyme disease with comparable sensitivity in later manifestations of Lyme disease. The C6 ELISA had slightly decreased specificity. Future studies should evaluate the performance of the C6 ELISA compared with 2-tier testing in routine clinical practice. Copyright © 2013 Elsevier Inc. All rights reserved.

Tiers of intervention in kindergarten through third grade.

PubMed

O'Connor, Rollanda E; Harty, Kristin R; Fulmer, Deborah

2005-01-01

This study measured the effects of increasing levels of intervention in reading for a cohort of children in Grades K through 3 to determine whether the severity of reading disability (RD) could be significantly reduced in the catchment schools. Tier 1 consisted of professional development for teachers of reading. The focus of this study is on additional instruction that was provided as early as kindergarten for children whose achievement fell below average. Tier 2 intervention consisted of small-group reading instruction 3 times per week, and Tier 3 of daily instruction delivered individually or in groups of two. A comparison of the reading achievement of third-grade children who were at risk in kindergarten showed moderate to large differences favoring children in the tiered interventions in decoding, word identification, fluency, and reading comprehension.

Release of chlorinated, brominated and mixed halogenated dioxin-related compounds to soils from open burning of e-waste in Agbogbloshie (Accra, Ghana).

PubMed

Tue, Nguyen Minh; Goto, Akitoshi; Takahashi, Shin; Itai, Takaaki; Asante, Kwadwo Ansong; Kunisue, Tatsuya; Tanabe, Shinsuke

2016-01-25

Although complex mixtures of dioxin-related compounds (DRCs) can be released from informal e-waste recycling, DRC contamination in African e-waste recycling sites has not been investigated. This study examined the concentrations of DRCs including chlorinated, brominated, mixed halogenated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs, PBDD/Fs, PXDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in surface soil samples from the Agbogbloshie e-waste recycling site in Ghana. PCDD/F and PBDD/F concentrations in open burning areas (18-520 and 83-3800 ng/g dry, respectively) were among the highest reported in soils from informal e-waste sites. The concentrations of PCDFs and PBDFs were higher than those of the respective dibenzo-p-dioxins, suggesting combustion and PBDE-containing plastics as principal sources. PXDFs were found as more abundant than PCDFs, and higher brominated analogues occurred at higher concentrations. The median total WHO toxic equivalent (TEQ) concentration in open burning soils was 7 times higher than the U.S. action level (1000 pg/g), with TEQ contributors in the order of PBDFs>PCDD/Fs>PXDFs. DRC emission to soils over the e-waste site as of 2010 was estimated, from surface soil lightness based on the correlations between concentrations and lightness, at 200mg (95% confidence interval 93-540 mg) WHO-TEQ over three years. People living in Agbogbloshie are potentially exposed to high levels of not only chlorinated but also brominated DRCs, and human health implications need to be assessed in future studies. Copyright © 2015 Elsevier B.V. All rights reserved.

75 FR 7591 - Guidance on Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at CERCLA and...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-22

... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-SFUND-2009-0907; FRL-9114-6] RIN 2050-ZA05 Guidance on Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at CERCLA and RCRA Sites; Extension of... Interim Preliminary Remediation Goals for Dioxin in Soil at Comprehensive Environmental Response...

EVALUATING TERRESTRIAL FOOD CHAIN IMPACTS NEAR SOURCES OF DIOXIN RELEASE IN U.S. EPA RISK ASSESSMENTS

EPA Science Inventory

Prior to the mid 1980s, assessments of health impacts from dioxin-like compounds released into the air only evaluated the inhalation exposure pathway. In the latter 1980s it was demonstrated that consumption of animal food products is the principal source of exposure to dioxin...

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...

Overview of Dioxin Kinetics and Application of Dioxin Physiologically Based Phannacokinetic (PBPK) Models to Risk Assessment

EPA Science Inventory

The available data on the pharmacokinetics of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in animals and humans have been thoroughly reviewed in literature. It is evident based on these reviews and other analyses that three distinctive features of TCDD play important roles in dete...

THERMAL TREATMENT OF 1,2,3,4-TETRACHLORODIBENZO-P- DIOXIN BY REACTION WITH CA-BASED SORBENTS AT 23-300 DEGREES °C

EPA Science Inventory

The fate of combustion-generated polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans captured in sorbent-based, air pollution control devices remains uncertain. This process was simulated by passing vapor-phase 1,2,3,4-tetrachlorinated dibenzo-p-dioxin (TCDD) to a...

Final Report on the Performance of the Eichrom Technologies Procept® Rapid Dioxin Assay for Soil and Sediment Samples

EPA Science Inventory

A demonstration of screening technologies for determining the presence of dioxin and dioxin-like compounds in soil and sediment was conducted under the U.S. Environmental Protection Agency’s (EPA’s) Superfund Innovative Technology Evaluation Program in Saginaw, Michigan in 2004. ...

40 CFR 62.14109 - Reporting and recordkeeping and compliance and performance testing.

Code of Federal Regulations, 2010 CFR

2010-07-01

... dioxin/furan emissions specified in paragraph (d)(1) of this section. (1) If all performance tests for all affected facilities at the MWC plant over a 2-year period indicate that dioxin/furan emissions are... test for dioxin/furan emissions shall be conducted annually (no more than 12 months following the...

40 CFR 60.1875 - What must I include in my initial report?

Code of Federal Regulations, 2010 CFR

2010-07-01

... in table 2 or 4 of this subpart): (1) Dioxins/furans. (2) Cadmium. (3) Lead. (4) Mercury. (5) Opacity... particulate matter control device. Use values established during your initial stack test for dioxins/furans... carbon to control dioxins/furans or mercury emissions, the average carbon feed rates that you recorded...

