Researchers have discovered four new man-made gases that are harming the ozone layer.
Similar gases were banned under the 1987 Montreal Protocol treaty, Reuters reported.
The researchers were looking for the industrial source of trace chemicals found in Greenland's ice and in air samples taken in Tasmania. The team found three types of CFCs (chlorofluorocarbon) and one HCFC (hydrochlorofluorocarbon).
Lead author Johannes Laube of the University of East Anglia in England told Reuters that he does not believe the current concentration levels are a threat to the ozone.
"Our research has shown four gases that were not around in the atmosphere at all until the 1960s which suggests they are man-made," Laube told the BBC.The scientists believe 74,000 metric tons of the chemicals have been released into the atmosphere. None of these chemicals were present in the 1960s. It is unclear I the emission of these chemicals is illegal under the Montral Protocal, Reuters reported.
"We hope to tighten the loopholes," Laube told Reuters.
A hole in the Earth's ozone formed over Antarctica in the 1980s, but bans on a number of chemicals have it on track to recover over the next 50 years.
One of the newly-discovered CFC is rapidly increasing in concentration. Studies suggest the CFCs are produced in the world's global hemisphere and are swept south by winds.
"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, told Reuters.
"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," he said.
"Laube said the gases are also likely to be powerful greenhouse gases, albeit in tiny amounts. CFCs are often thousands of times more powerful than carbon dioxide at trapping heat in the atmosphere," Reuters reported.
