Final answer:
Iron toxicity can cause serious health issues like liver damage and heart problems. The Code of Federal Regulations sets specific allowable limits for contaminants in drinking water, such as iron (0.3 mg/L), zinc (5 mg/L), copper (1.3 mg/L), and lead (0.015 mg/L), based on the differing toxicity levels of each chemical species.
Step-by-step explanation:
Iron toxicity occurs when there is an excessive accumulation of iron in the body, which can lead to a condition known as hemochromatosis. The health effects of too much iron include liver damage, heart problems, diabetes, and arthritis. The Code of Federal Regulations specifies the allowable limits for various substances in drinking water to ensure safety and health. For iron, the Secondary Maximum Contaminant Level (SMCL) is set at 0.3 milligrams per liter (mg/L). Similarly, the allowable limit for zinc is 5 mg/L, for copper is 1.3 mg/L, and for lead, it is 0.015 mg/L.
The different chemical species have very different allowable limits because each one can have varying levels of toxicity, effects on health, and potential for accumulation in the body. Thus, regulations are set based on the risk assessment of each contaminant's potential for harm to human health.