40 CFR 60.1885 - What must I include in my annual report?

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Dioxins/furans. (2) Cadmium. (3) Lead (4) Mercury. (5) Opacity. (6) Particulate matter. (7) Hydrogen... controlling dioxins/furans or mercury emissions, include four records: (1) The average carbon feed rates recorded during the most recent dioxins/furans and mercury stack tests. (2) The lowest 8-hour block average...

40 CFR 60.1410 - What must I include in my annual report?

Code of Federal Regulations, 2010 CFR

2010-07-01

... units, for eight pollutants, as recorded under § 60.1360(a): (1) Dioxins/furans. (2) Cadmium. (3) Lead...) For municipal waste combustion units that use activated carbon for controlling dioxins/furans or... dioxins/furans and mercury stack tests. (2) The lowest 8-hour block average carbon feed rate recorded...

40 CFR 62.14452 - What test methods and procedures must I use?

Code of Federal Regulations, 2010 CFR

2010-07-01

... total dioxin/furan emissions. The minimum sample time must be 4 hours per test run. If you have selected the toxic equivalency standards for dioxin/furans under § 62.14411, you must use the following procedures to determine compliance: (1) Measure the concentration of each dioxin/furan tetra-through octa...

40 CFR 62.15355 - What must I include in the semiannual out-of-compliance reports?

Code of Federal Regulations, 2010 CFR

2010-07-01

... this subpart as applicable for dioxins/furans, cadmium, lead, mercury, particulate matter, opacity... control dioxins/furans or mercury emissions, include two items: (1) Documentation of all dates when the 8...) is less than the highest carbon feed rate established during the most recent mercury and dioxins...

Cytochrome P4501A1 is Required for Vascular Dysfunction and Hypertension Induced by 2,3,7,8-Tetrachlorodibenzo-p-dioxin

USDA-ARS?s Scientific Manuscript database

National Health and Nutrition Examination Survey data show an association between hypertension and exposure to dioxin-like halogenated aromatic hydrocarbons (HAH). Further, chronic exposure of mice to the prototypical HAH, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), induces reactive oxygen species (...

76 FR 6784 - Science Advisory Board Staff Office; Notification of Two Public Teleconferences of the Science...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-08

... Two Public Teleconferences of the Science Advisory Board Dioxin Review Panel AGENCY: Environmental... two public teleconferences of the SAB Dioxin Review Panel to discuss its draft advisory report concerning EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments, External...

40 CFR 60.1400 - What must I include in my initial report?

Code of Federal Regulations, 2010 CFR

2010-07-01

... parameters (use appropriate units as specified in table 2 of this subpart): (1) Dioxins/furans. (2) Cadmium... stack test for dioxins/furans emissions and include supporting calculations. (f) If your municipal waste combustion unit uses activated carbon to control dioxins/furans or mercury emissions, the average carbon feed...

40 CFR 62.14455 - What if my HMIWI goes outside of a parameter limit?

Code of Federal Regulations, 2010 CFR

2010-07-01

... temperature (3-hour rolling average) simultaneously The PM, CO, and dioxin/furan emission limits. (c) Except..., daily average for batch HMIWI), and below the minimum dioxin/furan sorbent flow rate (3-hour rolling average) simultaneously The dioxin/furan emission limit. (3) Operates above the maximum charge rate (3...

40 CFR 62.15330 - What must I include in the initial report?

Code of Federal Regulations, 2010 CFR

2010-07-01

... appropriate units as specified in tables 2 or 4 of this subpart): (1) Dioxins/furans. (2) Cadmium. (3) Lead... for dioxins/furans emissions and include supporting calculations. (f) If your municipal waste combustion unit uses activated carbon to control dioxins/furans or mercury emissions, the average carbon feed...

40 CFR 62.15340 - What must I include in the annual report?

Code of Federal Regulations, 2010 CFR

2010-07-01

... § 62.15300(a): (1) Dioxins/furans. (2) Cadmium. (3) Lead. (4) Mercury. (5) Opacity. (6) Particulate... combustion units that use activated carbon for controlling dioxins/furans or mercury emissions, include four records: (1) The average carbon feed rates recorded during the most recent dioxins/furans and mercury...

Evaluation of Background Exposures of Americans to Dioxin-Like Compounds in the 1990's and the 2000's

USDA-ARS?s Scientific Manuscript database

The US Environmental Protection Agency’s 2004 Dioxin Reassessment included a characterization of background exposures to dioxin-like compounds, including an estimate of an average background intake dose and an average background body burden. These quantities were derived from data generated in the m...

40 CFR 60.1305 - May I conduct stack testing less often?

Code of Federal Regulations, 2010 CFR

2010-07-01

...: dioxins/furans, cadmium, lead, mercury, particulate matter, opacity, hydrogen chloride, and fugitive ash. (b) You can test less often for dioxins/furans emissions if you own or operate a municipal waste... levels of dioxins/furans emissions less than or equal to 7 nanograms per dry standard cubic meter (total...

INTERIM REPORT ON THE EVOLUTION AND PERFORMANCE OF THE EICHROM TECHNOLOGIES PROCEPT RAPID DIOXIN ASSAY FOR SOIL AND SEDIMENT SAMPLES

EPA Science Inventory

A demonstration of screening technologies for determining the presence of dioxin and dioxin-like compounds in soil and sediment was conducted under the U.S. Environmental Protection Agency's(EPA's) Superfund Innovative Technology Evaluation Program in Saginaw, Michigan in 2004. T...

DEMONSTRATION AND QUALITY ASSURANCE PROJECT PLAN TECHNOLOGIES FOR THE MONITORING AND MEASUREMENT OF DIOXIN AND DIOXIN-LIKE COMPOUNDS IN SOIL AND SEDIMENT

EPA Science Inventory

The demonstration of technologies for determining the presence of dioxin in soil and sediment is being conducted under the U.S. Environmental Protection Agency Superfund Innovative Technology Evaluation Program in Saginaw, Michigan, at Green Point Environmental Learning Center fr...

