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Ecotoxicology 2020 May 14;29(4):493-502. Epub 2020 Apr 14.

Facultad de Ciencias, Universidad Autónoma de Baja California, Carretera Transpeninsular Tijuana-Ensenada No. 3917, Fraccionamiento Playitas, CP 22860, Ensenada, Baja California, Mexico.

The environmental exposure to As, Se, Hg, Pb, Cr and toxaphene was assessed for 11 freshwater fish species in irrigation channels, agricultural return flow drains, a drain collecting lagoon and sections of the Colorado River at the Mexicali valley in Baja California, México, during August 2015-April 2016. Arsenic (2.90 ng ml) and Se (1. Read More

Mol Cell Endocrinol 2020 May 26;507:110764. Epub 2020 Feb 26.

Department of Physiological Sciences, Center for Environmental and Human Toxicology, UF, USA; Genetics Institute, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611, USA. Electronic address:

Organochlorine pesticides (OCPs) are persistent environmental contaminants that act as endocrine disruptors and organ system toxicants. These pesticides (e.g. Read More

Comp Biochem Physiol C Toxicol Pharmacol 2020 Feb 9;228:108669. Epub 2019 Nov 9.

Department of Physiological Sciences and Center for Environmental and Human Toxicology, UF Genetics Institute, College of Veterinary Medicine, University of Florida, Gainesville, FL 32611, USA. Electronic address:

Toxaphene is a restricted-use pesticide produced by reacting chlorine gas with camphene. It was heavily used as a pesticide for agricultural purposes in the 1960-1970s, but despite being banned >30 years ago, it can remain elevated in the soil due to its resistance to metabolic degradation; this has led to longstanding concerns about elevated levels of toxaphene and other organochlorine pesticides (OCPs) in the environment. The objective of this study were to determine the effects of waterborne exposure to toxaphene on early life stages of zebrafish. Read More

Chemosphere 2018 May 3;198:432-441. Epub 2018 Feb 3.

Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Tuwima Street 10, 10-748 Olsztyn, Poland.

We examined the direct effects of toxaphene and endrin, chlorinated insecticides that are widespread in the environment, on myometrial contractions and on the secretion of hormones involved in regulating these contractions. Granulosa, luteal, endometrial and myometrial cells, and myometrial strips from non-pregnant cows were incubated with both insecticides at environmentally relevant doses. Toxaphene inhibited and endrin stimulated the secretion of testosterone and oestradiol from granulosa cells. Read More

Environ Health 2017 09 6;16(1):95. Epub 2017 Sep 6.

Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.

Background: Organochlorine insecticides (OCs) have historically been used worldwide to control insects, although most have now been banned in developed countries. Evidence for an association between OC exposures and cancer predominantly comes from occupational and population based-studies among men. We evaluated the association between the use of specific OCs and cancer among the female spouses of pesticide applicators in the Agricultural Health Study. Read More

Environ Health Perspect 2017 07 14;125(7):077010. Epub 2017 Jul 14.

Epidemiology Branch, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA

Background: The occupation of farming has been associated with rheumatoid arthritis (RA); pesticides may account for this association, but there are few studies.

Objectives: We investigated associations between RA and use of pesticides in the Agricultural Health Study.

Methods: The study sample was drawn from male pesticide applicators enrolled in 1993–1997 who provided questionnaire data at baseline and at least once during follow-up (over a median 18 y; interquartile range 16–19). Read More

J Appl Toxicol 2017 08 20;37(8):967-975. Epub 2017 Feb 20.

Department of Environmental Health, Indiana University Bloomington, IN, 47405, USA.

Toxaphene was shown to increase liver tumor incidence in B6C3F1 mice following chronic dietary exposure. Preliminary evidence supported a role for the constitutive androstane receptor (CAR) in the mode of action of toxaphene-induced mouse liver tumors. However, these results could not rule out a role for the pregnane X receptor (PXR) in liver tumor formation. Read More

Environ Health Perspect 2017 04 4;125(4):586-593. Epub 2016 Oct 4.

Department of Physical & Environmental Sciences, University of Toronto, Toronto, Ontario, Canada.

Background: The North American Great Lakes are home to > 140 types of fish and are famous for recreational and commercial fishing. However, the presence of toxic substances has resulted in the issuance of fish consumption advisories that are typically based on the most restrictive contaminant.

