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Sample records for tetrachlorodibenzodioxin

  1. Relationship between clinical and electrophysiological findings and indicators of heavy exposure to 2,3,7,8-tetrachlorodibenzo-dioxin

    Energy Technology Data Exchange (ETDEWEB)

    Filippini, G.; Bordo, B.; Crenna, P.; Massetto, N.; Musicco, M.; Boeri, R.

    1981-12-01

    In this study the prevalence rate of peripheral neuropathy in a population living in an area polluted with 2,3,7,8-tetrachlorodibenzo-dioxin (dioxin-TCDD) was determined. Of the 723 subjects invited to the first screening in 1977, 470 (65%) attended. At the second screening in 1978, of the 710 invited subjects, 319 (45%) attended. Prevalence rate ratios for peripheral neuropathy and the associated 95% confidence limits were calculated for subgroups determined by the presence of (i) predisposing factors to neuropathy (alcoholism, diabetes, occupational exposure to neurotoxic agents, etc) or (ii) conditions thought to result from exposure to dioxin-TCDD such as chloracne or abnormal serum hepatic enzyme levels. The prevalence rate of peripheral neuropathy among those subjects with predisposing factors and among those with chloracne or abnormal serum hepatic enzyme levels was nearly three times greater than among those without these manifestations. The results derived from this study may be useful qualitative pointers for identifying subjects at risk in the neurological follow-up.

  2. Simulating the Vapour Phase Air/Water Exchange of p,p′-DDE, p,p′-DDT, Lindane, and 2,3,7,8-Tetrachlorodibenzodioxin

    Science.gov (United States)

    Uncertainties in our understanding of gaseous air/water exchange have emerged as major sources of concern in efforts to construct global and regional mass balances of both the green house gas carbon dioxide and semi-volatile persistent, bioaccumulative and toxic chemicals. Hoff e...

  3. Synthesis of a Molecularly Imprinted Polymer for Dioxin

    Directory of Open Access Journals (Sweden)

    Magda Brattoli

    2006-08-01

    Full Text Available A molecularly imprinted polymer for recognising selectively 2,3,7,8-tetrachlorodibenzodioxin (TCDD was made by a new non-covalent method employing a“dummy” template. The proposed way represents a simplification of a synthetic schemeproposed by Lübke et al.[1] for covalent imprinting. Comparison of extraction yields of thenovel polymer, a non imprinted polymer and an imprinting polymer, prepared by theoriginal procedure demonstrates the binding capacity of the proposed polymer, which is inprinciple applicable to solid phase extraction (SPE of dioxin.

  4. Studies of the combustion of coal/refuse derived fuels using thermogravimetric-Fourier transform infrared-mass spectrometry

    International Nuclear Information System (INIS)

    Lu, Huagang; Li, Jigui; Lloyd, W.G.

    1995-01-01

    According to a report of the Environmental Protection Agency (EPA), 'Characterization of Municipal Solid Waste (MSW) in the United States', the total MSW produced in the U.S. increased from 179 million tons in 1988 to 195 million tons in 1990. The EPA predicted that the country would produce about 216 million tons of garbage in the year 2000. The amount of waste generated and the rapidly declining availability of sanitary landfills has forced most municipalities to evaluate alternative waste management technologies for reducing the volume of waste sent to landfills. The fraction of MSW that is processed by such technologies as separation and recycling, composting, and waste-to-energy was forecast to increase from a few percent today to 30-40% by the year 2000. Waste-to-energy conversion of MSW can appear to be attractive because of the energy recovered, the economic value of recycled materials, and the cost savings derived from reduced landfill usage. However, extra care needs to be taken in burning MSW or refuse-derived fuel (RDF) to optimize the operating conditions of a combustor so that the combustion takes place in an environmentally acceptable manner. For instance, polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) have been found in the precipitator fly ash and flue gas of some incinerator facilities in the United States and Europe. The amount of PCDDs and PCDFs occurs only in the parts-per-billion to parts-per-trillion range, but these chlorinated organics exhibit very high toxicity (LD 50 < 10 μg/Kg). The compound 2,3,7,8-tetrachlorodibenzodioxin has been found to be acnegenic, carcinogenic, and teratogenic. This has slowed or even stopped the construction and operation of waste-to-energy plants

  5. A Systems Biology Approach Reveals Converging Molecular Mechanisms that Link Different POPs to Common Metabolic Diseases.

