Exposure to organochlorine pesticides and polychlorinated biphenyls, adherence to an ideal cardiovascular health, and arterial stiffness among Chinese adults.

This study aimed to assess the relationships between exposure to individual organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and their mixture and arterial stiffness and explore whether adherence to an ideal cardiovascular health (CVH) could mitigate these associations. The cross-sectional study enrolled 1437 Chinese adults between March and May 2019 in Wuhan, China. OCPs and PCBs concentrations were measured using solid phase extraction coupled with gas chromatography-tandem mass spectrometry. Arterial stiffness was evaluated by brachial-ankle pulse wave velocity (baPWV). CVH was determined by three behavioral and four biological metrics and categorized as ideal, intermediate, and poor CVH. We applied generalized linear model and weighted quantile sum (WQS) regression to evaluate the associations of exposure to individual OCPs or PCBs and their mixture with baPWV, respectively. We found that participants with detectable levels of heptachlor epoxide, PCB-153, and PCB-180 had higher baPWV (ß: 34.25, 95% CI 14.28-54.22; ß: 27.64, 95% CI 7.90-47.38; and ß: 30.51, 95% CI 10.68-50.35) than those with undetectable levels. In WQS regression, the mixture of OCPs and PCBs was related to a higher baPWV (ß: 24.93, 95% CI 2.70-47.15). Compared with participants with ideal CVH and undetectable OCPs or PCBs levels, those with poor CVH and detectable OCPs or PCBs levels had the highest increase in baPWV (heptachlor epoxide: ß: 147.94, 95% CI 112.52-183.55; PCB-153: ß: 150.22, 95% CI 115.40-185.04; PCB-180: ß: 147.02, 95% CI 111.66-182.38). Our findings suggested that individual OCPs, PCBs, and their mixture exposure were positively associated with arterial stiffness, and adherence to an ideal CVH may mitigate the adverse effect.

Environmental and biological monitoring of organochlorine pesticides in the city of Salamanca, Mexico.

The former Tekchem Industrial Unit located in the city of Salamanca, Mexico, constitutes an environmental liability in which the presence of high levels of organochlorine pesticides (OCPs) has been reported. In the present study, levels of OCPs were quantified using gas chromatography-mass spectrometry in 52 soil samples and in 88 blood samples from school-age children in the city of Salamanca. A median concentration of 70.6 ng/g (6.93-3299) was obtained for total OCPs in soil, while for the total sum of dichlorodiphenyltrichloroethane (DDT) the value was 49.6 ng/g (6.93-3276). In children, the median level of the total sum of OCPs was 390 ng/g lipid (7.34-14,895), and for the total sum of DDT was 175 ng/g lipid (< LOD-14,802). The OCPs that resulted in highest concentrations in soil were DDT and its metabolites, as well as aldrin and heptachlor epoxide, while in blood the highest levels corresponded to 4,4'-dichlorodiphenyltrichloroethane (4,4'-DDT) and its metabolites, followed by heptachlor and heptachlor epoxide. The spatial distribution of the concentrations of OCPs in soil shows that the facilities of Tekchem may be a significant potential source for the dispersion of these compounds toward the metropolitan area of Salamanca. The results obtained in the present study demonstrate the presence of OCPs in soil and in child population, providing important bases to study the problem from a broader perspective, while reiterating the importance of continuing efforts to generate resolute and precautionary measures with respect to the environmental liability of Tekchem.

Human health risk assessment of pesticide residues in snappers (Lutjanus) fish from the Navachiste Lagoon complex, Mexico.

Organochlorine pesticides (OCPs) residues were determined in fillets of Lutjanus colorado, L. argentiventris, and L. novemfasciatus. Fillet samples were collected bimonthly from February 2012 to February 2013. OCPs average concentrations do not differ significantly according to size, weight, or season, nor do they relate with the physico-chemical parameters of the sea water. The highest concentration and most frequently encountered OCPs were endosulfan sulfate, δ-HCH, and heptachlor epoxide, which indicates their use in the recent past and confirms their persistence. Average concentrations of ∑HCHs, ∑chlordane, and ∑heptachlor in samples were above cancer MRLs according to data from monthly consumed portions. HCHs and heptachlor are listed in Appendix III of the Rotterdam Convention of chemicals placed on a prior informed consent procedure for import and export purposes; they are considered illegal in Mexico. The OCPs concentrations above cancer MRLs in Lutjanus spp. turn its frequent consumption into a human health risk.