Objectives: We investigated whether these advisories, which typically neglect the existence of a mixture of chemicals and their possible additive adverse effects, are adequately protective of the health of humans consuming fish from the Canadian waters of the Great Lakes. Read More

Toxicol Sci 2015 Oct 16;147(2):549-61. Epub 2015 Jul 16.

*Department of Environmental Health, Indiana University Bloomington, Indiana 47405; and

Chronic exposure to toxaphene resulted in an increase in liver tumors in B6C3F1 mice. This study was performed to investigate the mode of action of toxaphene induced mouse liver tumors. Following an initial 14 day dietary dose range-finding study in male mice, a mechanistic study (0, 3, 32, and 320 ppm toxaphene in diet for 7, 14, and 28 days of treatment) was performed to examine the potential mechanisms of toxaphene induced mouse liver tumors. Read More

J Environ Manage 2015 Sep 12;160:16-29. Epub 2015 Jun 12.

Case Western Reserve University, Department of Civil Engineering, 10900 Euclid Ave., Cleveland OH 44106-7201, USA. Electronic address:

Surface soil contamination is a worldwide problem. Many regulatory jurisdictions attempt to control human exposures with regulatory guidance values (RGVs) that specify a soil's maximum allowable concentration. Pesticides are important soil contaminants because of their intentional toxicity and widespread surface soil application. Read More

Pestic Biochem Physiol 2015 May 14;120:64-7. Epub 2014 Nov 14.

Department of Environmental Toxicology, University of California, One Shields Avenue, Davis, CA 95616, USA. Electronic address:

Fumio Matsumura joined the University of California, Davis, faculty in 1987 where he served as founding director of the Center for Environmental Health Sciences, associate director of the U.C. Toxic Substances Research and Teaching Program, and chair of the Department of Environmental Toxicology. Read More

Rev Environ Contam Toxicol 2015 ;235:49-168

, 11693 Phelps Hill Road, Nevada City, CA, 95959, USA,

Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2014 7;31(5):872-88. Epub 2014 Apr 7.

a Staff Direction for Risk Assessment, Administration of Control Policy , Federal Agency for the Safety of the Food Chain , Brussels , Belgium.

This paper focuses on the risks of environmental carcinogenic and/or genotoxic contaminants in food. It describes, for each contaminant studied, the carcinogenicity and genotoxicity, the toxicological reference values, the exposure and the risk characterisation. The compounds studied were classified into 3 categories based on a risk assessment. Read More

PLoS One 2013 18;8(11):e81253. Epub 2013 Nov 18.

Department of Nutritional Science and Toxicology, University of California, Berkeley, Berkeley, California, United States of America.

Exposure to toxaphene, an environmentally persistent mixture of chlorinated terpenes previously utilized as an insecticide, has been associated with various cancers and diseases such as amyotrophic lateral sclerosis. Nevertheless, the cellular and molecular mechanisms responsible for these toxic effects have not been established. In this study, we used a functional approach in the model eukaryote Saccharomyces cerevisiae to demonstrate that toxaphene affects yeast mutants defective in (1) processes associated with transcription elongation and (2) nutrient utilization. Read More

Environ Toxicol Chem 2013 Dec 10;32(12):2663-71. Epub 2013 Oct 10.

Department of Plants, Soils, and Climate, Utah State University, Logan, Utah, USA.

Technical toxaphene, a broad-spectrum pesticide mixture, degrades in the environment, resulting in potential changes in toxicity. The present study uses a multimedia model that the authors developed to estimate toxaphene degradation in the atmosphere over North America. The predicted degradation has strong spatial and temporal variability determined by processes such as emission and transport of technical toxaphene, as well as the complex interactions among many species (e. Read More

Environ Health Perspect 2013 Aug 7;121(8):919-24. Epub 2013 Jun 7.

Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.

Background: Telomere length (TL) in surrogate tissues may be influenced by environmental exposures.

Objective: We aimed to determine whether lifetime pesticides use is associated with buccal cell TL.

Methods: We examined buccal cell TL in relation to lifetime use of 48 pesticides for 1,234 cancer-free white male pesticide applicators in the Agricultural Health Study (AHS), a prospective cohort study of 57,310 licensed pesticide applicators. Read More

Environ Sci Technol 2012 Dec 21;46(23):12882-9. Epub 2012 Nov 21.

