What is the highest level of contaminant in drinking water that poses no known health risk?

The highest level of contaminant in drinking water that poses no known health risk is established as the Maximum Contaminant Level Goal. This guideline represents a non-enforceable health goal set by regulatory agencies, such as the Environmental Protection Agency (EPA). It provides a level of contaminants that is deemed safe for human health over a lifetime of exposure, taking into account a margin of safety to protect sensitive populations.

The focus of the Maximum Contaminant Level Goal is on public health protection, emphasizing that no adverse health effects would be expected if these levels are maintained. This makes it a critical standard in evaluating drinking water safety.

Other options, such as the Maximum Contaminant Level, represent legally enforceable limits but may not necessarily reflect the absence of all health risks. The Maximum Safety Threshold and Minimum Risk Limit are terms that do not align with established drinking water standards in the same way, making them less relevant to this specific question regarding safe drinking water guidelines.