Air pollution kills 1.8 million people and gives nearly 2 million kids asthma each year

By Mark Waghorn via SWNS

Air pollution is killing 1.8 million people across the world each year, according to new research.

It's also causing nearly two million cases of asthma in children, say scientists.

The shock figures revealed in two separate studies highlight the need to reduce exposure - particularly among the young and the elderly.

In the first, researchers looked at PM2.5s - the leading environmental risk factor for disease.

Less than a 50th the width of a human hair, they get into the blood through the lungs making it more sticky - triggering inflammation.

The tiny particles come from diesel fumes, wood smoke, brake pads, tyres and road dust.

Inhalation increases the risk of premature death from cardiovascular disease, respiratory disease, lung cancer and lower respiratory infection.

Lead author Veronica Southerland, a PhD candidate at George Washington University in the US, said: "The majority of the world's urban population still live in areas with unhealthy levels of PM2.5.

"Avoiding the large public health burden caused by air pollution will require strategies that not only reduce emissions but also improve overall public health to reduce vulnerability."

Computer models showed 86 percent of those living in cities worldwide - or 2. 5 billion people - are exposed to annual average levels exceeding World Health Organisation (WHO) guidelines.

The global study is the biggest of its kind - analysing PM2.5s and associated mortality trends in over 13,000 cities over two decades.

Average population-weighted concentrations across all urban areas was 35 micrograms per cubic metre in 2019 - with no change from 2000.

This is equivalent to seven times the 2021 WHO guideline of five micrograms per cubic metre.

The researchers estimate that 61 in every 100,000 deaths in urban areas was attributable to PM2.5 in 2019.

South-East Asia - including India - saw the largest regional increases with a 27 percent rise over the period.

In the second study, researchers looked at NO2 (nitrogen dioxide gas) emitted by vehicles, powerplants, industrial manufacturing and agriculture.

Global concentrations were calculated by combining satellite data with datasets on different types of land use, like roads and green space.

The study is the first to estimate the burden of paediatric asthma cases caused by this pollutant in more than 13,000 cities from Los Angeles to Mumbai.

In 2019 there were 1.85 million new paediatric asthma cases associated with NO2 - 8.5 percent of all those reported that year.

Co-lead author Dr Susan Anenberg, also from George Washington University, said: "Our study found that nitrogen dioxide puts children at risk of developing asthma and the problem is especially acute in urban areas.

"The findings suggest that clean air must be a critical part of strategies aimed at keeping children healthy.

"Our results demonstrate the important influence of combustion-related air pollution on children’s health in cities globally

"In places that have effective air quality management programs, NO2 concentrations have been trending downward for decades, with benefits for children’s respiratory health.

"Even with these improvements, current NO2 levels contribute substantially to paediatric asthma incidence, highlighting that mitigating air pollution should be a critical element of children’s public health strategies."

In 2013, PM2.5s were classed as a carcinogen by the International Agency for Research on Cancer.

The particles were recently implicated in increasing the risk of Covid. The studies are in The Lancet Planetary Health.