Wildfire smoke offsets US prenatal air quality gains

A study published in Frontiers Media analyzed 64.5 million pregnancies across 2,842 counties in 48 US states from 2003 to 2019. It found that while overall prenatal PM2.5 exposure declined by about 34%, wildfire smoke's contribution more than doubled from 3.7% to 8.2%. By 2019, wildfire smoke accounted for about 65% of days with unhealthy air quality for pregnant women. The study highlights that wildfire smoke is offsetting gains from reduced anthropogenic pollution, disproportionately affecting low-income, rural, and Indigenous communities. Lead author Menglu Liang of the University of Maryland, College Park emphasized the need for targeted public health interventions. The study period predates recent severe wildfire seasons in the US and Canada, suggesting the trend may have worsened.