Abstract
Daily exposure to air pollution has been shown to increase cardiovascular and respiratory mortality. While increases in short-term exposure to air pollutants at any daily concentrations has been shown to be associated to adverse health outcomes, days with extreme levels, also known as air pollution peaks based on specific thresholds, have been used to implement air quality alerts in various cities across the globe. We aimed at evaluating the potential effects of the Air Quality Alerts (AQA) system on different causes of premature mortality in Paris, France. Air quality alerts (AQA) based on particulate matter (PM10) levels and related interventions were implemented in the region of Paris in 2008 and were revised to be more stringent in 2011. In this study, we applied a difference-in-differences (DID) approach coupled with propensity-score matching (PSM) to daily mortality data for the period 2000 to 2015 to evaluate the effects of the Paris AQA program on different causes of premature mortality for the entire population and for adults>75years old. Overall, results did not show evidence of a reduction in mortality of the PM10 AQA program when first implemented in 2008 with initial thresholds (80µg/m3); DID estimates were slightly above 1 for cardiovascular and respiratory mortality. However, when evaluating the drastic reduction in revised thresholds in 2011 (50µg/m3) to trigger interventions, we identified a reduction in cardiovascular (DID=0.84, 95% CI: 0.755 to 0.930) mortality, but no change in respiratory mortality was detected (DID=0.97, 95% CI: 0.796, 1.191). Our study suggests that AQA may not have health benefits for the population when thresholds are set at high daily PM10 levels. Given that such policies are implemented in many other metropolitan areas across the globe, evaluating the effectiveness of AQA is important to provide public authorities and researchers a rationale for defining specific thresholds and extending the scope of these policies to lower air pollution levels.
Highlights
In the last two decades, there has been growing evidence of adverse health outcomes being associated with exposure to air pollution which has led to the implementation of air quality standards in various coun tries
While it has been shown that increases at any level of daily exposure to air pollutants are associated with adverse health outcomes including car diovascular or respiratory mortality (Daniels et al, 2000; Dominici et al, 2002; Papadogeorgou et al, 2019; Schwartz et al, 2002, 2001; Schwartz and Zanobetti, 2000; Yan et al, 2019), an emphasis has been made on days with extreme levels of air pollutants, known as air pollution peaks
As no health benefits were observed in the first implementation of the air quality alert system, our study suggested that these types of policies may not have the envisioned health benefits if the selected thresholds are too elevated, in a context of a relatively low levels of air pollution
Summary
In the last two decades, there has been growing evidence of adverse health outcomes being associated with exposure to air pollution which has led to the implementation of air quality standards in various coun tries. In order to prevent adverse health events associated with air pollu tion peaks, air quality alerts (AQA) have been implemented in various metropolitan cities worldwide Such AQA typically involve a large range of measures focused primarily on reducing emissions on days where air pollution concentrations exceed a given threshold. While increases in short-term exposure to air pollutants at any daily concentrations has been shown to be associated to adverse health outcomes, days with extreme levels, known as air pollution peaks based on specific thresholds, have been used to implement air quality alerts in various cities across the globe. Given that such policies are implemented in many other metropolitan areas across the globe, evaluating the effectiveness of AQA is important to provide public authorities and researchers a rationale for defining specific thresholds and extending the scope of these policies to lower air pollution levels
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
