What is considered a secondary drinking water regulation limit for manganese?

The correct limit for manganese as a secondary drinking water regulation is set at 0.05 mg/L. Secondary drinking water regulations are primarily concerned with aesthetic effects, such as taste, odor, and color, rather than direct health effects, which are covered by primary regulations. Manganese can impart a bitter taste and can also lead to staining of laundry and plumbing fixtures if present in high concentrations. The established limit of 0.05 mg/L reflects a balance between protecting public health and minimizing disturbances related to manganese in drinking water. This value is aligned with federal guidelines set by the Environmental Protection Agency (EPA) to ensure that water sources do not adversely affect the quality of life for consumers.