Analysis of pesticide residues using the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) pesticide multiresidue method in traditional Chinese medicine by gas chromatography with electron capture detection.

The Quick Easy Cheap Effective Rugged and Safe multiresidue method (QuEChERS) has been validated for the extraction of 15 organochlorine pesticides (OCPs) in completely different matrices of traditional Chinese medicine (TCM). The method employed a rapid, simple and cost-effective procedure. The spiking levels for the recovery experiments were 0.1, 0.5 and 2.0 mg kg(-1). Mean recoveries mostly ranged between 76.0% and 114.0% (96.0% on average), and relative standard deviations (RSD) were generally below 10% (4.72% on average). Based on these results, the methodology has been proven to be highly efficient and robust and thus suitable for monitoring the MRL compliance of a wide range of commodity. The contamination status of 15 OCPs on 80 different TCMs marketed in China, and a total of 400 samples were also performed using a previously validated method. 15 OCPs were benzene hexachloride (BHC, including α-BHC, ß-BHC, γ-BHC, δ-BHC), hexachlorobenzene, heptachlor, heptachlor epoxide, aldrin, p, p'-DDE, p, p'-DDD, o, p'-DDT, p, p'-DDT, mirex, endrin, dieldrin. This study indicates that the proposed method is useful for analyzing OCPs in TCM.

Temporal trends of legacy POPs in Arctic biota, an update.

A statistically robust method was applied to 316 time-series of 'legacy' persistent organic pollutants (POPs) in Arctic biota from marine, freshwater and terrestrial ecosystems with the purpose of generating a 'meta-analysis' of temporal trend data collected over the past two to three decades for locations from Alaska in the west to northern Scandinavian in the east. Information from recently published temporal trend studies was tabulated and comparisons were also drawn with trends in arctic air. Most of the analysed time-series of legacy POP compounds showed decreasing trends, with only a few time-series showing significantly increasing trends. Compounds such as alpha-HCH, gamma-HCH and SigmaDDT had a relatively high proportion of time-series showing significantly decreasing trends; SigmaCHL had the lowest proportion. beta-HCH was an exception, where long-range transport through the ocean, and not the atmosphere, may explain several increasing trends that were detected in the Canadian Arctic. Moving east from the Canadian Arctic there was a trend towards a greater proportion of significantly decreasing trends. Several time-series for DDE and SigmaDDT showed significantly non-exponential trends, most often with a period of relative stability followed by a decrease. The median 'minimum detectable annual change within a 10-year period' for all of the time-series considered was 12% which did not meet the desirable level of statistical power capable of detecting a 5% annual change with a significance level of 5% within a 10-year period. The trends observed in the biota were consistent with decreasing trends of legacy POPs reported for Arctic air which appear to follow historic decreases in emissions. However, recent decreases in air are also starting to show signs of levelling off which may be an indication that atmospheric concentrations and, consequently those in the biota, are being less driven by primary sources and more by environmental processes and degradation.

Assessment of organochlorine pesticide levels in Manadas Creek, an urban tributary of the Rio Grande in Laredo, Texas.

The Rio Grande is the natural boundary between the United States and Mexico from El Paso, Texas, to Brownsville, Texas. It supports about 12 million people on both sides of the border for municipal, agricultural, industrial, and recreational uses. The rapid population and economic growth along the border region has led to increased pollution in the Rio Grande, which has been linked to several border health issues associated with pesticide contamination. This project was initiated to assess the organochlorine pesticide levels in the water and sediments in Manadas Creek, an urban tributary of the Rio Grande located in north Laredo, Texas. Water and sediment samples were collected monthly during a 6-month period from July to December of 2006 and analyzed using gas chromatography with an electron capture detector after extraction via a solid-phase microextraction technique. Among the water and sediment samples collected, several organochlorine pesticides including alpha-, beta-, and gamma-hexachlorocyclohexane (HCH), heptachlor epoxide, endrin, and 4,4'-DDT were found in either the creek water or sediments. Analysis of variance results indicated that only gamma-HCH had significant variation in the creek water among the sampling periods. Comparison of results with previous findings showed the presence of higher levels of HCH isomers and much lower DDT concentrations in the present study.

