Patna,(BiharTimes): After Delhi, Patna has the highest level of the airborne particulate matter, PM2.5 considered most harmful to health.

With 153 micrograms Delhi is at the top while Patna with 149 micrograms is the second. 

According to a WHO report these figures are six times what it considers a ‘safe’ limit––which is 25 micrograms.

The pollution data released by the World Health Organization (WHO) said half of the top 20 cities in the world with the highest levels of PM2.5 are in India. Other cities with high levels were located in Pakistan and Bangladesh.

PM2.5 refers to the diameter measured in microns of particulates such as ammonia, carbon, nitrates and sulfate -- which are small enough to pass into the bloodstream and cause diseases such as emphysema and cancer.

The WHO data, according to the report, echoes an earlier study this year, which found that air pollution in New Delhi is now worse than Beijing.

No Chinese cities ranked in the top 20 most polluted cities, despite thick, gray smog filling its cities and millions of residents commuting behind surgical masks. Beijing reported 56 micrograms of PM2.5. 

This year, Chinese leaders have declared “war on pollution.”