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No abstract available. [ABSTRACT FROM AUTHOR]

Isomers and metabolites of the organochlorine pesticide chlordane persist in the environment and bioaccumulate in Arctic marine food webs. Rodent studies indicate that there are gender-related differences in trans-nonachlor and oxychlordane metabolism. Thus, comparative tissue depletion studies were undertaken in male and female rats exposed to trans-nonachlor, oxychlordane, or trans-chlordane at 2.5 mg/kg body weight/d by gavage for 28 d followed by two consecutive 28-d depletion periods. None of the test chemicals were overtly toxic at this dose, although increased liver weights in some groups were consistent with microsomal enzyme induction. The metabolite oxychlordane accumulated in tissues from rats exposed to trans-nonachlor and trans-chlordane. trans-Nonachlor and oxychlordane residue levels were highest in tissues from female rats at each time point; however, trans-chlordane was completely eliminated from males and females by the end of the study. Body burden calculations showed no significant clearance of oxychlordane in females over 56 d postdosing, whereas males lost approximately half their oxychlordane body burden in the same period. For the chiral contaminants oxychlordane and trans-chlordane, tissues from male and female rats were selectively depleted of the (+)-enantiomer; however, there were gender-related differences in enantiomer depletion patterns over time. In general, residue analyses confirmed that gender-related metabolic differences and contaminant structural properties, including chirality, influenced chlordane contaminant elimination from rat tissues. The study points to a need for similar knowledge of gender-related responses in humans in order to provide relevant dietary recommendations for populations exposed to chlordane-related contaminants in foods. [ABSTRACT FROM AUTHOR]

Chiral pesticides frequently undergo enantioselective degradation in soils. Prior studies to characterize chiral signatures have focused on treated agricultural soils, rather than background (untreated) soils, and tracking signatures in the atmosphere for source apportionment purposes. In this study, we investigated the chiral signatures in 65 background soils collected from different locations across the world. The soils were taken from different ecosystems (e.g., grasslands,forests), and the enantiomeric fractions(EFs) of chiral chlordanes, α-hexachlorocyclohexane (α-HCH), and o,p'-DDT were determined. Chlordanes in most of the soils showed the usual pattern of enantioselective degradation seen in agricultural soils, depletion of (+)-trans- chlordane (TC) and (-)-cis-chlordane (CC). However, some samples showed opposite enantiomer degradation patterns for TC, CC, and chlordane compound MC5. Correlations were tested between the deviation of EFs from racemic (DEVrac = absolute value of 0.500 - EF), the percent soil organic matter (% SOM), annual mean temperature, and the ratio of TC to the more stable compound trans-nonachlor (TN). Significant positive correlations were found between DEVrac and % SUM for TC and CC (p = 0.0022 and 0,0031), but not for the other OCPs. No significant correlations were found between OEVrac and annual mean temperature for any of the OCPs. DEVrac for TC was negatively correlated with the TC/TN ratio, but the regression was driven by two points with high ratios of TC/CC. Removing these two points resulted in a nonsignificant regression. The range of EFs for TC, CC, and α-HCH in soils was greater than in ambient air, providing evidence of in situ degradation after atmospheric deposition in some cases. Variable EFs in soil suggest that caution is needed when considering the enantiomer signatures in air as a marker of volatilization of weathered soil-derived organochlorines. [ABSTRACT FROM AUTHOR]

Abstract: Chlordane comes under the group of persistent organic pollutants, which, according to the Stockholm Convention, should be completely prohibited or widely limited. Within the Environmental and Health Monitoring Programme the National Institute of Public Health in Prague, Centre for the Hygiene of Food Chains in Brno, is involved in a project, which explores the dietary exposure of the population of the Czech Republic to chemical substances. In order to meet the demands it is necessary to obtain data which would contribute to a comprehensive description of exposure doses of the priority persistent organic pollutants based on the Stockholm Convention. Hence alpha- and gamma-chlordane and oxychlordane were incorporated into the project in 2002. Chlordane was monitored in food samples of the so-called food basket of the Czech population. After culinary treatment the food samples underwent extraction, were purified (GPC, Florisil) and analysed (GC-ECD). The method for determination of chlordanes in food was developed in our laboratory and was validated. Internal standards were used to determine the recovery of the analytical procedure. The limits of quantification depended on the type of the matrix and ranged between 0.002 and 0.05 μgkg−1. CRM 598 BCR and proficiency testing (FAPAS) are used to assure that the method provides data of required precision and accuracy. The method is accredited by the Czech Accreditation Institute. In the majority of analysed samples the content of chlordane was below the limit of quantification. The highest amount of chlordanes was found in freshwater fish (2.78 μgkg−1), butter and vegetable fat. The results of monitoring are used for estimation of the dietary exposure of the population of the Czech Republic to these substances. [Copyright &y& Elsevier]

Abstract: The Dniester River is one of the largest rivers in Eastern Europe and receives input from numerous anthropogenic activities. In October 2001, fish samples (Abramis brama, Rutilus rutilus heckeli, Perca fluviatilis, Chondrostoma nasus, Carassius auratus gibelio, and Cyprinus carpio) were collected and analyzed for metals and various pesticides. Maximum total DDT pesticide concentrations were between 27.7 and 34.2ng/g wet weight in muscles and gonads, respectively. DDE isomers comprised up to 70% of total DDT measurement in fish tissues, indicating historical rather than recent DDT pollution. Chlordane and lindane were also detected in amounts up to 37 and 76ng/g wet weight in gonads, respectively. Among organophosphorous pesticides, malathion showed extremely high concentrations—3μg/g wet weight in muscles and 46μg/g wet weight in gonads, indicating recent exposure. Copper concentrations in muscles (1.8–7.2μg/g) exceeded Threshold Effect Concentrations for copper in fish. Detection of high concentrations of malathion and copper in fish tissues indicated potential anthropogenic stress for more sensitive aquatic biota, likely from agricultural sources in the Dniester River. [Copyright &y& Elsevier]

