In a recent interview with Francheska M. Merced-Nieves, PhD, an assistant professor at Mount Sinai and the Institute for Exposomic Research, the associations between a metal mixture and negative infant effects were discussed. Non-essential metals, which have no biological function in the body, can have toxic effects on cellular and molecular mechanisms, especially on brain development and behavior. In contrast, essential metals, such as manganese, play a positive role in our body and are necessary for healthy brain development.
Exposure to heavy metals can occur through inhalation, thermal exposure, or ingestion. Lead, for example, is a commonly known heavy metal that is predominantly ingested. Although lead has been phased out from many products, older buildings and pipes still contribute to exposure. These heavy metals can also be added to various products. The health effects associated with heavy metal exposure in children range from fetal growth issues to lung and brain development problems.
Dr. Merced-Nieves and her colleagues conducted a study focusing on the associations between heavy metal exposure and behavioral effects in infants. They looked at seven non-essential metals, including arsenic, barium, cadmium, chromium, cesium, lead, and antimony. Additionally, they examined the influence of social stressors, specifically cortisol, the stress hormone, to understand the biological embedding of chronic stress experienced during pregnancy.
The study found that increased exposure to both heavy metals and stress was associated with a greater impact on brain development and behavioral issues, particularly fear and sadness. Girls seemed to be more strongly affected than boys, and these behavioral domains have been linked to later psychopathology such as anxiety. However, it is important to note that these factors are not deterministic, and early intervention can help put these children on a healthier track to prevent lifelong psychological problems.
In terms of recommendations for pregnant individuals, Dr. Merced-Nieves emphasized the need for clinicians to provide counseling on better nutrition, which protects brain development and counteracts the toxicity of stress and heavy metals. Stress reduction strategies, along with a high-quality social environment, are crucial for both prenatal and postnatal periods. Providing parents with parenting strategies that foster resiliency can greatly contribute to a child’s healthy development.
Contemporary Pediatrics® interview with Francheska M. Merced-Nieves, PhD, assistant professor at Mount Sinai and the Institute for Exposomic Research and the Department of Pediatrics.