Emergency Department Visits in California Associated with Wildfire PM2.5: Differing Risk Across Individuals and Communities
Smoke from the North Complex fire settles over San Francisco, turning the daytime sky a dark orange.
By Christopher Michel, via Wikimedia Commons
This study analyzed the impact of wildfire smoke PM2.5 on emergency department visits in California from 2012 to 2019, finding increased risks for all-cause, non-accidental, and respiratory visits but not for cardiovascular visits. The research also revealed that the health risks associated with wildfire smoke exposure varied across subgroups defined by age, race, and air conditioning prevalence, with lower air conditioning availability linked to higher health risk.
This highlights the increasing public health risks associated with wildfire smoke exposure, particularly as wildfire activity intensifies. By identifying the varying impacts on different population subgroups and how these impacts differ based on measures of vulnerability and adaptation, the study provides essential insights for developing targeted interventions and policies to protect vulnerable communities from the adverse health effects of wildfire smoke.
Health impacts from wildfire smoke (WFS) are increasing. A growing literature has documented important adverse health effects of WFS exposure, but how vulnerability to WFS varies across individuals or communities remains poorly understood. We utilized a large database of healthcare utilization claims for emergency department (ED) visits in California across multiple wildfire seasons (May-November, 2012-2019) and quantified the health impacts of fine particulate matter (PM2.5) air pollution attributable to WFS. We aggregated daily counts of ED visits to the level of the Zip Code Tabulation Area (ZCTA) and used a time-stratified case-crossover design and distributed lag non-linear models to estimate the association between WFS and relative risk of ED visits, assessing how this relationship varied by age, race, social vulnerability, and residential air conditioning (AC) prevalence. Over a 7-day period, PM2.5 from WFS was associated with a higher relative risk of ED visits for all causes, non-accidental causes, and respiratory disease, but not cardiovascular diseases. Vulnerability differed by age, race, and AC prevalence, but not social vulnerability index scores, with higher AC availability reducing risk.