Occurrence and distribution of organochlorine pesticides - lindane, p,p'-DDT, and heptachlor epoxide - in surface water of China.

Persistent organochlorine pesticides pollutants (OCPs) have been reported to occur at relatively high concentrations in some Chinese waters. In order to map the distribution of organochlorine pesticides in the surface water throughout China, samples were collected from over 600 sites in seven major river basins and three main internal rivers drainage areas during 2003 and 2004. The surface water samples were analyzed for the representative organochlorine pesticides contaminants including lindane (gamma-HCH), p,p'-DDT and heptachlor epoxide. In general, the most frequently detected compound was lindane, being detected in 83.9% of samples (mean=31.3 ng/l; range <0.17-860 ng/l), and the highest concentration was present in the Yellow River basin. p,p'-DDT was detected in 63.1% of the samples collected (mean=14.6 ng/l; range <0.14-368 ng/l) with the highest concentration present in the Huaihe River basin. Heptachlor epoxide was detected in only 9.3% of water samples (range <0.11-10 ng/l). Measured concentrations for the three compounds were low and rarely exceed the environment quality standard for surface water of China. Lindane was more frequently detected at much higher concentrations in the rivers of northern China compared with those of southern China. The sites with higher concentration of lindane and p,p'-DDT mainly occurred in the Yellow River and Huaihe River basins, so the results of this investigation indicate that the organochlorine pesticide contamination of Yellow River and Huaihe River basins should be of particular concern relative to the other basins. When compared with other regions of the world, it appears that the Chinese surface water is moderately polluted by lindane and p,p'-DDT.

Residues of 18 organochlorine pesticides in 30 traditional Chinese medicines.

We analyzed 30 different traditional Chinese medicines (TCMs) to determine levels of contamination with organochlorine pesticides (OCPs). We tested for 18 pesticides: benzene hexachloride (BHC, including alpha-BHC, beta-BHC, gamma-BHC, delta-BHC), heptachlor, heptachlor epoxide, tecnazene, pentachloronitrobenzene (PCNB), hexachlorobenzene, aldrin, methyl pentachlorophenyl sulphide (MPCPS), alpha-endosulfan, trans-chlorodane, cis-chlorodane, p,p'-DDE, o,p'-DDT, p,p'-DDD, and p,p'-DDT. The sample extracts were analyzed by GC-ECD. A total of 280 samples of 30 different TCMs were analyzed. Our results showed that 75.8% of samples contained at least one of the above pesticides. The pesticides detected were tecnazene, hexachlorobenzene, PCNB, heptachlor, aldrin, alpha-BHC, beta-BHC, gamma-BHC, delta-BHC, p,p'-DDE, o,p'-DDT, p,p'-DDD p,p'-DDT. More than 50% of samples contained alpha-BHC (55.8%) and PCNB (55.8%); hexachlorobenzene was detected in 40.9% of samples, tecnazene in 19.5%, gamma-BHC in 16.7% and p,p'-DDE in 16.0%. Less than 10% of samples contained beta-BHC, delta-BHC, heptachlor, aldrin, o,p'-DDT, p,p'-DDT and p,p'-DDD. None of the 280 samples contained heptachlor epoxide, MPCPS, alpha-endosulfan, trans-chlorodane, or cis-chlorodane. Concentrations of OCPs in four samples exceeded the maximum allowable residue limits (MRLs) specified in the PRC Pharmacopoeia 2005. The results indicate that the most common contaminants among the 280 samples were alpha-BHC, PCNB, hexachlorobenzene, and tecnazene. Our results suggest that contamination of TCMs with OCPs is widespread. The MRLs for other OCPs commonly found in TCMs (e.g. hexachlorobenzene and tecnazene) should be set as quickly as possible, and the MRLs of OCPs in other TCMs should be established.

Removal of aldrin, dieldrin, heptachlor, and heptachlor epoxide using activated carbon and/or Pseudomonas fluorescens free cell cultures.

