European Environment Agency report on ground-level ozone during summer 2012 finds that most member states are exceeding limits
Nearly all EU member states failed to keep levels of ozone within targets set to protect human health during summer 2012, according to a report by the European Environment Agency (EEA).
Estonia was the only EU state to fall within long term objective (LTO) targets for ozone at all its stations. The findings mean other states are likely to miss newer targets that have been phased in recently, the EEA said.
The UK exceeded the LTO at 37 of its 83 stations (45%), although there were only exceedances monitored on 14 days during the period covered, which means it still falls within the EU target value. The maximum observed eight-hour mean concentration of ozone in the UK was 165 micrograms per cubic metre.
The LTO for ozone set by the EU to protect human health is a maximum eight hour mean concentration of 120 micrograms per cubic metre, while the target value states that this should not be exceeded by a member state on more than 25 days each year.
The report found that the 25-day threshold was exceeded in 17 EU members states as well as five other non-EU states that submitted data to the EEA. Also, levels were exceeded at least once at approximately 85% of all operational monitoring stations. The UK did not exceed this threshold.
However, the ground-level ozone report on also found that the number of exceedances of the ‘alert threshold’ was lower than in any year since monitoring of the pollutant began in 1997, which indicates that peak episodes were shorter and maximum ozone concentrations were lower overall.
The alert threshold is a one-hour average ozone concentration of 240 micrograms per cubic metre, which was exceeded on a record low of 25 occasions in seven EU member states — Belgium, France, Germany, Greece, Italy, Spain and Portugal.
As with findings in past studies, the most widespread concentrations of ozone occurred in the Mediterranean area, which the EEA said was because the pollutant is particularly likely to reach unhealthy levels on hot, sunny says.
The lowest number of exceedances is often in northern Europe, according to the report, and there were no exceedances of the information threshold in 2012 except for one in Denmark.
The report states: “Summer 2012 was characterised by short regional ozone episodes with few exceedances of thresholds between mid-June and the end of August. There were only three longer episodes this summer: a six-day episode in June, a five day episode in August and a five-day episode in July.”
According to the report, the largest ozone episode in terms of area affected occurred between 24 and 28 July 2012.
Ground-level ozone levels depend on weather conditions such as sunshine and temperature, and are a result of chemical reactions between other pollutants in the air. These substances are emitted by industry, traffic, farming practices and from other sources.
According to the EEA, ozone pollution can travel great distances, meaning that it is both a local air quality issue and also a global, cross-border problem.
Ground-level ozone can lead to shortness of breath, coughing, scratchy throat, and can inflame and damage airways. It can also aggravate asthma, emphysema, chronic bronchitis and make the lungs more susceptible to infection, according to the US Environmental Protection Agency.
The annual report, ‘Air pollution by ozone across Europe during summer 2012’, is based on data from 2,107 monitoring sites across Europe and covers the period from April to September last year. It was published on the EEA website yesterday (January 31).