Low emission zones in cities deliver real health benefits - Lancet

Air pollution is a global menace to human health. The World Health Organization (WHO) says 99% of the world’s population lives with air pollution above safe limits. So it’s great news that measures to curb vehicle emissions are steadily improving health in our cities.

WHO says air pollution is associated with 7 million premature deaths each year as a result of heart disease, stroke, chronic obstructive pulmonary and acute respiratory infections. More than 1 in 10 air pollution-related deaths result from respiratory tract cancers.

But now there’s new evidence that restricting polluting vehicles from city centres using clean air low emission zones (LEZs) can produce measurable health benefits. LEZs use charging to discourage highly polluting vehicles from entering built-up areas.

A team from Imperial College, London analysed available health studies conducted in the more than 320 low emission zones across Europe, and concluded that there had been a reduction in the prevalence of all health conditions linked to air pollution in those areas.

Publishing their findings in The Lancet, the team concluded there were “observable health benefits from schemes restricting private vehicles in cities”. As well as reducing pollution-related harms, having fewer cars in cities also cut the number of road deaths, they added.

One of the biggest health gains from the clean air zones was a reduction in heart and circulatory disease accompanied by fewer heart attacks and strokes. Blood pressure problems were also reduced, with the greatest benefits for older people.

“This review shows that LEZs are able to improve health outcomes linked to air pollution, with the evidence being most consistent for cardiovascular disease, such as heart disease and strokes,” Rosemary Chamberlain of the study team told The Guardian.

Although the results of the surveys included in the study varied, none of them showed a deterioration in public health in the clean air zones, the report’s authors noted.

The timing of the Imperial College study is opportune, as London Mayor Sadiq Khan battles opponents to his plan to extend the city’s Ultra Low Emission Zone (ULEZ) from the centre to cover the entire London urban area from the end of August 2023.

Khan chairs C40, a global alliance of city leaders dedicated to cleaning up the air in urban areas. In June 2023, C40 launched Breathe Cities, a $30 million initiative to raise awareness and provide technical help to cities to curb air pollution.

C40 says London’s ULEZ has already benefited 4 million residents, cutting nitrogen dioxide (NO2) emissions in the inner city by a fifth and reducing vehicle CO2 emissions across London by 800,000 tonnes.

More than half of the global population currently live in cities, according to World Bank data, a figure that is forecast to double by 2050. C40 adds that more than two-fifths of cities suffer air pollution that is seven times higher than WHO safety levels.

A study published in June 2023 found that older diesel cars were emitting up to 10 times the permitted level of nitrogen oxide (NOx) when driven in urban areas and called on regulators to enforce higher emissions standards.

The World Economic Forum’s Alliance for Clean Air is “a corporate movement for clean air” in which members set targets to reduce air pollutants and champion change and innovation.