Final answer:
Infants have a higher risk of drug toxicity compared to adults due to their increased body fat percentage, underdeveloped organ systems, and exposure to various environmental and teratogenic substances, which their immature systems are less capable of metabolizing.
Step-by-step explanation:
Compared to adults, infants are at a greater risk for drug toxicity due to their increased percentage of total body fat. This impacts how drugs are metabolized and stored in the body, leading to higher susceptibility to the adverse effects of drugs and chemicals. An infant's body is still developing, which includes the maturation of organs like the liver and kidneys that are fundamental in processing substances.
Furthermore, exposure to teratogenic substances such as heroin, cocaine, and prescription medications during pregnancy can lead to dependence and require medical intervention post-birth. The vulnerability of infants also extends to environmental factors, as evidenced by research indicating that a newborn's cord blood contains various industrial compounds, some of which are linked to neurological and immune system toxicity. During infancy, the body's defenses and mechanisms for dealing with external toxins are not fully formed, contributing to the higher risk of drug toxicity in this age group.