Department of Pathology, College of Medicine and Functional RNomics Research Center, The Catholic University of Korea, Seoul, South Korea.

Persistent organic pollutants (POPs) are degradation-resistant anthropogenic chemicals that accumulate in the food chain and in adipose tissue, and are among the most hazardous compounds ever synthesized. However, their toxic mechanisms are still undefined. To investigate whether characteristic molecular signatures can discriminate individual POP and provide prediction markers for the early detection of POPs exposure in an animal model, we performed transcriptomic analysis of rat liver tissues after exposure to POPs. Read More

Comp Biochem Physiol C Toxicol Pharmacol 2012 Jun 1;156(1):37-41. Epub 2012 Apr 1.

South Sea Environment Research Department, Korea Ocean Research and Development Institute, Geoje, Republic of Korea.

We evaluated toxaphene-induced acute toxicity in Hydra magnipapillata. The median lethal concentrations of the animals (LC(50)) were determined to be 34.5 mg/L, 25. Read More

Integr Environ Assess Manag 2012 Jul 13;8(3):523-9. Epub 2012 Mar 13.

Institute for Environmental Studies, VU University, Amsterdam, The Netherlands.

A revised risk assessment for toxaphene was developed, based on the assumption that fish consumers are only exposed to toxaphene residues that differ substantially from technical toxaphene due to environmental degradation and metabolism. In vitro studies confirmed that both technical toxaphene and degraded toxaphene inhibit gap junctional intercellular communication that correlates with the mechanistic potential to cause tumor promotion. In vivo rat studies established the NOAEL for degraded and technical toxaphene at the highest dose tested in the bioassay. Read More

Rep Carcinog 2011 ;12:418-20

Ecotoxicology 2011 Oct 12;20(7):1588-98. Epub 2011 Jul 12.

Environmental Monitoring and Reporting Branch, Ontario Ministry of the Environment, Toronto, ON, Canada.

The majority of the restrictive fish consumption advisories for the Canadian waters of the Great Lakes issued by the Ontario Ministry of the Environment, Canada based on the most restrictive contaminant, are attributed to polychlorinated biphenyls (PCBs) and dioxins/furans. Mercury currently causes about <1-2.5% and 9-16% of the restrictive advisories for the general population (GP) and sensitive population of children under 15 and women of child-bearing age (SP), respectively (the St. Read More

J Biomed Nanotechnol 2011 Feb;7(1):172-4

Eco-Auditing Laboratory, National Botanical Research Institute (CSIR), Lucknow 226001, India.

Organochlorine pesticides (OCPs; aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, mirex, toxaphene and hexachlorocyclohexane) are chemical pollutants found in all environmental media. There is an urgent need to stop the usage and develop innovative strategies for the remediation of contaminated soil and water. The present work was aimed to evaluate the (i) interaction of fullerene with lindane and its role in the remediation of lindane from contaminated systems and (ii) compare the interaction of fullerene with lindane and trichloroethylene. Read More

Comp Biochem Physiol C Toxicol Pharmacol 2011 Apr 8;153(3):355-61. Epub 2011 Jan 8.

South Sea Environment Research Department, Korea Ocean Research and Development Institute, Geoje 656-830, Republic of Korea.

Differential gene expression profiles were established from the head and liver tissues of the marine medaka fish (Oryzias javanicus) after its exposure to toxaphene, a persistent organic pollutant and insecticide, using differential display polymerase chain reaction. Twenty-seven differentially expressed genes were identified, which were associated with the cytoskeleton, development, metabolism, nucleic acid/protein binding, and signal transduction. Among these genes, those encoding molecular biomarkers known to be involved in metabolism, ATP hydrolysis, and protein regulation were strongly induced at the transcription level, and genes encoding one structural protein subunit or involved in lipid metabolism were strongly downregulated. Read More

Int J Environ Res Public Health 2010 10 12;7(10):3615-27. Epub 2010 Oct 12.

Graduate Institute of Bioresources, National Pingtung University of Science and Technology, Pingtung 912, Taiwan.

