Iron and Manganese


What is Iron and Manganese?

Iron (chemical symbol “Fe”) and Manganese (chemical symbol “Mn”) are naturally occurring elements and are primarily regulated for aesthetic and economic (i.e. damaging effects of corrosion, scaling, staining, and sedimentation) purposes. Both are noted as imparting a taste and color to drinking water. A brownish color to laundered clothing and staining (brown, rusty/orange, black) of plumbing fixtures are common indicators. Also, iron and manganese contribute to the cause “hard” water which necessitates the use of larger amounts of soap to form suds and responsible for scaly deposits in pipes and water heaters. Iron bacteria can be a real nuisance. These bacteria can form slime growths that utilize the iron in the water as a source of energy.

How is Iron and Manganese tested?
A properly collected and preserved (with Nitric Acid) sample must be obtained. The “holding time” (i.e., time which iron and manganese must be analyzed after sample collection) is 6 months. There are a few NJDEP certified test methods for iron and manganese including Atomic Absorption (AA) and Inductively Coupled Plasma (ICP). The detection limits vary by method and instrumentation, however the Reporting Limits need to be less than Recommended Upper Limits.

What are the current Standards?
Iron and Manganese are constituents classified as “secondary” standards (aesthetic) and have Recommended Upper Limits of 0.3 ppm (mg/L – milligrams per Liter) for Iron and 0.05 ppm for Manganese.

What are the potential Health Effects with ingesting Iron and Manganese in water?
These elements are not known to directly affect health.

Should I continue to use my water if Iron and Manganese are found above the limits?
To be sure, you should consult with the local health agency.

What steps can I take to reduce Iron and Manganese levels in my water?
Short term: bottled water
Long term: 1.) Connect to public water 2.) Well replacement 3.) Water Treatment: Point of Entry Treatment System (POET) such as air stripping (with filtration), distillation, oxidation, ion exchange, and reverse osmosis. Iron bacteria can be killed with chlorine. 4.) Contact you local Health Agency and a Water Treatment Professional.

If you install a water treatment system, be sure to conduct another test after the water has been treated to verify that the system is working effectively.

Where can I go for more information?
Your best help may be your local Health Agency. Also, go to the Helpful Links section of this website.


This information is meant to serve as a basic overview of the material discussed. Always obtain professional advice prior to implementing a plan of action.