Exposure assessment of breast-fed infants in the Czech Republic to indicator PCBs and selected chlorinated pesticides: area-related differences.

The aim of our study was to obtain data on the exposure of breast-fed infants to polychlorinated biphenyls (PCBs) and selected organochlorine pesticides (OCPs) in different urban areas of the Czech Republic. The PCB and OCP levels were determined in 90 human milk samples collected in seven urban areas in 1999-2000 according to the WHO protocol. The estimated daily intake (EDI) was calculated for each of the analytes and compared with the respective tolerable daily intake (TDI). Significant local differences in the sum of 35 PCB congeners analyzed (total PCBs) as well as in the most prominent indicator congeners 138, 153, and 180 values were observed, with the highest levels being found in breast milk samples from mothers living in the vicinity of a former plant using PCBs in Uherské Hradiste (median and ranges 3410 and 1448-13,754 ng g(-1)lipid weight (lw)). Non-exposed mothers from the same area had about threefold lower levels (median and ranges 1073 and 757-2139 ng/g lw, respectively). The lowest levels of total PCBs were found in Telc (median and ranges 480 and 293-731 ng g(-1)lw, respectively). In all study areas, EDIs for PCBs in breast-fed infants exceeded the TDI of 0.4 microg kg(-1)bwd(-1) recommended in the Czech Republic. EDI for HCB exceeded the recommended TDI of 0.16 microg kg(-1), EDI for DDT was slightly below TDI of 10 microg kg(-1) bw d(-1) and HCHs EDI was negligible. The database of analytical results from this study was used for Bayesian modeling of breast-fed infant exposure to PCBs and OCPs during the recommended 6 months of exclusive breastfeeding.

Effect of polychlorinated biphenyls (PCBs) and 1,1,1-trichloro-2,2,-bis (4-chlorophenyl)-ethane (DDT) in follicular fluid on the results of in vitro fertilization-embryo transfer (IVF-ET) programs.

OBJECTIVE: To establish the effect of chlorinated organic compounds on fertility. DESIGN: We analyzed the influence of polychlorinated biphenyls (PCBs) and pesticides in follicular fluid on the number of fertilized oocytes, the quality of oocytes and embryos, pregnancy rate, and number of embryos cryoconserved in IVF-ET program. SETTING: Department of Gynecology and Obstetrics, Charles University, First Faculty of Medicine and General Teaching Hospital, Prague, Czech Republic. PATIENT(S): Patients from the Center of Assisted Reproduction. INTERVENTION(S): We collected the follicular fluid of 99 infertile women. MAIN OUTCOME MEASURE(S): The levels of xenobiotics in follicular fluid were examined by high-resolution mass spectrometry and gas chromatography. Correlations between the levels of xenobiotics and IVF-ET program results were statistically analyzed. RESULT(S): The PCB levels varied from 0.1 to 254.6 ng/g of fat. Levels of DDT and its metabolites varied from 0.3 to 35 228.8 ng/g of fat. A correlation was found between the number of diploid oocytes and the level of DDT, the fertilization of oocytes and level of PCB 158, and the pregnancy rate and the number of embryos cryoconserved and levels of PCB 47. CONCLUSION(S): Xenobiotics can be detected in the fat compartment of the follicular fluid. Some correlation to the IVF-ET program results was established, to a degree that might be considered of concern, although it was not statistically significant at the 5% level.

Exposure of breast-fed children in the Czech Republic to PCDDs, PCDFs, and dioxin-like PCBs.

Human milk samples from 81 mothers living in seven selected localities of the Czech Republic collected in 1999-2000 were analyzed for PCDDs, PCDFs, and dioxin-like PCBs. Significant local differences in total WHO-TEQ values were observed (median ranges: 27.8-64.6pg/g fat) with the highest level in Uherské Hradiste, but the highest PCDD-TEQ value was in Prague. Seven congeners (2,3,7,8-TCDD, 1,2,3,7,8-PeCDD, 2,3,4,7,8-PeCDF, and PCBs 118, 126, 156, and 157) cover about 90-94% of the total TEQ level. The non- and mono-ortho PCBs account for approximately 50-70% of the total TEQ levels in individual groups. The calculated median daily intake of the total TEQ for breast-fed infants ranged from 271pg/kg b.w./day in Uherské Hradiste to 117pg/kg b.w./day in Liberec and exceeded by about two orders of magnitude a tolerable daily intake (TDI) of 1-4pg/kg b.w. recommended by the WHO. Our results confirmed significant local differences in the levels of dioxins and suggest that hot spot locations might exist within the country.