Explore the vast range of titles available.

Background Studies have shown associations of diabetes and endogenous hormones with exposure to a wide variety of organochlorines. We have previously reported positive associations of polychlorinated biphenyls (PCBs) and inverse associations of selected steroid hormones with diabetes in postmenopausal women previously employed in a capacitor manufacturing plant. Methods This paper examines associations of PCBs with diabetes and endogenous hormones in 63 men previously employed at the same plant who in 1996 underwent surveys of their exposure and medical history and collection of bloods and urine for measurements of PCBs, lipids, liver function, hematologic markers and endogenous hormones. Results PCB exposure was positively associated with diabetes and age and inversely associated with thyroid stimulating hormone and triiodothyronine-uptake. History of diabetes was significantly related to total PCBs and all PCB functional groupings, but not to quarters worked and job score, after control for potential confounders. None of the exposures were related to insulin resistance (HOMA-IR) in non-diabetic men. Conclusions Associations of PCBs with specific endogenous hormones differ in some respects from previous findings in postmenopausal women employed at the capacitor plant. Results from this study, however, do confirm previous reports relating PCB exposure to diabetes and suggest that these associations are not mediated by measured endogenous hormones.

There are limited data on the concentrations of common contaminants--polychlorinated biphenyls (PCBs), dichlorodiphenyl dichloroethene (pp'-DDE) and hexachlorobenzene (HCB)--in umbilical cord blood. Cord blood provides the primary direct measure of prenatal exposure to these contaminants, the key determinant of PCBs' neurodevelopmental toxicities. The objective of this study was to characterize cord blood levels of PCBs, pp'-DDE, and HCB among 751 infants who were born between 1993 and 1998 to mothers residing adjacent to a PCB-contaminated harbor in New Bedford, Massachusetts, and for whom the neurodevelopmental toxicities of these compounds are being studied. We refined standard analytic methods to optimize the sensitivity and precision of trace-level PCB, p,p'-DDE, and HCB measurements in blood. Using these methods, we measured the concentrations of 51 individual PCBs, their sum (sum(PCB)), p,p'-DDE, and HCB in cord serum. With correction for background contamination, the respective mean+/-SD cord serum concentrations of sum(PCB), p,p'-DDE, and HCB were 0.54+/-0.83, 0.48+/-0.94, and 0.03+/-0.04 ng/g serum. These concentrations were generally lower than those in most of the few published studies with congener-specific measures of PCBs in cord blood. However, for less-chlorinated PCB congeners (e.g., congeners 99 and 118), study samples had concentrations comparable to those in other populations, including groups at risk for high dietary PCB exposure. Of note, the contaminated harbor sediment has a relatively high proportion of less-chlorinated PCB congeners. Thus, although the sum(PCB) in study infants was not higher than concentrations in infants studied elsewhere, the relative predominance of less-chlorinated congeners was generally consistent with the characteristics of the contaminated site.

To determine the contaminants that should be studied further in the subsequent population-based study, a profile of Great Lakes (GL) sport fish contaminant residues were studied in human blood and urine specimens from 32 sport fish consumers from three Great Lakes: Lake Michigan (n = 10), Lake Huron (n = 11), and Lake Erie (n = 11). Serum was analyzed for 8 polychlorinated dioxin congeners, 10 polychlorinated furan congeners, 4 coplanar and 32 other polychlorinated biphenyl (PCB) congeners, and 11 persistent chlorinated pesticides. Whole blood was analyzed for mercury and lead. Urine samples were analyzed for 10 nonpersistent pesticides (or their metabolites) and 5 metals. One individual was excluded from statistical analysis because of an unusual exposure to selected analytes. Overall, the sample (n = 31) consumed, on average, 49 GL sport fish meals per year for a mean of 33 years. On average, the general population in the GL basin consume 6 meals of GL sport fish per year. The mean tissue levels of most persistent, bioaccumulative compounds also found in GL sport fish ranged from less than a twofold increase to that of PCB 126, which was eight times the selected background levels found in the general population. The overall mean total toxic equivalent for dioxins, furans, and coplanar PCBs were greater than selected background levels in the general population (dioxins, 1.8 times; furans, 2.4 times; and coplanar PCBs, 9.6 times). The nonpersistent pesticides and most metals were not identified in unusual concentrations. A contaminant pattern among lake subgroups was evident. Lake Erie sport fish consumers had consistently lower contaminant concentrations than consumers of sport fish from Lakes Michigan and Huron. These interlake differences are consistent with contaminant patterns seen in sport fish tissue from the respective lakes; GL sport fish consumption was the most likely explanation for observed contaminant levels among this sample. Frequent consumers of sport fish proved to be effective sentinels for identifying sport fish contaminants of concern. In the larger study to follow, serum samples will be tested for PCBs (congener specific and coplanar), DDE, dioxin, and furans.

