(Guardian)

Dozens of mysterious ozone-destroying chemicals may be undermining the recovery of the giant ozone hole over Antarctica, researchers have revealed.

The chemicals, which are also extremely potent 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."