In a recent study published within the Environment International Journal, researchers explored the impact of air pollution exposure while pregnant on the neonatal brain.

Study: Prenatal exposure to air pollution is related to structural changes within the neonatal brain. Image Credit: VanderWolfImages/Shutterstock.com

Background

Air pollution exposure is linked to negative effects on cognitive function and brain health. Childhood exposure to numerous pollutants has been linked to developmental delay.

Maternal exposure while pregnant can negatively affect brain development, potentially resulting in cognitive dysfunction. Animal studies have produced inconsistent findings regarding the link between air pollution exposure in the course of the prenatal stages and brain development in youth.

Concerning the study

In the current study, researchers investigated the correlation between in-utero air pollution exposure and neonatal brain development.

The neonatal developing human connectome project (dHCP) included infants born between the gestation age of 23 and 44 weeks, whose age was estimated using the mother’s most up-to-date menstrual period and verified, if possible, via early ultrasound scanning.

The study included neonatal scans of subjects born between 2015 and 2020. The study cohort included 782 infants within the dHCP project, with 469 infants in the ultimate sample. A web-based tool was used to calculate the Index of Multiple Deprivation (IMD) for all infants based on their postcode at birth.

The London Air Pollution Toolkit was used to model maternal exposure to air pollution. The Air Pollution Toolkit employed a technique that combined modeling and measurement and a kernel modeling technique to depict pollution dispersion.

The tool models traffic emissions by considering hourly traffic speeds and flows on different road links. It used a selected vehicle stock for London and data from the National Atmospheric Emissions Inventory (NAEI). The London Atmospheric Emissions Inventory (LAEI) provided emission sources aside from road transport.

Results

The study included 469 infants born with a median gestational age of 40.14 weeks and underwent imaging at 41.29 weeks postmenstrual age.

The study group had a median IMD of 4. The female and male infants were scanned at a median age of 41.43 and 41.07 weeks, respectively. Each nitrogen dioxide (NO2) and particulate matter 10 (PM10) were found to have non-normal distributions. Moreover, the distribution of relative cerebellum and total brain volume (TBV) was not normal.

The study found that higher levels of PM10 and lower levels of NO2 were linked to larger ventricular sizes, moderately linked to larger relative cerebellum sizes, and modestly linked to smaller cortical gray matter (cGM), amygdala, and hippocampus sizes.

Moreover, these aspects were related to a bigger brainstem together with extracerebral cerebrospinal fluid (CSF) in the primary mode. No significant association was found between exposure to PM10 and brain volume measures.

After applying false discovery rate correction, all brain region correlations with the primary mode displayed significance, except the deep gray nuclei and the white matter.

Conclusion

The study findings revealed that prenatal air pollution exposure impacted the scale of the cerebellum and ventricles within the neonatal brain.

During fetal development, the brain is especially at risk of negative effects, which may have long-lasting impacts on a person’s well-being. The study highlighted the importance of reducing exposure to pollution while pregnant, as it will probably adversely affect the newborn’s health.

This finding adds to the present evidence and emphasizes the necessity for public health measures to cut back particulate matter concentrations. Further study is required to interpret the finding that larger relative cerebellar and ventricular sizes are related to lower NO2 exposure.