26 Mar Prenatal Exposure To Air Pollutants May Produce Structural Brain Abnormalities
MedicalResearch.com Interview with:
Dr. Bradley S. Peterson, M.D
Director of the Institute for the Developing Mind
The Saban Research Institute of Children’s Hospital
Los Angeles Children’s Hospital Los Angeles
Medical Research: What is the background for this study?
Dr. Peterson: Neurotoxic PAH (polycyclic aromatic hydrocarbons) are ubiquitous in the environment, in the home and in the workplace. Emissions from motor vehicles, oil and coal burning for home heating or power generation, wildfires and agricultural burning, hazardous waste sites, tobacco smoke and charred foods are all sources of exposure. PAH readily crosses the placenta and affects an unborn child’s brain; earlier animal studies showed that prenatal exposure impaired the development of behavior, learning and memory. Our group previously reported that exposure to airborne PAH during gestation was associated with multiple neurodevelopmental disturbances, including development delay by age 3, reduced verbal IQ at age 5, and symptoms of anxiety and depression at age 7.
Medical Research: What are the main findings?
Dr. Peterson: Together with Virginia Rauh, ScD and Frederica Perera, DrPH, PhD of Columbia University’s Mailman School of Public Health, we conducted a brain imaging study to test the effects on brain structure of PAH exposure during the final trimester of pregnancy. We used magnetic resonance imaging (MRI) to measure the brains of 40 children from a cohort of more than 600 mother-baby pairs from minority communities in New York City. These 40 children were carefully selected to have no other exposures that would affect brain development. Our findings showed that prenatal PAH exposure led to reductions in nearly the entire white matter surface of the brain’s left hemisphere – losses that were associated with slower processing of information during intelligence testing and more severe behavioral problems, including ADHD and aggression. Postnatal PAH exposure – measured at age 5 – was found to contribute to additional disturbances in development of white matter in the dorsal prefrontal region of the brain, a portion of the brain that supports concentration, reasoning, judgment, and problem-solving ability.
Medical Research: What should clinicians and patients take away from your report?
Dr. Peterson: Exposure to PAH from smoke and exhaust during pregnancy and infancy seems to produce a distinct pattern of abnormalities in brain structure that subsequently lead to ADHD-like symptoms and poorer cognitive functioning. Clinicians should educate prospective parents, especially early in pregnancy, about these risks and urge them to avoid, to the extent possible and for the health of their baby, exposure to smoke, exhaust, and other sources of PAH.
Medical Research: What recommendations do you have for future research as a result of this study?
Response: Additional research should focus on identifying the nature of this PAH-related abnormality in white matter. This will include new brain imaging studies in humans and more basic science research using animal models. Those research efforts will help us to identify ways of countering the adverse effects of PAH exposure on the developing brain. In addition, other research should assess how changing policies affect the level of environmental PAH exposure and the prevalence of these PAH-related brain abnormalities, focusing on their associated societal impact, including the economic consequences of reducing these adverse long-term outcomes.
MedicalResearch.com Interview with: Dr. Bradley S. Peterson, M.D (2015). Prenatal Exposure To Air Pollutants May Produce Structural Brain Abnormalities