Survey on levels of PCDDs, PCDFs, and non-ortho Co-PCBs in soil and sediment from a high cancer area near a batch-type municipal solid waste incinerator in Japan

Polychlorinated biphenyls and risk of metabolic syndrome and comparison with the risk of diabetes: A systematic review and meta-analysis

With the increasing incidence of metabolic syndrome (MetS) worldwide and no consistent results on PCBs and MetS. A meta-analysis to explore their relationship was conducted. Given the high correlation and overlap of MetS with diabetes, analysis of diabetes risk, was used as a supplement to compare with MetS. Seven studies included MetS, 15 studies for diabetes, and one study included both outcomes. It was found that PCBs may not be a risk factor for MetS, but their high heterogeneity indicates that they are under-represented. In addition, our results showed that total PCBs might be a protective factor against diabetes. In the whole blood subgroup, which can reflect the accumulation of more than one body load, heterogeneity was reduced, and its OR value suggested that PCBs increased the risk of MetS in the whole blood biomaterial. DL-PCBs were positively associated with MetS and diabetes, while NDL-PCBs were negatively associated with diabetes. In the subgroup analysis of PCBs homologs, DL-PCB-126 and DL-PCB-118 were risk factors for MetS and diabetes, respectively. In addition, PCB-153 and 180 showed a dose-response relationship between them and diabetes mellitus, respectively. The results of total analysis of MetS and diabetes mellitus and subgroup analysis of PCBs were mixed, and this reason might be attributed to the different mechanisms of action and effect sizes of different PCBs, so based on subgroup results and in vivo and in vitro experiments, we considered PCBs to be a risk factor for MetS and diabetes. Due to various reasons, there are still many shortcomings in the evaluation of PCBs impact on human health, and more high-quality research are needed to further explore the role of PCBs of different species and congeners in MetS and diabetes.

Polybrominated diphenyl ethers in surface sediments from fishing ports along the coast of Bohai Sea, China

The distribution, congener patterns, possible sources, and ecological risks of polybrominated diphenyl ethers (PBDEs) were investigated in the surface sediments of 20 fishing ports along the coast of Bohai Sea. PBDEs are widespread pollutants in fishing ports, and the total concentrations of 14 PBDEs (∑₁₄PBDEs) are 4.23-20.59 ng/g with a mean value of 12.56 ng/g. BDE-209 was the dominant congener. The fishing ports with high PBDE concentrations were located near Liaohe River, Haihe River, manufacturing plants of BFRs near Laizhou Bay, and tipping areas of marine garbage. BDE-209 and BDE-47 were the most important congeners that discriminate PBDE pollution. The possible sources of PBDEs included the input of commercial mixtures of penta-BDE, octa-BDE, and deca-BDE, the debromination of BDE-209, and the atmospheric transport of the low brominated diphenyl ethers. The ecological risks in surface sediments were attributed to the congeners of tetra-BDE, penta-BDE, and deca-BDE with low or medium levels.

Transformation of PBDE mixtures during sediment transport and resuspension in marine environments (Gulf of Lion, NW Mediterranean Sea)

Polybromodiphenyl ethers (PBDEs) in superficial sediments from the Gulf of Lion were studied. They were largely predominated by BDE 209 (98.7% of all PBDEs) indicating that the main source of these pollutants was the commercial mixture deca-BDE. This compound and the less brominated BDE exhibited a southwestward decreasing concentration gradient following the dominant marine currents and bottom relief, e.g. the Mud Belt, the submarine canyons and the Open Continental Slope. All PBDEs exhibited statistically significant correlations confirming the common origin. However, a progressive transformation of the dumped BDE 209 was identified showing a depletion paralleled by increases of the less brominated BDEs (from 8.6% to 22%). These less brominated compounds were accumulated at about 100-140 km away from the Rhone prodelta, e.g., at the end of the submarine canyons, evidencing that these transformation compounds can be accumulated at long distances from the dumping sites in the marine system.

