Environmental contamination and human exposure to PBDEs and other hazardous chemicals arising from informal e-waste handling

摘要

A method was developed and validated for GC/MS analysis of PBDEs in a variety of matrices (soil, dust, sediment, and 10 types of foodstuffs), represented by a total of 313 samples. Extensive environmental contamination by PBDEs is shown to arise as a result of improper e-waste handling in Guiyu, China, with open burning and circuit boards shredding operations identified as the most significant sources of PBDEs to soil and sediment. Elevated concentrations of selected key pollutants, including legacy and novel brominated flame retardants (NBFRs), polychlorinated biphenyls (PCBs), and metals/metalloids, were detected in a number of dietary samples from Taizhou e-waste recycling sites, confirming the hypothesis that improper e-waste handling is an important source of toxic contaminants to locally produced foods. Human exposure, of both adults and children, to key pollutants via diet was estimated, with results suggesting that children are particularly exposed to a range of toxic substances through a locally-sourced diet. This was especially evident in the case of PCBs, PBDEs, cadmium, and lead. Concentrations of, and/or routes of human exposure to, several contaminants (e.g., PBDEs in duck eggs, and compound-specific NBFRs in diet originating from Taizhou) are reported here for the first time. Application of a simple pharmacokinetic model to predict human body burden of PBDEs (based on estimated dietary intake) provided predicted PBDE body burdens that compared satisfactorily in most instances with those reported elsewhere in blood of adults from Taizhou e-waste sites.