Air pollution kills 7 million people globally – new WHO report

Air pollution is now  the single biggest environmental health risk, according to a new report from the World Health Organisation (WHO), and kills about 7 million people worldwide every year,.

"We all have to breathe, which makes pollution very hard to avoid," says  Frank Kelly, director of the environmental research group at King's College London, who was not part of the WHO report.

One of the main risks of pollution is that tiny particles can get deep into the lungs, causing irritation. Scientists also suspect air pollution may be to blame for inflammation in the heart, leading to chronic problems or a heart attack.

More than half of the fatalities were  due to fumes from indoor stoves, mainly in Asian households. The WHO report notes that many people are exposed to both indoor and outdoor air pollution. The new estimates are more than double previous figures and based mostly on modeling. The increase is partly due to better information about health effects of pollution and improved detection methods. Last year, the WHO's cancer agency classified air pollution as a carcinogen, linking dirty air to lung and bladder cancer.

Kelly says it is mostly up to governments to curb pollution levels, through measures such as  legislation, moving power stations away from big cities and providing cheap alternatives to indoor wood and coal stoves.

People could also reduce their individual exposure to choking fumes by avoiding traveling at rush hour or by taking smaller roads. Despite the increasing use of face masks in heavily polluted cities such as Beijing and Tokyo, Kelly says there's little evidence that they work.

"The real problem is  wearing masks sends out the message we can live with polluted air," he says. "We need to change our way of life entirely to reduce pollution." Sapa-AP