B3630 - Prenatal and early-life exposure to heavy metals and childhood neurodevelopment - 09/10/2020

B number: 
Principal applicant name: 
Sarah Lewis | University of Bristol
Kyle Dack, Dr Dheeraj Rai, Caroline Taylor
Title of project: 
Prenatal and early-life exposure to heavy metals and childhood neurodevelopment.
Proposal summary: 

Arsenic, cadmium, lead, and mercury (As, Cd, Pb, Hg), are toxic elements with no known biological functions. Long-term exposure to these elements is possible through the food chain, water contamination, and air pollution depending on local conditions. Arsenic appears to impair neurocognitive performance but not behavioural outcomes (Tolins et al, 2014), and the impacts on language or motor development are less clear. There have been few studies to date of cadmium and neurodevelopment (Rodriguez-Barranco et al, 2013), although previous work within ALSPAC found no association with motor skills (Taylor et al, 2018). Mercury at high-doses is known to delay neurodevelopment (Grandjean & Herz, 2011), but the evidence for an effect at more realistic low-levels is unclear. The strongest evidence of harm during childhood from heavy metals is exposure to lead which has been reliably linked to impaired cognitive, behavioural, and motor development (Sanders et al, 2009). For each of these elements there is a potential to strengthen the evidence base through the use of genetic methods unbiased from confounding factors, and to examine less-studied neurodevelopmental outcomes.

Impact of research: 
May have an important public health impact if strong evidence of an effect for a particular heavy metal. This could result in measures to restrict exposure even further and improve neurodevelopmental outcomes
Date proposal received: 
Tuesday, 6 October, 2020
Date proposal approved: 
Friday, 9 October, 2020
Epidemiology, Developmental disorders - autism, Statistical methods, Genetic epidemiology