A tiered approach to assessing children's exposure: a review of methods and data

From a public health view, there are many important issues to improving children's and adolescent's health, for example, prenatal and childhood nutrition, immunizations, infectious disease control, and drug/alcohol/tobacco control. There has been increasing emphasis worldwide on protecting children from adverse health effects due to environmental factors, including chemicals. For well-studied contaminants (e.g. lead) the risks to children are reasonably known and appropriate risk management actions, in a public health context, can be undertaken. For a number of other chemicals, hazard and exposure data are less complete, and risk-based priorities are consequently less substantive. The US EPA's Voluntary Children's Chemical Evaluation Program proposal prompted additional efforts to develop and improve methods and data for assessing children's exposure. The goal is to efficiently identify the substances and conditions that present the highest potential risks to children, so that resources can be applied efficiently to assure their health improvement. The methods we illustrate use an iterative (tiered) approach for (a) screening level and (b) more detailed exposure assessments relevant to children. We also review and reference the key information sources available for such assessments and analyze the information and method's strengths and limitations.