SACRAMENTO, Calif. – The State Water Resources Control Board is lowering the notification and response levels for manganese in drinking water based on data evaluating potential health risks to formula-fed infants.
Public water systems must now take certain actions when manganese levels are exceeded.
Notification and response levels are non-regulatory health-based thresholds used for contaminants that do not currently have a state-established primary maximum contaminant level. Public notification or additional actions may be warranted to reduce exposure.
Manganese is a naturally-occurring trace mineral that can lead to neurological issues at high levels in drinking water. It can also cause discoloration of water, plumbing fixtures and laundry.
The revised health-based notification level for manganese is 0.05 milligrams per liter. The revised response level is 0.20 milligrams per liter.
When water sampling indicates that manganese exceeds the new notification level, water systems must notify their governing body within 30 days.
When sampling indicates an exceedance of the manganese response level, water systems must now notify customers to use an alternative water source, such as bottled water, when preparing infant formula.
Officials say that as the first step toward establishing a primary maximum contaminant level for manganese, the State Water Board has requested that the Office of Environmental Health Hazard Assessment develop a Public Health Goal for manganese.
More information about manganese and drinking water notification and response levels is available on the State Water Board’s website.