PM2.5 level observations during New Year Celebration inIloilo City, Philippines using low-cost sensors

Exposure to high levels of particulate matter (PM) could result to adverse health effects.
The use of fireworks during the New Year celebration result to the rapid increase in
ground-level air pollution which could linger for a few hours or longer depending on the
prevailing meteorological conditions. The rapid increase in the air pollution levels caused
by this event could affect vulnerable groups with underlying health conditions. This
research explores the variations of air pollution levels in select residential areas in Iloilo
City, Philippines during the 2025 New Year celebration. The sensors used are
AirGradient outdoor monitors managed by the Urban Air Quality Monitoring Group at
Central Philippine University. The observation period spanned from December 10, 2024
and January 10, 2025 and is focused on PM2.5 levels to give insight on the overall air
pollution condition. The data shows a total increase in pollution levels throughout all the
stations during the event followed by the subsequent reduction in air pollution levels
hours after the event. The observed PM2.5 concentration ranged from below 35 μg/m 3
prior to the event and up to greater than 500 μg/m 3 in some stations immediately after the
event. At the highest peak, some stations register values more than 40 times greater than
the WHO guideline value for 24-hr exposure. The research offers valuable information
on the air pollution levels in Iloilo City particularly during the New Year celebration. The
use of a network of low-cost sensors gives valuable insight on the characteristic
variations and trends on the air pollution in low-income urban communities and cities in
the Philippines and beyond.