THE 2005 WORLD HEALTH ORGANIZATION RE-EVALUATION OF HUMAN AND MAMMALIAN TOXIC EQUIVALENCY FACTORS FOR DIOXINS AND DIOXIN-LIKE COMPOUNDS

EPA Science Inventory

In June 2005 a WHO-IPCS expert meeting was held in Geneva during which the toxic equivalency factors (TEFs) for dioxin like compounds, including some polychlorinated biphenyls (PCBs), were re-evaluated. For this re-evaluation process the refined TEF database recently published by...

AN ASSESSMENT OF DIOXIN LEVELS IN PROCESSED BALL CLAY FROM THE U.S.

EPA Science Inventory

The presence of dioxin-like compounds in ball clay was discovered in 1996 as a result of an investigation to determine the sources of elevated levels of dioxin found in two chicken fat samples from a national survey of poultry. The investigation indicated that soybean meal added...

GAS CHROMATOGRAPHIC/MASS SPECTROMETRIC APPROACH FOR ISOMER-SPECIFIC ENVIRONMENTAL MONITORING OF THE 1700 BROMO-, CHLORO-, AND BROMOCHLORO-DIBENZO-P-DIOXINS

EPA Science Inventory

A combined approach using gas chromatographic retention indices and mass spectrometric characteristics has been elaborated for the isomer-specific identification of the 1700 bromo-, chloro- and bromochloro-dioxins which may be found in the environment. ver 100 dioxins were synthe...

The Inventory of Sources of Dioxin in the United States (External Review Draft 2005)

EPA Science Inventory

Background

The purpose of The Inventory of Sources of Dioxin in the United States (2005 External Review Draft) is to present the most current inventory of sources and environmental releases of dioxi...

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...

TECHNOLOGIES FOR MONITORING AND MEASUREMENT OF DIUOXIN AND DIOXIN-LIKE COMPOUNDS IN SOIL AND SEDIMENT. ABRAXIS LLC COPLANAR PCB ELISA KIT

EPA Science Inventory

A demonstration of technologies for determining the presence of dioxin and dioxin-like compounds in soil and sediment was conducted under EPA's Superfund Innovative Technology Evaluation Program in Saginaw, Michigan in April 2004. This report describes the performance evaluation ...

Dioxins and dioxin-like compounds in composts and digestates from European countries as determined by the in vitro bioassay and chemical analysis.

PubMed

Beníšek, Martin; Kukučka, Petr; Mariani, Giulio; Suurkuusk, Gert; Gawlik, Bernd M; Locoro, Giovanni; Giesy, John P; Bláha, Luděk

2015-03-01

Aerobic composting and anaerobic digestion plays an important role in reduction of organic waste by transforming the waste into humus, which is an excellent soil conditioner. However, applications of chemical-contaminated composts on soils may have unwanted consequences such as accumulation of persistent compounds and their transfer into food chains. The present study investigated burden of composts and digestates collected in 16 European countries (88 samples) by the compounds causing dioxin-like effects as determined by use of an in vitro transactivation assay to quantify total concentrations of aryl hydrocarbon receptor-(AhR) mediated potency. Measured concentrations of 2,3,7,8-Tetrachlorodibeno-p-dioxin (2,3,7,8-TCDD) equivalents (TEQbio) were compared to concentrations of polycyclic aromatic hydrocarbons (PAHs) and selected chlorinated compounds, including polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), co-planar polychlorinated biphenyls (PCBs), indicator PCB congeners and organochlorine pesticides (OCPs). Median concentrations of TEQbio (dioxin-like compounds) determined by the in vitro assay in crude extracts of various types of composts ranged from 0.05 to 1.2 with a maximum 8.22μg (TEQbio)kg(-1) dry mass. Potencies were mostly associated with less persistent compounds such as PAHs because treatment with sulfuric acid removed bioactivity from most samples. The pan-European investigation of contamination by organic contaminants showed generally good quality of the composts, the majority of which were in compliance with conservative limits applied in some countries. Results demonstrate performance and added value of rapid, inexpensive, effect-based monitoring, and points out the need to derive corresponding effect-based trigger values for the risk assessment of complex contaminated matrices such as composts. Copyright © 2014 Elsevier Ltd. All rights reserved.

A DOSE–RESPONSE ANALYSIS OF THE REPRODUCTIVE EFFECTS OF A SINGLE GESTATIONAL DOSE OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN IN MALE LONG EVANS HOODED RAT OFFSPRING

EPA Science Inventory

Male rats exposed in utero to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) display reduced fertility as a consequence of the direct action of TCDD on the epididymides, as well as delayed puberty and altered reproductive organ weights. The current study provides dose-response data f...

A Three-Tier Model of Integrated Behavior and Learning Supports: Linking System-Wide Implementation to Student Outcomes

ERIC Educational Resources Information Center

Harms, Anna Leigh Shon

2010-01-01

This study explored elementary schools' implementation of an integrated three-tier model of reading and behavior supports as they participated with a statewide Response to Intervention (RtI) project. The purpose of the study was to examine the process of implementing an integrated three-tier model and to explore the relation between implementation…

Triple quadrupole tandem mass spectrometry: A real alternative to high resolution magnetic sector instrument for the analysis of polychlorinated dibenzo-p-dioxins, furans and dioxin-like polychlorinated biphenyls.

