Science and Technology Undersecretary and Philippine Institute of Volcanology and Seismology (Phivolcs) OIC Renato Solidum Jr. said the smog observed in Metro Manila was not due to the Taal Volcano's steady emission of sulfur dioxide that caused volcanic smog or "vog" over the volcano island on Monday, June 28.

"The smog in Metro Manila is simply pollution from vehicle and industrial emissions. The volcanic plume from Taal is blown towards the northeast and not to Metro Manila," Solidum said in a text message to the Manila Bulletin on Tuesday, June 29.

"The haze in Metro Manila is from the ground up and noticeable especially in the morning and along major roads," he further explained.

Phivolcs has warned those living around Taal Lake to take necessary precautions should sulfur dioxide gas emissions continue at the same rate, which has been at 4,330 tonnes per day over the past week.

In the volcano bulletin issued on Tuesday, the volcano's sulfur dioxide emission was measured at an average of 14,326 tonnes per day on Monday, June 28, which is higher than the 4,771 tonnes daily average on Sunday, June 27.

People with asthma, lung disease, and heart disease, as well as elderly, pregnant women, and children, were advised to stay indoors, as much as possible.

"Protect yourself. Cover nose, ideally with an N95 facemask. Drink plenty of water to reduce any throat irritation or constriction," Phivolcs advised.

"If belonging to the particularly sensitive group of people above, watch over yourself and seek help from a doctor or the barangay health unit if needed. If serious effects are experienced, call the doctor or the barangay health unit," it also said.

Solidum reminded the public that Taal Volcano remains under Alert Level 2 due to continuous "increased unrest."

"Magma beneath the volcano is degassing and steam-driven or gas-driven explosion can occur, hence Taal Volcano Island should be avoided," he said.