    Science.gov (United States)

    Ruiz, Patricia; Perlina, Ally; Mumtaz, Moiz; Fowler, Bruce A

    2016-07-01

    A number of epidemiological studies have identified statistical associations between persistent organic pollutants (POPs) and metabolic diseases, but testable hypotheses regarding underlying molecular mechanisms to explain these linkages have not been published. We assessed the underlying mechanisms of POPs that have been associated with metabolic diseases; three well-known POPs [2,3,7,8-tetrachlorodibenzodioxin (TCDD), 2,2´,4,4´,5,5´-hexachlorobiphenyl (PCB 153), and 4,4´-dichlorodiphenyldichloroethylene (p,p´-DDE)] were studied. We used advanced database search tools to delineate testable hypotheses and to guide laboratory-based research studies into underlying mechanisms by which this POP mixture could produce or exacerbate metabolic diseases. For our searches, we used proprietary systems biology software (MetaCore™/MetaDrug™) to conduct advanced search queries for the underlying interactions database, followed by directional network construction to identify common mechanisms for these POPs within two or fewer interaction steps downstream of their primary targets. These common downstream pathways belong to various cytokine and chemokine families with experimentally well-documented causal associations with type 2 diabetes. Our systems biology approach allowed identification of converging pathways leading to activation of common downstream targets. To our knowledge, this is the first study to propose an integrated global set of step-by-step molecular mechanisms for a combination of three common POPs using a systems biology approach, which may link POP exposure to diseases. Experimental evaluation of the proposed pathways may lead to development of predictive biomarkers of the effects of POPs, which could translate into disease prevention and effective clinical treatment strategies. Ruiz P, Perlina A, Mumtaz M, Fowler BA. 2016. A systems biology approach reveals converging molecular mechanisms that link different POPs to common metabolic diseases. Environ

  6. Studies of the combustion of coal/refuse derived fuels using thermogravimetric-Fourier transform infrared-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Huagang; Li, Jigui; Lloyd, W.G.

    1995-11-01

    According to a report of the Environmental Protection Agency (EPA), `Characterization of Municipal Solid Waste (MSW) in the United States`, the total MSW produced in the U.S. increased from 179 million tons in 1988 to 195 million tons in 1990. The EPA predicted that the country would produce about 216 million tons of garbage in the year 2000. The amount of waste generated and the rapidly declining availability of sanitary landfills has forced most municipalities to evaluate alternative waste management technologies for reducing the volume of waste sent to landfills. The fraction of MSW that is processed by such technologies as separation and recycling, composting, and waste-to-energy was forecast to increase from a few percent today to 30-40% by the year 2000. Waste-to-energy conversion of MSW can appear to be attractive because of the energy recovered, the economic value of recycled materials, and the cost savings derived from reduced landfill usage. However, extra care needs to be taken in burning MSW or refuse-derived fuel (RDF) to optimize the operating conditions of a combustor so that the combustion takes place in an environmentally acceptable manner. For instance, polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) have been found in the precipitator fly ash and flue gas of some incinerator facilities in the United States and Europe. The amount of PCDDs and PCDFs occurs only in the parts-per-billion to parts-per-trillion range, but these chlorinated organics exhibit very high toxicity (LD{sub 50} < 10 {mu}g/Kg). The compound 2,3,7,8-tetrachlorodibenzodioxin has been found to be acnegenic, carcinogenic, and teratogenic. This has slowed or even stopped the construction and operation of waste-to-energy plants.

  7. Transcriptional responses of metallothionein gene to different stress factors in Pacific abalone (Haliotis discus hannai).