PubMed

García-Bermejo, Ángel; Ábalos, Manuela; Sauló, Jordi; Abad, Esteban; González, María José; Gómara, Belén

2015-08-19

This paper reports on the optimisation, characterisation, validation and applicability of gas chromatography coupled to triple quadrupole mass spectrometry in its tandem operation mode (GC-QqQ(MS/MS) for the quantification of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs, dioxins) and dioxin-like polychlorinated biphenyls (DL-PCBs) in environmental and food matrices. MS/MS parameters were selected to achieve the high sensitivity and selectivity required for the analysis of this type of compounds and samples. Good repeatability for areas (RSD = 1-10%, for PCDD/Fs and DL-PCBs) and for ion transition ratios (RSD = 0.3-10%, for PCDD/Fs, and 0.2-15%, for DL-PCBs) and low instrumental limits of detection, 0.07-0.75 pg μL(-1) (for dioxins) and 0.05-0.63 pg μL(-1) (for DL-PCBs), were obtained. A comparative study of the congener specific determination using both GC-QqQ(MS/MS) and gas chromatography-high resolution mass spectrometry (GC-HRMS) was also performed by analysing several fortified samples and certified reference materials (CRMs) with low (feed and foodstuffs), median (sewage sludge) and high (fly ash) toxic equivalency (TEQ) concentration levels, i.e. 0.60, 1.83, 72.9 and 3609 pg WHO-TEQ(PCDD/Fs) g(-1). The agreement between the results obtained for the total TEQs (dioxins) on GC-QqQ(MS/MS) and GC-HRMS in all the investigated samples were within the range of ±4%, and that of DL-PCBs at concentration levels of 0.84 pg WHO-TEQs (DL-PCBs) g(-1), in the case of feedstuffs, was 0.11%. Both instrumental methods have similar and comparable linearity, precision and accuracy. The GC-QqQ(MS/MS) sensitivity, lower than that of GC-HRMS, is good enough (iLODs in the down to low pg levels) to detect the normal concentrations of these compounds in food and environmental samples. These results make GC-QqQ(MS/MS) suitable for the quantitative analysis of dioxins and DL-PCBs and a real alternative tool to the reference sector HRMS instruments. Copyright © 2015 Elsevier B.V. All rights reserved.

Enhancing the response of CALUX and CAFLUX cell bioassays for quantitative detection of dioxin-like compounds

PubMed Central

ZHAO, Bin; BASTON, David S.; KHAN, Elaine; SORRENTINO, Claudio; DENISON, Michael S.

2011-01-01

Reporter genes produce a protein product in transfected cells that can be easily measured in intact or lysed cells and they have been extensively used in numerous basic and applied research applications. Over the past 10 years, reporter gene assays have been widely accepted and used for analysis of 2,3,7,8-tetrachlorodibenzo-p-dioxin and related dioxin-like compounds in various types of matrices, such as biological, environmental, food and feed samples, given that high-resolution instrumental analysis techniques are impractical for large-scale screening analysis. The most sensitive cell-based reporter gene bioassay systems developed are the mechanism-based CALUX (Chemically Activated Luciferase Expression) and CAFLUX (Chemically Activated Fluorescent Expression) bioassays, which utilize recombinant cell lines containing stably transfected dioxin (AhR)-responsive firefly luciferase or enhanced green fluorescent protein (EGFP) reporter genes, respectively. While the current CALUX and CAFLUX bioassays are very sensitive, increasing their lower limit of sensitivity, magnitude of response and dynamic range for chemical detection would significantly increase their utility, particularly for those samples that contain low levels of dioxin-like HAHs (i.e., serum). In this study, we report that the addition of modulators of cell signaling pathways or modification of cell culture conditions results in significant improvement in the magnitude and overall responsiveness of the existing CALUX and CAFLUX cell bioassays. PMID:21394221

Dioxins, furans, biphenyls, arsenic, thorium and uranium in natural and anthropogenic sources of phosphorus and calcium used in agriculture.

PubMed

Avelar, A C; Ferreira, W M; Pemberthy, D; Abad, E; Amaral, M A

2016-05-01

The aim of this study was to assess the presence of dioxins, furans and biphenyls, and the inorganic contaminants such as arsenic (As), thorium (Th) and uranium (U) in three main products used in Agriculture in Brazil: feed grade dicalcium phosphate, calcined bovine bone meal and calcitic limestone. The first two are anthropogenic sources of phosphorus and calcium, while calcitic limestone is a natural unprocessed mineral. Regarding to dioxin-like substances, all samples analyzed exhibited dioxins (PCDD) and furans (PCDF) and dioxin-like polychlorinated biphenyls (dl-PCBs) concentrations below limit of detection (LOD). In general, achieved is in accordance with regulation in Brazil where is established a maximum limit in limestone used in the citric pulp production (0.50pg WHO-TEQ g(-1)). In addition, reported data revealed very low levels for limestone in comparison with similar materials reported by European legislation. As result for toxic metals, achieved data were obtained using Instrumental Neutron Activation Analysis (INAA). On one hand, limestone sample exhibits the largest arsenic concentration. On another hand, dicalcium phosphate exhibited the largest uranium concentration, which represents a standard in animal nutrition. Therefore, it is phosphorus source in the animal feed industry can be a goal of concern in the feed field. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparison of adsorption behavior of PCDD/Fs on carbon nanotubes and activated carbons in a bench-scale dioxin generating system.

PubMed

Zhou, Xujian; Li, Xiaodong; Xu, Shuaixi; Zhao, Xiyuan; Ni, Mingjiang; Cen, Kefa

2015-07-01

Porous carbon-based materials are commonly used to remove various organic and inorganic pollutants from gaseous and liquid effluents and products. In this study, the adsorption of dioxins on both activated carbons and multi-walled carbon nanotube was internally compared, via series of bench scale experiments. A laboratory-scale dioxin generator was applied to generate PCDD/Fs with constant concentration (8.3 ng I-TEQ/Nm(3)). The results confirm that high-chlorinated congeners are more easily adsorbed on both activated carbons and carbon nanotubes than low-chlorinated congeners. Carbon nanotubes also achieved higher adsorption efficiency than activated carbons even though they have smaller BET-surface. Carbon nanotubes reached the total removal efficiency over 86.8 % to be compared with removal efficiencies of only 70.0 and 54.2 % for the two other activated carbons tested. In addition, because of different adsorption mechanisms, the removal efficiencies of carbon nanotubes dropped more slowly with time than was the case for activated carbons. It could be attributed to the abundant mesopores distributed in the surface of carbon nanotubes. They enhanced the pore filled process of dioxin molecules during adsorption. In addition, strong interactions between the two benzene rings of dioxin molecules and the hexagonal arrays of carbon atoms in the surface make carbon nanotubes have bigger adsorption capacity.