Degradation of aldrin (1,2,3,4,10,10-Hexachloro-1,4,4a,5,8,8a-hexahydro-1,4:5-8-dimethanonaphthalene), heptachlor (1H-1,4,5,6,7,8,8-heptachloro-3a,4,7,7a-tetrahydro-4,7-methano indene), dieldrin (1aalpha,2beta,2aalpha,3beta,6beta,6aalpha,7beta,7aalpha)-3,4,5,6,9,9-Hexachloro-1a,2,2a,3,6,6a,7,7a-octahydro-2,7:3,6-d-methanonaphtha[2,3-b]oxirene, and heptachlor epoxide (1aalpha, 1bbeta,2alpha,5alpha,5alphabeta,6beta,6aalpha-2,3,4,5,6,7,7-Heptachloro-1a,1b,5,5a,6,6a-hexahydro-2,5-methano-2H-inden[1,2-b]-oxirene) was tested using free cultures of Pseudomonas fluorescens under controlled conditions. Pesticide concentrations were monitored by gas chromatography during 120 h. Percentages of degradation and biodegradation rates (BDR) were calculated. Data showed a trend suggesting a relation between chemical structure and degradability. Degradation kinetics for each pesticide tested showed that the highest degradation rates were found in the first 24 h. Kinetics data were adjusted to an empirical equation in order to predict their behavior, and the correlation coefficients obtained were satisfactory. Gas chromatography/mass spectrometry (GC/MS) analysis of the final extracts allowed the identification of chlordene and monodechlorodieldrin, which have been reported as final metabolite produced in the biodegradation of this kind of compounds. Regarding adsorption of pesticides on activated vegetal carbon, we concluded that removal efficiencies between 95.45 and 97.18% can be reached, depending on the pesticide and the carbon dose applied. The values for K from the Freundlich equation were quite similar for the four pesticides (between 1.0001 and 1.04), whereas the n values were quite different for each pesticide in the following order of affinity: dieldrin > aldrin > heptachlor epoxide > heptachlor. Equilibrium times, very important for scaling up the process, were between 43 min and 1 h, for the heptachlor epoxide and the heptachlor, respectively.

Trends of chlorinated organic contaminants in great lakes trout and walleye from 1970 to 1998.

Levels of chlorinated organic contaminants in predator fish have been monitored annually in each of the Great Lakes since the 1970s. This article updates earlier reports with data from 1991 to 1998 for lake trout (Salvelinus namaycush) and (Lake Erie only) walleye (Sander vitreus) to provide a record that now extends nearly 30 years. Whole fish were analyzed for a number of industrial contaminants and pesticides, including polychlorinated biphenyls (PCBs), dichloro-diphenyl-trichloroethane (DDT), dieldrin, toxaphene, and mirex, and contaminant trends were quantified using multicompartment models. As in the past, fish from Lakes Michigan, Ontario, and Huron have the highest levels of PCBs, DDT, and dieldrin; Superior has the highest levels of toxaphene; and Ontario has the highest levels of mirex. In the period after curtailment of chemical use, concentrations rapidly decreased, represented by relatively short half-lives from approximately 1 to 9 years. Although trends depend on both the contaminant and the lake, in many cases the rate of decline has been decreasing, and concentrations are gradually approaching an irreducible concentration. For dioxin-like PCBs, levels have not been decreasing during the most recent 5-year period (1994 to 1998). In some cases, the year-to-year variation in contaminant levels is large, mainly because of food-web dynamics. Although this variation sometimes obscures long-term trends, the general pattern of a rapid decrease followed by slowing or leveling-off of the downward trend seems consistent across the Great Lakes, and future improvements of the magnitude seen in the 1970s and early 1980s likely will take much longer.

The link between the insecticide heptachlor epoxide, estradiol, and breast cancer.