Abstract: Chlordane is a widely used organochlorine insecticide. In order to evaluate its perturbing effect upon the morphology of human erythrocytes it was caused to interact with human red cells and molecular models of cell membranes. These consisted in bilayers of dimyristoylphosphatidylethanolamine (DMPE) and of dimyristoylphosphatidylcholine (DMPC), representative of phospholipid classes located in the inner and outer monolayers of the erythrocyte membrane, respectively. Scanning electron microscopy (SEM) observations indicated that this pesticide induced a significant alteration in the shape of the erythrocytes as they changed their discoid shape to spherocytes. According to the bilayer couple hypothesis, the shape changes induced in erythrocytes by foreign molecules are due to differential expansion of their two monolayers. The fact that chlordane produced spherocytes would indicate that the pesticide was equally located in the outer and the inner moieties of the red cell membrane. This conclusion was supported by the results obtained from X-ray diffraction studies. These showed that the hydrophobic and polar head regions of DMPC bilayers were perturbed when the insecticide was in a 1:10 molar ratio with respect to the lipid. These results were confirmed by the fluorescence experiments performed in DMPC large unilamellar vesicles (LUV). Chlordane produced a sharp decrease in the anisotropy and general polarization parameters in the 0–0.1mM range, implying an increase in the fluidity at the acyl chain and polar region of DMPC. On the other hand, the bilayer structure of DMPE was perturbed in a fashion similar to that observed by X-ray diffraction in DMPC, a fact that explains the morphological change induced by chlordane to the human erythrocytes. [Copyright &y& Elsevier]

Until recently, analytical results were normally stated as declared values, sporadically associated with strict uncertainty evaluation. Current trends in analytical chemistry require traceable data together with fully evaluated uncertainty. Polychlorinated biphenyls (PCBs) and chlordanes are considered in this paper from the standpoint of the uncertainty of their determination in drinking water. Using headspace solid-phase microextraction (HS-SPME) and GC-MS/MS, it was possible to reach low ng/L levels of quantification in drinking water for seven marker PCBs and two chlordane isomers, with a relative global uncertainty associated with the results of all contaminants ranging from 11 to 38%. Although the assessed relative uncertainties of the results can be considered acceptable and may even be further improved at higher concentration ranges, they may have considerable importance for levels close to the detection limits of the method, where they may represent more than 100% of variation for the stated result. [ABSTRACT FROM AUTHOR]

Abstract: This study examined the effects of the organochlorine (OC) insecticides chlordane, o,p′-DDT, dieldrin, endosulfan, kepone, methoxychlor, and toxaphene on human HepG2 cytochrome P450 (1A-EROD and 2B-PROD) activities and glutathione (GSH) levels. Cells were exposed for 24h at high concentrations (1, 5 or 10mM) and for 48h at lower concentrations ranging from 0.01 to 1mM to evaluate dose responses. Our results show that after 48h all but dieldrin significantly induced both P4501A and 2B. P4502B responses were greater at all exposure concentrations and times. Mixed responses in GSH levels were observed. All OCs except dieldrin and MXC significantly depleted GSH after 24h. At 48h, chlordane, endosulfan and toxaphene significantly increased GSH at low levels and decreased GSH at high levels, while kepone and methoxychlor produced significant declines in GSH at all concentrations. These results support findings of OC insecticides inducing CYP1A, 2B in rats, with CYP2B responses more important. GSH levels declined when P4502B activity was significantly elevated and were significantly increased in the absence of significant P450 activity, suggesting that GSH levels influence the catalytic activity of the cytochrome P450s and the cytochrome P450s influence the cell’s ability to regulate GSH. [Copyright &y& Elsevier]

Three types of tissue samples—umbilical cord (UC), umbilical cord serum (CS), and maternal serum (MS)—have often been used to assess fetal exposure to chemicals. In order to know the relationship of contamination between mothers and fetuses, we measured persistent chemicals in comparable sets of the three tissue samples. Also, we analyzed the association between the chemicals in maternal and fetal tissues to know which tissue is the best sample for fetal exposure assessment. On a wet basis, the chemical concentrations were of the order MS > CS > UC, except for some chemicals such as cis-chlordane and endosulfan. On a lipid basis, the concentrations in UC were nearly equal or often higher than in MS, but the concentrations in CS were usually lower than in others. Hexachlorocyclohexanes and penta-, hexa-, and heptachlorinated biphenyls showed an association between the concentrations in UC versus MS, and UC versus CS. These chemicals also showed high correlation coefficients between the chemical concentrations in UC of first babies and maternal age. These chemicals were closely related to each other when grouped on the basis of their concentrations using cluster analysis. In conclusion, we insist that UC is the best sample to assess fetal contamination status of persistent chemicals. There is a possibility that the assessment based on the contamination levels in CS result in an underestimation. [ABSTRACT FROM AUTHOR]

Investigates the characteristics and spatial distribution of total chlordane from rivers in the United States. Result of Kriging analysis in two areas; Concentration of total chlordane; Effects of grain size on sediment chlordane contamination.

Fourier transform infrared spectral measurement and complete normal mode calculations have been carried out for heptachlor and wedge modes have been identi?ed. In addition, valence charge distributions have been obtained for aldrin, endrin, heptachlor, beta-endosulfan, cis-chlordane, trans-chlordane, photo-cis-chlordane and photo-trans-chlordane using CNDO/2 (complete neglect of differential overlap) molecular orbital calculations. A toxicity parameter has been de?ned as the product of the charge distribution and surface area of the corresponding active wedges, depending on the interacting structural features. The variation of this toxicity parameter is generally in order and in agreement with the reported measurements based on the corresponding order of observed ld50 values. Because of the structural features, the toxicity in these cases is a surface phenomenon rather than a volume effect as in the case of Gammexane, wherein the insecticide binds itself to membrane channels. Because the biological activity is a dynamic rather than a static phenomenon, it is expected that the normal modes involving the wedge atoms play an important role. Copyright 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of chlordane and lindane on morphological changes and endocrine disruption in male Green neon shrimp (Neocaridina denticulata). In this experiment, individuals of N. denticulata, a common inhabitant of freshwater systems in Taiwan, were exposed to chlordane (1 and 10ng/l) and lindane (0.1 and 1μg/l). Morphological changes and reproductive hormone levels were observed following four weeks exposure. According to our findings, an increase in estrogen, a reduction in testosterone, and morphological alternations of the masculine appendage were observed in both chlordane- and lindane-treated shrimp, while induction of a vitellogenin-like protein appeared only in shrimp treated with 10ng/l chlordane. An endocrine disruption effect on N. denticulata was demonstrated, and may apply to other organochlorine pesticides or endocrine disruption chemicals. [Copyright &y& Elsevier]

