ABSTRACT
In 1993, the National Academy of Scientists cited qualitative and quantitative differences in the toxicity of pesticides between children and adults and concluded that children cannot be merely considered “little adults” in terms of their biological response to chemicals (National Research Council 1993). This landmark report provided the impetus for the passage of legislation that contributed to stricter safety standards for infants and children, such as the Food Quality Protection Act (1996). In recognition of the existing differences in the biological responses to chemical exposures between children and adults, U.S. federal agencies developed regulatory guidelines that focused on the developing life stages that encompassed the prenatal time period through adolescence. Infants, dened as 12 months of age or younger, represent a subpopulation of interest based on exposure and biological factors. As an example, infants predominantly consume a single source of nutrition (i.e., sole-source consumers) for at least the rst 6 months after birth, relying on breast milk and/ or infant formula for sustenance, which potentially increases their exposure to chemicals migrating from one packaging type into expressed breast milk or formula. Furthermore, infants consume more food per kilogram body weight per day than adults, which may also raise their exposure to dietary exposure to chemicals. Other factors that alter exposure paradigms for infants compared to other life stages include increased mouthing behavior and elevated respiration rates. Finally, infants undergo rapid biological maturation and exhibit different physiologies from adults that may impact their potential sensitivity to chemical exposures. The aim of this chapter is to introduce current standardized protocols used to assess the safety of products for infants, to provide a critical evaluation of their strengths and weaknesses, and to propose some changes that may bridge existing gaps in these study paradigms. To accomplish these objectives, we will provide an overview of the biological differences that are known between infants and adults, discuss potential sensitivities particular to infants, and review current protocols that provide pertinent information for the safety assessment of infant products when conducted by researchers. We will end with our recommendations to optimize these current guidelines in the context of the safety assessment of products for infants.