Given the suspected effects of estrogens on breast cancer, xenoestrogenic insecticides may be a risk factor. Studies of the weak xenoestrogen, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), have failed to demonstrate a causal relationship, though another estrogenic organochlorine insecticide, dieldrin, belonging to the cyclodiene family, has recently been linked to breast cancer. Other cyclodienes such as heptachlor epoxide (HE) and oxychlordane (OC) present in breast tissue have not been evaluated as rigorously, presumably due to their lower concentration and lower recovery using solvent extraction procedures. We used sparging extraction coupled with gas chromatography to determine the levels of HE, OC, and DDE in adipose tissue within breast biopsies in a series of 34 women evaluated for breast abnormality. Of the three insecticides tested, only HE (p=0.007) was positively associated with prevalence of breast cancer in the biopsies. In rapid, non-genomic studies using isolated human leukocytes, flow cytometric methods were used to measure HE-induced oxidants and DNA damage. These studies indicated that HE, at concentrations similar to those in breast biopsies, induced an inverted-U increase in intracellular oxidants and DNA strand breaks [both blocked by specific nitric oxide- (NO-) synthesis blockade withL: -NMMA] in human polymorphonuclear leukocytes (PMNs). HE-treated PMNs also induced damage to surrounding lymphocytes in mixed-leukocyte incubations (also inhibited by NO blockade). The HE-induced changes in NO were inhibited by 17beta-estradiol-(17beta-E2) receptor antagonists and were mimicked by similar concentrations of 17beta-E2. The addition of tumor necrosis factor-alpha (TNF-alpha) increased intracellular oxidants and DNA damage and shifted the responses to lower HE concentrations. This study, along with others, suggests that HE-induced NO production may contribute to initiation, promotion, and progression of cancer.

Persistent organochlorine pesticides detected in blood and tissue samples of vultures from different localities in South Africa.

Gas chromatography was used to establish the presence of quantifiable residues of 14 persistent chlorinated hydrocarbon pollutants in whole blood, clotted blood, heart, kidney, liver and muscle samples obtained from individual African whitebacked (Pseudogyps africanus), Cape griffon (Gyps coprotheres) and Lappetfaced (Torgos tracheliotos) vultures from different localities in South Africa. The levels of pesticides measured in whole blood samples of live specimens were compared between nestlings from two natural breeding colonies, adults from a wildlife area and birds held in captivity. Statistically significant (P<0.05) differences between populations were detected in geometric means calculated for gamma-BHC (lindane), alpha(cis)-chlordane and alpha-endosulfan. Five of the organochlorine contaminants displayed significant variations between concentrations detected in the clotted blood, organs and muscles excised from vulture carcasses. This includes residues of gamma-BHC, alpha-chlordane, dieldrin, beta-endosulfan and heptachlor epoxide. Values of the respective biocides measured in vulture samples were generally low in comparison to results documented for a number of avian species. Although no threat is posed by any of the organochloride pesticides, continual monitoring of especially breeding colonies is recommended. Furthermore, the suitability of African whitebacked vulture nestlings as basic bioindicators is highly advocated.

Pesticides in precipitation in the Gdansk region (Poland).

Selected organonitrogen, organophosphorus and organochlorine pesticides have been determined in precipitation samples collected at 10 sites in the Gdansk region (northern Poland) over a period of one year (1998). Compounds which were detected most often included simazine (0.11-5.80 ng/l), fenitrothion (0.1-2.10 ng/l), chlorfenvinfos (0.1-1.30 ng/l), gamma-HCH (0.012-5.06 ng/l), heptachlor epoxide (0.05-3.28 ng/l) and aldrin (0.02-3.28 ng/l). The pesticide concentrations in precipitation samples revealed seasonal fluctuations, with higher concentrations observed during the application periods (June and July). The concentrations observed were also affected by the inflow of polluted air masses from the southwest. The total pesticide concentration in the precipitation samples was strongly related to the abundance of green areas in the vicinity of the sampling sites. A weak correlation was also found between the total concentration of organonitrogen and organophosphorus pesticides, and the total concentration of organochlorine pesticides in the samples collected.

The effects of perinatal/juvenile heptachlor exposure on adult immune and reproductive system function in rats.