Abstract: Chlordane was used as an insecticide for half a century until its withdrawal from the world market in 1997. Trans- and cis-chlordane (TC, CC) are racemic in the technical product, but undergo enantioselective degradation in soil to leave nonracemic residues. In most cases, the (+) enantiomer of TC and the (-) enantiomer of CC are depleted, leading to enantiomer fractions, ], that are for TC and for CC. Nonracemic EFs of TC and CC, showing the same degradation preference as soils, were found in 1998–2001 air samples from stations in Arctic Canada and Finland, and on the west coast of Sweden. Environmental samples representing different time periods of chlordane history were also examined in: (a) archived atmospheric deposition samples collected in Sweden, Slovakia and Iceland in 1971–1973, (b) soils from southern Sweden sampled in 2001 and (c) a laminated lake sediment core from the Canadian Arctic representing ∼50 years of accumulation. TC and CC were racemic or nearly so in the historical atmospheric deposition samples and nonracemic in the Swedish soils. The EF of TC in the dated lake sediment core decreased from nearly racemic in the past to nonracemic in recent times. These observations suggest that sources of chlordane to the atmosphere have changed over time and are now influenced to a greater extent by emission from soils. [Copyright &y& Elsevier]

It has been observed that plants are susceptible to uptake from soil and in planta transport of technical chlordane, in spite of its hydrophobicity and sequestration within the soil matrix due to weathering. Field and rhizotron studies were conducted with Cucurbitaceae planted in highly weathered, chlordane-contaminated soil to investigate details of soil-to-plant contaminant uptake. In the field-work, Cucurbita pepo L. (zucchini) was grown in soil at four levels of chlordane contamination: Clean (

Organochlorine pesticides are used worldwide. To our knowledge there have been no studies dealing with the effects of these agents under in vitro conditions on human natural killer (NK) cell cytotoxic function. NK cells play a central role in immune defense against tumor development and viral infections. Thus, any agent that interferes with the ability of NK cells to lyse their targets could increase the risk of tumor incidence and/or viral infections. In this study, we examined the effects of organochlorine pesticides and some of their breakdown products on the ability of human NK cells to lyse tumor cells. A total of 11 compounds were tested. The compounds were tested in both purified NK cells as well as a cell preparation that contained other mononuclear cells (predominantly T cells) and NK lymphocytes (referred to as T/NK cells). Lymphocytes were exposed to the compounds for periods of time ranging from 1 hour to 6 days. Exposure of highly purified NK cells to μM α-chlordane, γ-chlordane, 4,4'-DDT, heptachlor, oxychlordane, or pen- tachlorophenol (PCP) inhibited their ability to destroy K562 tumor-cells by 88±5, 9±8, 61±13%, 64±10%, 69±11%, 76±12%, respectively, after a 24 h exposure. The loss of cytotoxic function seen with α-andγ -chlordane remained essentially constant out to 6 days, while that seen with 4,4'-DDT, oxychordane and PCP increased with longer exposures (6 d). PCP was the most effective of the compounds tested at decreasing NK function. Of the compounds that caused decreased lytic function when tested in purified NK cells, only PCP and oxychordane decreased the lytic function of the T/NK cell preparation after any exposure. The results provide evidence of relative toxic potential for the 11 compounds and their immunomodulatory effects on other mononuclear cells (such as T-cells, B-cells, and monocytes) as well as NK lymphocyte function. [ABSTRACT FROM AUTHOR]

The present study determined the concentrations of organochlorines (OCs) such as polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), hexachlorobenzene (HCB) and tris(4-chlorophenyl)methane (TCPMe) in human breast milk collected from primiparae in Dalian and Shenyang, northeastern China during 2002. In addition, dioxins and related compounds in pooled samples of human breast milk from Dalian and Shenyang were also analyzed. OCs were detected in all the human breast milk samples analyzed in this study. The predominant contaminants in human breast milk were HCHs, DDTs and HCB, and the levels were relatively higher than those in other countries. On the other hand, concentrations of dioxins and related compounds, PCBs, and CHLs were relatively low. Concentrations of OCs in human breast milk from Dalian, which is located along the coast of Bo Hai Strait, were significantly higher than those from Shenyang, implying that the residents in Dalian might be mainly exposed to these contaminants from seafood. When the relationship between concentrations of OCs in human breast milk and age of primiparae was examined, no significant correlation was observed. This might be caused by the limited sample numbers and narrow range of mother''s age and/or recent ban of DDT and HCH production and use. Significant correlation between concentrations of TCPMe and DDTs in human breast milk suggested that technical DDT might be a source of TCPMe in the Chinese population. When daily intakes of DDTs and HCHs to infants through human breast milk were estimated, human breast milk from Dalian showed significantly higher contribution than Shenyang, implying that infants in Dalian might be at higher risk by these contaminants. [Copyright &y& Elsevier]

The present study was under taken to demonstrate the effect of some commonly used insecticides on the activity of cytochrome P450 system including cytochrome b5, aryl hydrocarbon [benzo(a)pyrene] hydroxylase (AHH), N-nirosodimethylamine N-demethylase I [NDMA-dI] and NADPH-cytochrome c reductase as phase I of drug oxidation. In addition, the activity of glutathione S-transferase (GST), glutathione reductase (GR), and the level of glutathione (GSH) were determined in the liver of male mice after oral administration of sumithion, dursban, chlordane, methoxychlor, heptachlor epoxide, and lindane as single (24 h) or as repeated doses for six consecutive days. Oral administration of sumithion, dursban, chlordane, methoxychlore, and heptachlor epoxide as repeated doses decreased: (i) the hepatic content of cytochrome P450 by 36, 37, 47, 37, and 67%, respectively, (ii) AHH activity by 28, 29, 70, 31, and 79%, respectively, (iii) NDMA-dI activity by 43, 44, 32, 27, and 31, respectively. On the other hand, sumithion, chlordane, and methoxychlore induced the activity of NADPH-cytochrome c reductase by 45, 62, and 43 respectively after repeated dose treatments. In addition, single and repeated-dose treatments of mice with lindane induced; (i) cytochrome P450 by 23 and 65%, respectively, (ii) cytochrome b5 by 49 and 131%, respectively, (iii) AHH activity by 64 and 50%, respectively. Repeated-dose treatments of mice with chlordane, methoxychlore, and heptachlor epoxide decreased the GSH level by 42, 38, and 68%, respectively and GST activity by 44, 44, and 55% respectively. Moreover, single- and repeated-dose treatments of mice with lindane decreased the GSH levels by 40 and 54%, respectively, and induced GST activity by 25 and 41%, respectively. Interestingly, single-dose treatments with chlordane, methoxychlore, and heptachlor epoxide decreased the activity of GR by 32, 38, and 31, respectively whereas repeated doses of these compounds induced such activity by 83, 50, and 64%, respectively. It is concluded that modifications in cytochrome P450 system by pesticides could potentiate the toxicity and carcinogenicity of environmental carcinogens such as polycyclic aromatic hydrocarbon and N-nirosodimethylamine (NDMA). [ABSTRACT FROM AUTHOR]

