A senior World Health Organization official has suggested that Chinese governments shoulder more responsibility in helping poor people combat the negative effects of smog.

Air purifiers that help to clean dangerous particulate matter during badly polluted days should be accessible to more people, Bernhard Schwartlander, the WHO China Representative, said in an interview with China Daily.

At present, many air purifiers cost hundreds or thousands of dollars each and contain filters that are also costly to replace. Even face masks, which help to reduce the amount of particulate matters that the wearer breathes in, cost at least 20 yuan ($2.9) and last for no more than a week in heavy smog.

Those on a reasonable income may be able to afford such costs, Schwartlander said, but governments should look into how the poor can get equal protection.

He suggested the government subsidize the purchase of air filters for impoverished households.

Previous WHO estimates have said that 3 million people die globally every year from outdoor air pollution, many of them in China.

The Chinese government has launched nationwide investigations to study the long term health affects of air pollution.