Children's environmental health is a growing, interdisciplinary field of diverse professionals and community members working together in policy advocacy, research, health, and environmental interventions and treatment services. Understanding exposure assessment is central to improving children's health across age, gender, indicators of socioeconomic status, and racial/ethnic groups. In general, children are more susceptible and vulnerable to adverse acute and chronic effects due to acute and chronic exposures to environmental toxicants since they eat more food, drink more fluids, and breathe in more air per unit of body weight than adults; their behaviors and rapid developmental changes also contribute to their risks. By enhancing knowledge and awareness of the basic concepts of human exposure assessment and key details of sources of environmental pollution, pediatric nursing professionals can enhance their practices--clinical and patient education skills--and thus improve daily work in their communities through the promotion of exposure reduction or prevention measures.