To characterize the atmospheric dynamics and behavior of chlordane compounds in the mid-Atlantic region of the United States, atmospheric concentrations were measured in 1997-1999 at three New Jersey locations as part of the New Jersey Atmospheric Deposition Network (NJADN) project. Observed concentrations of Σ-chIordanes (cischlordane + trans-chlordane + cis-nonachlor + trans- nonachlor) are log-normally distributed, with a geometric mean concentration of 77.1 pg m-3 and range from 6.1 to 481 pg m-3. Gas-phase species comprised 83% (±23%) of the Σ-chlordanes species across all samples at all location. Gas-phase Σ-chlordane concentrations are inversely proportional to temperature, with higher concentrations during periods of warmer air temperatures. Observed concentrations do not correlate with wind direction or air mass history, which suggests that observed concentrations in the New Jersey atmosphere are due to volatilization from soils and surfaces on the regional scale. [ABSTRACT FROM AUTHOR]

The chlordane constituent trans-nonachlor and its metabolite oxychlordane are among the most persistent chlordane-related contaminants and are found in tissues and milk from humans ingesting diets high in Arctic marine mammal fat. Although chlordane is no longer registered in North America, there is a need for toxicological data on chlordane-related contaminants found in food and the environment which are either structurally different or relatively more abundant than the constituents of the original chlordane mixture. Thus, a feeding study was undertaken to provide toxicological data on trans-nonachlor. Male and female Sprague-Dawley rats were exposed to 0, 5, 13 or 50 ppm trans-nonachlor in feed for 90 days and clinical, hematological and histopathological changes were assessed in each rat. Female rats were less able than males to metabolize and eliminate trans-nonachlor and, as a result, accumulated more trans-nonachlor in their adipose tissues. trans-Nonachlor, like technical chlordane and other organochlorines, induced liver microsomal enzymes in a pattern similar to phenobarbital. Endocrine effects included functional and morphological changes in the thyroid and adrenals. In male rats exposure to trans-nonachlor was associated with changes in endpoints indicative of increased oxidative stress, which may be related to both direct action on cellular targets or to secondary effects resulting from cytochrome P450 induction. The results indicate that subchronic trans-nonachlor exposure in rats induced hepatic changes with far-reaching metabolic and endocrine effects. Differences in target organ responses in male and female rats indicate that the sex-related metabolic differences affecting trans-nonachlor bioaccumulation and elimination merit further study. [Copyright &y& Elsevier]

Indoor and outdoor concentrations of six chlordane components (trans-chlordane, cis-chlordane, trans-nonachlor, cisnonachlor, oxychlordane, and MC5) were measured at 157 residences, all of which were inhabited by nonsmoking individuals, in three urban areas during June 1999-May 2000. The analyses were conducted on a subset of 48 h integrated samples collected in Los Angeles County, CA, Houston, TX, and Elizabeth, NJ within the Relationship of Indoor, Outdoor, and Personal Air (RIOPA) study. Both particle-bound (PM2.5; quartz fiber filter) and vapor-phase (PUF sorbant) chlordane concentrations were separately measured by GC/El MS after solvent extraction. The outdoor (gas + particle) total chlordane (trans-chlordane + cis-chlordane + trans-nonachlor + cis-nonachlor) concentrations ranged from 0.036 to 4.27 ng m-3 in Los Angeles County, from 0.008 to 11.00 ng m-3 in Elizabeth, and from 0.062 to 1.77 ng m-3 in Houston. The corresponding indoor total chlordane concentrations ranged from 0.037 to 112.0 ng m-3 in Los Angeles County, from 0.260 to 31.80 ng m-3 in Elizabeth, and from 0.410 to 38.90 ng m-3 in Houston study homes. Geometric mean concentrations were higher in indoor air than outdoor air (1.98 vs 0.58 ng m-3 in CA; 1.30 vs 0.17 ng m-3 in NJ; 4.18 vs 0.28 ng m-3 in TX), which suggests there are significant indoor sources of chlordane species in a subset of homes in each of the three cities. Calculated source strengths relate to home age, with the highest apparent indoor source strengths occurring in unattached single-family homes built during the period from 1945 to 1959. Principle indoor sources of chlordanes likely include volatilization from residues of indoor application of chlordanes and infiltration from subsurface and foundation application of chlordane-containing termiticides during home construction. [ABSTRACT FROM AUTHOR]

Mono- through octachlorinated naphthalenes (PCNs) were measured in start-up, steady operation, and shutdown of machinery operation flue gas and fly ash generated during different stages of MSWI and other incineration thermal processes. Besides, electroprecipitator fly ash (EP-ash) was dechlorinated using the Hagenmeier process and analyzed for congener profiles. In addition to PCNs, polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and major organochlorine pesticides were determined in ambient air samples from three different sites of western Japan in the summer and winter of 1992. The PCNs from flue gas contained 15,000, 4300, and 13,000 ng/m³ during start-up, steady operation, and shutdown conditions, respectively. Whereas fly ash contained 470, 370, and 1400 ng/g PCNs under start-up, steady operation, and shutdown condition, respectively. The dechlorination process reduced PCN concentrations considerably. Concentrations of PCNs and PCDD/PCDFs in air samples, collected in winter were slightly higher than in summer. PCBs, organochlorine pesticides such as chlordanes, DDTs, and HCHs were higher in summer air samples. WHO toxic equivalency (WHO-TEQ) concentrations in air samples were 0.3–0.9 pg/m³ for PCDD/DFs and 0.029–0.31 pg/m³ for dioxin-like PCBs. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the acute toxicity of chlordane and lindane as well as their endocrine disruption effect on green neon shrimp (Neocaridina denticulata), a common habitant in freshwater system of eastern Asia and Hawaii. First, the organisms were exposed to chlordane and lindane to estimate the 96-h LC50(96-h median lethal concentration). Then, levels of testosterone and vitellogenin in hemolymph of N. denticulata after exposure to sublethal concentrations of chlordane (1 ng/L and 10 ng/L) and lindane (0.1 μg/L and 1 μg/L) were also examined. The 96-h LC50 values obtained from the results of acute exposure were 127.03 (130.11–122.35) ng/L and 9.36 (8.00–10.96) μg/L for chlordane and lindane, respectively. Furthermore, reductions of testosterone concentration were observed in both chlordane- and lindane-treated shrimps, whereas induction of vitellogenin-like protein was only apparent in chlordane-treated shrimps. Thus, it is concluded that chlordane and lindane may probably show some disruption endocrine functions on N. denticulata. [ABSTRACT FROM AUTHOR]

