New research links air pollution to severe Covid-19 progression. This should prompt a re-evaluation of German commitments to safeguarding and improving air quality. Clean air deserves a more prominent place in Germany’s Strategy for Sustainable Development 2020.
In Germany, air pollution is a topic that only occasionally makes headlines. Prior to Covid-19, the most recent burst of media attention came when a retired physician went on TV and declared that he had never seen a patient die from air pollution, and that there was no scientific basis for the air quality limit values in place to protect public health in Germany and the EU. Although this claim was swiftly rebutted by myriad members of the medical and scientific community, the reaction of Germany’s transport minister was to suggest that the EU limit values were too strict and required re-evaluation. And although Germany has laws and programs in place to promote clean air, safeguarding and improving air quality is not high on the government’s agenda. The weak response to the diesel emissions scandal and the half-hearted attempts to deal with NO2 limit value exceedances are further cases in point.
Air pollution a key factor in Covid-19 deaths?
With the arrival of the Covid-19 pandemic, air pollution has suddenly become newsworthy again, not only because lockdowns around the world have reduced emissions, leading to temporarily cleaner skies, but also because regions with severe air pollution have seen higher rates of Covid-19 mortality. Prominent examples of this are Wuhan in central China and the Po Valley in northern Italy, a hotspot for air pollution in Europe. In a preprint of the most comprehensive study of the links between air pollution and Covid-19 mortality to date, scientists from the Harvard T.H. Chan School of Public Health found that an increase in fine particulate matter (PM2.5) by only 1 µg/m³ is associated with an 8% increase in the death rate due to Covid-19, including in relatively unpolluted regions. To put this in perspective, the EU limit value is 25 µg/m³ as an annual average. The World Health Organization (WHO) recommends even lower levels of pollution to protect health: not more than 10 µg/m³ of PM2.5 as an annual average, and not more than 25 µg/m³ as a 24-hour average  to protect against the negative effects of short-term exposures. The German Environment Agency reports that in 2019 the WHO guideline for annual average PM2.5 was exceeded at more than half of Germany’s monitoring stations and the short-term exposure guideline was exceeded at nearly all (98%) of them. Clearly, there is much room for improvement: reducing PM2.5 pollution in Germany to the levels designated safe by the WHO would lower the incidence of cardiovascular and lung disease, thereby improving baseline health and increasing societal resilience in the face of the next pandemic.
IASS is examining the role of air pollution in this pandemic
Scientific work on the links between exposure to air pollution and the severity of Covid-19 progression is still in its infancy, so we should be careful not to read too much into initial results. Nonetheless, there is nothing surprising about the finding that poor prognoses in cases of SARS-Covid-19 are linked to air pollution exposure. It is well established that long-term exposure to PM2.5 is a risk factor for cardiovascular and lung disease, and it has already been shown that PM2.5 exposure is associated with increased risk of severe outcomes in the case of other infectious respiratory diseases, including influenza, pneumonia, and SARS.
The IASS is contributing to research examining the impact of air pollution on human health in the context of this pandemic and more broadly as part of a collaboration with Charité Universitätsmedizin Berlin. In addition, the IASS is approaching the Covid-related emissions reductions as a chance to learn from a real-life experiment, using data gathered under these exceptional circumstances to help evaluate and improve the urban-scale models that are often used to support policy decisions.
Clean air requires political will
The emerging evidence that air pollution increases the likelihood of severe Covid-19 progression, combined with a renewed public awareness of the harmful effects of air pollution, should be taken as an opportunity to review whether German commitments to safeguarding and improving the quality of our air are commensurate with its true value. Deaths due to Covid-19 will always be more personal and directly relatable than the more diffuse threat of air pollution. Yet it is worth reminding ourselves that epidemiological studies show that outdoor air pollution contributes to more than 4 million premature deaths worldwide every year. Indeed, a recent study from the Max Planck Institute for Chemistry estimated that air pollution leads to excess mortality  of 790,000 each year in Europe; 154,000 of those excess mortalities are in Germany. The same study estimated that air pollution reduces average life expectancy in Europe by 2.2 years (in Germany by 2.4 years).
Clean air is essential for a healthy society and deserves a more prominent place in the German Sustainability Strategy, where it has important linkages to thematic focus areas of mobility and climate. More specifically, the Strategy should do more to support a mobility transition that actively moves Germany away from its car-centric focus, which would provide cleaner air and contribute to climate change mitigation. At a European level Germany should push for adoption of the WHO air quality guidelines as the EU limit values. This would represent a significant increase in ambition on clean air and could also be designed to achieve significant co-benefits for climate.
Science, policy and society should re-envision a liveable future together
Within the scientific community, work at the intersection of health, air quality and climate should be strengthened with a focus on interdependencies and synergies. For example, improving the representation of emissions and their sources at local scales would enhance the capacity of models to provide useful outcomes for scientific understanding and policymaking. Inter- and transdisciplinarity should be integral to scientific work in this area, with value placed on engaging the public in a discussion on new and creative concepts for re-envisioning the spaces where we live and work, our related mobility needs and preferences, and how these choices connect to our physical and mental health. Indeed, the importance of engagement with civil society and a well-functioning science-policy system has only been underscored during the Covid-19 crisis. The development of the required communication competencies (sometimes referred to as “outreach” or “transfer” activities) among scientists also deserves more attention and support, not just in times of crisis
 Not to be exceeded more than three days per year.
 The number of deaths that occurred under the observed polluted conditions, over and above what would have been expected under clean conditions.
This perspective was submitted to the Online-Konsultation: Nachhaltig aus der Corona-Krise von der Wissenschaftsplattform Nachhaltigkeit 2030.