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China is the largest greenhouse gas emitter in the world and has committed to mitigating global warming through achieving carbon neutrality by 2060. However, detailed information on China’s historical and projected emissions of fluorinated greenhouse gases, with high global warming potentials, is lacking. Here we establish a comprehensive and up-to-date inventory of China’s fluorinated greenhouse gas emissions and find that they show an accelerating growth rate, increasing from 5.5 to 221 million tons CO2-equivalent per year from 1990 to 2019. China has become the world’s largest emitter of fluorinated greenhouse gases and contributed 93% of the global emission increase during the period 1990−2019. We find that total emissions of fluorinated greenhouse gases from China are projected to increase to 506–1356 million tons CO2-equivalent per year in 2060 if there is no regulation, which is larger than the projected CO2 emissions under China’s carbon neutrality commitment for 2060.

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The levels, spatial variation, congener profiles, impact factors, and ecological risk of polychlorinated biphenyls (PCBs) in the sediment from the Yellow River of Henan section, China, were investigated in this paper. Total concentration of 31 PCBs and seven indicator PCBs varied from ND to 1015 pg g and ND to 423 pg g, respectively. Compared with other aquatic environments around China, PCB levels in the studied area were relatively low. Spatial variations revealed that tributaries possessed higher PCB levels, in comparison to mainstream, which acted as input sources of PCBs in the mainstream. The homolog profiles were dominated by lighter PCBs (Tri-PentaCBs), contributing above 70% of total PCBs. Correlation analysis between PCB concentrations and total organic carbon indicated that local input or atmospheric deposition was the primary controls of spatial variation of PCBs. According to simple sediment quality guidelines (SQG), the risks posed by PCBs in the sediments might be negligible.

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