The current study examined the effects on the redeared slider turtle of extremely low doses of three endocrinedisrupting compounds (EDCs)—trans-Nonachlor, chlordane, and p,p'-DDE—singly and in mixtures. Previous studies using the red-eared slider turtle have proven its value as an organism for obtaining information about the effects of endocrine-disrupting compounds. The sex of the turtle, easily manipulated by exposure during embryogenesis, continues to be a marker of effects. When red-eared slider turtle embryos incubating at a temperature that normally produces a male-biased sex ratio are exposed to these compounds singly, the sex ratio of the resulting hatchlings shifts significantly to a female bias. The current work offers further evidence that the red-eared slider turtle provides a way to quantify the effects of mixtures and has the potential as a model for evaluating additivity and synergy. The results provide information about how very low doses (parts per billion) of these compounds behave in mixtures. The dose ranges were 0.125-0.5 ng/egg for trans-Nonachlor and chlordane and 7-28 ng/egg for p,p'-DDE. Results suggest the possibility that two of the compounds may exert effects in mixtures via complementary pathways; when applied singly, the effects of chlordane and p,p'-DDE were inversely related to dose, but in mixtures, which were essentially a greater dose of EDC, the compounds had an increased effect. In all cases, mixtures resulted in 100% females. [ABSTRACT FROM AUTHOR]

Analytical high-performance liquid chromatographic separations of the individual enantiomers of five polychlorinated compounds were obtained on polysaccharide stereoselective HPLC columns. The enantiomers of the pesticides trans-chlordane, cis-chlordane and heptachlor were separated on CHIRALCEL®OD using a hexane mobile phase. The enantiomers of the heptachlor metabolite, heptachlor epoxide, were separated on CHIRALPAK®AD using a methanol mobile phase. The enantiomers of α-hexachlorocyclohexane (α-HCH), were separated on CHIRALCEL®OJ using a hexane/2-propanol mobile phase. Similar chromatographic conditions using preparative columns were used to isolate approximately 250 mg of each of the individual enantiomers. The purified individual enantiomers have been submitted for testing of their endocrine disruptor (ED) activity. [Copyright &y& Elsevier]

Epidemiologic studies have used both questionnaires and carpet dust sampling to assess residential exposure to pesticides. The consistency of the information provided by these two approaches has not been explored. In a population-based case-control study of non-Hodgkin's lymphoma, carpet dust samples were collected from the homes of 513 control subjects in Detroit, Iowa, Los Angeles, and Seattle. The samples were taken from used vacuum cleaner bags and analyzed for 30 pesticides. Interviewers queried subjects about the types of pests treated in their home using a detailed questionnaire accompanied by visual aids. Geographic variations in pesticide levels were generally consistent with geographic differences in pest treatment practices. Los Angeles residents reported the most treatment for crawling insects, fleas/ticks, and termites, and Los Angeles dust samples had the highest levels of propoxur, chlorpyrifos, diazinon, permethrin, and chlordane. Iowa had the most treatment for lawn/garden weeds, and also the highest levels of 2,4-dichlorophenoxyacetic acid and dicamba. Although Seattle had the highest proportion of subjects treating for lawn/garden insects, the lawn/garden insecticides were higher in other sites. Multivariate linear regression revealed several significant associations between the type of pest treated and dust levels of specific pesticides. The strongest associations were between termite treatment and chlordane, and flea/tick treatment and permethrin. Most of the significant associations were consistent with known uses of the pesticides; few expected associations were absent. The consistency between the questionnaire data and pesticide residues measured in dust lends credibility to both methods for assessing residential exposure to pesticides. The combined techniques appear promising for epidemiologic studies. Interviewing is the only way to assess pesticide exposures before current carpets were in place. Dust sampling provides an objective measure of specific compounds to which a person may have been exposed through personal use of a pesticide or by drift-in or track-in from outside, and avoids recall bias.Journal of Exposure Analysis and Environmental Epidemiology (2004) 14, 74-83. doi:10.1038/sj.jea.7500307 [ABSTRACT FROM AUTHOR]

Twenty-seven black guillemot eggs and 39 livers were analysed for polychlorinated biphenyls (PCBs), chlorinated pesticides including chlordane-related compounds and toxaphene, and polybrominated diphenylethers (PBDEs). The samples were collected at Qeqertarsuaq (Godhavn, West Greenland) and Ittoqqortoormiit (Scoresbysund, East Greenland). The concentrations of halogenated organic compounds in samples from East Greenland were somewhat higher than the corresponding concentrations from West Greenland. Differences in compound patterns were found between West and East Greenland, with higher percentages of the heavier PCB molecules, p,p′-DDE and α-HCH in the samples from Ittoqqortoormiit. Similarly, different levels and different compositions were observed for eggs and livers. The eggs had generally higher concentrations of all compounds as well as higher percentages of CHB-50, CHB-62 and α-HCH than liver samples from the same area. Dividing the liver samples into age groups revealed increasing concentrations with age. [Copyright &y& Elsevier]

To mitigate the impact on the environment of persistent organic pollutants (POPs), we must understand thoroughly their environmental fate. Residues of many of these pollutants are still present in soil years after their legitimate uses were banned. In this report, the volatilization of one such persistent pollutant, chlordane, from a field where it was applied approximately 40 years ago, is examined in detail over the course of several years. Ambient air samples were collected at three heights above the treated soil throughout the investigation. Air samples were also collected at several background sites in Connecticut for comparison. Analysis of these samples shows that chlordane volatilization from soil continues to occur long after initial application, at rates dependent on both temperature and cultivation of the soil. Comparison of relative concentrations and enantiomeric profiles for components of technical chlordane in atmospheric samples from a variety of sources suggests a regional, urban input of chlordane to the ambient air over Connecticut, possibly related to the widespread termiticidal use of chlordane in home foundation soils. [ABSTRACT FROM AUTHOR]

