Wildfire smoke is erasing decades of air quality progress for unborn children

Decades of effort to clean the air—starting with the 1970 Clean Air Act and its subsequent updates—have slashed emissions from cars, factories, and refineries by roughly 80 percent. Yet a new study published in Frontiers in Environmental Health reveals that surging wildfire smoke is undoing those gains for a population with little ability to protect itself: developing fetuses.

The reversal of progress#

Research by scientists at the University of Maryland, College Park found that wildfire smoke exposure during pregnancy is systematically reversing the prenatal health benefits achieved through decades of industrial emission controls. Rather than continuing to improve, air quality outcomes for pregnant people are deteriorating as wildfire activity intensifies.

The problem stems from a feedback loop: unchecked fossil fuel combustion is warming the planet and drying landscapes, conditions that fuel larger and more destructive wildfires. The smoke they produce contains toxic compounds and particulates that are demonstrably more harmful to human health than pollution from traditional industrial and vehicular sources.

Disproportionate impacts on vulnerable populations#

The burden falls heaviest on those least able to escape it. Low-income communities, rural areas, and Indigenous populations experience the most severe consequences of wildfire smoke pollution during pregnancy.

As senior author Michel Boudreaux, an associate professor of health policy and management, explained, the study specifically examined "infants that were born and what their exposure was like during the prenatal period"—a vulnerable window in development when smoke exposure has outsized effects.

Long-term health consequences#

Prenatal exposure to wildfire smoke meaningfully raises the risk that babies will arrive too early or too small, disorders linked to elevated odds of early death and chronic respiratory disease and other conditions throughout life.