Organochlorine pesticides (OCPs) are capable of persisting in the environment, transporting between phase media and accumulating to high levels, implying that they could pose a risk of causing adverse effects to human health and the environment. Consequently, most OCPs are designated as persistent organic pollutants (POPs) and even as endocrine disrupting chemicals (EDCs). The objective of this paper was to review the current status of pesticide POPs in Taiwan, including aldrin, chlordane, chlordecone, DDT, dieldrin, endrin, heptachlor, hexachlorobenzene, α/β-hexachlorocyclohexanes, lindane, mirex, pentachloro-benzene, and toxaphene. Read More

J Appl Toxicol 2011 Mar;31(2):108-16

Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA.

Microarrays enable gene transcript expression changes in near-whole genomes to be assessed in response to environmental stimuli. We utilized oligonucleotide microarrays and subsequent gene set enrichment analysis (GSEA) to assess patterns of gene expression changes in male largemouth bass (Micropterus salmoides) hepatic tissues after a 96 h exposure to common environmental contaminants. Fish were exposed to atrazine, cadmium chloride, PCB 126, phenanthrene and toxaphene via intraperitoneal injection with target body burdens of 3. Read More

Aquat Toxicol 2009 Oct 21;95(1):1-9. Epub 2009 Jun 21.

Department of Physiological Sciences and Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL 32611, USA.

Many aquatic contaminants potentially affect the central nervous system, however the underlying mechanisms of how toxicants alter normal brain function are not well understood. The objectives of this study were to compare the effects of emerging and prevalent environmental contaminants on the expression of brain transcripts with a role in neurotransmitter synthesis and reproduction. Adult male largemouth bass (Micropterus salmoides) were injected once for a 96 h duration with control (water or oil) or with one of two doses of a single chemical to achieve the following body burdens (microg/g): atrazine (0. Read More

Aquat Toxicol 2009 Oct 13;95(1):52-9. Epub 2009 Aug 13.

Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA.

Liver proteome response of largemouth bass (Micropterus salmoides) exposed to environmental contaminants was analyzed to identify novel biomarkers of exposure. Adult male bass were exposed to cadmium chloride (CdCl(2)), atrazine, PCB 126, phenanthrene, or toxaphene via intraperitoneal injection with target body burdens of 0.00067, 3. Read More

Environ Toxicol Chem 2009 Jul 9;28(7):1390-9. Epub 2009 Feb 9.

Marine Sciences Department, Savannah State University, Savannah, Georgia 31404, USA.

Although the Turtle/Brunswick River Estuary (TBRE) in coastal Georgia (USA) is severely contaminated by persistent organochlorine pollutants (POPs), little information regarding POPs in higher-trophic-level biota in this system is available. In the present study, polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs; including DDTs, chlordanes, and mirex), and chlorinated monoterpenes (toxaphene) were measured using gas chromatography with electron-capture detection and gas chromatography with electron-capture negative ion mass spectrometry (GC-ECNI-MS) in blubber of free-ranging and stranded bottlenose dolphins (Tursiops truncatus). Mean total PCBs (78. Read More

Arch Environ Contam Toxicol 2009 Aug 27;57(2):387-96. Epub 2008 Dec 27.

Caesar Kleberg Wildlife Research Institute, Texas A&M University-Kingsville, 700 University Boulevard, MSC 218, Kingsville, TX 78363, USA.

Our study determined if white-winged doves (WWDs; Zenaida asiatica asiatica) breeding in locations where environmentally persistent contaminants occur in the Lower Rio Grande Valley of Texas have levels of contaminants that can hinder reproduction. During summer 2003, 70 (32 males, 38 females) adult WWDs were collected from 8 at-risk sites. Liver tissues were analyzed for ten major and trace elements and muscle tissues were analyzed for 20 organochlorine compounds, 21 polychlorinated biphenyl congeners, and toxaphene. Read More

Rev Environ Contam Toxicol 2008 ;196:1-51

Pesticide Chemistry Department, National Research Centre Tahir Str., Dokki Cairo, Egypt.

The first use of petroleum-derived pesticides in Egyptian agriculture was initiated in 1950. Early applications consisted of distributing insecticidal dusts containing DDT/BHC/S onto cotton fields. This practice was followed by use of toxaphene until 1961. Read More

Crit Rev Toxicol 2008 ;38(9):805-15

The Weinberg Group, Washington, DC, USA.