In order to assess fully the impact of persistent organic pollutants (POPs) on human health, pollutant exchange at the interface between terrestrial plants, in particular food crops, and other environmental compartments must be thoroughly understood. In this regard, transfers of multicomponent and chiral pollutants are particularly informative. In the present study, zucchini (Cucurbita pepo L.) was planted in containerized, uncontaminated soil under both greenhouse and field conditions and exposed to air-borne chlordane contamination at 14.0 and 0.20 ng/m3 (average, greenhouses), and 2.2 ng/m3 (average, field). Chiral gas chromatography interfaced to an ion trap mass spectrometer was used to determine the chiral (trans-chlordane, TC, and cis-chlordane, CC) and achiral (trans-nonachlor, TN) chlordane components in vegetation, air, and soil compartments. The chlordane components of interest were detected in all vegetation tissues examined––root, stem, leaves, and fruits. When compared with the data from a soil-to-plant uptake study, the compositional profile of the chlordane components, i.e. the component fractions of TC, CC, and TN, in plant tissues, showed significantly different patterns between the air-to-plant and soil-to-plant pathways. Changes in the enantiomer fractions of TC and CC in plant tissues relative to the source, i.e. air or soil, although observed, were not markedly different between the two routes. This report provides the first comprehensive comparison between two distinct plant uptake routes for POPs and their subsequent translocation within plant tissues. [Copyright &y& Elsevier]

Examines the effect of xenoestrogens from fat depots on the survival of patients after thermal injury. Level of heptachlor epoxide and oxychlordane in nonsurvivors; Factor causing the difficulty in accounting the postburn alterations in heptachlor epoxide and oxychlordane concentrations;Contribution of xenostrogens to the mortality of older patients;

Due to widespread usage of the pesticide chlordane until the 1980′s, this toxic and persistent mixture has accumulated in the food chain. The Arctic acts as a global sink for these and other persistent organic pollutants, which bioaccumulate in the marine and freshwater food chains. As a result, humans consuming diets high in Arctic fish and marine mammal fat can ingest higher levels of chlordane contaminants than humans consuming “southern” diets. The most abundant constituents of the chlordane mixture are trans-chlordane, cis-chlordane, trans-nonachlor, cis-nonachlor and heptachlor; oxychlordane is the major metabolite of the chlordanes and nonachlors. In humans the predominant chlordane-related contaminants detected in breast milk and adipose tissues are trans-nonachlor and oxychlordane. The present studies were undertaken to provide toxicological data on oxychlordane for the purpose of clarifying target organ toxicity and risks to human health associated with ingesting contaminated foods. Female rats were gavaged with oxychlordane at doses ranging from 0.01 to 10 mg/kg body weight/day for up to 28 days. In terms of general toxicity oxychlordane had a steep dose-response curve: 10 mg/kg oxychlordane was acutely toxic and 1 mg/kg oxychlordane caused no measurable effects. Weight loss, reduced feed consumption and thymic atrophy were the hallmarks of acute oxychlordane toxicity. At lower doses rats showed signs of hepatic changes indicative of microsomal enzyme induction. Oxychlordane was more bioaccumulative and was toxic at levels approximately 8 times lower than trans-nonachlor and cis-nonachlor. Thus, ingestion of trans-nonachlor and related chlordane contaminants in foods results in the formation of a metabolite that is more toxic and bioaccumulative than the parent contaminants. [Copyright &y& Elsevier]

Increases in non-Hodgkin's lymphoma (NHL) incidence and mortality rates during the past few decades remain largely unexplained. Studies suggest that organochlorine pesticides may contribute to an increased risk of NHL. In 1974, serum samples were obtained from 25,802 participants in the Campaign Against Cancer and Stroke in Washington County, Maryland (USA), and cryopreserved for future study. We measured prediagnostic levels of chlordane, lindane (γ-hexachlorocyclohexane), β-hexachlorocyclohexane, transnonachlor, heptachlor, heptachlor epoxide, oxychlordane, dieldrin, and hexachlorobenzene in serum samples of 74 cases of NHL and 147 matched controls. Previously, we found an association between NHL and serum levels of total PCBs (polychlorinated biphenyls), but not DDT (dichlorodiphenyltrichloroethane) and related compounds. In this instance, there was no evidence of an association between NHL risk and serum levels of any of the individual lipid- and recovery-corrected organochlorines that we evaluated, nor of the summed chlordane-related compounds (transnonachlor, heptachlor, heptachlor epoxide, oxychlordane). These findings do not support the hypothesis that the organochlorine compounds included in this study are strongly linked to the development of NHL. The possibility of a weak association cannot be excluded by these data. [ABSTRACT FROM AUTHOR]

fostering autonomyIn this paper we develop an ethical perspective for public and environmental health practice in consideration of the "right to know" by contrasting consequential and deontological perspectives with relational ethics grounded in the concept of fostering autonomy. From the consequential perspective, disclosure of public and environmental health risks to the public depends on the expected or possible consequences. We discuss three major concerns with this perspective: respect for persons, justice, and ignorance. From a deontological perspective, the "right to know" means that there is a "duty" to communicate about all public health risks and consideration of the principles of prevention, precaution, and environmental justice. Relational ethics develops from consideration of a mutual limitation of the traditional perspectives. Relational ethics is grounded in the relationship between the public and public/environmental health providers. In this paper we develop a model for this relationship, which we call "fostering autonomy through mutually respectful relationships." Fostering autonomy is both an end in public health practice and a means to promote the principles of prevention, precaution, and environmental justice. We discuss these principles as they relate to practical issues of major disasters and contaminants in food, such as DDT, toxaphene, chlordane, and mercury. [ABSTRACT FROM AUTHOR]

