Associations between developmental exposure to environmental contaminants and spatial navigation in late adolescence

Abstract

Inuit communities in Northern Quebec (Canada) are exposed to environmental contaminants, particularly to mercury, lead and polychlorinated biphenyls (PCBs). Previous studies reported adverse associations between these neurotoxicants and memory performance. Here we aimed to determine the associations of pre-and postnatal exposures to mercury, lead and PCB-153 on spatial navigation memory in 212 Inuit adolescents (mean age = 18.5 years) using a computer task which requires learning the location of a hidden platform based on allocentric spatial representation. Contaminant concentrations were measured in cord blood at birth and blood samples at 11 years of age and at time of testing. Multivariate regression models showed that adolescent mercury and prenatal PCB-153 exposures were associated with poorer spatial learning, whereas current exposure to PCB-153 was associated with altered spatial memory retrieval at the probe test trial. These findings suggest that contaminants might be linked to different aspects of spatial navigation processing at different stages.

Introduction to the special issue: Environmental contaminants and child and adolescent development

“…The first article in this issue by Bastien et al. (2022) examined environmental contaminants and spatial navigation among Inuit adolescents living in northern Quebec, Canada. Inuit communities, like many of the populations studied in the articles in this special issue, face disparate risk of exposure to several environmental contaminants.…”