Air pollution falling but more to be done

As pollution in England falls, a new report underlines the lifelong health risks of exposure to polluted air. Rates of outdoor pollution remain high in cities and the south east, while work is now needed to limit indoor emissions.

The annual air pollution report from The Chief Medical Officer for England, released last week, shows that rates of outdoor air pollution have reduced significantly since 1990, with some positive health effects. More must be done, according to Professor Chris Whitty, who recommends reducing emissions from transport, creating more areas that encourage cycling and walking, and reducing indoor pollution to limit the health inequalities caused by pollution

The health of people living in disadvantaged communities is more likely to be affected by pollution than those from affluent areas. Areas with high rates of child poverty are also likely to show higher rates of air pollution, which can affect children’s development and health throughout their lives. Air pollution and climate change are also closely linked: both are driven largely by burning fossil fuels, while hot weather makes smog more likely to form.

Outdoor air pollution is estimated to contribute up to 38,000 deaths a year in England, a figure that is likely to be an underestimation according to Professor Whitty. Air pollution has a negative impact on health throughout life. It is linked to lower birth weight, slower lung development for children, and increased risks of asthma, heart disease, lung cancer, strokes and dementia.

In London, where the most air pollution data is available, roadside emissions of nitrogen dioxide have reduced 44 per cent since 2017, while the second largest form of pollution – particulate matter – dropped by over a quarter. In 2017 London was the first English city to work towards Low and Ultra Low Emission Zone schemes, limiting traffic in neighborhoods.

The health benefits from this drop in nitrogen dioxide is clear. In the latest data from 2019, 174,000 Londoners were living in areas where air quality was over the World Health Organisation’s (WHO) guidelines and UK legal limit for nitrogen dioxide, down from two million in 2016. Professor Whitty makes the link between this drop and the 30 per cent reduction in hospital admissions for asthma and serious lung conditions between 2014 – 2019, with the largest improvement for children under 14 years old.

There are significant inequalities in exposure to air pollution in the capital. Between 2013 and 2019 people living in the most disadvantaged areas of London were 50% more likely to be exposed to nitrogen dioxide when compared with those in the least disadvantaged areas, according to research from the Greater London Authority. The report also found that whilst the gap has reduced neighbourhoods with predominantly white populations are still more likely to have lower levels of pollution than those with predominantly Black or minoritised ethnic populations.

There can be long term benefits from even small decreases in London’s air pollution; the Chief Medical Officer’s modelling estimates that reducing just one unit of particulate matter would prevent over 50,000 cases of heart disease, over 16,000 strokes, over 4,000 cases of lung cancer and over 9,000 cases of adult asthma by 2035. Since the Covid-19 pandemic, other cities with the lowest rates of air quality including Birmingham and Bradford have also brought in measures to reduce air pollution including Clean Air Zones.

If these measures to cut pollution continue to be brought into cities, the report estimates that air pollution across the UK will fall further by 2030. However improvement is still required.

The report also highlights indoor pollution as an area where action must be taken. Factors such as heating sources, cooking methods, care and cleaning products can pollute the air. Safe and comfortable housing is one of the building blocks of health but is not available to everyone; environmental hazards like mould, damp, asbestos, or carbon monoxide are more likely to affect people living on low incomes or in disadvantaged areas. The report concludes that not enough is known about indoor pollution and its health effects, as differences in homes and public buildings vary drastically.