Harmful air pollution levels still much too high

Air pollution remains the largest environmental health risk in Europe. Despite slow improvements, it is still responsible for more than 400,000 premature deaths every year.

Air pollution shortens people’s lifespan and contributes to serious illnesses such as heart disease, respiratory problems and cancer. Between 2014 and 2016, up to 85 per cent of the EU urban population was exposed to levels of fine particulate matter (PM_2.5) exceeding the air quality guidelines established by the World Health Organization (WHO) to protect people’s health. And up to 98 per cent of EU urban citizens were exposed to ozone levels above the WHO’s guideline value (see Table 1).

Table1. Percentage of EU urban population exposed to air pollutant concentrations above EU and WHO reference levels (2014–2016).

A new report from the European Environment Agency (EEA) presents the latest official air quality data reported by more than 2,500 monitoring stations across Europe. It shows that despite slow improvements (see Figure), high concentrations of air pollutants still have significant health impacts, with particulate matter, nitrogen dioxide (NO₂) and ground-level ozone (O₃) causing the greatest harm.

Figure: Percentage of EU urban population exposed to air pollutant concentrations above WHO air quality guidelines (2000–2016)

In the 41 countries considered, 422,000 premature deaths in 2015 were attributed to PM_2.5 exposure, 79,000 to nitrogen dioxide exposure and 17,700 to ozone exposure. In the EU, the numbers of premature deaths attributed to PM_2.5, NO₂ and O₃ exposure were 391,000, 76,000 and 16,400, respectively.

Table 2 shows the best-estimate figures for total mortality due to exposure to each of the three pollutants, for each of the European countries included in the analysis.

Country-by-country data is presented for the estimated number of years of life lost (YLL) and the YLL per 100,000 inhabitants due to exposure to the different pollutants. Regarding the latter, the largest impacts from PM_2.5 are observed in the central and eastern European countries, which is also where the highest concentrations are observed, i.e. Kosovo, Bulgaria, Serbia, Macedonia, Hungary, Poland and Romania.

The largest health impacts attributable to NO₂ exposure, expressed as YLL per 100,000 inhabitants, are found in Italy, Greece, Spain, France and Germany. Regarding ozone, the countries with the highest rates of YLL per 100,000 inhabitants are Kosovo, Montenegro, Hungary, Serbia and Greece.

It should be noted that the impacts estimated for each pollutant may not be added to determine the total impact attributable to exposure to the three pollutants. Because concentrations – especially those of PM_2.5 and NO₂ – are correlated, additions may result in double counting.

A wider historic assessment included in this year’s report shows that annual premature deaths due to PM_2.5 have been cut by about half a million, from around 960,000 in 1990 to around 445,000 in 2015 in the EEA-39 countries, except Turkey. Taking into account the population growth during this 25-year period, it is clear that health risks associated with air pollution have at least halved – an improvement that is largely due to the implementation of air quality policies and the introduction of emission abatement measures at national and local level which have led, for example, to cleaner cars and lower emissions from industry and energy production.

On top of the health impacts, air pollution continues to damage vegetation and ecosystems. Elevated concentrations of ground-level ozone, for example, damage agricultural crops, forests and plants. In 2015, the EU’s long-term objective for the protection of vegetation was exceeded in 79 per cent of the total EU agricultural area, and the critical level for the protection of forests was exceeded in 61 per cent of the total EU forest area.

Excess deposition of sulphur and nitrogen compounds (from emissions of SO₂, NOx, and NH₃) contribute to the acidification of soil, lakes and rivers, causing the loss of biodiversity. In 2014, six per cent of the EU’s ecosystem area was exposed to acidifying depositions exceeding the limits of nature’s tolerance.

Emissions of NH₃ and NOx also disrupt land and water ecosystems by introducing excessive amounts of nutrient nitrogen, causing eutrophication (the over-supply of nutrients), with resulting impacts on biodiversity. In 2015, about 72 per cent of the EU’s ecosystem area was exposed to nitrogen deposition exceeding the critical eutrophication limits.

This year’s report also looks into tropospheric (ground-level) ozone pollution in some more detail. The development and causes of ozone pollution in Europe, and especially in the Mediterranean, are analysed, along with some abatement strategies. Tropospheric ozone is a secondary pollutant formed from precursor pollutants, such as NOx and VOCs, by chemical reactions in the presence of sunlight.

It is stated that the EU’s long-term objectives for ozone cannot be met without additional action worldwide, and reference is made to a recent scientific assessment report, which emphasises that measures targeting methane emission abatement would be beneficial for both climate change mitigation and ozone reduction.

Christer Ågren

The report “Air quality in Europe – 2018 report” (EEA Report No. 12/2018) is available at: www.eea.europa.eu

Table 2. Estimates of premature deaths attributable to exposure to PM2.5, O3 and NO2 in 41 European countries in 2015.