Wuhan, capital of Hubei province, suffered the worst air pollution of all monitored sites in China on 12 June, Chutian Metropolis Daily reported. A major cause was said to be straw burning in rural areas surrounding the city.

According to data provided by Wuhan environment protection bureau, the average concentration of PM 2.5 in downtown Wuhan exceeded 500 micrograms per cubic metre at nine monitoring points, with the highest level of 895 micrograms per cubic metre recorded at Donghu High-tech Development Zone.

Ministry of Environment Protection data showed that Wuhan’s air quality was the worst among the 161 monitored cities in China between 5 pm and 8 pm.

According to China Daily, farmers no longer use straw as fuel for cooking and heating and can only dispose of it by burning it on their land.