New substances may damage ozone layer, UN environment agency warns

The United Nations Environment Programme (UNEP) has warned that a range of new chemicals appearing on the market to replace banned substances may have the potential to damage the Earth's ozone layer.

In a statement issued over the weekend as the world observed International Ozone Day on 16 September, the Nairobi-based agency said the new substances - with names like n-propyl bromide and halon-1202 - are not controlled by the Montreal Protocol, the 1987 international treaty that lists ozone-depleting substances that are to be phased out. They are used in everything from fire extinguishers to cleaning fluids.

The quantities being manufactured are at the moment believed to be small, but scientists at universities and institutes around the globe, along with UNEP researchers, are concerned that over the coming years they may be produced in ever increasing quantities.

"UNEP estimates that the ozone layer and the ozone hole over Antarctica, which so far this September is extending over 24 million square kilometres, or an area about the size of North America, will recover by 2050," the statement said. According to the agency, this is as a result of the banning and phasing out of existing, long lived, ozone-depleting chemicals such as chlorofluorocarbons (CFCs). But the emergence of these new chemicals has triggered concern that this recovery date may be significantly delayed.

"The Montreal Protocol has been a success story of which we can all be proud," says UNEP Executive Director Klaus Toepfer. "Ninety-six ozone-damaging chemicals have been banned or are being phased out and $1.3 billion have so far been contributed by developed countries to the Multilateral Fund to help developing countries implement the Protocol." That Fund was set up in the early 1990s to help developing States phase out listed substances.

UNEP is urging countries to carry out immediate scientific assessments of the new chemicals and to ban those shown to have real ozone-depleting potential. "Governments, industry and organizations like UNEP must, based on sound science, work together to devise a long-term strategy so that we know in advance the ozone-depleting potential of future chemicals before they appear on the market," Mr. Toepfer said.