The ONS (Office for National Statistics) have published* some analysis on a potential link between exposure to air pollution and increased risk of death from COVID-19.
Prof Anna Hansell, Professor in Environmental Epidemiology, Director of the Centre for Environmental Health and Sustainability and Director of the NIHR Health Protection Research Unit in Environmental Exposures and Health at the University of Leicester, said:
“There are a number of preliminary studies suggesting some associations of air pollution with COVID-19, including this one. As the ONS study shows, the relationships between COVID-19, deprivation, ethnicity and air pollution are complex. What is needed now are detailed individual level research studies to explore these further – and this will take time. Scientific opinion on this is reflected in the title of a current editorial in the European Respiratory Journal “Go slow to go fast: A plea for sustained scientific rigor in air pollution research during the COVID-19 pandemic” -see note (1).
“This ONS study uses non-standard methods for air pollution research that provide an initial assessment only. There are two issues in the methods that may have led to the study reporting results smaller than those reported in previous studies. Firstly, the analysis divides the country into areas based on level of deprivation, population density and air pollution. Looking at areas rather than individuals, together with pre-selection on the variable of interest (air pollution) may make it more difficult to detect any true effect. Secondly, the analysis uses air pollution averages for 1kmx1km areas, which is going to lead to errors in estimating the exposures of an individual e.g. if they live on a busy road within that 1km square, again making it more difficult to detect any true effect.
“Air pollution is already known to result in an estimated 40,000 deaths per year in the UK and to increase susceptibility to respiratory infections other than COVID-19. This, and information from a number of studies on air pollution and COVID-19 to date, give extra emphasis to the crucial importance of a green recovery that will help reduce our exposure to air pollution in the future. National and local government initiatives to encourage walking and cycling to reduce journeys made by car are a good start.”
(1) Dick J.J. Heederik, Lidwien A.M. Smit, Roel C.H. Vermeulen. Go slow to go fast: A plea for sustained scientific rigor in air pollution research during the COVID-19 pandemic. European Respiratory Journal Jan 2020, 2001361; DOI: 10.1183/13993003.01361-2020 https://erj.ersjournals.com/content/early/2020/06/18/13993003.01361-2020
Prof Alastair Lewis, Professor of Atmospheric Chemistry, National Centre for Atmospheric Science, University of York, said:
(Prof Alastair Lewis was involved in advising the ONS on study design so is not commenting on the appropriateness of the methodology but is commenting on the conclusions of the work)
“The study shows that some of the early associations made between exposure to air pollution and an increased risk of COVID-19 mortality were artificially enhanced because the disease initially spread in large cities. As COVID-19 became more evenly distributed through the UK over time the effect of air pollution on mortality became less pronounced. The ONS analysis shows that long-term exposure to air pollution does still potentially increase the risk of mortality from COVID-19 but by perhaps less than has been reported in other studies that looked at the effects early in the pandemic.
“The analysis does highlight however the significant disparities that exist in exposure to air pollution in the UK. Geographic areas with a large fraction of their population from ethnic minorities experience considerably higher concentrations of both nitrogen dioxide and PM2.5, on average, compared to regions with a predominantly white population. Ethnic minority communities have been some of the most affected by COVID-19 and it is very plausible that higher exposure to air pollution will be a contributory factor.”
*The analysis ‘Does exposure to air pollution increase the risk of dying from the coronavirus (COVID-19)?’ by the Office for National Statistics was published on 13th August
All our previous output on this subject can be seen at this weblink:
Prof Anna Hansell: is a member of the scientific advisory committee, the Committee on the Medical Effects of Air Pollution (COMEAP), but these comments are made in a personal capacity and do not necessarily reflect the views of COMEAP.
Prof Alastair Lewis: Prof Alastair Lewis was involved in advising the ONS on study design
None others received.