The air intake of a resting infant is twice that of an adult under the same conditions. The typical nature of children's behavior also increases their exposure to environmental toxicants. An infant frequently explores objects by placing them in his or her mouth. With considerable physical energy, children can explore locations without regard for the consequences of their actions. At rest, children's breathing rates are faster than those of adults, and children's greater levels of physical activity can increase their breathing rates even further.
Children often play at ground level.
In contrast, an adult's common breathing zone is four to six feet above the floor. Children will receive greater inhalation and dermal exposure to chemicals present on floors, carpet, grass, or dirt. Also, heavier chemicals such as lead and particulates will settle and accumulate in the air at ground level. Childhood is characterized by rapid physical and mental growth. Accordingly, certain organs may not be fully developed and may be more vulnerable to injury.