    Science.gov (United States)

    Lee, Sang Yoon; Nam, Yoon Kwon

    2016-11-01

    A novel metallothionein (MT) gene from the Pacific abalone H. discus hannai was characterized and its mRNA expression patterns (tissue distribution, developmental expression and differential expression in responsive to various in vivo stimulatory treatments) were examined. Abalone MT shares conserved structural features with previously known gastropod orthologs at both genomic (i.e., tripartite organization) and amino acid (conserved Cys motifs) levels. The 5'-flanking regulatory region of abalone MT gene displayed various transcription factor binding motifs particularly including ones related with metal regulation and stress/immune responses. Tissue distribution and basal expression patterns of MT mRNAs indicated a potential association between ovarian MT expression and sexual maturation. Developmental expression pattern suggested the maternal contribution of MT mRNAs to embryonic and early larval developments. Abalone MT mRNAs could be significantly induced by various heavy metals in different tissues (gill, hepatopancreas, muscle and hemocyte) in a tissue- and/or metal-dependent fashion. In addition, the abalone MT gene was highly modulated in responsive to other non-metal, stimulatory treatments such as immune challenge (LPS, polyI:C and bacterial injections), hypoxia (decrease from normoxia 8 ppm-2 ppm), thermal elevation (increase from 20 °C to 30 °C), and xenobiotic exposure (250 ppb of 17α-ethynylestradiol and 0.25 ppb of 2,3,7,8-tetrachlorodibenzodioxin) where differential expression patterns were toward either up- or down-regulation depending on types of stimulations and tissues examined. Taken together, our results highlight that MT is a multifunctional effector playing in wide criteria of cellular pathways especially associated with development and stress responses in this abalone species. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Toxicogenomic responses in rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals and a synthetic mixture

    International Nuclear Information System (INIS)

    Finne, E.F.; Cooper, G.A.; Koop, B.F.; Hylland, K.; Tollefsen, K.E.

    2007-01-01

    As more salmon gene expression data has become available, the cDNA microarray platform has emerged as an appealing alternative in ecotoxicological screening of single chemicals and environmental samples relevant to the aquatic environment. This study was performed to validate biomarker gene responses of in vitro cultured rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals, and to investigate effects of mixture toxicity in a synthetic mixture. Chemicals used for 24 h single chemical- and mixture exposures were 10 nM 17α-ethinylestradiol (EE2), 0.75 nM 2,3,7,8-tetrachloro-di-benzodioxin (TCDD), 100 μM paraquat (PQ) and 0.75 μM 4-nitroquinoline-1-oxide (NQO). RNA was isolated from exposed cells, DNAse treated and quality controlled before cDNA synthesis, fluorescent labelling and hybridisation to a 16k salmonid microarray. The salmonid 16k cDNA array identified differential gene expression predictive of exposure, which could be verified by quantitative real time PCR. More precisely, the responses of biomarker genes such as cytochrome p4501A and UDP-glucuronosyl transferase to TCDD exposure, glutathione reductase and gammaglutamyl cysteine synthetase to paraquat exposure, as well as vitellogenin and vitelline envelope protein to EE2 exposure validated the use of microarray applied to RNA extracted from in vitro exposed hepatocytes. The mutagenic compound NQO did not result in any change in gene expression. Results from exposure to a synthetic mixture of the same four chemicals, using identical concentrations as for single chemical exposures, revealed combined effects that were not predicted by results for individual chemicals alone. In general, the response of exposure to this mixture led to an average loss of approximately 60% of the transcriptomic signature found for single chemical exposure. The present findings show that microarray analyses may contribute to our mechanistic understanding of single contaminant mode of action as well as

  9. Consumption patterns and risk assessment of crab consumers from the Newark Bay Complex, New Jersey, USA.

    Science.gov (United States)

    Pflugh, Kerry Kirk; Stern, Alan H; Nesposudny, Laura; Lurig, Lynette; Ruppel, Bruce; Buchanan, Gary A

