What is the Maximum Contaminant Level (MCL) set for arsenic in drinking water?

The Maximum Contaminant Level (MCL) for arsenic in drinking water is set at 10 µg/L. This standard is established by the Environmental Protection Agency (EPA) to protect public health, as arsenic is a well-known toxicant and can lead to serious health issues, including cancer and skin lesions, as well as developmental effects, cardiovascular disease, neurotoxicity, and diabetes.

Setting the MCL at 10 µg/L is based on extensive research on the health impacts of arsenic exposure and aims to minimize the risk to consumers while considering the feasibility of achieving this level in water treatment processes. This limit reflects a balance between health protection and practical water treatment capabilities.

In context, the other options present thresholds that are either less protective or do not conform to established guidelines for arsenic levels in drinking water. The MCL for arsenic at 10 µg/L thus represents a scientifically determined and regulatory-backed level of safety for public water supplies, ensuring safer drinking water for the population.