The immunotoxicity of cis- and trans-nonachlor and chlordane were investigated in adult male and female Sprague–Dawley rats following a 28-day oral (gavage) treatment. Rats were randomly assigned to six experimental groups: cis-nonachlor, females; trans-nonachlor, females; technical chlordane females; cis-nonachlor, males; trans-nonachlor, males; technical chlordane, males. The immunologic endpoints included: quantification of the total serum immunoglobulin (Ig) levels and subclasses and flow cytometric analysis of peripheral blood leukocytes and T-lymphocyte subsets, evaluation of the lymphoproliferative activity of splenocytes in response to concanavalin A (Con A) and Salmonella typhimurium (STM) mitogens, and natural killer (NK) cell activity of splenocytes. Satellite experiments to examine the delayed-type hypersensitivity (DTH) response to oxazolone, and resistance to Listeria monocytogenes were set up for female rats treated with cis- or trans-nonachlor. Statistically significant (P<0.05) effects included: increased serum immunoglobulin M (IgM) levels in the chlordane-treated females at the 25 mg/kg dose (pairwise comparison); increased serum IgG1 and IgG2c in the cis-nonachlor-treated males at the 2.5 and 25 mg/kg doses and increased serum IgG2a levels at all doses; increased serum IgG2b at the 25 mg/kg dose and decreased (dose-related) serum IgM levels in the cis-nonachlor-treated male rats; increased (linear trend) IgG1 and IgG2a in the cis-nonachlor-treated females with effects on IgG2a significant at the 25 mg/kg dose compared with control; increased serum IgG2a in the trans-nonachlor-treated male and female rats at the 2.5 mg/kg dose; increased absolute numbers (linear trend) of peripheral white blood cells, B lymphocytes, natural killer (NK) cells, T-suppressor/cytotoxic lymphocytes, and the double positive (T-helper/inducer, T-suppressor/cytotoxic) cells in the trans-nonachlor-treated females; increased (non-linear trend) lymphoproliferative activity in the Con A-stimulated splenocytes and decreased (linear trend) activity in the S. typhimurium mitogen-stimulated splenocytes of the cis-nonachlor-treated females; reduced resistance to L. monocytogenes in the cis-nonachlor (day 3, P=0.034)- and trans-nonachlor (day 2, P=0.0001)-treated females, and reduced (linear trend) NK cell activity in the cis-nonachlor-treated males. The present data indicated that the chlordane compounds tested in this study had significant effects on a number of immunologic endpoints. In comparison to technical chlordane, cis- and trans-nonachlors were more immunotoxic. Therefore, an evaluation of the risk these chlorinated compounds may pose to human health should consider the potential effects different chlordane compounds may have on the immune system. [Copyright &y& Elsevier]

Investigates the presences of persistent organic pollutants in vegetation-based environmental compartments. Examination of the technical chlordane residues in a variety of compost; Quantification of the source of contamination; Application of chiral gas chromatography interfaced.

The study was carried out to quantitate the transfer of toxaphene and chlordane compounds from commercial fish feed into the edible part of rainbow trout, Oncorhynchus mykiss (Walbaum) under normal rearing conditions. Trout were fed with unspiked high energy feed for salmon (fat content 26-30%) over a period of 19 months. The average weight of trout increased from 10 g to more than 2092 g, reaching sizes of 51 cm length. Considerable amounts of toxaphene and chlordane residues were transferred from fish feed into trout muscle. Toxaphene concentrations increased up to 8.6 µg (Σ toxaphene indicator compounds 1-3)kg[sup -1] wet weight (w.w.) and chlordane reached 5.3 µg Σoxy-, trans-, cis-chlordane + t-nonachlor kg[sup -1] w.w. Results are also discussed on the contaminant levels based on the fat content and the effect of sexual maturation is considered in this study. The data allow the establishment of transfer rates for toxaphene and chlordane congeners from high energy diet into the edible part of farmed rainbow trout. [ABSTRACT FROM AUTHOR]

Examines the compositional and chiral profiles of weathered chlordane pesticide residues in the soil and vegetative compartments. Pesticide transport; Chlordane concentration in the rhizosphere; Persistent organic pollutants.

Examines the presence of chlordane compounds in arctic air in the U.S. Assessment on the changing source composition of chlordane; Identification of nonceramic heptachlor exo-epoxide; Influence of soil emissions in the long-range transport of chlordane compounds.

Technical chlordane, a synthetic organic pesticide composed of 147 separate components, some of which exhibit optical activity, was used as an insecticide, herbicide, and termiticide prior to all uses being banned in the United States in 1988. It has been shown that food crops grown in soil treated decades earlier with technical chlordane translocate the weathered chlordane residues from the soil into root and aerial plant tissues. A rigorous analytical method is presented for the simultaneous, quantitative determination of both achiral and chiral components of technical chlordane in soil, plant, and air compartments using chiral gas chromatography interfaced to ion trap mass spectrometry and internal standard calibration. Using this method, we have observed differences in both the absolute and the relative amounts of trans- and cis-chlordane enantiomers and achiral trans-nonachlor between the soil compartment and various plant tissue compartments for several field-grown food crops. Changes in the relative amounts of the (+) and (-) enantiomers of trans- and cis-hlordane indicate enantioselective processes are in effect in the contiguous compartments of soil, plant roots, and aerial plant tissues. The data for zucchini (Cucurbita pepo L.), in particular, show an approximate fivefold enhancement in absolute concentration for total trans-chlordane, an eightfold concentration enhancement for total cis-chlordane, and a 2.5-fold enhancement for trans-nonachlor in the root relative to the soil matrix, the largest enhancements of any crop studied. This is the first comprehensive report of enantioselective processes into and through plant tissues for a variety of field-grown food crops. The selectivity will be related to observed insect toxicities of the enantiomers [ABSTRACT FROM AUTHOR]

The fate of chlordane and other persistent organic pollutants in the environment is of international concern. The behavior of persistent organic pollutants under both abiotic and biotic conditions must be determined for the comprehensive elucidation of their cycling through the biosphere. Standard analytical methods such as gas chromatography with electron capture detection are adequate for studies of cycling under abiotic conditions. Since two of the main components of technical chlordane, cischlordane and transchlordane, are optically active, chiral gas chromatography can be used to study the impact of biotic influences on chlordane's fate. We report here the use of chiral gas chromatography interfaced with ion trap mass spectrometry as part of an analytically rigorous method for the simultaneous determination of the compositional and chiral profiles of weathered soil residues of technical chlordane. Using the method described, several patterns in the long-term weathering of technical chlordane in soil are observed. [ABSTRACT FROM AUTHOR]

We have recently reported that human neutrophils are important targets of different xenobiotics, including chemicals of environmental concern. In the present study, we found that chlordane was not toxic for human neutrophils incubated for up to 24 h with concentrations ranging from 0.1 to 50 g/ml. Chlordane was found to induce neutrophil superoxide production (O[sub 2][sup -]) in a concentration-dependent fashion and its potency to induce this response was found to be similar to phorbol 12–myristate 13–acetate (PMA), a classical neutrophil agonist. The use of different transduction signal inhibitors (genistein, pertussis toxin, staurosporine, and calphostin C) indicates that, as for PMA, chlordane induces O[sub 2][sup -] production via protein kinase C (PKC). In this respect, staurosporine and calphostin C were found to inhibit chlordane- and PMA-induced O[sub 2][sup -] production by 65% and 72%, and by 83% and 85%, respectively. Chlordane was also found to significantly enhance neutrophil phagocytosis of opsonized sheep red blood cells (SRBCs). Despite these effects, chlordane did not alter neutrophil apoptosis as assessed by cytology (Diff-Quick staining) and by flow cytometry (CD-16 expression). In addition, chlordane did not alter neutrophil chemotaxis (48-well Boyden chamber). Cells were, however, responsive as they were activated by the well-characterized interleukin (IL)-8 chemokine. We conclude that chlordane can activate O[sub 2][sup -] production by a PKC-dependent mechanism and induce phagocytosis without altering chemotaxis and apoptosis. Chlordane must be added to a growing list of environmental contaminants that share some pro-inflammatory properties. Human & Experimental Toxicology (2001) 20, 229–235. [ABSTRACT FROM AUTHOR]

