Levels Of dl-PCBs Research Articles

Longitudinal increases in PCDD/F and dl-PCB concentrations in human milk in northern China

There is a dearth of information on the temporal changes in polychlorinated dibenzodioxin/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) contamination, in both environmental and biological specimens, in China. We compared the concentrations of PCDD/Fs and dl-PCBs in human milk collected in Shijiazhuang, Hebei Province, in northern China in 2002 (n=30) and 2007 (n=20). The level of PCDD/Fs and dl-PCBs showed an increasing trend. The mean concentrations of PCDD/Fs plus dl-PCBs were 4.47TEQ pgg−1 fat and 6.24TEQ pgg−1 fat in human milk from Shijiazhuang in 2002 and in 2007, respectively. Based on statistical analysis of questionnaire data collected by in-person interviews with mothers, we found positive correlations between consumption of sea fish and PCDFs. The PCDDs, PCDFs, PCDD/Fs, and PCDD/Fs plus dl-PCBs levels in individuals consuming greater amounts of sea fish were higher than those consuming less sea fish, both with and without adjustments for potential confounding factors. Among 17 congeners of PCDD/Fs, the 2,3,7,8-TCDF, 1,2,3,7,8-PeCDF, 2,3,4,7,8-PeCDF, 1,2,3,4,7,8-HxCDF, 1,2,3,6,7,8-HxCDF, and 2,3,4,6,7,8-HxCDF congener concentrations in 2007 increased 134%, 55%, 53%, 57%, 65% and 130% when compared to 2002 levels, respectively. The 2007dl-PCB congener levels were greater than those of the 2002 samples, with the exception of PCB81 and PCB77. Specifically, PCB105, PCB114, PCB118, PCB123 and PCB156 had increased greater than twofold from 2002 to 2007. Continuous surveillance of PCDD/F and dl-PCB levels in human milk is needed to accurately evaluate both environmental contamination and the human health risk to neonates in China.

Unintentionally produced dioxin-like polychlorinated biphenyls during cooking

The formation and distribution of dioxin-like polychlorinated biphenyls (dl-PCBs) during cooking was investigated. Concentrations of dl-PCBs in liquid residues, cooked beef, and oil fumes generated during heating were determined by isotope dilution HRGC/HRMS. Although the levels of dl-PCBs in well-done beef were lower compared with those of raw beef, relatively high concentrations of dl-PCBs were detected in the oil fumes produced during heating. This suggests that dl-PCBs in raw beef may have volatilized into the oil fumes during the cooking process. Sucralose and chloropropanols contained in raw materials may have resulted in increased dl-PCB concentrations and the level of toxic equivalents (TEQ) in the oil fumes produced under high temperature during cooking. Concentrations of dl-PCBs did not vary greatly in cooked beef, except when higher levels of chloropropanols were presented in the uncooked raw materials. Results indicate that sucralose and chloropropanols may promote the formation of dl-PCBs during the cooking process. The newly produced dl-PCBs from raw beef cooking were mainly present in oil fumes, which gave rise to high levels of TEQ in oil fumes.

Levels of dioxins and polybrominated diphenyl ethers in human milk from three regions of northern China and potential dietary risk factors

Human milk samples were collected from 50 breast-feeding mothers in Shijiazhuang, 60 in Tianjin and 48 in Yantai from November 2006 to April 2007. The three areas are located in northern China. We selected randomly 20 samples from each area for detection of polychlorinated dibenzodioxins/frans (PCDD/Fs), polycholorinated biphenyls (dl-PCBs) and polybrominated diphenyl ethers (PBDEs) by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). Our results show the average concentrations of PCDD/Fs plus dl-PCBs were 6.24 TEQ pg g −1fat, 7.54 TEQ pg g −1fat and 6.69 TEQ pg g −1 fat in human milk from Shijiazhuang, Tianjin and Yantai, respectively. The average concentrations of PBDEs were 3.71 ng g −1 fat, 3.42 ng g −1 fat and 4.16 ng g −1 fat in human milk from Shijiazhuang, Tianjin and Yantai, respectively. Among congeners of PBDEs, the high and low brominated congeners BDE209, BDE207, BDE197, BDE153, BDE15, BDE28 and BDE47 were the predominant PBDE congeners, accounting for 91%, 90% and 84% of total PBDEs in samples from Shijiazhuang, Tianjin and Yantai, respectively. Based on the results of an in-person interview of mothers using a questionnaire, freshwater fish consumption was found to correlate with total mono-ortho dl-PCBs (mo-PCBs) and sea fish consumption was found to correlate with total non-ortho dl-PCBs (no-PCBs) of human milk in these areas. However, no correlation was found between concentrations of total PBDEs and total TEQ of PCDD/Fs plus dl-PCBs and food consumption. Continuous surveillance on dioxins and dl-PCBs levels in human milk is needed to correctly evaluate both the environmental impact and human health risk in China.

