CCl 4 emissions in eastern China during 2021-2022 and exploration of potential new sources.

According to the Montreal Protocol, the production and consumption of ozone-layer-depleting CCl 4 for dispersive applications was globally phased out by 2010, including China. However, continued CCl 4 emissions were disclosed, with the latest CCl 4 emissions unknown in eastern China. In the current study, based on the atmospheric measurements of ~12,000 air samples taken at two sites in eastern China, the 2021-2022 CCl 4 emissions are quantified as 7.6 ± 1.7 gigagrams per year. This finding indicates that CCl 4 emissions continued after being phased out for dispersive uses in 2010. Subsequently, our study identifies potential industrial sources (manufacture of general purpose machinery and manufacture of raw chemical materials, and chemical products) of CCl 4 emissions.