Air quality in Ireland cannot be taken for granted as stricter standards come into force in future years, even though it complied with all the pollution limits in 2004, according to the Environmental Protection Agency (EPA).
The quality of air in cities "will depend largely on the effectiveness of traffic management measures and on the degree to which we curtail the growth in urban road traffic," EPA programme manager Gerard O'Leary said yesterday.
He was commenting on the agency's latest air-quality report, which found that recorded concentrations of the pollutants of most concern, particulate matter - tiny dust particles known as PM10s - and nitrogen dioxide (NO2) were lower than in 2003.
However, despite these favourable results from 54 monitoring stations, Mr O'Leary said: "Good air quality cannot be taken for granted. The potential remains for urban centres subject to heavy traffic to breach air-quality standards.
"Levels of PM10s and NO2 were found to be highest in urban areas that experience heavy traffic. While levels of these pollutants are currently in compliance, meeting stricter air-quality standards that are expected to apply in future years is not guaranteed."
PM10s arise from burning solid fuels and from road traffic, in particular emissions from diesel engines. Other sources of particulates include dust from roads, soot from combustion sources and natural sources such as windblown sea-salt.
Because they are very small particles, PM10s can penetrate deep into the lungs, as the EPA report explains. Inhalation can increase the risk of respiratory disorders, especially for children and elderly people.
As in previous years, there were more breaches of PM10 limits at city centre locations. Sixteen "exceedances" were recorded at Coleraine Street in Dublin, although this was much lower than the number recorded in 2003, the report says.
Nitrogen oxides (NOx), which include the two pollutants nitric oxide (NO) and nitrogen dioxide (NO2), arise from power generation plants and motor vehicles through high-temperature combustion.
NO2 concentrations in 2004 complied with future (2010) limits proposed by the latest EU directive on air pollution.
Ozone concentrations in 2004 were lower than in 2003, with no "exceedances" at any of the monitoring stations. Levels of lead recorded were typically less than one-tenth of the limit, mainly due to the widespread use of lead-free petrol.
The report, Ambient Air Quality in Ireland 2004, is available at http://www.epa.ie/NewsCentre/ReportsPublications/
