Pollution in China Cuts Life Expectancy by 5.5 Years: Study

China’s decades-old policy of providing free coal for winter heating to residents in the north is shortening the lives of people by about 5.5 years and causing higher rates of lung cancer, heart attacks and strokes, according to a new study published on Tuesday.

The study, which appeared in The Proceedings of the National Academy of Sciences, was conducted by researchers from China, Israel and America and was based on analyses of health and pollution data collected by official Chinese sources from 1981 to 2001.

China’s decades-old policy of providing free coal for winter heating to residents in the north is shortening the lives of people by about 5.5 years and causing higher rates of lung cancer, heart attacks and strokes, according to a new study published on Tuesday.

The study, which appeared in The Proceedings of the National Academy of Sciences, was conducted by researchers from China, Israel and America and was based on analyses of health and pollution data collected by official Chinese sources from 1981 to 2001.

According to the study, the practice of providing free coal for fuel boilers to heat homes and offices in cities north of the Huai River, which divides China into north and south, was in effect for much of the 1950-1980 period of central planning. Though discontinued after 1980, it has left a legacy in the north of heavy coal burning, which releases particulate pollutants into the air that can harm human health.

Researchers also found no other government policies that treated China’s north differently from the south.

Studying data for 90 cities, the researchers found that pollution in the north was about 55 percent higher than in the south and life expectancies were about 5.5 years lower on average across all age ranges. The region, which is home to about 500 million people, also had higher rates of deaths due to cardio-respiratory causes such as lung cancer, heart attacks and strokes.

That finding ran counter to predicted life-expectancy based on incomes and demographic factors, they said.

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“The analysis suggests that the Huai River policy, which had the laudable goal of providing indoor heat, had disastrous consequences for health,” the study said. It did not estimate how many lives the policy may have saved from winter cold.

“This was a very well-intentioned policy to provide heat for people in the winter, but we’re uncovering the unintended consequences,” said Michael Greenstone, a professor of environmental economics at the Massachusetts Institute of Technology and one of the four lead authors of the study.

“The legacy of the policy continues today,” he added, noting that many buildings still had the coal-fired boilers that were installed for heating when coal was free, often with few filters.

“It highlights that in developing countries there’s a trade-off in increasing incomes today and protecting public health and environmental quality, and it highlights the fact that the public health costs are larger than we had thought,” Greenstone said.

China’s breakneck economic development during the past three decades has been accompanied by the widespread degradation of air, soil and water. Environmental worries are now a growing source of social unrest and public protest, particularly because of health concerns, and the report’s findings will increase pressure on the Chinese authorities to do more to tackle pollution.

China’s cabinet last month promised measures such as accelerating the installation of pollution control equipment on small, coal-fuelled refineries and curbing emission intensity in key industries by 30 percent by the end of 2017.

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