Technical toxaphene (TT) was last used in commerce in about 1982. Any environmental exposure to toxaphene in this century is to environmentally degraded forms of toxaphene, termed weathered toxaphene. Several hundred chlorinated bornane congeners have been identified in technical toxaphene. Read More

Environ Pollut 2009 Feb 11;157(2):582-91. Epub 2008 Oct 11.

U.S. Geological Survey (USGS), Columbia Environmental Research Center (CERC), 4200 New Haven Road, Columbia, MO 65201, USA.

Organochlorine pesticide and total polychlorinated biphenyl (PCB) concentrations were measured in largemouth bass from the Tombigbee River near a former DDT manufacturing facility at McIntosh, Alabama. Evaluation of mean p,p'- and o,p'-DDT isomer concentrations and o,p'- versus p,p'-isomer proportions in McIntosh bass indicated that DDT is moving off site from the facility and into the Tombigbee River. Concentrations of p,p'-DDT isomers in McIntosh bass remained unchanged from 1974 to 2004 and were four times greater than contemporary concentrations from a national program. Read More

Ecotoxicology 2009 Jan 1;18(1):15-21. Epub 2008 Aug 1.

Department of Wildlife and Fisheries Sciences, Texas A&M University, 2258 TAMU, College Station, TX 77843-2258, USA.

Cliff swallows (Petrochelidon pyrrhonota) and cave swallows (P. fulva) were sampled during the breeding season at several locations in the Rio Grande, Texas, to evaluate the potential effects of environmental contaminants on P450 aromatase activity in brain and gonads and DNA damage in blood cells. The tritiated water-release aromatase assay was used to measure aromatase activity and flow cytometry was used to measure DNA damage in nucleated blood cells. Read More

Environ Monit Assess 2009 May 2;152(1-4):469-94. Epub 2008 Jul 2.

U.S. Geological Survey, Columbia Environmental Research Center, 4200 New Haven Rd., Columbia, MO 65201, USA.

Organochlorine chemical residues and elemental concentrations were measured in piscivorous and benthivorous fish at 111 sites from large U.S. river basins. Read More

Food Chem Toxicol 2008 Aug 10;46(8):2629-38. Epub 2008 May 10.

BioDetection Systems BV, Kruislaan 406, 1098 SM, Amsterdam, The Netherlands.

In this study the potential impact of food chain-based biotransformation and physico-chemical weathering of toxaphene on its tumour promoting potential was investigated in vitro and in vivo. Human exposure to toxaphene is mainly through consumption of contaminated fish, therefore fish-borne residues of toxaphene (cod liver extract, CLE) were prepared by exposing cod to technical toxaphene (TT) for 63 days. UV-irradiated toxaphene (uvT) was included to represent a physico-chemical weathered toxaphene mixture. Read More

Ecotoxicol Environ Saf 2009 Jan 27;72(1):162-172. Epub 2008 May 27.

Southern California Coastal Water Research Project, Westminster, CA 92683, USA.

A test program was conducted to evaluate the mutagenicity of toxaphene residuals extracted from aged soils and from fish collected in creeks near a toxaphene-contaminated site. The ultimate objective was to determine if the residual toxaphene congeners were more or less mutagenic than those in technical-grade toxaphene. The study showed that the mutagenicity of the bioaccumulated toxaphene congeners in fish, expressed as colony revertants per microg of residual toxaphene, was no greater than that of technical-grade toxaphene. Read More

Food Chem Toxicol 2008 Jul 16;46(7):2320-5. Epub 2008 Mar 16.

Technical University of Munich, Department for Chemical-Technical Analysis and Chemical Food Technology, Research Center Weihenstephan for Brewing and Food Technology, Weihenstephaner Steig 23, D-85354 Freising-Weihenstephan, Germany.

Toxaphene is a chlorinated pesticide consisting of more than 200 congeners that are mainly chlorobornanes and chlorocamphenes. As the congeners exhibit different stability properties in the environment, only between 20 and 30 compounds can be observed in, e.g. Read More

Ecotoxicol Environ Saf 2007 Nov 26;68(3):326-34. Epub 2007 Jun 26.

RECETOX-Research Centre for Environmental Chemistry and Ecotoxicology, Faculty of Science, Masaryk University, Kamenice 126/3, CZ-625 00 Brno, Czech Republic.

