Urban population exposure to air pollution in Europe over the last decades

Abstract

Background: The paper presents an overview of air quality in the 27 member countries of the European Union (EU) and the United Kingdom (previous EU-28), from 2000 to 2017. We reviewed the progress made towards meeting the air quality standards established by the EU Ambient Air Quality Directives (European Council Directive 2008/50/EC) and the World Health Organization (WHO) Air Quality Guidelines by estimating the trends (Mann-Kendal test) in national emissions of main air pollutants, urban population exposure to air pollution, and in mortality related to exposure to ambient fine particles (PM_2.5) and tropospheric ozone (O₃).

Results: Despite significant reductions of emissions (e.g., sulfur oxides: ~ 80%, nitrogen oxides: ~ 46%, non-methane volatile organic compounds: ~ 44%, particulate matters with a diameter lower than 2.5 µm and 10 µm: ~ 30%), the EU-28 urban population was exposed to PM_2.5 and O₃ levels widely exceeding the WHO limit values for the protection of human health. Between 2000 and 2017, the annual PM_2.5-related number of deaths decreased (- 4.85 per 10⁶ inhabitants) in line with a reduction of PM_2.5 levels observed at urban air quality monitoring stations. The rising O₃ levels became a major public health issue in the EU-28 cities where the annual O₃-related number of premature deaths increased (+ 0.55 deaths per 10⁶ inhabitants).

Conclusions: To achieve the objectives of the Ambient Air Quality Directives and mitigate air pollution impacts, actions need to be urgently taken at all governance levels. In this context, greening and re-naturing cities and the implementation of fresh air corridors can help meet air quality standards, but also answer to social needs, as recently highlighted by the COVID-19 lockdowns.

Keywords: Air pollution; EU-28; Mann–kendall test; Population exposure; Risk assessment; Trend.

Fig. 1

Annual trends of national emissions (% year⁻¹) in the 28 European Union countries (EU-28) for sulfur oxides (SO_x), nitrogen oxides (NO_x), non-methane volatile organic compounds (NMVOCs), ammonia (NH₃), carbon monoxide (CO), particulate matter with an aerodynamic diameter lower than 2.5 µm and 10 µm (PM_2.5 and PM₁₀) over the time period 2000–2017 (see Additional file 1: Table S1 for raw data). All trends are significant at p < 0.05 (Mann–Kendall)

Fig. 2

Minimum and maximum percentage of EU-28 population (in %) exposed to air pollutants concentrations (particulate matter PM_2.5 and PM₁₀, nitrogen dioxides NO₂ and tropospheric ozone O₃) exceeding the European Union limit or target values between 2000 and 2017 (see Additional file 1: Table S2; data source: [–32]

Fig. 3

Annual trends of mortality (number of deaths per 1,000,000 inhabitants per year) due to ambient particulate matter with an aerodynamic diameter lower than 2.5 µm (PM_2.5) and tropospheric ozone (O₃) over the time period 2000–2017 in the 28 European Union countries (EU-28). Points below the thick line show a decrease in O₃- and PM_2.5-related mortality, while points above the thick line show an increase (see Additional file 1: Table S3 for raw data)