Presence of novel and legacy flame retardants and other pollutants in an e-waste site in China and associated risks.

Electrical and Electronic Equipment (EEE) residues and their management have been widely identified as potential sources of plasticizers and flame retardants to the environment, especially in non-formal e-waste facilities. This study evaluates the distribution, partitioning and environmental and human impact of organophosphate esters (OPEs), legacy polychlorinated biphenyls (PCBs), polybromodiphenyl ethers (PBDEs) and organochlorine pesticides (OCPs) in the e-waste recycling area of Baihe Tang village, in the Qingyuan county, Guangdong province, China. A plastic debris lump accumulated in a small pond during years was identified as the main source of pollution with ∑pollutants of 8400 µg/g dw, being OPEs the main contaminants detected, followed by PBDEs. This lump produced the contamination of water, sediments, soils and hen eggs in the surrounding area at high concentrations. Plastic-water and water-sediment partitioning coefficients explained the migration of OPEs to the water body and accumulation in sediments, with a strong dependence according to the KOW. Triphenyl phosphate (TPhP), tricresyl phosphate (TCPs) and high chlorination degree PCBs produced a risk in soils and sediments, considering the lowest predicted no effect concentration, while the presence of PCBs and PBDEs in free range hen eggs exceeded the acceptable daily intake. OCPs were detected at low concentrations in all samples. The presence of organic contaminants in e-waste facilities worldwide is discussed to highlight the need for a strict control of EEE management to minimize environmental and human risks.

Characterizing the Influence of Metabolism on the Halogenated Organic Contaminant Biomagnification in Two Artificial Food Chains Using Compound- and Enantiomer-Specific Stable Carbon Isotope Analysis.

Two artificial food chains, food tiger barb-oscar fish and food tiger barb-redtail catfish, were established in the laboratory. The species-specific biotransformation of ortho, para'-dichlorodiphenyltrichloroethane, 12 polychlorinated biphenyl, and five polybrominated diphenyl ether congeners were characterized by measuring the compound- and enantiomer-specific stable carbon isotope composition (δ13C), enantiomeric fraction of the chiral chemicals, and metabolites in the fish. Compound- and enantiomer-specific biotransformations were revealed by the alteration of δ13C and EF in both predator fish species. Significant correlations between the carbon stable isotope signatures and the depuration rates and biomagnification factors (BMF) were observed. Chemicals that exhibited changes in δ13C during the experiment have higher kd and lower BMF values than those with unchanged δ13C. Specifically, the difference between the predicted BMF based on the log Kow and the measured BMF, ΔBMF, was significantly positively and linearly correlated to the change in the δ13C (expressed by Δδ13C/δ13Cinitial, the percentage of Δδ13C: δ13Cending-δ13Cinitial to the initial δ13Cinitial) in both food chains. These results indicated that the impact of metabolism on the bioaccumulation potential of organic contaminants can be predicted by the stable carbon isotope fractionation of chemicals in the fish.

Level changes and human dietary exposure assessment of halogenated flame retardant levels in free-range chicken eggs: A case study of a former e-waste recycling site, South China.

To assess the impacts of e-waste regulations on environmental pollution, we built on a previous study from 2010 to investigate the levels and human dietary exposure of halogenated flame retardants (HFRs) in free-range chicken eggs from Baihe village in 2013 and 2016. The concentrations of PBDEs, PBBs, HBCDs, and DBDPE showed a significant decrease (p<0.05) from 2010 to 2013/2016, suggesting the efficacy of regulatory policies. The relative contribution of BDE209 were higher in 2013 and 2016 than in 2010, accounting for 67.8%, 61.4%, and 27.7%, respectively. The concentration ratios of PBB209:PBB153 were much lower in 2013 (1.51) and 2016 (1.32) than in 2010 (29.5). These observed different profiles likely due to the different environmental behaviors of HFRs (e.g. the different atmospheric migration abilities of PBDE congeners and degradation of PBB209). Our exposure estimates suggested high dietary intake of HFRs via home-produced eggs. As for PBDEs, considering the worst situation (highly polluted eggs were consumed), the margin of exposure (MOE) of BDE99 for both adults and children were 1.5 and 0.3 in 2013, and 1.1 and 0.2 in 2016, respectively, which were below 2.5. According to the CONTAM panel, an MOE larger than 2.5 indicates no health concern. Therefore, these MOE values represent a significant potential health concern due to the adverse impacts of PBDEs on human neurodevelopment and fertility.

Hepatic ethoxyresorufin-O-deethylase induction in the common kingfisher from an electronic waste recycling site.

The health effects of exposure to electronic waste (e-waste)-derived pollutants are an important issue. The authors explored the association between the hepatic levels of e-waste-derived halogenated contaminants (including polychlorinated biphenyls [PCBs], polybrominated diphenyl ethers [PBDEs], and polybrominated biphenyls [PBBs]) and hepatic ethoxyresorufin-O-deethylase (EROD) activity of the common kingfisher (Alcedo atthis) from an e-waste site and 2 reference sites in South China. The summed concentrations of PCBs, PBDEs, and PBBs ranged from 620 ng/g to 15 000 ng/g, 25 ng/g to 900 ng/g, and 14 ng/g to 49 ng/g wet weight, respectively, in the kingfishers from the e-waste site, and these values were significantly greater (2-3 orders of magnitude) than those obtained at the 2 reference sites. Correspondingly, significant hepatic EROD induction was observed in the kingfishers from the e-waste site compared with the reference sites. The EROD activity was significantly correlated to the levels of most of the PCB and PBDE congeners examined as well as PBB 153, suggesting that EROD induction may be evoked by these e-waste-derived pollutants. Environ Toxicol Chem 2016;35:1594-1599. © 2015 SETAC.

Aquatic bioaccumulation and trophic transfer of tetrabromobisphenol-A flame retardant introduced from a typical e-waste recycling site.

While the flame retardant chemical, tetrabromobisphenol-A (TBBP-A), has been frequently detected in the environment, knowledge regarding its species-specific bioaccumulation and trophic transfer is limited, especially in the highly contaminated sites. In this study, the components of an aquatic food web, including two invertebrates, two prey fish, and one predator fish, collected from a natural pond at an electronic waste (e-waste) recycling site in South China were analyzed for TBBP-A, using liquid chromatography-tandem mass spectrometry. The aquatic species had TBBP-A concentrations ranging from 350 to 1970 pg/g wet weight, with higher concentrations in the invertebrates relative to the fish species. Field-determined bioaccumulation factors of TBBP-A in the two aquatic invertebrates were nearly or greater than 5000, suggesting that TBBP-A is highly bioaccumulative in the two species. The lipid-normalized concentrations of TBBP-A in the aquatic species were negatively correlated with the trophic levels determined from stable nitrogen isotope (δ(15)N) (r = -0.82, p = 0.09), indicating that this compound experienced trophic dilution in the current food web.

[Identification of Pterocephalus hookeri].

OBJECTIVE: To study the identification method of Pterocephalus hookeri. METHOD: The microscopical, Physicochemical and TLC methods were used. RESULT AND CONCLUSION: The convenient and effective identification methods for P. hookeri were established, which provide basis for its quality standard and development.