This study was performed to determine if developmental exposure of rats to heptachlor (H) during the last half of gestation through puberty adversely affects adult functioning of the immune and reproductive systems. Time-bred pregnant female Sprague-Dawley rats were dosed by gavage with H (0, 30, 300, or 3000 microg/kg/day) from gestation day (GD) 12 to postnatal day (PND) 7, followed by direct dosing of the pups with H through PND 42. Separate groups of rats were evaluated with a battery of immune function tests, while other groups of rats were evaluated for reproductive development and function. Additional groups of rats were euthanized at the end of the dosing period for histological analyses of major organ systems. Some dams and PND 7 pups were euthanized; milk, plasma, fat and/or tissues were assayed for H and heptachlor epoxide B (HEB), a major metabolite of H. The amount of H and HEB found in milk, blood, fat, and tissues was proportional to the dose of H administered. There were no effects on the number or survival of pups born to H-exposed dams nor to pups exposed postnatally. There were no effects on the number of treated dams delivering litters or on litter size, nor were there any effects on any of the reproductive end points examined in the F(0) or F(1) rats. There were no effects of H exposure on lymphoid organ weights, splenic natural killer (NK) cell activity, and splenic lymphoproliferative (LP) responses to mitogens and allogeneic cells in a mixed lymphocyte response (MLR) assay at 8 weeks of age. H exposure did not alter delayed or contact hypersensitivity at 10 or 17 weeks of age, respectively. However, the primary IgM antibody response to sheep red blood cells (SRBCs) was suppressed in a dose-dependent manner in males, but not females, at 8 weeks of age. The percentage of B lymphocytes (OX12(+)OX19(-)) in spleen was also reduced in the high-dose males. The anti-SRBC IgM response was reduced only in males exposed to 30 microg H/kg/day in a separate group of rats 21 weeks of age. In these same rats, at 26 weeks of age, the secondary IgG antibody response to SRBCs was suppressed in all of the H-exposed males, but not females. These data indicate that perinatal exposure of male rats to H results in suppression of the primary IgM and secondary IgG anti-SRBC responses. Suppression of these antibody responses persisted for up to 20 weeks after the last exposure to H, at a total exposure of approximately 1500 microg H/kg/rat.

Organochlorine contaminant levels in Eskimo harvested bowhead whales of arctic Alaska.

Organochlorine (OC) levels in liver and blubber of 20 bowhead whales (Balaena mysticetus) collected during the Eskimo subsistence harvest at Barrow (Alaska, USA) in 1992 and 1993 are presented. Liver sum DDT (lipid weight) was significantly greater in male whales than in females. Most of the organochlorines measured were at higher levels in longer (older) than in shorter (younger) males. For female bowhead whales, hexachlorobenzene and lipid levels decreased and other OC levels did not change significantly with increasing length. Most organochlorine contaminants have low concentrations in tissues of the bowhead whale compared to concentrations in tissues of other cetaceans, especially Odontocetes. Based on allowable daily intakes (ADI) levels established by the Canadian Northern Contaminants Program (Ottawa, Ontario, Canada) "safe" levels of blubber to consume were calculated. Chlordane levels in bowhead whale blubber results in the most restrictive consumption amount (50 g blubber/day). We expect no adverse effects related to these organochlorine contaminants to occur in bowhead whales or in consumers of their tissues. However, investigation of low level chronic exposure effects and a more rigorous assessment of histopathology, biomarkers, and immune status in the bowhead whale would be required to conclude "no effect" with more certainty.

Organochlorine pesticide residues in muscle tissue of rainbow trout, Oncorhynchus mykiss, taken from four fish farms in León, Spain.

Levels of nine organochlorine pesticides (lindane, heptachlor epoxide, aldrin, dieldrin, endrin, o,p'-TDE, p,p'-TDE, p,p'-DDE and p,p'-DDT) were determined in muscle samples of rainbow trout, Onchorhynchus mykiss, collected from four fish farms in the province of León, in the north-west of Spain (Europe). The highest incidence percentage was for lindane (67.5%) and heptachlor epoxide (55.0%). Organochlorine residue levels detected contributed slightly to acceptable daily intakes (ADIs) established by the Food and Agriculture Organization of the United Nations and the World Health Organization (lindane 0.22-2.3%; sigma DDT 0.05-0.46%; heptachlor epoxide 10.0-71.4% and sigma dieldrin 16.7-33.3% assuming 300 g of trout muscle as a mean daily intake). The highest concentration found was for heptachlor epoxide (0.043 microgram/g).

Contamination of human breast milk with organochlorine residues: a comparison between East and West Germany through sentinel practice networks.

