gms | German Medical Science

Background: Particulate matter (PM) with a diameter smaller than 2.5 micrometer in ambient air is the environmental risk factor with the highest attributable burden worldwide. According to the global burden of disease (GBD) study around 4.2 million deaths and about 118 million disability-adjusted life years (DALYs) were attributable to PM2.5 in 2019. In Germany, considerable efforts have been made to reduce PM2.5-emissions, which resulted in a continuous decrease in ambient air pollution concentrations already since 1995. However, this trend reached a plateau in recent years. We estimated the burden of disease attributable to PM2.5-exposure in Germany for the time series from 2010 to 2021.

Methods: We used the environmental burden of disease (EBD) methodology developed by the World Health Organization and estimated the disease-specific population attributable fractions, years of life lost due to death (YLLs), years of life lived with disability (YLDs) and DALYs. For the exposure assessment we combined annual average measured and modelled PM2.5-concentrations with information on population density at a 2-by-2 km² grid. Using the exposure-response functions from the GBD-2019 study we estimated the EBD for chronic obstructive pulmonary diseases (COPD), type 2 diabetes mellitus (T2DM), lung cancer (LC), stroke (S) and ischemic heart diseases (IHD). To estimate the baseline burden of disease, we used the national cause of death statistics for mortality and data from the ‘German Health Update’ as well as the German Centre for Cancer Registry for morbidity assessments. We present average values with 95% confidence intervals (CI).

Results: For all health outcomes combined, we estimated 232,863 (95%-CI: 153,716-314,882) DALYs attributable to PM2.5 in 2021. We observe a reduction of about 50% compared to 2010. The highest attributable burden was estimated for IHD with 70,197 (95%-CI: 42,609-101,785) DALYs, which is about 8% of the overall IHD-burden. The lowest attributable burden was modeled for stroke with 32,740 (95%-CI: 22,734-45,685) DALYs. The mortality-to-morbidity ratio revealed that YLLs had a higher share (69.9%) of overall DALYs with 162,561 (95%-CI: 106,918-222,567) YLLs as compared to the YLDs with 70,302 (95%-CI: 46,798-92,316). The share of YLDs differed strongly in the cause-specific results with only 4% of the DALYs for LC in contrast to 64% for T2DM.

Discussion: Despite a decreasing trend of the EBD for PM2.5 in Germany since 2010, our results show that with 232,863 DALYs in 2021 there is still a long way to a pollutant free environment as envisaged by the EU’s zero pollution ambition for the year 2050. Using EBD as a standardized methodology and the DALYs as the core measure allows to have a comprehensive and comparable overview of the impact of PM2.5 on population health. We selected health outcomes with the highest level of evidence for the causal association between exposure and health effect. However, we assume that our results present an underestimate because we see an increasing evidence for further health outcomes such as neurodegenerative or birth outcomes. EBD-estimates can support tracing trends of risk factor impacts on population health over time and provide additional arguments for policy decision making processes.

The authors declare that they have no competing interests.

The authors declare that an ethics committee vote is not required.