The polychlorinated insecticide toxaphene belonged to the most used pesticides in the 20th century. Even recently, significant residues have been found in soils at various sites in the world. However, knowledge on toxicity to soil organisms is limited. Read More

Environ Int 2007 Aug 20;33(6):798-804. Epub 2007 Apr 20.

RECETOX - Research Centre for Environmental Chemistry and Ecotoxicology, Masaryk University Brno, Kamenice 126/3, Brno, CZ-625 00, Czech Republic.

Caenorhabditis elegans is a free-living soil nematode that is commonly used as a model for toxicity tests. The aim of this study was to investigate the toxicity of seven organic pollutants: four azaarenes (quinoline, acridine, phenazine, and 1,10-phenanthroline), short-chain chlorinated paraffins, and two organochlorinated pesticides (toxaphene and hexachlorobenzene). The exposure to all chemicals was carried out in three test media (soil, agar, and aquatic medium), and adult mortality was evaluated after 24 and 48 h. Read More

Sci Total Environ 2007 Jun 5;378(3):376-402. Epub 2007 Apr 5.

U.S. Geological Survey (USGS), Columbia Environmental Research Center (CERC), Columbia, MO 65201, USA.

Common carp (Cyprinus carpio), black bass (Micropterus spp.), and channel catfish (Ictalurus punctatus) were collected from 14 sites in the Colorado River Basin (CRB) to document spatial trends in accumulative contaminants, health indicators, and reproductive biomarkers. Organochlorine residues, 2,3,7,8-tetrachlorodibenzo-p-dioxin-like activity (TCDD-EQ), and elemental contaminants were measured in composite samples of whole fish, grouped by species and gender, from each site. Read More

Arch Environ Contam Toxicol 2007 May 29;52(4):549-62. Epub 2007 Mar 29.

Columbia Environmental Research Center, United States Geological Survey, Columbia, MO 65201, USA.

As part of a larger investigation, northern pike (n = 158; Esox lucius) were collected from ten sites in the Yukon River Basin (YRB), Alaska, to document biomarkers and their correlations with organochlorine pesticide (total p,p'-DDT, total chlordane, dieldrin, and toxaphene), total polychlorinated biphenyls (PCBs), and elemental contaminant (arsenic, cadmium, copper, lead, total mercury, selenium, and zinc) concentrations. A suite of biomarkers including somatic indices, hepatic 7-ethoxyresorufin O-deethylase (EROD) activity, vitellogenin concentrations, steroid hormone (17B- ustradiol and 16-kebtestosteront) concentrations, splenic macrophage aggregates (MAs), oocyte atresia, and other microscopic anomalies in various tissues were documented in YRB pike. Mean condition factor (0. Read More

Jpn J Vet Res 2006 Nov;54(2-3):119-28

School of Veterinary Medicine, University of Zambia, Box 32379, Lusaka, Zambia.

The study determined the types of pesticide/herbicide pollutants in water, sediment and fish from the Kafue River. A preliminary investigation of the oxidative stress from these pesticides/herbicides was also assessed by measurement of catalase activity. Water, sediment and fish samples were collected upstream, midstream and downstream the Kafue river in Chingola, Kitwe, Kafue National Park and Kafue Town. Read More

Environ Toxicol Chem 2006 Nov;25(11):2884-9

University of Hohenheim, Institute of Food Chemistry (170), Garbenstrasse 28, DE-70599 Stuttgart, Germany.

Toxaphene, also known as camphechlor, is a persistent organochlorine pesticide of complex composition. It is technically produced by photochlorination of camphene with elemental chlorine gas under ultraviolet irradiation. In the present work, a novel, laboratory-scale synthesis using sulfuryl chloride as a chlorinating reagent is described. Read More

Arch Environ Contam Toxicol 2006 Nov 23;51(4):661-72. Epub 2006 Sep 23.

US Geological Survey (USGS), Columbia Environmental Research Center (CERC), 4200 New Haven Rd., Columbia, MO 65201, USA.

