Environmental factors and child cognitive development

Source	Environmental factors and child cognitive development: a scoping review of exposome research trends G. Ristovska, K. Persson Waye (in preparation)
Level of evidence	Scoping review Longitudinal preschool in-depth study with children aged between 5-7
Approach	Literature review of 33 papers published between 2000 and 2022 on the exposome and cognitive effects in children. All studies focused on prenatal exposure to environmental factors, studied biomarkers in cord or child blood, and social relationships to assess their combined impact on cognitive development. The in-depth study focused on cognitive abilities before and after the first year of formal education in Germany and Belgium.
Findings	Prenatal and early life exposure to harmful substances: Prenatal and early life exposure to harmful substances, such as tobacco, air pollutants, chemicals, metals combined with social factors and aspects of the internal exposome (e.g., birth weight, duration of breastfeeding, preterm birth, biomarkers, genetic variations) was associated with cognitive impairments during the early and middle childhood. Positive environments: Supportive environments for better cognitive outcomes included green spaces, stable home environment, neighbourhood quality, and quality of learning resources, caregiver responsiveness, kindergartens and school environments. Noise : Sound levels outside the home were not clearly correlated to cognitive outcomes at the age of 6 years. Hearing ability and its functional brain markers correlated with sound at home. This indicates there is a complex multifactorial relationship between noise and cognitive outcomes.
Recommendations	Prenatal exposure to harmful substances should remain a focus of policy paired with a strong parental education component. Implement multisectoral strategies that improve socioeconomic conditions and reduce harmful environmental exposures—including pollutants, toxins, and adverse social factors. Promote nurturing environments across home, educational, and recreational settings, while supporting maternal mental health, to ensure a holistic and equitable approach to early childhood development.