Does air quality influence road safety? We estimate the effect of increased air pollution on the number of road traffic accidents in the United Kingdom between 2009 and 2014. To address concerns of spurious correlation we exploit atmospheric temperature inversions as a source of plausibly exogenous variation in daily air pollution levels. We find an increase of 0.3–0.6% in the number of vehicles involved in accidents per day for each additional 1 μg/m3 of PM2.5. The finding suggests that less safe roads may present a large and previously overlooked cost of air pollution. The results are robust to a number of specifications and across various sub-samples.

Lutz Sager, Estimating the effect of air pollution on road safety using atmospheric temperature inversions, Journal of Environmental Economics and Management, Volume 98, 2019, 102250, ISSN 0095-0696,

Keep in touch with the Grantham Research Institute at LSE
Sign up to our newsletters and get the latest analysis, research, commentary and details of upcoming events.