The Interior Ministry has ordered provincial authorities to immediately start preventive measures against PM2.5 now the country has entered the high-pollution risk season.

An expert has urged the government to lower the safe limit from 50 to 25 microgrammes per cubic metre (µg/m³) as recommended by the World Health Organization (WHO).

Interior Minister Anutin Charnvirakul had ordered provincial governors and Disaster Prevention and Mitigation offices across the country to impose PM2.5 pollution prevention measures.

The high-pollution risk season lasts during winter, especially in 17 northern provinces, Bangkok and nearby cities.

Provincial authorities are required to reach out to locals and promote alternative waste management to avoid open burning which can lead to wildfires, the government said.

Mr Anutin also ordered punishments for those who break the law.

A lecturer at Chulalongkorn University said areas with the highest number of lung cancer deaths are in the northern region and Bangkok where air pollution is often the worst in the country.