ศาสตร์เกษตรดินปุ๋ย : ขอบคุณแหล่งข้อมูล : หนังสือพิมพ์ The Nation
THE CAPITAL’S air pollution situation became more severe yesterday, as the quantity of dangerous PM2.5 particles rose to code-red status of above 90 micrograms per cubic metre of air at many locations. If the level remains that high for three consecutive days, drastic measures may be implemented, perhaps including a ban on the use of cars by 2 million civil servants.
Nearly 10 Bangkok areas were at 7.15am yesterday flagged “code red”, which is triggered when particles with diameters sized at or below 2.5 micrometres reach 90 micrograms per cubic metre of air. More than 30 areas were designated “code orange”, which denotes the beginning of negative health effects, a report by the Bangkok Metropolitan Administration (BMA)’s Environment Office’s Air Quality Division said.
The safe limit in Thailand is considered under 50 micrograms of PM2.5 per cubic metre of air, whereas the World Health Organisation pegs it at 25 micrograms.
The red-coded areas include the Thanon Tok intersection in Bang Kho Laem district with the highest level at 101 micrograms; outside Siam University in Phasi Charoen district with 100 micrograms; Mahaisawan intersection in Thon Buri district with 95 micograms; roadside area in Bang Khunthien district with 95 micrograms; roadside area near Bang Phlat District Office with 94 micrograms; and Sanam Luang in Phra Nakhon district with 96 micrograms.The BMA report, available via bangkokairquality.com, provides the capital city’s readings for PM10 and PM2.5 levels over the past 24 hours.
Thai workers spray water into the air along the main road in the city in an attempt to ease the effects of bad pollution in Bangkok, Thailand, 22 January 2019.// EPA-EFE PHOTO
Meanwhile, the Pollution Control Department (PCD) said in its daily update on the PM2.5 situation that 40 areas of greater Bangkok had yesterday morning reported levels of PM2.5 above what is considered safe. Seven roadside locales (each equipped with an air quality-measuring station) were flagged with the code-red status, the PCD said, while attributing the pollution to the lack of rain and absence of strong winds. The PCD has predicted that there may be less pollution today as stronger winds are expected, though the PM2.5 level would remain within “starting to affect health” level.
The related state agencies are so far standing firm following their conclusion at a Monday meeting that “the smog is still not critical enough to declare the capital a pollution-control area, which might affect tourism and the business sector”, as PCD director-general Pralong Damrongthai later told reporters.
The agencies were instead recommending other pollution-tackling measures to the prime minister including increasing mobile units to detect vehicles with black exhaust smoke in the inner city; checking the condition of city buses; and intensifying rain-making operations later this week, Pralong said.
If the PM2.5 rises beyond 90 micrograms per cubic metre of air for three consecutive days, more intense controls on road traffic and construction sites will be imposed, Pralong said.
The measures could include reducing the number of cars on the road, beginning with asking civil servants and state personnel to avoid driving to work.
If more intensive measures failed to curb pollution, the city may be announced as a controlled are under the Public Health Act, Pralong said on Monday.
More drastic measures are available and could be triggered, such as declaring the capital a “pollution-control area” under Article 9 of the Promotion and Conservation of National Environmental Quality Act. However, Pralong said that would be a last resort, as it would yield negative impacts.
Despite the gradual approach being taken, Pralong insisted that people’s health is of the highest priority.
Meanwhile, independent environmental health expert Sonthi Kotchawat said in a recent Facebook post that the government’s gesture on Monday had made him believe that it does not care about people’s health – unlike how governments in developed countries perceived their citizens. He said US and European governments have set an Air Quality Index for Health (AQIH) and implement measures to contain the problem before the situation escalated.
If the AQIH reading reached 7 to 9 (having 54 to 70 micrograms of PM2.5 over 24 hours), public members, especially “sensitive receptor” children and the elderly, are advised to reduce outdoor activity and warned of eye irritation and coughing, said Sonthi. The governments also launch measures to tackle the pollution at the source, he said.
If the AQIH reading stands at 10 or above (more than 70 micrograms of PM2.5) people have to wear masks while outside, all outdoor activities stopped and classes suspended, while the government declares a pollution-control area to allow immediate implementation of strict measures, he said.
Sonthi said it was imperative that the government took action immediately as many areas in greater Bangkok have 70 to 85 micrograms of PM2.5. The authorities should not wait for PM2.5 levels to exceed 90 micrograms for three consecutive days before they implement more drastic measures, he warned.