PM2.5 exposure biggest global risk factor for death, report says

Exposure to fine particulate matter (PM2.5) is the biggest global risk factor for early death, according to the 2019 Lancet Countdown report.

The annual report, which represents findings and consensus of 35 leading academic institutions and UN agencies from every continent around the world, examines how climate change, urbanisation and economics impact on human health.

It warns that as the planet becomes hotter and our thirst for fossil fuels only slowly decreases, climate change and air pollution will result in millions more early deaths over the next decade.

According to the report, there were 2.9 million premature deaths globally in 2016 that were associated with ambient PM2.5 pollution, a figure which barely improved on 2015.

In Africa, household cooking primarily contributes to high PM2.5 concentrations; whereas in other regions, industry, transport, electricity generation, and agriculture are the primary contributors.

Small decreases in the number of premature deaths have been observed in Europe and the Western Pacific region mainly from the closure of coal power plants.

The report credits sustained improvements over the past 10 years in these regions, such as introducing end-of-pipe emission controls on power plants  and on other emission sectors in Europe

However, worldwide, more than 440,000 premature deaths are still estimated to be associated with coal burning.

A theme of the report is how our societies have become increasingly urbanised over the past few decades, and it predicts that almost 70% of the world’s population will live in cities by 2050 – with many already air pollution hotspots.

The report says that knowledge of the sources of air pollution is ‘essential’ if city designers are to plan effective mitigation measures to tackle the problem.

However, cities in Europe and the USA have seen slowly decreasing PM2.5 concentrations with effective implementation of air pollution control legislation and regulation.

Regarding transport, petrol and diesel fuel use increased by 0·7% from 2015 to 2016 as fossil fuels continue to dominate, but their growth is being tempered by increases in biofuels and electric vehicles (EVs).

Fuels used for transport currently produce more than half of the nitrogen oxide (NOx) emitted globally and a substantial proportion of particulate matter, posing a large threat to human health, the report says, which urges a shift away from cars towards walking and cycling.

This ‘modal shift’ in transport could also result in reductions in air pollution from tyre, brake, and road surface wear, in addition to a reduction in exhaust-related particulates.

Finally, the report criticises national governments for continuing to give massive subsidies to the fossil fuel industry.

In 2018, fossil fuel consumption subsidies increased to US$427bn, over a third higher than in 2017 and more than 50% higher than in 2016.

These subsidies promote overconsumption, further exacerbating both greenhouse-gas emissions and air pollution, according to the report.

Dr Penny Woods, chief executive of the British Lung Foundation, said: ‘This research suggests our children are on course to inherit a world of rising temperatures and filthy air.

‘The UK’s leaders must take action now and set out major changes to clean up our transport system — such as getting polluting vehicles off the road, accessible and affordable public transport, and more funding for cycling and walking infrastructure.

‘Bold, decisive, joined-up action is the only way to protect our planet and our health.’

Photo Credit – Thomas Barrett