PhilSA: Air quality over Metro Manila unchanged since Navotas landfill fire started

The quality of air in Metro Manila has not returned to normal since the fire started at the Navotas landfill based on data provided by the Philippine Space Agency (PhilSA) as 'smoldering conditions' persist, according to Raffy Tima's report on "State of the Nation."

The PhilSA has conducted daily monitoring of satellite data since the Navotas landfill fire started on April 10, 2026.

"As of Thursday (23 April), the Bureau of Fire Protection has reported “smoldering conditions” onsite and satellite data show that air quality in Metro Manila has not returned to normal levels," said PhilSA.

"Daily monitoring of nitrogen dioxide (NO2) concentration over Metro Manila (taken every 8:45AM), shows that levels are still higher than on 6 April, prior to the fire. Nitrogen dioxide is a pollutant produced from burning and is a component of smoke," PhilSA added.

The map provided by PhilSA shows the estimated smoke extent over Metro Manila and surrounding provinces at 8:45AM on Thursday, 23 April.

"Colors indicate the level of concentration of NO2, with darker red colors indicating higher levels of concentration," the agency added.

PhilSA, however, clarified that observations were limited to 8:45 a.m. for daily comparison, but NO2 levels generally decrease throughout the day.

"This pattern is called a diurnal cycle which may be attributed to atmospheric processes such as easterlies, sea breeze and land breeze, and the dissolution of the inversion layer," the agency said.

"PhilSA’s support through the analysis of satellite data provides wide-area coverage that assists the NDRRMC Health Cluster in monitoring the situation and prioritizing areas for response," the agency added.

Meanwhile, the Air Quality monitoring conducted by the Department of Environment and Natural Resources (DENR) line agency the Environmental Management Bureau (EMB) showed many areas have been classified to have "fair" air quality.

For Valenzuela City, however, air quality monitoring for PM 2.5 recorded the highest reading with 177 Air Quality Index (AQI), classified as "very unhealthy" or 150 - 200 AQI.

PM 2.5 or fine particulate matter that measures about less than 2.5 micrometers pollution is caused by vehicle exhaust (especially diesel), industrial emissions, power plants, wildfires, agricultural burning, and residential heating.

Based on the EMB website, this means pedestrians should avoid heavy traffic areas. People with heart or respiratory disease, such as asthma, should stay indoors and rest as much as possible. Unnecessary trips should be postponed. People should voluntarily restrict the use of vehicles.

Navotas landfill update

Meanwhile, the Department of Health (DOH) has set up a field hospital in Obando, Bulacan to closely monitor the residents' health amid the smog from the burning Navotas landfill.

According to Raffy Tima’s Thursday report on “24 Oras,” several evacuees immediately sought medical attention at a field hospital, including a baby who had to be nebulized due to difficulty breathing.

Residents of Barangays Binuangan and Salambao may be forced to evacuate if the situation worsens, as they are located over a kilometer from the Navotas landfill. — BAP, GMA News