Developmental toxicology and children's environmental health
Developmental toxicology is the study of toxic exposures in early life and their impacts on health and development. It employs a combination of experimental and human studies. Early development from zygote, through gestation, infancy, childhood, and adolescence is a highly vulnerable period. Exposures to environmental toxicants in early development can disrupt developmental processes and result in lifelong functional impairment. The timing of exposure is of critical importance. Early development is also a time of enhanced exposures to toxic substances because of sole-source nutrition and hand-to-mouth behavior. Even low-level exposures to environmental toxicants can be deleterious when they occur on a population-wide scale and result in widespread impairment. The consequences of developmental toxicity are not restricted to children. The entire population has progressed through development, and people of all ages can bear lifelong impacts of early toxic events.