Toxic dust blankets North

A rainmaking plane is deployed to relieve dense smog above the northern provinces of Chiang Mai, Chiang Rai and Lamphun on Sunday. (Photo supplied)
A rainmaking plane is deployed to relieve dense smog above the northern provinces of Chiang Mai, Chiang Rai and Lamphun on Sunday. (Photo supplied)

Northern provinces, especially Chiang Mai and Chiang Rai, were blanketed by unsafe levels of the carcinogenic PM2.5 on Sunday, according to the Health Department.

Dr Suwannachai Wattanayingcharoenchai, director-general of the department, said the levels of PM2.5 exceeded 91 microgrammes per cubic metre of air (μg/m³) in 24 hours in eight northern provinces – Chiang Mai, Chiang Rai, Lamphun, Lampang, Mae Hong Son, Nan, Phayao and Phrae.

Toxic dust was also afflicting the three northeastern provinces of Bung Kan, Nakhon Phanom and Nong Khai as of late Sunday morning, he said.

The safe threshold for PM2.5 in Thailand is set at 50 μg/m³ in 24 hours.

The PM2.5 level in Mae Sai district in Chiang Rai reached 480 μg/m³ on Sunday, Dr Suwannachai said.

The level exceeded the local safe threshold by nine times – and the World Health Organization's (WHO) standard by 32 times, he said.

At 10.30am IQAir, the air pollution monitoring website, reported Chiang Mai was the city with the worst air pollution in the world. The level of PM2.5 in the northern province was 33.4 times as much as the safe threshold set by the WHO.

Dr Suwannachai expected the air pollution to continue in the North and the Northeast, especially on border provinces, this week because of field burning in Thailand and neighbouring countries, along with stagnant air.

The high levels of PM2.5 would cause eye and skin irritation, breathing difficulties and chest pain, he said. Long-term effects include cancer.

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  • afflict: to suffer from a serious problem or illness - กระทบ
  • blanket (verb): to cover something completely - ปกคลุม
  • cancer: a serious disease in which growths of cells, also called cancers, form in the body and kill normal body cells. The disease often causes death - มะเร็ง
  • dust: very small pieces of dirt that cover surfaces inside buildings like a powder - ฝุ่น
  • effect: a change that somebody/something causes in somebody/something else; a result - ผลกระทบ
  • exceed: to go beyond an official limit; to be greater than a number or amount - เกินปริมาณ
  • haze: water, smoke or dust in the air that makes it difficult to see clearly - หมอกควัน
  • irritation: a painful feeling in a part of the body, often with red skin or swelling - การทำให้ระคายเคือง,การยั่วโทสะ,การกวนประสาท,การทำให้ฉุนเฉียว,ความระคายเคือง,การอักเสบ
  • pollution (noun): contaminated, when something has been made dirty, poisonous, unpleasant to see or smell and possibly dangerous to health - การทำให้เป็นมลพิษ, การทำให้สกปรก, ภาวะมลพิษ, สภาวะมลพิษ, มลภาวะเป็นพิษ, สภาพเป็นพิษ, ความสกปรก
  • stagnant: (of water or air) not moving and therefore smells unpleasant - นิ่ง, น้ำทรง
  • threshold: the level or point at which you start to experience something, or at which something starts to happen - จุดเริ่มของประสบการณ์หรือเหตุการณ์ใหม่ๆ
  • toxic: poisonous and harmful to people, animals or the environment - เป็นพิษ
  • μg/m³: microgrammes per cubic metre, a measure used for air pollution -
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