Abstract

Exposure to environmental contaminants is ubiquitous. Studies increasingly suggest that these chemicals pose a risk for human health, including neurodevelopment in children. Prenatal exposure to environmental contaminants warrants particular concern given the fragility of fetal development and the foundational nature of this period for the rest of the lifespan. However, little is known about potential mechanisms. Furthermore, researchers and practitioners in psychology and child development are generally unaware of such toxicological research.
The objective of the present thesis is to examine the impact of prenatal contaminant exposure on neurodevelopment in children, explore avenues for future research on potential mechanisms, improve dissemination of toxicology studies to psychology researchers and practitioners, and advocate for a larger role of psychologists in prevention, intervention, and public policies. To do so, the thesis contains three manuscripts.
The first manuscript is a PRISMA-guided scoping review of studies on prenatal exposure to a wide range of environmental contaminants and various neurodevelopmental outcomes in children. This chapter provides an overview of neurotoxicology research from birth to age 17 inclusively and aims to make these findings more accessible to clinicians and researchers in fields relevant for child development.
The second manuscript is an empirical study within a pan-Canadian pregnancy cohort examining the association between prenatal exposure to a flame-retardant chemical and IQ at age 3 years. This chapter provides a typical example of a developmental neurotoxicology study in terms of its method, results, and effect sizes.
The third manuscript is an empirical study with an American community cohort composed of participants aged 6 to 20 years old. Participants underwent executive function testing and structural brain imaging at baseline and up to two follow-up sessions scheduled 15 months apart. This chapter aims to inform the design of future research into the mechanisms of neurotoxicity following contaminant exposure.
Overall, prenatal contaminant exposure is associated with small adverse effects on cognition for individuals, but has significant societal implications. Future studies should aim to better characterize potential mechanisms like cortical morphology to inform prevention and intervention efforts. Lastly, the thesis highlights the benefits of disseminating neurotoxicology findings to psychologists and child development experts.