We have observed recurring chlordane poisonings of large numbers of common grackles (Quiscalus quiscula), European starlings (Sturnus vulgaris), and American robins (Turdus migratorius) at suburban roosts in New Jersey during the month of July. This paper describes aspects of the food chain uptake of chlordane that account for the periodicity of these poisonings. Chlordane concentrations ranged from < 0.02 to 20.3 μg/g wet weight in 11 soil samples collected from residential lawns and a golf course near one roost. Of the 10 species of insects and soil invertebrates collected from the area, two scarab beetles, the oriental beetle (Anomala orientalis) and Japanese beetle (Popilla japonica), had the highest concentrations of chlordane-related compounds (15.1 and 5.9 μg/g wet weight, respectively). Concentrations in the other eight species ranged from < 0.04 to 1.3 μg/g. Oriental and Japanese beetles collected from a rural location had concentrations of 0.03 and < 0.02 μg/g, respectively. Emergence of adult beetles peaked in mid- to late July, when bird mortality also peaked. Fecal pellets collected near the roost (n = 24) contained the remains of 1–5 beetles each (mean = 2), and scarab beetles accounted for 40% of the total number of insect parts in the stomach contents of common grackles (n = 8). Unlike soil samples, in which cis- and trans-chlordane predominated, beetles contained large amounts of the more toxic metabolites heptachlor epoxide and oxychlordane. Total chlordane-related compounds ranged from < 0.05 to 18.4 μg/g in Japanese beetles collected from 16 sites in New Jersey and 2 sites in Ohio. The highest concentrations were found in beetles from suburban areas and golf courses. We also analyzed brain tissue from insectivorous bats (15 big brown bats, Eptesicus fuscus, and 5 little brown bats, Myotis lucifugus) that were submitted to the New Jersey Rabies Laboratory in late June/July 1998 and 1999 but found to be rabies-negative. We suggest that high concentrations in three of the bats caused debility or abnormal behavior that may have precipitated submission for rabies testing. [ABSTRACT FROM AUTHOR]

Examines the levels of air pollution caused by organochlorine pesticides in Alabama between October 1996 and May 1997. Determination of seasonal toxaphene and chlordan levels in the air; Concentration of contaminant levels compared with that of the Great Lakes region.

The article cites a study that compared the dose-responsive effects of toxaphene as well as the two cyclodiene insecticides chlordane and heptachior on glutathione content and interconversion in CHO-KI cells, to ascertain whether oxidative stress is involved in the toxicity of these pesticides in mammalian cells. Insecticide cytotoxicity was estimated in CHO-KI cells using the neutral red (NR) uptake assay. Researchers concluded that cyclodiene pesticides induced increases in total glutathione peroxidase activity in CHO-KI cultures after exposure for 24 hours. Whereas total glutahtione content remained unchanged after exposure to chlordane due to a significant increase in glutathione reductase levels, the tripeptide content was low after exposure to heptachlor.

Fifty paddlefish (Polyodon spathula) collected from two sites on the Ohio River and from one site on the Cumberland River, USA, were examined to determine gonad polychlorinated biphenyl (PCB) and chlordane concentrations, amounts of plasma sex steroids (testosterone and estradiol), hepatic microsomal ethoxyresorufin-O-deethylase (EROD) activity, and the presence of immunoreactive cytochrome P450 1A (CYP1A) protein. Percent hatch and liver, spleen, and kidney histology were also determined. Gonad PCB and chlordane concentrations were significantly higher in Ohio River paddlefish than in Cumberland River paddlefish. Gonad PCB and chlordane concentration and gonad percent lipid were correlated in Ohio River paddlefish. Five of 10 Ohio River egg samples exceeded the Food and Drug Administration's action limit for chlordane (0.30 mg/g). Polychlorinated biphenyl congenerspecific analysis detected predominantly the tetra-, penta-, and hexachlorobiphenyls in paddlefish testes. Plasma testosterone levels were significantly lower in males collected from the upper Ohio River site than those collected from the lower part of the river. There was no measurable hepatic microsomal EROD activity in any of the 50 paddlefish collected from the three sites. Western blotting analysis confirmed that a rabbit antitrout CYP1A1 IgG antibody did not recognize a CYP1A protein in paddlefish liver microsomes. Percent hatch was not significantly different in eggs collected from the Cumberland (88-96%) and Ohio Rivers (90- 95%). Histological analysis of liver, spleen, and kidney detected the presence of hepatic steatosis and hemosiderosis, splenic lymphoid cell depletion, and hyperplasia of interrenal and chromaffin tissues. Immunosuppression, hepatic metabolic disorders, and altered neuroendocrine function may be occurring in Ohio River paddlefish. Results presented here suggest that organochlorine exposure may be jeopardizing the long-term health of Ohio River paddlefish and that additiona... [ABSTRACT FROM AUTHOR]

Examines the enantiomer ratios (ER) of alpha-hexachlorocyclohexane and chlordane related compounds in the polar bear food chain. Near-racemic fixtures for the compounds in the cod; Calculation of apparent chiral biomagnification factors; Relationships between ER, chemical residue concentrations and biological data.

Indicates that the enantiomer ratios of some chlordane congeners were found to be gender-specific in cod from the Barents Sea. Presence of concentrations of U81, U82, transchlordane, MC5, cischlordane, MC7, trans-nonachlor as well as metabolites cis-heptachlorepoxide and oxychlordane; Differences caused by dissimilar feeding habits of male and female cods.

Examines the effects of the xenobiotics chlordan, trans-nonachlor and Aroclor 1242 on steroid hormone concentrations of red-eared slider turtles. Limited study on the effect of xenobiotics on physiology; Examination of steroid concentrations in treated turtles; Scope of effects of endocrine disruptors.