By Arabella Balderama

On Friday, September 22, 2023, heavy haze hovered over the different parts of Metro Manila while vog caused by Taal blanketed the municipality of Batangas.

Smog is a gray cloud formed by atmospheric pollutants from vehicle emissions, while vog is the sulfur oxide-laden dust coming from Taal Volcano.

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) announced that the smog experienced in Metro Manila “is not related” to the volcanic activities of Taal.

“The vog was over areas on the western side of Taal Volcano,” PHIVOLCS said, adding that the vog was detected to be drifting west-southwest of the volcano, which is not the direction going towards Metro Manila.

A representative from the Department of Environment and Natural Resources (DENR) supported PHIVOLCS, claiming that based on the direction of the air, the smog experienced in Metro Manila was not due to the Taal Volcano.

Meanwhile, Department of Science and Technology Secretary Renato Solidum stated that the smog was caused by “thermal inversion,” while the vog was from volcanic gas.

Both weather disruptions prompted local governments to suspend classes, specifically in areas near Taal, as well as those in Metro Manila.

Unhealthy air quality

According to DENR’s air quality monitoring data, several Metro Manila regions are now experiencing poor air quality, particularly in the cities of Parañaque, Pateros, and Makati.

“The smog may be primarily attributed to emissions from heavy vehicular traffic, especially during rush hour. Air quality varies in time and places and can change anytime depending on pollution sources and meteorological factors,” the agency explained.

The air quality in Pateros and Makati is currently categorized as “unhealthy for sensitive groups,” urging the DENR to caution those with respiratory ailments to limit their outdoor exposure.

Parañaque residents received the same warnings as the municipality has “acutely unhealthy air quality.” Individuals with heart or respiratory diseases were encouraged to stay indoors as much as possible.

On the other hand, PHIVOLCS Director Teresito Bacolcol cautioned that exposure to vog in Taal may result in irritation of the eyes, throat, and respiratory tract.

Thumbnail from The Manila Times