Due to their small size, children are at greater risk from exposure to toxic chemicals. Children eat, drink, and breathe more per pound than adults do. Also, children, especially the very young, are more susceptible to toxic chemicals because their organs are still rapidly developing, and growing organs are more vulnerable than mature organs and tissues. For example, the brain is not fully developed until the late teens, and grows especially rapidly during the first seven years of life. A toxic hit to the brain while it is forming can have more serious effects than one later in life.
During infancy, the immature liver can not yet metabolize toxic agents as well as it will later in life. This is why the half-life of caffeine—the time required to reduce the substance to half its initial amount—can be measured in days for a newborn but in hours for an adult.
image from Cristyan González Alfonso at
Creative Commons. modified
In addition to these physiological differences, children also behave in ways that increase their exposure to toxic agents in their environment: they play on the floor or ground, they put their hands in their mouths, and they actively investigate their surroundings. Combined with their low body weight, higher relative intake of food, water, and air, and their developmental stage, these behavioral factors contribute to elevated risks.
image from Honza Soukup
at Creative Commons, modified
For a long time, the placenta was thought to protect the developing fetus significant from hazardous agents. We know now that the majority of agents readily cross the placenta and expose the developing fetus to whatever foods and chemicals circulate through the mother's body. For compounds that readily distribute throughout body liquids, the amniotic fluid surrounding the infant will have the at least the same level of the compounds as the mother's blood. Fetal exposure to methylmercury can actually be higher than the mother's because the developing infant acts as a storage site for maternal mercury.
Many children's products may contain toxic chemicals. As just one example, many disposable diapers contain polyacrylic acid that can cause allergic reactions, from a rash to lesions. Many dyes linked to allergic reactions are also found in diapers. Diaper materials bleached with chlorine create small amounts of dioxin, a potential human carcinogen. See more information about baby products in CHE's Practice Prevention: Baby Care Products.
CHE's fact sheets and publications related to children's health are listed at right, along with several recommended sources of more information.
* header image by Michael Verhoef from Creative Commons