    2011-10-01

    The Newark Bay Complex (NBC) is a significant historical repository of polychlorinated dibenzodioxins (PCDDs) and dioxin-like compounds. Detection of high levels of 2,3,7,8 tetrachloro-dibenzodioxins (TCDD) and its toxicological equivalents in blue crabs in the early 1990's led to a ban on the taking and distribution of crabs from the NBC. Despite this ban and ongoing communication outreach, surveys of crabbers in 1995, 2002 and 2005 by the New Jersey Department of Environmental Protection (NJDEP) showed that crabbing for recreational purposes and for significant dietary supplementation was continuing. At the time they were surveyed, the crabbers had been consuming these crabs for an average of 37% of their lives. Thus, exposure can be considered chronic. The surveys provided data on the duration, frequency and amount of NBC crab consumption. In 2004, the NJDEP sampled blue crabs in the NBC and analyzed the edible portions for 2,3,7,8 TCDD toxicity equivalent (TEQ) concentration. We have combined the survey-based exposure data and the 2,3,7,8 TCDD TEQ concentration data to produce an estimate of the lifetime cancer risk to NBC crabbers from dioxin-like compounds. We employed a point-estimate approach using discrete lower, central tendency and reasonable maximum exposure (RME) estimates of exposure factors and a probabilistic approach to exposure factors. Both approaches show central tendency lifetime cancer risk of greater than one-in-a-thousand (10(-3)) and an upper percentile/RME risk of approximately one-in-a-hundred (10(-2)). Little extrapolation is involved in applying the 2,3,7,8-TCDD TEQ concentration data in crabs to risk estimates in the population consuming those crabs. The ongoing and frequent nature of the crab collection minimizes the uncertainty often inherent in food recall surveys. These estimates point to the continued risk posed to NBC crab consumers and to the continuing importance of this resource which, with proper remediation, could provide

  10. Toxicogenomic responses in rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals and a synthetic mixture

    Energy Technology Data Exchange (ETDEWEB)

    Finne, E.F. [Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo (Norway) and University of Oslo, Department of Biology, P.O. Box 1066, Blindern, N-0316 Oslo (Norway)]. E-mail: eivind.finne@niva.no; Cooper, G.A. [Centre for Biomedical Research, University of Victoria, BC V8P5C2 (Canada); Koop, B.F. [Centre for Biomedical Research, University of Victoria, BC V8P5C2 (Canada); Hylland, K. [Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo (Norway); University of Oslo, Department of Biology, P.O. Box 1066, Blindern, N-0316 Oslo (Norway); Tollefsen, K.E. [Norwegian Institute for Water Research, Gaustadalleen 21, N-0349 Oslo (Norway)

    2007-03-10

    As more salmon gene expression data has become available, the cDNA microarray platform has emerged as an appealing alternative in ecotoxicological screening of single chemicals and environmental samples relevant to the aquatic environment. This study was performed to validate biomarker gene responses of in vitro cultured rainbow trout (Oncorhynchus mykiss) hepatocytes exposed to model chemicals, and to investigate effects of mixture toxicity in a synthetic mixture. Chemicals used for 24 h single chemical- and mixture exposures were 10 nM 17{alpha}-ethinylestradiol (EE2), 0.75 nM 2,3,7,8-tetrachloro-di-benzodioxin (TCDD), 100 {mu}M paraquat (PQ) and 0.75 {mu}M 4-nitroquinoline-1-oxide (NQO). RNA was isolated from exposed cells, DNAse treated and quality controlled before cDNA synthesis, fluorescent labelling and hybridisation to a 16k salmonid microarray. The salmonid 16k cDNA array identified differential gene expression predictive of exposure, which could be verified by quantitative real time PCR. More precisely, the responses of biomarker genes such as cytochrome p4501A and UDP-glucuronosyl transferase to TCDD exposure, glutathione reductase and gammaglutamyl cysteine synthetase to paraquat exposure, as well as vitellogenin and vitelline envelope protein to EE2 exposure validated the use of microarray applied to RNA extracted from in vitro exposed hepatocytes. The mutagenic compound NQO did not result in any change in gene expression. Results from exposure to a synthetic mixture of the same four chemicals, using identical concentrations as for single chemical exposures, revealed combined effects that were not predicted by results for individual chemicals alone. In general, the response of exposure to this mixture led to an average loss of approximately 60% of the transcriptomic signature found for single chemical exposure. The present findings show that microarray analyses may contribute to our mechanistic understanding of single contaminant mode of action as