Concentrating on reducing urban air pollution will have positive effects on health

New research suggests focusing on reducing air pollution in cities will have a beneficial effect on the health of the most disadvantaged communities.

Concentrating on reducing urban air pollution will have positive effects on health
Reducing typically urban sources of pollution from roads, wood burners, and machinery would reduce the health imbalances associated with poor air quality.

Focussing on reducing sources of fine-particle air pollution in urban areas will help meet UK air pollution targets and maximise health benefits for the most disadvantaged communities.

The Imperial College London-led study shows reducing typically urban sources of pollution from roads, wood burners, and machinery would reduce imbalances in how different communities suffer the health impacts of poor air quality.

Fine-particle pollution

Air pollution can cause short-term irritation of the lungs, impact health and lung function in the long term, and exacerbate serious health problems like heart failure and asthma. People living and working in more deprived areas are disproportionately impacted by air pollution.

“People facing higher air pollution in deprived areas suffer health inequalities, which have a profound impact on their quality of life,” explains lead researcher Dr Huw Woodward from the Centre for Environmental Policy. “Reducing air pollution will benefit everyone, but thinking more deeply about how we get there can also help us alleviate the impact on the most vulnerable in society.”

This study focused on PM2.5, a type of fine-particle pollution. The UK Environment Act of 2021 set a target for cutting exposure to PM2.5 by 35% by 2040 compared to 2018 levels, which requires the reduction of pollution from industry, road transport, energy production and agriculture. Cutting pollution from these sources by different proportions can help experts and policymakers meet targets, but most studies have focused on reducing exposure, not how reaching the target would influence health inequality.

New metric

The study considered pollution at a population level as individual exposure is very difficult to estimate. Researchers created a new metric, the Indicator of Exposure Bias (IoEB), to track how different scenarios impact health inequality, and paired it with the UK Integrated Assessment Model used to explore the impact of future emissions scenarios on air quality in England.

They modelled several scenarios, including two that meet the 2040 target, and used the IoEB to assess their impact on the exposure bias. ‘Successful’ scenarios achieved the target by reducing PM2.5 sources from all sectors, but one focused more on urban sources like road transport and wood burners. This scenario had a larger impact, reducing the bias by 59%, compared to 43% for the other scenario.

Concentrating on reducing urban air pollution will have positive effects on health
Emissions from industry also need to be considered, not just those under English control but from neighbouring countries too.

The study also revealed a North-South divide: the south experiences higher levels of PM2.5 pollution, likely due to pollution from shipping channels and neighbouring countries, but also has fewer deprived areas which reduces the overall bias towards deprived areas. Despite this, deprived areas still have higher levels of PM2.5 pollution from all sources, including those outside the UK.

Researchers say the new metric can be applied to different countries or regions using models that estimate population exposure and socio-economic status, which could allow policymakers to identify the sectors which contribute disproportionately to the bias in exposure and effective strategies to reduce bias.

News Reference

Woodward, H., Oxley, T., Holland, M., Mehlig, D., & ApSimon, H. (2024). Assessing PM2.5 exposure bias towards deprived areas in England using a new indicator. Environmental Advances.