Study Unveils Molecular Links between Air Pollution and Negative Birth Outcomes

A new study by Emory University researchers, published in Environmental Science & Technology, found that exposure to the tiny particles in air pollution during pregnancy can disrupt maternal metabolism, altering key biological pathways. These changes were associated with increased risk of various negative birth outcomes, including premature birth.

The study analyzed blood samples provided by 330 pregnant women from the Atlanta metropolitan area.

Key Findings of the study are:

• The study uncovered the specific pathways and molecules involved in energy and amino acid metabolism that may explain how exposure to PM2.5 contributes to preterm and early term births.
• The researchers identified two substances -- cortexolone and lysoPE(20:3) -- as factors in the relationship between short-term air pollution exposure and elevated risk of early births, offering a potential mechanism through which air pollution triggers premature labor.
• The study highlighted disruptions in protein digestion and absorption -- which are vital to fetal development and immune function -- as potential links between air pollution and early births, also offering new potential targets for prevention efforts.
• Of the 330 women who participated in the Emory study, 66 (20%) delivered preterm babies and 54 (16.4%) delivered early term babies, both of which are significantly higher than the prevalence in the general U.S. population.

"As an air pollution scientist, I do not think air pollution is going away anytime soon. Even at lower levels, we continue to see harmful health effects, but we can't just ask people to simply move away from highly polluted areas," says Donghai Liang, PhD, study lead author and associate professor of environmental health at the Rollins School of Public Health. "So, from a clinical intervention standpoint, that's why it's critical to gain a better understanding on these pathways and molecules affected by pollution. In the future, we may be able to target some of these molecules to develop effective strategies or clinical interventions that could help reduce these adverse health effects."

Reference: Zhenjiang Li, Anne L. Dunlop, Jeremy A. Sarnat, Anke Hüls, Stephanie M. Eick, Audrey Gaskins, Howard Chang, Armistead Russell, Youran Tan, Haoran Cheng, Dana Boyd Barr, Alicia K. Smith, Carmen Marsit, Dean P. Jones, Donghai Liang. Unraveling the Molecular Links between Fine Particulate Matter Exposure and Early Birth Risks in African American Mothers: A Metabolomics Study in the Atlanta African American Maternal-Child Cohort. Environmental Science & Technology, 2025; DOI: 10.1021/acs.est.5c02071