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The study's methodology is fundamentally flawed because it relies on modeled exposure levels based on residential addresses without accounting for critical individual factors such as time spent indoors, access to air filtration systems, or outdoor activity patterns. Exposure levels can vary dramatically within just 10 miles, making these broad geographic estimates unreliable for drawing meaningful conclusions about individual risk. The identified correlation doesn't establish causation, and without controlling for confounding variables and accounting for missing data points, these findings are too weak to support definitive claims.
Air pollution during pregnancy poses severe documented risks to fetal development, as harmful pollutants cross the placenta, directly interfere with critical growth stages and trigger maternal inflammation and oxidative stress. Research demonstrates strong associations between prenatal exposure to specific PM2.5 components — particularly sulfate and ammonium — and increased autism risk, while the second and third trimesters show especially vulnerable windows. These pollutants disrupt normal fetal brain development and raise risks for premature birth, low birth weight and long-term neurological consequences.