In support of a study to relate developmental and cognitive effects with prenatal exposure to selected environmental toxicants, we developed and applied an analytical method to determine the concentration of two persistent pesticides, hexachlorobenzene (HCB) and p,p'-dichlorodiphenyldichloroethylene (DDE), and 32 specific polychlorinated biphenyl (PCB) congeners in 316 umbilical cords taken in 1986-1987 from women of the Faroe Islands. The analytical method consisted of homogenization of the cords, partitioning, microsilica gel column chromatography for clean-up, and dual-column capillary gas chromatography (DB-5 and DB-1701) with electron capture detection. Several quality control parameters were followed to monitor the performance of the method. Important criteria used before reporting unknown data were the recovery of in vitro-spiked analytes from a bovine umbilical cord (BUC) and the percentage lipid obtained for a Certified Reference Material (CRM)-350 of mackerel oil (MO). Recoveries of analytes that had been spiked at two concentration ranges (0.26-0.95 ng/g whole weight; 0.35-2.42 ng/g whole weight) into bovine cords ranged from 38.5% to 158% and from 50.4% to 145%, respectively, with a median recovery of 77.7%. Measurement of the percentage lipid for CRM-350 ranged from 73.8% to 107% with a median lipid value of 96.0%. The most prevalent analytes detected (%) in unknown umbilical cords were HCB (100), DDE (100), Ballschmiter/Zell PCBs 153 (100), 138 (98), 180 (98), 170 (93), 118 (88), 187 (86), and 146 (83), with corresponding median concentrations (ng/g whole weight) of 0.17, 1.19, 0.38, 0.30, 0.17, 0.11, 0.12, 0.09, and 0.07, respectively. Total PCB--sum of all measurable PCB congeners--had a median concentration of 1.37 ng/g whole weight. The analytes, which were very low in lipid content were also quantified on a lipid-adjusted basis, which provided an analytical challenge in these umbilical cord samples. The gravimetrically measured lipids in the human specimens ranged from 0.01% to 1.43% (median of 0.18%). In the pooled BUCs, our lipid measurements varied from 0.05% to 0.33% with a median value of 0.13%. The utility of using the umbilical cord as a matrix to assess in utero exposure to persistent environmental pollutants, compared with the use of umbilical cord blood or mother's blood, is worthy of debate.

In a preliminary study, 12 male and 12 female weanling Sherman strain rats were given a single dose of 1000 mg polybrominated biphenyls (PBBs) FireMaster FF1 Lot 7042 kg/body weight as a 5% solution in corn oil. Three male and three female weanling rats were given corn oil. One day after dosing PBB blood levels ranged from 78 to 162 ppm and 42 days later they ranged from 1.1 to 2.99 ppm. The liver was the only organ with pathological changes. In a long-term recovery study groups of 20 male and female rats, 2 months old, were given 0 or 1000 mg PBBs/kg body weight as a single dose in peanut oil. Five rats per group killed 2, 6, 10, and 14 months after dosing had pronounced liver pathology, including hepatic porphyria in the female rats and neoplastic nodules also mainly in female rats. Chemical analyses of blood, liver, and adipose tissue for PBBs 10 and 14 months after dosing gave the following mean results. Blood levels in females were 2.9 and 2.92 ppm, respectively, and males 0.94 and 1.34 ppm, respectively. Adipose tissue levels in females were 1202 and 783 ppm and in males 713 and 866 ppm, respectively. The liver levels in females were 37 and 22 ppm and in males 60 and 63 ppm, respectively.

This study investigated the appropriateness of fish consumption advisories placed on Missouri rivers. The purpose of the advisories is to warn people about potential chlordane contamination. The advisories are based on the proportion of fish in a river area that are contaminated with more than 100 ppb of chlordane. Method: Persons consuming 1 pound per week of fish for 10 of 12 weeks from contaminated river areas provided serum samples and completed a questionnaire. Controls samples were obtained from non-fish eaters. Results: The study group had higher chlordane levels than did persons not consuming fish; however, persons consuming fish from areas with the largest proportion of contaminated fish did not have any higher serum chlordane levels than persons eating fish from areas with the smallest proportion of contaminated fish. Conclusion: Health advisories based upon fish sampling techniques do not reflect the risk of exposure to chlordane.