Overview
- Peer‑reviewed findings in Environmental Science & Technology report the first analysis focused specifically on wildfire smoke during pregnancy and autism risk.
- The study examined more than 200,000 Southern California births from 2006 to 2014 using modeled PM2.5 at home addresses to estimate wildfire smoke exposure.
- Third‑trimester exposure showed graded increases in risk, with about 10% higher odds for 1–5 smoky days, 12% for 6–10 days, and 23% for more than 10 days.
- Associations were clearest among mothers who did not move during pregnancy, suggesting sustained local exposure may matter.
- Outside experts flagged small effect sizes, limits of outdoor‑only exposure estimates, and inconsistent dose‑response in some analyses, and they encouraged research on mitigation measures such as air filtration or masks.