Organochlorine chemical residues and elemental contaminants were measured in northern pike (Esox lucius), longnose sucker (Catostomus catostomus), and burbot (Lota lota) from 10 sites in the Yukon River Basin (YRB) during 2002. Contaminant concentrations were compared to historical YRB data and to toxicity thresholds for fish and piscivorous wildlife from the scientific literature. A risk analysis was conducted to screen for potential hazards to piscivorous wildlife for contaminants that exceeded literature-based toxicity thresholds. Read More

J Toxicol Environ Health A 2006 Jun;69(12):1133-43

Department of Natural Resource Sciences and Center for Indigenous Peoples' Nutrition and Environment (CINE), McGill University, Ste. Anne de Bellevue, Quebec.

Elevated concentrations of organochlorines and mercury (Hg) have been reported in marine mammals on a global scale. While risk assessments are generally based on quantifying body burdens of toxicants, much less is known about associated adverse health effects and their underlying mechanisms. The purpose of this study was to characterize the inhibitory effects of methylmercury (MeHg+), mercuric chloride (Hg2+), p,p'-DDT, Arochlor 1254, chlordane,dieldrin, lindane, and toxaphene on [3H]quinuclidinyl benzilate ([3H]-QNB) binding to the muscarinic cholinergic (mACh) receptor in cellular membranes isolated from the cerebrum of ringed seals (Phoca hispida). Read More

Aquat Toxicol 2006 Jun 18;78(3):272-83. Epub 2006 Apr 18.

Department of Zoology, University of Florida, P.O. Box 118525, Gainesville, FL 32611-8525, United States.

In this study we describe an alligator hepatic CYP3A gene, CYP3A77, which is inducible by dexamethasone and toxaphene. CYP3A plays a broad role in biotransforming both exogenous compounds and endogenous hormones such as testosterone and estradiol. Alligators collected from sites in Florida that are contaminated with organochlorine compounds exhibit differences in sex steroid concentrations. Read More

Toxicol Sci 2006 Jun 24;91(2):501-9. Epub 2006 Mar 24.

INSERM, U540, F-34090 Montpellier, France.

Pregnane X receptor (PXR, NR1I2) is activated by various chemically unrelated compounds, including environmental pollutants and drugs. We proceeded here to in vitro screening of 28 pesticides with a new reporter system that detects human pregnane X receptor (hPXR) activators. The cell line was obtained by a two-step stable transfection of cervical cancer HeLa cells. Read More

Environ Monit Assess 2006 Feb;113(1-3):143-65

National Water Research Institute, Environment Canada, Burlington, ON.

In response to a number of recommendations following the Northern Rivers Basin Studies (NRBS) contaminant program, the Northern Rivers Ecosystem Initiative (NREI) focused considerable attention on assessing contaminants from specific sources including pulp mill effluents, atmospheric transport of mercury and the Alberta oil sands operations. NRBS identified a number of major contaminants of concern including polychlorinated biphenyls, dioxins and furans, mercury and various hydrocarbons. Together, the NRBS and the NREI studies have demonstrated major declines in the levels of dioxins and furans over the last decade as pulp and paper mills have changed their process and treatment strategies in response to new Federal regulations. Read More

Regul Toxicol Pharmacol 2006 Apr 10;44(3):268-81. Epub 2006 Feb 10.

US EPA Region 4, 61 Forsyth St. SW, Atlanta, GA 30303, USA.

Toxaphene is a mixture of chlorinated camphenes and bornanes that was produced and used in the United States until 1982. 1.3 million tons of toxaphene have been released worldwide. Read More

Arch Environ Contam Toxicol 2006 Nov 7;51(4):720-9. Epub 2006 Feb 7.

Research- and Technology Centre Westcoast, Christian-Albrechts-University Kiel, Büsum, Germany.

Previous studies have described high levels of polychlorobiphenyls (PCB), polybrominated diphenylether (PBDE), toxaphene, p,p'-dichlorodiphenyltrichloroethane (DDT), and p,p'-dichlorodiphenyldichloroethylene (DDE) in the blubber of the harbour porpoise from the North Sea raising the question of a potential endocrine disruption in this species. In the present study, the thyroids of 57 harbour porpoises from the German and Danish (North and Baltic Seas), Norwegian, and Icelandic coasts have been collected for histological and immunohistological investigations. The number of follicles and the relative distribution of follicles, connective, and solid tissues (%) were quantified in the thyroid of each individual. Read More