BY GLENDA TAYONA
ILOILO City – The ambient air quality in this southern city and nearby Oton, Iloilo town remains “good”, according to Environmental Management Bureau (EMB) Region 6 director Atty. Ramar Niel B. Pascua, citing their four stations monitoring Particulate Matter (PM) and Total Suspended Particulates (TSP) in the air.
These are still within the National Ambient Air Quality Guideline Values, said Pascua.
Ambient air quality monitoring is an important step for taking corrective actions to reduce air pollution and let the public know of the quality of the air they breathe, he explained.
PM is a mixture of solid particles and liquid droplets in the air while TSP refers to all atmospheric particles with diameters equal to or less than 100 micrometers. These relatively “coarse” particles are mainly related to soiling and dust nuisance.
EMB’s monitoring stations are in La Paz district plaza, University of San Agustin, the public plaza of Leganes, Iloilo and Oton Central Elementary School – all within what the bureau refers to as the “Metro Iloilo Airshed”.
Sampling is done every six days for a 24-hour exposure period, said Pascua.
Data from La Paz Ambient Air Quality Monitoring Station showed the air quality index from April 6 to June 29 to be all “good” – ranging from 16 to 29 mass per unit volume (expressed as µg/NCM) or within the standard value which is 230 µg /NCM.
The recorded concentrations for the year 2019 (pre-pandemic) here were higher compared to the results for the years 2020, 2021 and 2022, according to Pascua.
In March 2019, the La Paz station logged the highest value with over 250 µg/NCM.
Pascua attributed the drop in particulate concentration to limited human activities and the lessening of motor vehicles moving around due to coronavirus pandemic-induced slowdown of economic activities.
The regional director cited three major sources of air pollutants: mobile, area and stationary.
Mobile sources are motor vehicles moving on land, sea and air.
Area sources of air pollutants include emissions through processes such as the production of methane by decaying organic materials, grass fires, building construction, dry cleaning, unpaved roads, dumpsites/landfills, and the small scale burning combustible materials, like charcoal from households and commercial food preparations.
On the other hand, air pollutants emitted by facilities with geographically-fixed locations and Air Pollution Source Installation (APSI) like standby generator sets and boilers are referred to as stationary sources of air pollutants./PN