Dynamic gene expression changes precede dioxin-induced liver pathogenesis in medaka fish.

PubMed

Volz, David C; Hinton, David E; Law, J McHugh; Kullman, Seth W

2006-02-01

A major challenge for environmental genomics is linking gene expression to cellular toxicity and morphological alteration. Herein, we address complexities related to hepatic gene expression responses after a single injection of the aryl hydrocarbon receptor (AHR) agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin) and illustrate an initial stress response followed by cytologic and adaptive changes in the teleost fish medaka. Using a custom 175-gene array, we find that overall hepatic gene expression and histological changes are strongly dependent on dose and time. The most pronounced dioxin-induced gene expression changes occurred early and preceded morphologic alteration in the liver. Following a systematic search for putative Ah response elements (AHREs) (5'-CACGCA-3') within 2000 bp upstream of the predicted transcriptional start site, the majority (87%) of genes screened in this study did not contain an AHRE, suggesting that gene expression was not solely dependent on AHRE-mediated transcription. Moreover, in the highest dosage, we observed gene expression changes associated with adaptation that persisted for almost two weeks, including induction of a gene putatively identified as ependymin that may function in hepatic injury repair. These data suggest that the cellular response to dioxin involves both AHRE- and non-AHRE-mediated transcription, and that coupling gene expression profiling with analysis of morphologic pathogenesis is essential for establishing temporal relationships between transcriptional changes, toxicity, and adaptation to hepatic injury.

Estimating implementation and operational costs of an integrated tiered CD4 service including laboratory and point of care testing in a remote health district in South Africa.

PubMed

Cassim, Naseem; Coetzee, Lindi M; Schnippel, Kathryn; Glencross, Deborah K

2014-01-01

An integrated tiered service delivery model (ITSDM) has been proposed to provide 'full-coverage' of CD4 services throughout South Africa. Five tiers are described, defined by testing volumes and number of referring health-facilities. These include: (1) Tier-1/decentralized point-of-care service (POC) in a single site; Tier-2/POC-hub servicing processing < 30-40 samples from 8-10 health-clinics; Tier-3/Community laboratories servicing ∼ 50 health-clinics, processing < 150 samples/day; high-volume centralized laboratories (Tier-4 and Tier-5) processing < 300 or > 600 samples/day and serving > 100 or > 200 health-clinics, respectively. The objective of this study was to establish costs of existing and ITSDM-tiers 1, 2 and 3 in a remote, under-serviced district in South Africa. Historical health-facility workload volumes from the Pixley-ka-Seme district, and the total volumes of CD4 tests performed by the adjacent district referral CD4 laboratories, linked to locations of all referring clinics and related laboratory-to-result turn-around time (LTR-TAT) data, were extracted from the NHLS Corporate-Data-Warehouse for the period April-2012 to March-2013. Tiers were costed separately (as a cost-per-result) including equipment, staffing, reagents and test consumable costs. A one-way sensitivity analyses provided for changes in reagent price, test volumes and personnel time. The lowest cost-per-result was noted for the existing laboratory-based Tiers- 4 and 5 ($6.24 and $5.37 respectively), but with related increased LTR-TAT of > 24-48 hours. Full service coverage with TAT < 6-hours could be achieved with placement of twenty-seven Tier-1/POC or eight Tier-2/POC-hubs, at a cost-per-result of $32.32 and $15.88 respectively. A single district Tier-3 laboratory also ensured 'full service coverage' and < 24 hour LTR-TAT for the district at $7.42 per-test. Implementing a single Tier-3/community laboratory to extend and improve delivery of services in Pixley-ka-Seme, with an estimated local ∼ 12-24-hour LTR-TAT, is ∼ $2 more than existing referred services per-test, but 2-4 fold cheaper than implementing eight Tier-2/POC-hubs or providing twenty-seven Tier-1/POCT CD4 services.

Background concentrations of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in the global oceanic atmosphere.

PubMed

Morales, Laura; Dachs, Jordi; González-Gaya, Belén; Hernán, Gema; Abalos, Manuela; Abad, Esteban

2014-09-02

The remote oceans are among the most pristine environments in the world, away from sources of anthropogenic persistent organic pollutants (POP), but nevertheless recipients of atmospheric deposition of POPs that have undergone long-range atmospheric transport (LRAT). In this work, the background occurrence of gas and aerosol phase polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin like polychlorinated biphenyls (dl-PCB) is evaluated for the first time in the atmosphere of the tropical and subtropical Atlantic, Pacific, and Indian oceans. Thirty-nine air samples were collected during the eight-month Malaspina circumnavigation cruise onboard the R/V Hespérides. The background levels of dioxins and dl-PCBs remained very low and in many cases very close to or below the limit of detection. Expectedly, the levels of PCBs were higher than dioxins, PCB#118 being the most abundant compound. In the particular case of dioxins, octachlorodibenzo-p-dioxin (OCDD) was the most abundant PCDD/F congener. Distribution of dl-PCB is dominated by the gas phase, while for PCDD/F the aerosol phase concentrations were higher, particularly for the more hydrophobic congeners. The Atlantic Ocean presented on average the highest PCDD/F and dl-PCB concentrations, being lower in the southern hemisphere. The assessment of air mass back trajectories show a clear influence of continental source regions, and lower concentrations when the air mass has an oceanic origin. In addition, the samples affected by an oceanic air mass are characterized by a lower contribution of the less chlorinated dioxins in comparison with the furans, consistent with the reported higher reaction rate constants of dibenzo-p-dioxins with OH radicals than those of dibenzofurans. The total dry atmospheric deposition of aerosol-bound ∑PCDD/F and ∑dl-PCB to the global oceans was estimated to be 354 and 896 kg/year, respectively.

