Air Pollutant Improvement – A side effect of COVID-19 preventative measures

Simon Ashman

Simon Ashman
Consultant, Assurity Consulting
3rd April 2020

Satellite images from NASA, showing drastic declines in nitrogen dioxide levels in China have circulated online since late February 2020. Nitrogen dioxide is a pollutant gas produced by industrial processes and vehicle fumes. These results observed in China are attributed to a reduction in general manufacturing and industrial activity amid the COVID-19 containment efforts, in comparison to 2019 statistics. However, has the same trend been observed in the United Kingdom?

Newly published information from the National Centre for Atmospheric Science (NCAS) compared air pollution levels for 2020 to the average levels from the last five years. This data compared nitrogen dioxide and respirable particulate matter (PM2.5) levels in ten major UK cities: Birmingham, Belfast, Bristol, Cardiff, Glasgow, Leeds, London, Manchester, Newcastle and York. Increased respiratory symptoms, aggravation of asthma, irritation of mucous membranes and bacterial infections are just some of the problems related to such pollution levels.

The statistics from the NCAS show a general trend of reduced nitrogen dioxide and particulate matter levels for late February to late March 2020, compared to the average levels between 2015 – 2019. Eight out of the ten UK cities returned lower levels of nitrogen dioxide, with the exceptions of Belfast and York. All ten UK cities returned lower particulate matter levels, below the average levels observed in the previous five years.

These results could be attributed to the significant changes to working and everyday life, amid the COVID-19 pandemic. The government message issued on the 23rd of March 2020 advised the population to stay indoors and limit all but ‘essential travel’. However, many companies across the UK had promoted working from home prior to this. The stricter measures to prevent the spread of the virus in the UK may be having the side-effect of falling pollution levels across UK cities.

The Director of Science at the National Centre for Atmospheric Science, Prof. Ally Lewis, commented, "In the midst of a respiratory health crisis such as this, better air quality can only have a small effect, but it will undoubtedly be positive, relative to business-as-usual levels of pollution. It is further motivation, as if it were needed, to stay inside and not travel unless necessary, since the emissions and pollution avoided makes a helpful difference."