Temporal and spatial variations in atmospheric unintentional PCB emissions in Chinese mainland from 1960 to 2019

[摘要] Polychlorinated biphenyls (PCBs) are nowadays mainly unintentionally produced, since their use and manufacture has been banned. PCBs, especially those dioxin-like compounds, have been proven harmful to ecosystems and human health. Detailed information about thespatiotemporally distribution of unintentionally produced PCBs (UP-PCBs) iscrucial for understanding the environmental fate and associated healthrisks. However, research estimating UP-PCBs emission in China islimited. In this study, a source-specific and year-varying emission factor (EF) dataset was used to compile provincial emissions of 12 dioxin-like UP-PCBs congeners for 66 sources in the Chinese mainland from 1960 to 2019. In addition to that, emissions for 2019 were allocated into 0.1 ∘ × 0.1 ∘ grids. The results indicated that historical nationalUP-PCBs emission represented an increasing trend until around 1995 and thenshowed an overall decreasing trend from 1995 to 2019. Cement production wasthe largest UP-PCBs emission source in the Chinese mainland. Geographically,East and North China contributed the largest UP-PCBs emission across the Chinesemainland. High emission densities occurred mainly in the denselypopulated and well-developed regions such as Yangtze River Delta UrbanAgglomeration and Pearl River Delta. Furthermore, highly positivecorrelations of emission densities with population and GDP densities wereidentified.

[学科分类] 医学（综合）