EU environment watchdog highlights ozone risks

A report from Europe's environmental watchdog may lead to new regulation aimed at curbing rising levels of ground-level ozone before it ends up damaging crop yields and human health.

Although the study from the European Environmental Agency (EEA) found that the region had managed to cut the emission of gases that lead to ozone creation by 20 to 30 per cent between 1995 and 2005, it also indicated that ground-level ozone pollution levels "do not show any downward trends". In fact, measurements from a site in Ireland showed that emissions had increased by six per cent and are expected to rise further.

This situation is a problem because ozone is both a greenhouse gas and an air pollutant, and rising levels could result in poorer crop yields, damage to natural ecosystems and negative effects on human health. The gas's effect on people's respiratory systems has been linked to premature death, particularly among asthmatics, the young and elderly.

As a result, the report concluded that there were "good arguments for integrating ozone abatement into local and regional, but also global strategies and measures addressing air pollutants and greenhouse gas emissions simultaneously".

These arguments are reinforced by the fact that annual ozone levels are greatly influenced by variations in weather conditions. Higher temperatures, more frequent heat waves, changes in rainfall distribution and reduced levels of cloudiness all boost production because ozone forms when sunlight reacts with pollutants in the air from sources such as vehicle exhausts and heavy industry. Such considerations mean that predicted increases in average temperatures as a result of climate change could lead to higher ozone concentrations in many areas of Europe.

The situation is also being exacerbated by the fact that ozone is being imported into Europe via intercontinental transport. Such activity accounts for between 10 and 30 per cent of surface ozone levels in western Europe and Scandinavia and less than 10 per cent in central Europe.

The EEA study was undertaken using data from 198 rural air quality measuring stations in 18 countries, including the UK, Scandinavia and central Europe.

But the report warned that the narrowness of geographical coverage combined with the fact that another five to 10 years of "stable" observations from the same stations are required to support a "robust" analysis, mean that the results should be treated with some "caution".