The World Health Organization has released stringent air pollution guidelines in response to the latest information on the damaging affect on health, but experts say none of the world’s 100 biggest cities would meet the updated rules.
In one of the most significant revisions since the standards were established in 1987, the UN agency cut in half the level of fine particulate matter, or PM2.5, deemed acceptable for an individual’s annual average exposure.
Fine particulate matter can travel through the lungs directly into the bloodstream, and is linked to heart disease and stroke.
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