Changes in ambient particulate matter exposure and evaluation of its health relevance in Germany

INTRODUCTION: To evaluate the health relevance of fine particulate matter (PM2.5), it is necessary to assess the PM2.5 exposure of the populations. For this purpose, time series (2010-2021) for two PM2.5 indicators for Germany were developed: (1) the mean population-weighted PM2.5 exposure per year and (2) the proportion of the population exceeding the recent WHO air quality guideline value for PM2.5 of 5 µg/m(3) (annual mean). METHODS: To calculate the two indicators for the period 2010-2021, nationwide modelled annual means of PM2.5 background concentrations were used. They were joined with spatial information on population density from the 2011 census. The population data were additionally scaled for each year according to the official population update. On this basis, the population could be assigned to different PM2.5 exposure classes per year. RESULTS: Over the years considered, the mean population-weighted PM2.5 exposure in Germany decreased by approximately 41 %: in 2021, the indicator value of 9.3 µg/m(3) was significantly lower than in 2010 with 15.9 µg/m(3). However, throughout the time series, almost 100 % of the German population was exposed to PM2.5 annual mean concentrations above the current WHO air quality guideline value. CONCLUSIONS: Generally, the decreasing PM2.5 exposure of the German population is very positive. Measures taken in recent years to reduce emissions from stationary sources and the transport sector have contributed significantly to this development. On the other hand, the large proportion of the population above the WHO guideline value shows that the current annual average PM2.5 reduction is still far from being sufficient to protect human health. In fact, far-reaching measures are required to significantly reduce particulate matter concentrations in Germany. KEY MESSAGES: • The mean population-weighted particulate matter exposure in Germany has decreased significantly in recent years. • The exposure reduction in Germany is still not sufficient. To protect human health, further and far-reaching measures are required to significantly reduce particulate matter concentrations in Germany.