Global contamination of coplanar polybrominated/chlorinated biphenyls (Co-PXBs) in the market fishes from Japan

Polybrominated chlorinated biphenyls (PXBs, X=Br, Cl) are a group of environmental contaminants that have not been studied previously. The introduction of the second halogen to the biphenyl backbone increases the number of possible congeners to more than 9000. Only a limited number of PXBs are commercially available. In order to determine the occurrence of these compounds in environmental matrices, an isotope dilution HRGC/HRMS method for determination of five co-planar polybrominated/chlorinated biphenyls (Co-PXBs) in biota was developed. The method detection limit for these compounds ranged between 0.05 and 0.5 pg/g for 4'-monobromo-3,3',4,5-tetrachlorobiphenyl and 3',4',5'-tribromo-3,4-dichlorobiphenyl, respectively. Concentrations of five co-planar polybrominated and chlorinated biphenyls in eighteen different fish fillets from Japanese markets ranged between 4 and 46 pg/g wet weight for mink whale and young yellow-tail fish. These values are substantially lower than those reported for Co-PCBs; however, it should be noted that due to the unavailability of standards, identification and quantification of all the isomers was not possible.

Source identification of PCDD/Fs in agricultural soils near to a Chinese MSWI plant through isomer-specific data analysis

Isomer-specific data were investigated in order to identify the sources of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in agricultural soils, including Fluvo-aquic and paddy soils, in the vicinity of a Chinese municipal solid waste incineration (MSWI) plant. Homologue and isomer profiles of PCDD/Fs in soils were compared with those of potential sources, including combustion sources, i.e., MSWI flue gas and fly ash; and the impurities in agrochemicals, such as the pentachlorophenol (PCP), sodium pentachlorophenate (PCP-Na) and 1,3,5-trichloro-2-(4-nitrophenoxy) benzene (CNP). The results showed that the PCDD/F isomer profiles of combustion sources and agricultural soils were very similar, especially for PCDFs, although their homologue profiles varied, indicating that all the isomers within each homologue behave identically in the air and soil. Moreover, factor analysis of the isomer compositions among 33 soil samples revealed that the contamination of PCDD/Fs in agricultural soils near the MSWI plant were primarily influenced by the combustion sources, followed by the PCP/PCP-Na and CNP sources. This implication is consistent with our previous findings based on chemometric analysis of homologue profiles of soil and flue gas samples, and identifies PCP/PCP-Na as an additional important source of PCDD/Fs in the local area. This makes the similarities and differences of isomer profiles between Fluvo-aquic and paddy soils more explainable. It is, therefore, advisable to use isomer-specific data for PCDD/F source identifications where possible.

PCDD/F concentrations of agricultural soil in the vicinity of fluidized bed incinerators of co-firing MSW with coal in Hangzhou, China

The concentrations of 17PCDD/F congeners as well as tetra- to octa-homologues were determined in 33 soil samples collected within a radius of 7 km from a municipal solid waste (MSW) incineration plant that is equipped with three fluidized bed incinerators (FBIs) of co-firing MSW with coal in Hangzhou, China. The total PCDD/F concentrations ranged from 0.39 to 5.04 pg I-TEQ g(-1) (54-285 pg g(-1)), with an average and a median value of 1.22 and 0.84 pg I-TEQ g(-1) (105 and 86 pg g(-1)), respectively. A systematic decrease of PCDD/F levels was observed with the increasing distances and with the decreasing downwind frequencies from the plant. The comparisons of homologue and congener patterns and multivariate analysis of soil and flue gas samples strongly indicated that most of the soil samples were influenced by the FBIs. Apart from the incineration plant, historical PCDD/F emissions of hazardous waste incinerator (HWI) and motor vehicles as well as the application of 1,3,5-trichloro-2-(4-nitrophenoxy) benzene (CNP) seemed to play an important role in soil samples adjacent to these potential sources.