Strain differences in the proteome of dioxin-sensitive and dioxin-resistant mice treated with 2,3,7,8-tetrabromodibenzo-p-dioxin.

PubMed

Nguyen, Hoa Thanh; Tsuchiya, Maria Claret Lauan; Yoo, Jean; Iida, Midori; Agusa, Tetsuro; Hirano, Masashi; Kim, Eun-Young; Miyazaki, Tatsuhiko; Nose, Masato; Iwata, Hisato

2017-04-01

Dioxins cause various toxic effects through the aryl hydrocarbon receptor (AHR) in vertebrates, with dramatic species and strain differences in susceptibility. Although inbred mouse strains C3H/HeJ-lpr/lpr (C3H/lpr) and MRL/MpJ-lpr/lpr (MRL/lpr) are known as dioxin-sensitive and dioxin-resistant mice, respectively, the molecular mechanism underlying this difference remains unclear. The difference in the hepatic proteome of the two mouse strains treated with vehicle or 2,3,7,8-tetrabromodibenzo-p-dioxin (TBDD) was investigated by a proteomic approach of two-dimensional electrophoresis (2-DE) coupled with matrix-assisted laser desorption/ionization time-of-flight/time-of-flight tandem mass spectrometry (MALDI-TOF/TOF). To confirm the strain-difference in response to TBDD treatment, cytochrome P450 (CYP) 1A1 and 1A2 protein levels were measured in both strains. A dose of 10 µg/kg body weight of TBDD induced hepatic CYP1A1 and CYP1A2 expression in both strains, but the expression levels of both CYP1A proteins were higher in C3H/lpr mice than in MRL/lpr mice, supporting that C3H/lpr mice are more sensitive to dioxins than MRL/lpr mice. Proteins that were more induced or suppressed by TBDD treatment in C3H/lpr mice were successfully identified by 2-DE and MALDI-TOF/TOF, including proteins responsible for AHR activation through production of endogenous ligands such as aspartate aminotransferase, indolethylamine N-methyltransferase, and aldehyde dehydrogenases, as well as proteins reducing oxidative stress, such as superoxide dismutase and peroxiredoxins. Taken together, our results provide insights into the molecular mechanism underlying the high dioxin susceptibility of the C3H/lpr strain, in which AHR activation by TBDD is more prompted by the production of endogenous ligands, but the adaptation to oxidative stress is also acquired.

Removal of dibenzofuran, dibenzo-p-dioxin, and 2-chlorodibenzo-p-dioxin from soils inoculated with Sphingomonas sp. strain RW1

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

Halden, R.U.; Halden, B.G.; Dwyer, D.F.

Removal of dibenzofuran, dibenzo-p-dioxin, and 2-chlorodibenzo-p-dioxin (2-CDD) (10 ppm each) from soil microcosms to final concentrations in the parts-per-billion range was affected by the addition of Sphingomonas sp. strain RW1. Rates and extents of removal were influenced by the density of RW1 organisms. For 2-CDD, the rate of removal was dependent on the content of soil organic matter (SOM), with half-life values ranging from 5.8 h (0% SOM) to 26.3 h (5.5% SOM).

Post-Vietnam military herbicide exposures in UC-123 Agent Orange spray aircraft.

PubMed

Lurker, Peter A; Berman, Fred; Clapp, Richard W; Stellman, Jeanne Mager

2014-04-01

During the Vietnam War, approximately 20 million gallons of herbicides, including ~10.5 million gallons of dioxin-contaminated Agent Orange, were sprayed by about 34 UC-123 aircraft that were subsequently returned to the United States, without decontamination or testing, to three Air Force reserve units for transport operations (~1971-1982). In 1996, observed dioxin contamination led to withdrawal of these UC-123s from public auction and to their smelting in 2009. Current Air Force and Department of Veterans Affairs policies stipulate that "dried residues" of chemical herbicides and dioxin had not lead to meaningful exposures to flight crew and maintenance personnel, who are thus ineligible for Agent Orange-related benefits or medical examinations and treatment. Sparse monitoring data are available for analysis. Three complementary approaches for modeling potential exposures to dioxin in the post-Vietnam war aircraft were employed: (1) using 1994 and 2009 Air Force surface wipe data to model personnel exposures and to estimate dioxin body burden for dermal-oral exposure for dried residues using modified generic US Environmental Protection Agency intake algorithms; (2) comparing 1979 Air Force 2,4- dichlorophenoxyacetic acid and 2,4-5-trichlorophenoxyacetic acid air samples to saturated vapor pressure concentrations to estimate potential dioxin exposure through inhalation, ingestion and skin contact with contaminated air and dust; and (3) applying emission models for semivolatile organic compounds from contaminated surfaces to estimate airborne contamination. Model (1): Body-burden estimates for dermal-oral exposure were 0.92 and 5.4pg/kg body-weight-day for flight crew and maintainers. The surface wipe concentrations were nearly two orders of magnitude greater than the US Army guidance level. Model (2): measured airborne concentrations were at least five times greater than saturated vapor pressure, yielding dioxin estimates that ranged from 13.2-27.0pg/m(3), thus supporting the likelihood of dioxin dust adsorption. Model (3): Theoretical models yielded consistent estimates to Model 2, 11-49pg/m(3), where the range reflects differences in experimental value of dioxin vapor pressure and surface area used. Model (3) results also support airborne contamination and dioxin dust adsorption. Inhalation, ingestion and skin absorption in aircrew and maintainers were likely to have occurred during post-Vietnam use of the aircraft based on the use of three complementary models. Measured and modeled values for dioxin exceeded several available guidelines. Deposition-aerosolization-redeposition homeostasis of semivolatile organic compound contaminants, particularly dioxin, is likely to have continually existed within the aircraft. Current Air Force and Department of Veterans Affairs policies are not consistent with the available industrial hygiene measurements or with the widely accepted models for semivolatile organic compounds. Copyright © 2014 Elsevier Inc. All rights reserved.

