Researchers from the University of East Anglia have reported the existence of four previously unknown ozone-depleting compounds.
Nature Geoscience has published a paper reports the detection and quantification of a further three CFCs and one HCFC.
So far, seven types of CFC and six types of HCFC have been shown to contribute to stratospheric ozone destruction, the researchers say.
The researchers examined unpolluted air samples collected in Tasmania between 1978 and 2012, and extracted snow in Greenland in 2008 that showed that all four compounds started to emerge in the atmosphere in the 1960s. Two of the compounds continue to accumulate in the atmosphere. The authors report that while small, a combined 74,000 metric tons compared to 1 million metric tons annually for the other four compounds, they run counter to global protocols.