Avoiding harmful ozone pollution this summer

To date, the highest concentrations of ozone this summer were on 25 and 26 July in the afternoon and evening. Belgium, western Germany, the Paris region and northern France as well as the north of Italy were particularly affected.

Excessive ground-level ozone can cause breathing problems, trigger asthma, reduce lung function and cause lung diseases. The mortality rate rises with increases in ozone exposure, according to several European studies. Unlike ozone in the stratosphere, which protects us from ultraviolet radiation, high levels of ground-level or ‘tropospheric’ ozone can also damage plants, reducing crop yields and forest growth, and also damage buildings and monuments.

Ground-level ozone is not directly emitted into the atmosphere but is formed from chemical reactions following the release of various  ‘precursor pollutants’ from a wide variety of sources: for example, fossil fuel combustion, road transport, refineries, solvents, vegetation, landfills, wastewater, livestock, and forest fires.

The reactions that create ozone are catalysed by heat and sunlight – so it is a particular problem in the summer months, and southern Europe typically has much higher levels of ozone than the north.

Staying safe from poor air quality

You can find up-to-date information on ground level ozone concentrations across the pan-European region at the EEA’s Ozone Web. The site gives hourly ground level ozone concentrations for the current situation and recent episodes, based on up-to-date measured air quality data. The website provides data from around 2 000 monitoring sites, allowing anyone to check air quality in a specific region or across Europe.

Children, the elderly, asthma sufferers and others with respiratory illnesses are most vulnerable. If ozone levels are very high, it is advisable for these groups to avoid spending a lot of time outdoors. Ozone levels are usually higher in the afternoon, so vulnerable people may avoid the higher levels of pollution by working or exercising outdoors in the mornings or evenings.

Most Europeans exposed to ozone pollution

Although emissions of precursor pollutants have fallen in recent years, the level of ground-level ozone pollution in the air is still quite high. Seventeen per cent of the EU urban population lives in areas where the EU ozone target value for protecting human health was exceeded in 2010. More worryingly, more than 95 % of the total EU urban population is exposed to ozone levels above World Health Organization guidelines.

Up to 69 % of agricultural crops in EEA member countries were exposed to ozone levels in excess of the EU target value for protecting vegetation from 2001 to 2009 (EEA core set indicator 005).

Air pollution, including ozone, also has economic costs. A recent study by the EEA found that the air pollution released by the 10 000 biggest industrial facilities in Europe cost up to €169 billion in 2009. This was calculated by adding the cost of poor health, premature death and crop damage caused by ground-level ozone and other pollutants including fine particulate matter.

There are several laws in the EU and internationally which set limits for air pollutant emissions or their concentrations in air.