A woman wearing a face mask walks in heavy smog in Harbin, northeast China's Heilongjiang province, on October 21, 2013. Choking clouds of pollution blanketed Harbin, a Chinese city famed for its annual ice festival on October 21, reports said, cutting visibility to 10 metres (33 feet) and underscoring the nation's environmental challenges.   CHINA OUT     AFP PHOTO        (Photo credit should read STR/AFP/Getty Images)
How deadly is air pollution?
01:08 - Source: CNN

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71% of 2,971 cities worldwide exceed WHO guidelines levels for particulate matter

Greater numbers are at risk of heat waves, pollution and mosquito-borne disease

CNN  — 

Climate change is already affecting the health of populations around the world, but things are set to get worse if adequate changes aren’t made, according to an international consortium of climate experts.

Fueling the impact is the fact that more than 2,100 cities globally exceed recommended levels of atmospheric particulate matter – particles emitted when fuels, such as coal or diesel, are burned and are small enough to get into the lungs – says a report published Monday in the medical journal The Lancet.

In the UK alone, 44 cities exceeded levels recommended by the World Health Organization.

Since 1990, exposure to fine particulate matter – smaller than 2.5 micrometers in diameter – increased by 11.2%, the report states, aided by a slow transition away from fossil fuels.

Climate change “is the major health threat of the 21st century,” said Hugh Montgomery, co-chairman of The Lancet Countdown on health and climate change and director of the Institute for Human Health and Performance at University College London in the UK. “There’s an urgent need to address it.”

The latest report highlights multiple health, weather and economic consequences that need immediate attention.

Poor air quality

“Air pollution is one of the leading causes of premature mortality globally,” said Paul Wilkinson, professor of environmental epidemiology at the London School of Hygiene and Tropical Medicine, who co-authored the report.

More than 803,000 deaths across 21 Asian countries in 2015 were attributable to pollution from coal power, transport and the use of fossil fuels at home, the report states.

But there are “some glimmers of hope,” he said, such as the fact that coal power peaked in 2013 and is now showing evidence of a decline.

Investment in coal also declined from 2013, Wilkinson said, but this “will take a couple of generations to realize.”

Wilkinson urges governments to prioritize moving away from fossil fuels, as their harms to the environment and human health have long been known. But 71% of 2,971 cities in the WHO’s air pollution database exceed the organization’s annual exposure guideline for particulate matter.

Increased disease

“Cases of dengue fever have doubled every decade since 1990,” Montgomery said. More people are getting it due to climate change, he said, and “it’s going to go up.”