Low-income, underrepresented populations at greater risk for chemical exposures

CHICAGO — Low-income and underrepresented populations are at greater risk for neurodevelopmental effects related to chemical exposures, according to an expert at the 2022 American Neurological Association annual meeting.

“Data from the CDC shows that 90% of pregnant women in the United States have detectable levels of neurotoxic chemicals in their bodies, resulting in babies being born already exposed to — and perhaps at increased risk for — disorders of brain development,” Devon Payne-Sturges, DrPH, MPH, MEngr, associate professor at the University of Maryland School of Public Health, said during the presentation.

Payne-Sturges cited seven exemplar chemicals — lead, mercury, organophosphate (OP) pesticides, polybrominated diphenyl ethers (PBDEs), phthalates, polychlorinated biphenyl (PCBs) and air pollution — as chief culprits in health disparities.

When defining health disparities — a particular type of health difference that is closely linked with social, economic and/or environmental disadvantages — Payne-Sturges reviewed each chemical and its subsequent link to these disparities based on race, geography, income, occupation and refugee/immigrant status.

For example, Payne-Sturges said, lead exposures most often were found in low-income Black children, while Black and Hispanic children most often were exposed to high levels of OP pesticides. Higher levels of ambient pollution were found in predominantly non-white and low-income communities, with children from these households more likely to have higher PBDE levels.

According to Payne-Sturges, Hispanic children living in farming communities may experience adverse IQ outcomes because of pesticide exposure, while Black children exposed pesticides are at greater risk for effects on social responsiveness. Children from low-income families exposed to air pollution may be at risk for IQ and cognitive function issues.

Continued and broader research, Payne-Sturges noted, is crucial to expanding the body of knowledge and forming a more complete picture for neurodevelopmental health disparities. In her estimation, that means more effort for study of rural and agricultural areas in lieu of urban environments; more research on underserved populations such as Asian/Pacific Islanders, Native Americans and other indigenous groups; more studies undertaken on adolescents; and longer studies on adverse effects from the teen years into adulthood.

Payne-Sturges also noted the lack of research on mercury, phthalates, PCB and PBDE contaminants, as well as chemical mixture exposures.

“These communities are also exposed to other interrelated conditions that are detrimental to brain health,” Payne-Sturges said. “We’re talking [about] institutional racism and housing and education and employment and poverty. So, we need to focus on the root causes of these detrimental exposures.”