Organochlorine pollutants in European eel ( Anguilla anguilla L.) from Poland

The purpose of the current paper is to report the levels of OC pesticides (∑HCHs, HCB, ∑DDTs), marker PCBs, PCDD/Fs, and dl-PCBs in the muscle tissue of European eel, Anguilla anguilla (L. ), collected in the Vistula and Szczecin lagoons (Poland), and in the local market. The results obtained were evaluated according to maximum limits adopted by EU, and some national legislatures. The intake of organochlorine contaminants from the consumption of eel from Polish waters is also estimated. The residues of tested contaminants ranged between: 0.6 and 6.0 ng g −1 ww for ∑HCHs; 9.8 and 273.9 ng g −1 ww for ∑DDTs; 0.4 and 23.8 ng g −1 ww for HCB; 4.0 and 533.9 ng g −1 ww ∑ 7PCBs; 0.72 and 8.14 pg-WHO-TEQ g −1 ww for ∑PCDD/F/DL-PCBs. The levels of OCPs, and PCDD/F/dl-PCBs in the muscle tissues of eels captured in the Vistula and Szczecin lagoons were compliant with European regulations.

Effects of Dioxins, PCBs, and PBDEs on Immunology and Hematology in Adolescents

Dioxins and PCBs are environmental pollutants, proven to be immunotoxic. In the period 1987-1991 a cohort of mother-baby pairs was initiated to detect abnormalities in relation to dioxin levels in the mother's milk. At birth and at follow-up at 8-12 years, immunological and hematological effects were seen, prompting us to perform a new follow-up during adolescence. In addition, we assessed the immunological and hematological parameters in relation to current levels of PBDEs and PCBs. In the Netherlands, the pre- and postnatal exposure to dioxins have been studied prospectively since 1987. Venapuncture was performed to assess hematological (Hemoglobin, thrombocytes, thrombopoietin) and immunological (leukocytes, leukocyte differentiation) parameters and the current serum levels of dioxin, dioxinlike (dl)-PCBs and PBDEs. A decrease in the number of polymorphic neutrophils was found in adolescents with higher dl-PCBs in their serum (p = 0.021). No relation with total leukocytes, thrombocytes, hemoglobin, or thrombopoietin levels was seen. Similarly, we found no relation between prenatal, nor current dioxin levels and the hematological and the immunological parameters determined. The SigmaPBDEs were negatively associated with the number of lymphocytes (p = 0.01) and positively associated with the hemoglobin concentration (p = 0.003). These effects on the innate immunity by current levels of dl-PCBs and on the adaptive immunity by PBDEs are disconcerting, especially as the dl-PCB (0.04-7.8 WHOTEQ pg/g lipid, mean: 2.2 WHOTEQ pg/g lipid) and SigmaPBDE levels (mean 14.0 ng/g lipid, including one outlier with a sum of 73.6 ng/g lipid) were not high.

A national survey of polychlorinated dioxins, furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in human milk in China

The study examined the levels of dioxin-like compounds in 24 pooled samples that were comprised of 1237 individual human milk samples from 12 provinces of China. The samples were taken in different regions to evaluate the body burden of these contaminants and assess their health risk to breast-feeding infants of China. The pooled samples were analyzed for 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) congeners. The population of the provinces involved in this study accounts for approximately 50% of the total Chinese population. The range of upper-bound total-TEQ in samples was from 2.59 pg TEQ g −1 lipid to 9.92 pg TEQ g −1 lipid with a mean of 5.42 pg TEQ g −1 lipid and a median of 5.11 pg TEQ g −1 lipid. PCDD/Fs-TEQ and total-TEQ in human milk from rural areas were lower than those from urban areas. The positive correlations were found between total-TEQ level in human milk and the consumption of aquatic food and meat respectively. The mean estimated daily intake of PCDD/Fs and dl-PCBs by infants was 28.0 pg TEQ kg −1 bw per day with a range from 14.2 pg TEQ kg −1 bw per day to 48.6 pg TEQ kg −1 bw per day. In the study, both the TEQ body burden of the sample population and estimated daily TEQ intake of breast-feeding infants were lower than those of developed countries. Continuous surveillance on PCDD/Fs and dl-PCBs levels in human milk is needed to correctly evaluate both the environmental impact and human health risk in China.

High variation of PCDDs, PCDFs, and dioxin-like PCBs ratio in cooked food from the first total diet survey in Taiwan

This study determined the levels of polychlorinated dibenzo- p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), and dioxin-like polychlorinated biphenyls (dl-PCBs) in 240 individual food samples, belonging to 37 different foodstuffs in first total diet study (TDS) in Taiwan. The foods were collected from markets located in eight cities or counties around Taiwan. The food was cooked in a laboratory according to recipes typically used in Taiwan. In this study, PCDD/Fs were lower than the limits proposed by the European Union (EU) regulation for commercialized food, except for a notable PCDD/Fs level in ducks (3.660 pg WHO-TEQ/g, fat) obtained from central Taiwan. We hypothesize the duck meat might be probably polluted via emission of a fly ash recycling plant located near the duck farms. In addition to fish, most foods had high PCDD/Fs to dl-PCBs ratio. Needle fish and sea perch had relatively lower PCDD/Fs and dl-PCBs levels compared with those in other fish. Data from this study can be utilized for further consideration about dietary intake.