QUANTIFICATION OF METAL CONCENTRATIONS IN PARTICULATE MATTER COMING FROM TRANSIENT AIR POLLUTION IN SOUTHERN CALIFORNIA: FIREWORKS AND WILDFIRES

Particulate matter exposure, both long-term and short-term, has been linked to an increased risk of negative health effects on humans. Exposure to particulate matter with a diameter of less than 2.5 micrometers (PM_2.5), is especially dangerous, as particles can penetrate deep into the lungs and bloodstream. The composition of particulate matter is what makes it toxic to humans. There are consistent sources of particulate matter, such as vehicular emissions and there are transient sources, like fireworks and wildfires. Both consistent and transient sources are known to emit heavy metals in particulate matter. Heavy metals in the ambient air are known to be extremely toxic and some carcinogenic. Metal pollutants like lead, chromium and arsenic are heavy metals emitted into ambient air are extremely dangerous for human exposure. This study investigates the effects of transient sources of particulate matter air quality, specifically examining firework activity, during July 4^th, 2024, and wildfires during January 2025. The firework activity was monitored in three different sites in Southern California. This study focuses on quantifying the concentrations of metals in PM_2.5. Air samplers with a PM_2.5 inlet (Access Sensors Technology, UPAS v2+) were used to collect particulate matter onto 37 mm mixed cellulose ester (MCE) filters. Filters were then extracted in nitric acid and metals were quantified using inductively coupled plasma-optical emission spectroscopy (ICP-OES, Agilent 5800). Results showed elevated concentrations for strontium and barium along with other metals during firework activity. During wildfire activity, increased concentrations in lead and chromium were observed in addition to other metals.