Do Students Know What They Know and What They Don't Know? Using a Four-Tier Diagnostic Test to Assess the Nature of Students' Alternative Conceptions

ERIC Educational Resources Information Center

Caleon, Imelda S.; Subramaniam, R.

2010-01-01

This study reports on the development and application of a four-tier multiple-choice (4TMC) diagnostic instrument, which has not been reported in the literature. It is an enhanced version of the two-tier multiple-choice (2TMC) test. As in 2TMC tests, its answer and reason tiers measure students' content knowledge and explanatory knowledge,…

A Tiered Model for Linking Students to the Community

ERIC Educational Resources Information Center

Meyer, Laura Landry; Gerard, Jean M.; Sturm, Michael R.; Wooldridge, Deborah G.

2016-01-01

A tiered practice model (introductory, pre-internship, and internship) embedded in the curriculum facilitates community engagement and creates relevance for students as they pursue a professional identity in Human Development and Family Studies. The tiered model integrates high-impact teaching practices (HIP) and student engagement pedagogies…

Residential proximity to industrial combustion facilities and risk of non-Hodgkin lymphoma: a case–control study

PubMed Central

2013-01-01

Background Residence near municipal solid waste incinerators, a major historical source of dioxin emissions, has been associated with increased risk of non-Hodgkin lymphoma (NHL) in European studies. The aim of our study was to evaluate residence near industrial combustion facilities and estimates of dioxin emissions in relation to NHL risk in the United States. Methods We conducted a population-based case–control study of NHL (1998–2000) in four National Cancer Institute-Surveillance Epidemiology and End Results centers (Detroit, Iowa, Los Angeles, Seattle). Residential histories 15 years before diagnosis (similar date for controls) were linked to an Environmental Protection Agency database of dioxin-emitting facilities for 969 cases and 749 controls. We evaluated proximity (3 and 5 km) to 10 facility types that accounted for >85% of U.S. emissions and a distance-weighted average emission index (AEI [ng toxic equivalency quotient (TEQ)/year]). Results Proximity to any dioxin-emitting facility was not associated with NHL risk (3 km OR = 1.0, 95% CI 0.8-1.3). Risk was elevated for residence near cement kilns (5 km OR = 1.7, 95% CI 0.8-3.3; 3 km OR = 3.8, 95% CI 1.1-14.0) and reduced for residence near municipal solid waste incinerators (5 km OR = 0.5, 95% CI 0.3-0.9; 3 km OR = 0.3, 95% CI 0.1-1.4). The AEI was not associated with risk of NHL overall. Risk for marginal zone lymphoma was increased for the highest versus lowest quartile (5 km OR = 2.6, 95% CI 1.0-6.8; 3 km OR = 3.0, 95% CI 1.1-8.3). Conclusions Overall, we found no association with residential exposure to dioxins and NHL risk. However, findings for high emissions and marginal zone lymphoma and for specific facility types and all NHL provide some evidence of an association and deserve future study. PMID:23433489

Maternal dietary exposure to dioxins and polychlorinated biphenyls (PCBs) is associated with language delay in 3year old Norwegian children.

PubMed

Caspersen, I H; Haugen, M; Schjølberg, S; Vejrup, K; Knutsen, H K; Brantsæter, A L; Meltzer, H M; Alexander, J; Magnus, P; Kvalem, H E

2016-05-01

Prenatal exposure to dioxins and PCBs is potentially harmful to the developing fetus and may increase the risk of delayed or impaired neurodevelopment. Several studies have reported negative associations between prenatal exposure to these compounds and aspects of cognition related to language in early childhood. The aim was to examine the association between maternal low level dietary exposure to dioxins and PCB during pregnancy and language development in 3year old children in a large group of mother-child pairs participating in the Norwegian Mother and Child Cohort Study (MoBa). This study includes 44,092 children of women who were recruited to the Norwegian Mother and Child Cohort Study (MoBa) during the years 2002-2009. Maternal dietary exposure to dioxins and PCBs was estimated based on a validated food frequency questionnaire (FFQ) answered mid-pregnancy and a database of dioxin and PCB concentrations in Norwegian foods. Exposure to dioxins and dioxin-like PCBs (dl-compounds) was expressed in total toxic equivalents (TEQ), and PCB-153 was used as marker for non-dioxin-like PCBs (ndlPCBs). Children's language skills at age 3 were assessed by parental report including a Dale and Bishop grammar rating and questions about communication skills from the Ages and Stages Questionnaire (ASQ). Logistic regression models adjusted for confounders were used to examine the association between maternal dietary exposure to dl-compounds or PCB-153 and language development in children. The maternal dietary exposure to dl-compounds and PCB-153 was generally low, and 98% of women had intakes of dl-compounds ≤14pg TEQ/kg bw/week, which is the tolerable weekly intake set by EU's Scientific Committee for Food (SCF). High maternal exposure (>14pg TEQ/kg bw/week of dl-compounds (median 2.6pg/kg bw/day, range 2-16) or >97.5-percentile intake of PCB-153 (median 11ng/kg bw/day, range 5-28) was associated with higher odds of incomplete grammar (in boys and girls, adjusted ORs 1.1 to 1.3) and severe language delay in girls, adjusted ORs 2.8 [95% CI 1.1, 7.1] for PCB-153 and 2.9 [95% CI 1.4, 5.9] for dl-compounds. Furthermore, high exposure to dl-compounds was associated with moderate language delay 1.4 [95% CI 1.0, 2.0] and lower communication score (ASQ), adjusted OR 1.4 [95% CI 1.1, 1.9] in girls. The main findings of this study were: 1) Girls born to mothers who exceeded the tolerable weekly intake for dl-compounds or had a PCB-153 intake above the 97.5 percentile in early pregnancy may have increased risk of language delay at age 3years. 2) Negative associations with maternal exposure to dl-compounds or PCB-153 were observed for both boys and girls having incomplete grammar, which is a subtle reduction in language skills. This interesting finding should not be considered as deviant at this age. Copyright © 2016 Elsevier Ltd. All rights reserved.

