Characterizing metals in particulate pollution in communities at the fenceline of heavy industry: combining mobile monitoring and size-resolved filter measurements

Exposures to metals from industrial emissions can pose significant health risks, particularly in socio-economically disadvantaged communities near heavy industry. This study focuses on the Chester-Trainer-Marcus Hook region in Pennsylvania, where existing environmental monitoring has relied on low-resolution data and self-reported industry data. During a three-week sampling campaign in September 2021, we combined size-resolved filter measurements and mobile monitoring to assess particulate matter (PM) metal concentrations. Our results revealed that fixed-site measurements of arsenic, lead, antimony, cobalt, and manganese were significantly higher than EPA model estimates, with the majority of toxic metals found in fine PM (<2.5mm). Hazard index analysis indicated minimal risk from the observed levels; however, it highlighted the necessity of considering other chemical exposures and non-chemical stressors in future risk assessments. Correlations between stationary and mobile sampling showed moderately strong relationships for aluminum, potassium, and selenium. Source apportionment identified four primary emission sources, with notable elevated levels of combustion-related metals near industrial sites. These findings suggest that current EPA modeling underestimated metal exposure risks in surrounding communities, necessitating more comprehensive monitoring approaches.