Introducción del documento publicado por la Agencia Europea de Medio Ambiente:
This report analyses and presents changes in air pollutant emissions and their possible health or ecosystem impacts in Europe covering the period 1990–2004.
Emissions of all air pollutants fell substantially during the period 1990–2004 in the 32 EEA member countries (EEA-32), resulting in improved air quality over the region. However, ambient concentrations of particulate matter and ozone in the air have not shown any improvement since 1997, despite the decrease in emissions. This might be due to meteorological variability and growing long‑distance transport of pollutants.
Fine particulate matter with a diameter size below 2.5 micrometer (PM2.5) is now generally recognised to be the main threat to human health from air pollution. As sulphur emissions have fallen, ammonia emitted from agricultural activity and nitrogen oxides from combustion processes have become the predominant acidifying and eutrophying agents affecting ecosystems.