There's apparently a new generation of ozone-damaging gases in the atmosphere.

Scientists out of the University of East Anglia in England have reported four new man-made gases known to damage the earth's protective layer of ozone, even though the production on almost all similar gases has been outlawed since 1987 under the United Nation's Montreal Protocol.

A study published in the journal Nature Geoscience indicates experts are working to find industrial sources of the new gases, which could be linked to operations that make pesticides and refrigerants.

The gases were detected first in Greenland and then Tasmania, Australia -- an indication they were produced and released somewhere in the northern hemisphere and then drifted southward.

Research planes, taking air samples around the world, may provide the best chance of detecting the gas origins, said able to find the sources, Johannes Laube of the University of East Anglia in England, told Reuters.

He noted three types of the detected gases are CFCs, or, chlorofluorocarbons, while one is an HCFC, hydrochlorofluorocarbon.

"While these newly discovered gases can, in theory, cause some damage to the ozone layer, their combined abundance is over 500 times smaller than that of the main ozone-destroying compounds in the 1990s," Martyn Chipperfield, a professor of atmospheric chemistry at the University of Leeds, was also quoted in the Reuters report. "These new observations do not present concern at the moment, although the fact that these gases are in the atmosphere and some are increasing needs investigation,"

While Laube agreed the gas concentrations in the air "are not yet a threat to the ozone layer," he added the suspect gases, even if only present in tiny amounts, may nonetheless prove powerful greenhouse gases, since CFCs can be thousands of times more powerful than carbon dioxide at trapping heat in the atmosphere.

The ozone layer shields the planet from damaging ultra-violet rays, which can cause skin cancer and other health problems such as eye cataracts.

In total, the study says, more than an estimated 74,000 tons of the four gases had been released into the atmosphere.

Records show none of the four were detected in samples taken from Greenland's ice before the 1960s.

Laube said the science team doesn't know if the emissions of the new gases were illegal, since the Montreal Protocol has some exemptions.

"We hope to tighten the loopholes," he said.