What is the maximum contaminant level (MCL) goal for known or probable carcinogens?

The maximum contaminant level (MCL) goal for known or probable carcinogens is set at zero. This reflects the understanding that exposure to substances known or likely to cause cancer should be entirely eliminated whenever possible, as even the smallest amounts could pose a risk to human health. The goal is to ensure that drinking water is as safe as possible and that potential risks from carcinogens are minimized.

Establishing an MCL goal of zero for carcinogens emphasizes a precautionary principle in public health, prioritizing the protection of the community and aiming for no permissible level of contamination for these hazardous substances. This approach aligns with broader regulatory frameworks where public health takes precedence, recognizing that some contaminants pose a direct threat to human health even at very low concentrations.