When the world threw away its dangerous deodorants and fridges, scientists warned it might already be too late for the ozone layer.
But now scientists have discovered that the ill-fated ozone layer is actually slowly recovering.
The global ban on chlorine pollutants has actually contributed to this recovery but researchers warned yesterday it wasn't all good news.
Other forces at work, such as climate warming, mean ozone levels are unlikely to stabilise at pre-1980 levels.
The ozone layer, ten to 20 miles high in the Earth's stratosphere, protects every living thing against the harmful effects of ultraviolet radiation from the Sun.
In the 1980s experts became alarmed at the extent to which ozone was being destroyed by chlorine compounds used in refrigeration, air conditioning, aerosol sprays and industrial cleaners.
A "hole" in the ozone layer over Antarctica was first detected in the 1970s. Ozone depletion has been most severe at the poles, but there has been a seasonal decline of up to ten per cent at mid-latitudes - a band covering much of North America and Europe.
In 1987 the Montreal Protocol was introduced, banning the release of chlorine pollutants such as CFCs into the atmosphere.
Now ratified by more than 180 nations, the Protocol established legally binding controls on halogen gases containing chlorine and bromine.
Yesterday scientists published a new study indicating that the safeguards may be working.
The findings show that erosion of the ozone layer has slowed down. Data from satellites and ground stations, combined with information from 14 modelling studies, reveal that ozone levels have stabilised or increased only slightly in the past decade.
Natural atmospheric effects are thought to have contributed to a larger than expected recovery in northern midlatitudes. These include shifts in air temperature, the influence of the 11-year solar cycle, and an absence of major volcanic activity.
However scientists writing in the journal Nature said other factors could further threaten the ozone layer in the future.
Dr Betsy Weatherhead, from the University of Colorado at Boulder, USA, who coled the joint US-Danish study, said: "We now have some confidence that the ozone layer is responding to the decreases in chlorine levels in the atmosphere due to the levelling off and decrease of CFCs, and most of the improvements are in agreement with what we had hoped for with the Montreal Protocol in place.
"But the continuing ozone recovery process still faces a number of uncertainties."
In the future, ozone levels were likely to be dominated by air temperature, atmospheric dynamics, and the abundance of destructive trace gases, she said. The latter included significant amounts of the fertiliser product nitrous oxide, or N2O.
"In 50 years CFCs won't be the dominant factor controlling ozone," said Dr Weatherhead. "Instead, we think it will be factors like greenhouse gases, N2O, and methane."
