Battle of wills or perfect harmony? Early exposure to environmental toxicants and parent-child and sibling relationships.

Rationale
Lead exposure in children is a worldwide problem and has a large impact on population IQ loss. Even low blood lead concentrations (BLLs) are associated with a range of cognitive deficits and behavioural problems. Whereas the effects of lead exposure on child behaviour are well studied, the potential familial effects remain unexplored. Lead exposed children have been described as hyperactive, impulsive, oppositional, even delinquent. Interacting with such children might be difficult for parents and siblings. Elevated BLLs in mothers or children have been associated with maternal perception of difficulty with setting limits or discipline. To complicate matters, elevated BLLs in adults are also associated with irritability, fatigue, and depression, and with deficits in problem-solving and impulse control. Thus, not only could lead exposed children behave differently in family interactions, but parents and siblings could exhibit different patterns of behaviour towards these children.

Aims & Objectives
There are no studies to help us understand the relationships among lead exposed parent-child dyads/triads or wider families. Therefore, the goal of this research is to examine how the family’s exposure to lead affects their behaviour and subsequently the child’s neurobehavioural outcomes, and whether the family’s interactions could serve as target for eventual behavioural intervention.

Methods
Using data from the Avon Longitudinal Study of Parents and Children (ALSPAC), the student will develop statistical analyses around the links between early exposure to lead (and other toxicants if desired) and parent-child and sibling relationships. Parent reports of these relationships as well as objective measures of parent-child interactions are available. Subsequent analyses may include functional outcomes in children, such as achievement of developmental outcomes, cognition and behaviour, and may draw upon structural equation modelling. The project may include may incorporate other social or biological factors, such aspects of the social environment of the home or genetic underpinnings of behavioural traits.