New research reveals stark disparities in where harmful air pollutants are emitted across England, with important implications for future air quality policies. 

Minoritised ethnic groups, often living in urban centres or near major roads, face disproportionately high levels of harmful emissions of air pollutants – discovered by an air quality research team at the National Centre for Atmospheric Science and University of York. 

While at a national level air pollution continues to reduce, poor air quality is still the greatest environmental risk to human health. But exposure to air pollution is not uniform – it is influenced by weather, geography, economic development, regulations, and local to regional emissions sources such as transport, energy, and industry.

The likelihood of experiencing poor air quality has been linked with socioeconomic status for some time. We know that the most deprived areas in England experience the highest levels of air pollution emissions, mainly due to people living, working, or studying close to major roads, close to industry and in areas of high housing density.

This new study, published in Environment International, separates the effects of deprivation from ethnicity as factors that influence people’s proximity to sources of harmful air pollution. We asked Nathan Gray, a doctoral researcher at the University of York, to explain their approach and what the results were:

“By combining data from the 2021 census on socioeconomic deprivation and detailed information on population ethnicity at fine scales with air pollution emissions data in England, we identified that all 24 minoritised ethnic groups studied experienced higher than average air pollution emissions than socio-economically matched populations in the majority ‘White: English, Welsh, Scottish, Northern Irish or British‘ ethnic group. What this means is that minoritised ethnic groups in England, regardless of their level of deprivation, face disproportionately high levels of harmful air pollution emissions – namely nitrogen oxides and particulate matter, also known as NO_x and PM_2.5.” 

Living near to road transport and in city centres are well-known reasons for ethnicity and deprivation-based differences in exposure to air pollution. NCAS air quality scientists also explain that air pollution from industry, homes, and construction create issues of the same magnitude – seeing disparities in proximity to sources of nitrogen oxides and particulate matter also in suburban settings, smaller towns and some rural areas.

Nathan Gray sets out the main findings of the study, relating to nitrogen oxide gas:

“Chinese, Arab and Bangladeshi communities experienced the largest disparity in emissions of nitrogen oxide, 100%, 91%, 89% higher than majority white populations of matched deprivation status. For nitrogen oxides, the largest contributors leading to disparity were road transport, followed by domestic combustion, and then industrial sources.” 

And for particulate matter:

“Bangladeshi, Pakistani and Roma groups experienced on average 40%, 40%, 36% higher particulate matter emissions than socio-economically matched white groups. For particulate matter, the greatest contribution to disparity actually comes from domestic combustion, then road transport and industry,” says Nathan Gray. 

This research underscores a pressing issue, where socio-economic and ethnic inequalities intersect with environmental hazards and people’s health. Dr Sarah Moller, senior research fellow at the National Centre for Atmospheric Science and University of York, explains:

“The inequalities in the distribution of emissions are particularly significant for nitrogen oxides and particulate matter. People who are part of minoritised ethnicity groups, who are also experiencing the highest levels of deprivation, often live closest to major roads and in areas of high housing density. Densely populated areas expose residents to pollutants created by combustion from heating.”

“Our research clearly reveals environmental injustice. People in minoritised ethnic groups across England experience higher emissions of air pollution – from all major sources – regardless of levels of deprivation. This includes minoritised white ethnic groups experiencing higher emissions than the majority white,” says Professor Alastair Lewis at the National Centre for Atmospheric Science and University of York.

Across England, it is now clear that inequalities in air pollution are widely experienced. The research team suggests that specific emissions reduction strategies will be important in determining future equity in emissions, and that policies should focus on a range of emissions sources – road, domestic, and industry.

The UK’s air pollution in the coming few decades will be different to the recent or distant past – and it will change as energy supplies and transport systems are decarbonised, lifestyles and working practices evolve, and as new materials, products and processes are adopted.

Dr Sarah Moller shares grounds for hope: “We believe that better understanding of air pollution emissions across England, fuelled by studies like ours, will have important implications for future UK government policies aimed at reducing air pollution that go hand-in-hand with tackling inequalities.”

Photo credit: Mary Turner