76 FR 40974 - Self-Regulatory Organizations; NYSE Arca, Inc.; Notice of Filing and Immediate Effectiveness of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-12

... Two New Pricing Tiers, Step-Up Tier 1 and Step-Up Tier 2 July 6, 2011. Pursuant to Section 19(b)(1) of... Services (the ``Schedule'') to introduce two new pricing tiers, Step-Up Tier 1 and Step-Up Tier 2. The text... Arca proposes to introduce two new pricing tier levels, Step-Up Tier 1 and Step-Up Tier 2. Step-Up Tier...

Tier-specific evolution of match performance characteristics in the English Premier League: it's getting tougher at the top.

PubMed

Bradley, Paul S; Archer, David T; Hogg, Bob; Schuth, Gabor; Bush, Michael; Carling, Chris; Barnes, Chris

2016-01-01

This study investigated the evolution of physical and technical performances in the English Premier League (EPL), with special reference to league ranking. Match performance observations (n = 14,700) were collected using a multiple-camera computerised tracking system across seven consecutive EPL seasons (2006-07 to 2012-13). Final league rankings were classified into Tiers: (A) 1st-4th ranking (n = 2519), (B) 5th-8th ranking (n = 2965), (C) 9th-14th ranking (n = 4448) and (D) 15th-20th ranking (n = 4768). Teams in Tier B demonstrated moderate increases in high-intensity running distance while in ball possession from the 2006-07 to 2012-13 season (P < 0.001; effect size [ES]: 0.68), with Tiers A, C and D producing less pronounced increases across the same period (P < 0.005; ES: 0.26, 0.41 and 0.33, respectively). Large increases in sprint distance were observed from the 2006-07 to 2012-13 season for Tier B (P < 0.001; ES: 1.21), while only moderate increases were evident for Tiers A, C and D (P < 0.001; ES: 0.75, 0.97 and 0.84, respectively). Tier B demonstrated large increases in the number of passes performed and received in 2012-13 compared to 2006-07 (P < 0.001; ES: 1.32-1.53) with small-to-moderate increases in Tier A (P < 0.001; ES: 0.30-0.38), Tier C (P < 0.001; ES: 0.46-0.54) and Tier D (P < 0.001; ES: 0.69-0.87). The demarcation line between 4th (bottom of Tier A) and 5th ranking (top of Tier B) in the 2006-07 season was 8 points, but this decreased to just a single point in the 2012-13 season. The data demonstrate that physical and technical performances have evolved more in Tier B than any other Tier in the EPL and could indicate a narrowing of the performance gap between the top two Tiers.

An Exploratory Study: Assessment of Modeled Dioxin ...

EPA Pesticide Factsheets

EPA has released an external review draft entitled, An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios(External Review Draft). The public comment period and the external peer-review workshop are separate processes that provide opportunities for all interested parties to comment on the document. In addition to consideration by EPA, all public comments submitted in accordance with this notice will also be forwarded to EPA’s contractor for the external peer-review panel prior to the workshop. EPA has realeased this draft document solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. This document has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency policy or determination. The purpose of this report is to describe an exploratory investigation of potential dioxin exposures to artists/hobbyists who use ball clay to make pottery and related products.

Evaluation of personal cooling devices for dioxin clean-up operation

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

Lawrence, W.T.; Goldman, R.F.

1988-09-07

The study investigated the use of personal coolers to increase worker productivity and safety while working at elevated, ambient temperatures cleaning up dioxin contaminated soil. The study included laboratory tests to measure the thermal characteristics of the chemical protective clothing worn and the performance of ice vest and vortex personal coolers. In addition, field tests were conducted at a dioxin clean-up site to evaluate the performance of these two types of personal coolers. The use of personal coolers was found to be an effective method of reducing the risk of heat stress. In addition, workers were able to work continuouslymore » in hot weather without following the procedure normally used to decrease heat stress, i.e., working one hour followed by one hour of resting. Both types of personal coolers were acceptable for the task being performed.« less

INHIBITION OF HUMAN AND RAT CYP1A2 BY TCDD AND DIOXIN-LIKE CHEMICALS

EPA Science Inventory

Dioxins have been shown to bind and induce rodent CYP1A2, producing a dose-dependent hepatic sequestration in vivo. The induction of CYP1A2 activity has been used as a noninvasive biomarker for human exposure to dioxins; while there is a consistent relationship between exposure ...

Method for immunodiagnostic detection of dioxins at low concentrations

DOEpatents

Vanderlaan, Martin; Stanker, Larry H.; Watkins, Bruce E.; Petrovic, Peter; Gorbach, Siegbert

1995-01-01

A method is described for the use of monoclonal antibodies in a sensitive immunoassay for halogenated dioxins and dibenzofurans in industrial samples which contain impurities. Appropriate sample preparation and selective enzyme amplification of the immunoassay sensitivity permits detection of dioxin contaminants in industrial or environmental samples at concentrations in the range of a few parts per trillion.

Exposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (Tcdd) and Related Compounds: Science Advisory Board (External Review Draft) (2000)

EPA Science Inventory

Dioxin Reassessment, SAB Review Draft

The U.S. Environmental Protection Agency's (EPA) is progressing toward completion of its comprehensive reassessment of dioxin science entitled, "Exposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibe...