A visible haze blankets Quezon City on September 1, 2026, as smoke from wildfires in Kalimantan, Indonesia, drifted across parts of Luzon and contributed to deteriorating air quality in Metro Manila, according to the DENR-Environmental Management Bureau (EMB). Maria Tan, ABS-CBN News
MANILA – Air quality in Metro Manila has started to improve after several areas recorded “very unhealthy” levels in recent days, with the Department of Environment and Natural Resources (DENR) saying the conditions were caused by a combination of transboundary haze from Indonesia and local pollution sources.
As of 6 a.m. Friday, October 2, two cities had stations that recorded “unhealthy” air quality, while the rest of the 18 monitoring stations in the National Capital Region registered “fair” or “good” readings, according to Jundi Del Socorro, chief of the Environmental Quality Management Division of the DENR-Environmental Management Bureau (EMB).
“Bumuti-buti na po ngayon. Ngunit as of 6 a.m. ngayong umaga sa ating 18 air quality monitoring stations,” Del Socorro said in an interview on DZMM.
“Dalawang siyudad may naitalang unhealthy po ngayon sa tatlong station. Ito ay Las Pinas at Parañaque. At the rest naman ay fair at good naman ang kalidad ng hangin,” Del Socorro added.
The air quality began deteriorating on Sept. 29, with the highest levels recorded on Sept. 30, before slightly declining on Oct. 1 and continuing to improve.
“Bumuti na po kasi nagsimula ‘yan noong September 29. 30 ang pinaka mataas talaga ang level. Medyo bahagyang bumaba ng October 1 at ngayon unti-unting bumubuti na po,” he said.
On Sept. 30, several Metro Manila areas recorded “very unhealthy” PM2.5 levels, with Las Piñas, Parañaque, Muntinlupa, Caloocan and Taguig among those affected.
The EMB attributed the deterioration partly to thermal inversion, which traps pollutants near the ground.
‘VERY UNHEALTHY’ AIR
The Philippines uses six air quality classifications: good, fair, unhealthy for sensitive groups, very unhealthy, acutely unhealthy and emergency.
For “very unhealthy” air quality, authorities advise people to reduce exposure to pollution, particularly those with respiratory or cardiovascular conditions.
“Pag very unhealthy po, talagang nire-recommend natin na i-postpone ang mga lakad na ito, lalong-lalo kung meron tayong mga comorbidities at irestrict na rin ang paglapit sa mga sources ng pollution tulad ng mga usok at emission galing sa sasakyan,” Del Socorro said.
He said PM2.5 is particularly concerning because of its extremely small size.
“At ito lalong-lalo nasa PM2.5 kung saan ito ay tinong-tinong alikabok kung saan maaaring sumama sa ating bloodstream at magbigay ng hindi mabuting epekto sa kalusugan ng ating mamamayan,” he said.
Del Socorro said exposure to elevated PM2.5 may worsen existing respiratory and cardiovascular conditions.
“So aspirant po, maaari siyang maapektuhan ‘yung kanyang sakit tulad ng mga asthma, cardiovascular diseases at lahat ng mga respiratory diseases po,” he said.
The situation had been more severe in some areas earlier in September. Del Socorro said two monitoring stations recorded “acutely unhealthy” air quality on Sept. 13, a level above “very unhealthy.”
“Noong September 13, meron tayong naitala na dalawang acutely unhealthy na istasyon. Ngunit the rest naman nung sumunod na mga araw, ito bumalik na rin naman sa very unhealthy hanggang sa unhealthy na lang po na level,” he said.
Under the DENR’s air quality classifications, “acutely unhealthy” means pollution levels are already high enough to pose a serious health risk, while “emergency” is the highest classification.
Indonesia haze chokes neighbors, but little legal recourse
How haze from Indonesian fires impacts Southeast Asia
The Philippines has been experiencing haze linked to fires in Kalimantan, Indonesia, with prevailing winds carrying smoke and particulate matter toward parts of the country. The haze has previously affected Metro Manila, Central Luzon, CALABARZON and MIMAROPA.
INDONESIA FIRE NOT SOLE REASON OF POOR AIR QUALITY
But Del Socorro stressed that the recent poor air quality in Metro Manila cannot be attributed solely to the fires in Indonesia.
He identified three major categories of local pollution sources: stationary sources such as industries, mobile sources such as vehicles, and other sources including burning and the resuspension of dust from unpaved roads.
“Dito sa ating bansa may mga local sources din tayo tulad ng meron tayong tatlong major categories, stationary sources galing sa mga industriya, mobile sources o transport galing sa mga sasakyan at sa mga aerial sources. Ito ‘yung mga nonpoint sources tulad ng mga pagsisiga, pag-uusok, ‘yung mga resuspension ng mga unpaved roads,” he said.
According to Del Socorro, the country’s latest emissions inventory shows that transportation contributes to increased pollution levels.
Air quality can also vary depending on wind direction, temperature, atmospheric pressure, traffic and the surrounding built environment.
The DENR has previously said the haze from Indonesia may be transported to the Philippines by prevailing winds.
Del Socorro said changes in meteorological conditions also contributed to the deterioration in air quality, particularly the thermal inversion observed around Sept. 30 to Oct. 1.
Thermal inversion occurs when warmer air settles above cooler air near the surface, effectively trapping pollutants and preventing them from dispersing upward.
The EMB had cited the phenomenon as a possible factor behind the elevated pollution readings in Metro Manila on Sept. 30.
AIR QUALITY ADVISORIES
The DENR official urged the public to continue monitoring air quality advisories, particularly because pollution levels can differ from one area to another and change throughout the day.
For people who need to go outside during periods of poor air quality, Del Socorro said the Department of Health recommends an N95 mask.
For motorists, Del Socorro also recommended using the air-conditioning system’s recirculation mode to reduce the intake of polluted outdoor air.
Despite the recent deterioration, Del Socorro said current conditions indicate a trend toward improvement as wind direction changes and the transboundary haze disperses.
“Nakikita naman natin ngayon baka medyo bumubuti na ang ating lagay dahil nagbabago ang direksyon ng hangin na epekto ng transboundary haze,” he said.
He said the DENR has not observed other major pollution sources in Metro Manila beyond usual urban sources such as traffic.
Metro Manila air quality reaches ‘acutely unhealthy’ levels amid haze from Indonesia