Four new man-made gases may be undermining the recovery of the ozone hole over Antarctica, researchers revealed in a scientific report published in Nature Geoscience.

As early as 1985, British scientists discovered a huge hole in the ozone over Antarctica. Chlorofluorocarbon (CFC) gases, widely used in refrigeration and products like hairsprays and deodorants, were found linked to the formation of the hole. The production of CFC gases has been restricted since then.

Researchers from the University of East Anglia discovered evidence of four new gases that can destroy ozone, but the precise origin of these extremely potent greenhouse gases remains unknown.

In this new research, they analysed air samples captured since the mid-1970s in several ways and different places, including Greenland, Tasmania and Europe.

Researchers found three new CFCs and one hydrochlorofluorocarbon (HCFC), all of which were identified for the first time.

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

Laube said he is particularly concerned that the atmospheric concentrations of two of the new compounds, while low now, are actually accelerating. Both of them will take decades to break down in the atmosphere, meaning their impact on ozone and climate change is long-lived.