Newly discovered gases destroying ozone layer over Antarctica

Dozens of ozone-destroying chemicals may be undermining the recovery of the ozone hole over Antarctica, researchers say.

The chemicals, which are also greenhouse gases, may be leaking from industrial plants or being used illegally, contravening the Montreal protocol which began banning the ozone destroyers in 1987. Scientists said the finding of the chemicals circulating in the atmosphere showed "ozone depletion is not yesterday's story".

Until now, a total of 13 chlorofluorocarbons and hydrochlorofluorocarbons were known to destroy ozone and are controlled by the Montreal protocol, regarded as the world's most successful environmental law. Scientists have now identified and measured four previously unknown compounds and warned of the existence of many more.

"There are definitely more out there," said Dr Johannes Laube of the University of East Anglia. "We have already picked up dozens more. They might well add up to dangerous levels, especially if we keep finding more."

Laube and his colleagues are in the process of analysing the dozens of new compounds.

Laube is concerned that the atmospheric concentrations of two of the new compounds, while low, are rising.

"They are completely unimpressed by the Montreal protocol," Laube said. "There are quite a few loopholes in the protocol and we hope some of these are tightened. But the good news is that we have picked up these [four] early."