Unexplained increases in five atmospheric CFCs raise concerns

New measurements have revealed rising levels of five potent ozone-depleting gases, despite rigorous international controls over their production. A cross-disciplinary team reported a 2.6-fold increase in the emissions of five regulated chlorofluorocarbons (CFCs) between 2010 and 2020 , which could undermine the progress of current environmental targets.

CFCs are the fully-halogenated derivatives of simple hydrocarbons and their use was formerly widespread as refrigerants and aerosol propellants. Their devastating environmental impact, most notably causing the hole in the ozone layer, led to tight global regulation under the Montreal Protocol.