STUDY OBJECTIVE: The aim of the study was to assess and compare the contamination of human breast milk with organochlorine residues through two sentinel practice networks in Lower Saxony, a state of former West Germany, and Saxony-Anhalt, a state of former East Germany. DESIGN: Eligible women were enrolled in this cross sectional study by a network of 51 paediatric practices in Lower Saxony and 44 in Saxony-Anhalt when bringing their babies for a regular screening examination four to six weeks after delivery. Sociodemographic, lifestyle, and exposure factors were determined by questionnaire. Milk samples were analysed for hexachlorocyclohexane (HCH), hexachlorbenzole (HCB), DDT, dieldrin, polychlorinated biphenyls (PCB), and heptachlorepoxid (HCE); half the samples were also analysed for dioxin. Analytic statistics were computed using multiple logistic regression. SETTING: The study was conducted in Lower Saxony, Germany, from July 1992 to June 1993, and in Saxony-Anhalt, Germany, from January to June 1995. PARTICIPANTS: 156 primiparous, breast-feeding women from Lower Saxony and 113 from Saxony-Anhalt were studied, who either were born and raised in former West or East Germany, respectively. MAIN RESULT: Mean age of mothers and children differed significantly between the two study groups. In Lower Saxony all but two milk samples were well below the tolerable concentrations established by the German Research Council (Deutsche Forschungsgemeinschaft (DFG)). In Saxony-Anhalt no participant had concentrations above those recommended by the DFG. After adjustment for age of mother and child, occupational and non-occupational pesticide contact, DDT and beta-HCH concentrations were significantly lower in Lower Saxony; HCE and dieldrin concentrations were lower in Saxony-Anhalt. No differences between the two states were found for PCB, HCB, gamma-HCH, and dioxin. CONCLUSIONS: Breast milk contamination levels in former East German Saxony-Anhalt exceeded the contamination in Lower Saxony only for DDT and beta-HCH.

Termite control and other determinants of high body burdens of cyclodiene insecticides.

Breast milk fat concentrations of three cyclodiene insecticides--dieldrin, heptachlor epoxide, and oxychlordane--were measured in 797 primiparous women, and sources of exposure that contributed significantly to high body burdens were investigated. All three distributions were highly skewed to the right, with median concentrations falling between 0.007 and 0.039 mg/kg. Termite control of residence was associated consistently with being in the high-body-burden group for all three compounds, but the association was greatest for heptachlor. Age, socioeconomic status, residential area, smoking, and home use of insecticides were also associated with high body burden of one or more of the compounds, but the odds ratios were lower than those for termite control; the findings were inconsistent for the three compounds. The results for termite control remained statistically significant when we adjusted for the other factors; therefore, termite control of residence is an important risk factor for cyclodiene insecticide absorption.

Screening of nonfatty fish for organochlorine pesticide residues by solid-phase extraction cleanup: interlaboratory study.

Six U.S. Food and Drug Administration laboratories participated in an Interlaboratory trial of a solid-phase extraction cleanup method for determination of pesticides in nonfatty seafood products. The participants analyzed control and fortified (about 0.050 ppm lindane, heptachlor epoxide, p,p'-DDE, and endrin) croaker and flounder samples and a sea trout sample containing incurred p,p'-DDE residues. Mean recoveries of the fortified residues from the fish ranged from 89.1 to 107.8%. The within-laboratory coefficients of variation (CVs) ranged from 4.2 to 8.5%, and the among-laboratory CVs ranged from 10.9 to 26.5%. The 6 laboratories reported a mean value of 0.040 ppm p,p'-DDE in a fish sample which contained incurred residues. The same value (0.040 ppm) was obtained by using official methodology. The within-laboratory CVs ranged from 3.5 to 18.3%, and the among-laboratory CV was 17.3%.

Detection of some organochlorine pesticides in cow's milk.

This monitoring study of 192 samples of cow's milk collected from the central region of Veracruz state was conducted to determine the contamination levels of organochlorine pesticides. The results obtained for mean DDT and HCH levels were 0.057 and 0.098 mg/kg respectively expressed on fat basis and are within FAO tolerances and similar to those found in other tropical countries.