Manila, Sept. 21 -- The Environmental Management Bureau-Davao Region (EMB-11) said that ambient air monitoring stations across the region reported mixed air quality levels as of 7 a.m. on Monday.

In its bulletin, the Tagum station recorded good conditions while the Malita, Digos, and Calinan stations registered "unhealthy for sensitive groups" due to elevated particulate matter (PM2.5).

PM2.5 refers to microscopic airborne particles measuring 2.5 micrometers or smaller - about 30 times thinner than a human hair. Because of their size, these particles can penetrate deep into the lungs and enter the bloodstream, making them a significant health concern, especially for people with respiratory or cardiovascular conditions.

"Data showed Tag...