Project Firestorm: Assessing Respiratory and Mental Health Impacts of Wildland-Urban Interface Fires and Long-Term Toxic Exposures

SUMMARY / ABSTRACT The Los Angeles firestorms in January 2025 burned over 50,000 acres, destroyed over 16,000 homes and other structures, and displaced over 150,000 Los Angeles County residents. Most importantly, the fires have significantly impacted air quality across the Los Angeles Basin. The fires released high levels of fine particulate matter, VOCs, CO, NOx, and ozone precursors, exacerbating respiratory and cardiovascular conditions for those throughout Los Angeles. These findings stress the need to study long-term health impacts of wildland- urban interface (WUI) wildfire smoke. The acute and longer-term health effects of exposures from these catastrophic wildfires have yet to be defined. A better understanding of WUI) fire-related exposures and the health impacts is an urgent public health priority for Los Angeles. We will collect biological samples from affected individuals and analyze home dust, surface contaminants and outdoor soil and ash over time. After a wildfire it is critical to assess exposure levels and characterize the composition of toxins before home clean-up and environmental factors, such as wind and rain, alter its distribution or concentrations. We propose to conduct Project Firestorm, a rapid study to quantify the health effects of the wildfires. We will leverage an existing cohort of over 9,000 USC faculty, staff, and students who participated in a longitudinal COVID-19 study in 2021-2022. These participants, most of whom live in or around Los Angeles, have completed surveys about their physical and mental health and sociodemographics, providing an essential baseline assessment. The participants have signed consent forms giving their permission to be recontacted for future studies, enabling us to launch the study quickly without extensive recruitment time. We will recontact these participants and invite them to complete a survey about the effects of the fires on physical, mental, and financial health over the next year. From those who complete the survey (N=approximately 3000), we will recruit and collect more detailed data from a sample of 200 participants--100 who lived near the fires (fire-adjacent) and 100 who live over 15 miles away from the burn site (fire-distant). These participants will provide health outcome data on respiratory and other key outcomes, hair samples, wear silicone bracelets for VOC measurements, and samples of their house dust, surface wipes and yard soil for analysis, in February-March 2025 and again in February-March 2026. We will analyze (1) differences between fire-adjacent and fire-distant participants at baseline, and (2) change over a one-year period among fire-affected households and more distant households. Findings will guide public health interventions, long-term remediation efforts, and strategies to mitigate the WUI fires’ health impacts. Project Number: 1R21ES038077-01 | Fiscal Year: 2025 | NIH Institute/Center: National Institute of Environmental Health Sciences (NIEHS) | Principal Investigator: Jennifer Unger (+1 co-PI) | Institution: UNIVERSITY OF SOUTHERN CALIFORNIA, Los Angeles, CA | Award Amount: $456,500 | Activity Code: R21 | Study Section: Special Emphasis Panel[ZES1 LWJ-D (TS)] View on NIH RePORTER: https://reporter.nih.gov/project-details/11272787