All you need to know about manganese

Manganese is a naturally occurring mineral in the environment, and it’s also a very abundant metal found in water, soil, air, and on the earth’s surface. Human activities like industrial discharges and mining have caused manganese to spread to both surface water and groundwater though in some cases, the mineral deposits come from natural sources. Manganese is used in several manufacturing industries such as livestock feeding supplements, steel, and iron alloy, fireworks, glass, batteries, fertilizers, glass, fireworks, varnish, cleaning supplies, fungicides, and cosmetics.

Drinking water exposes the human body to manganese. Increased manganese concentrations occur mainly in water from private wells and municipal water. Generally, there is a high prevalence of manganese in groundwater more than in surface water. Though we can get exposed to manganese through food, the bioavailability, that is, the amount absorbed by your body is more prevalent in drinking water.

Impact of Manganese on Drinking Water

Manganese is a vital nutrient, though it should be taken in low doses. High levels of the mineral in the body are a health concern. The health impacts of manganese depend on many factors like age at exposure, chemical form, route of exposure, and the individual’s nutritional status.

According to research studies, drinking water containing high manganese levels may lead to neurological problems in children and infants. These problems include limited coordination and movement control, memory ad speech difficulties, low IQ, and changes in behavior. There are also aesthetic issues associated with manganese in drinking water, such as stains on laundry, plumbing fixtures, toilets, and tubs/showers. It may also cause the water to taste metallic.



How to detect manganese in drinking water

In Canada, the maximum acceptable concentration for manganese is 0.12mg/L, with 0.02mg/L aesthetic being the objective in drinking water supplies. Health Canada set this standard in 2019. The federal government recommends that if you have a well have your tested yearly for manganese to be on the safe side. Water Treatment companies have testing equipment that can detect manganese as well and be able to have a look through your home for any staining associated with manganese. You can find all of Canada’s guidelines here:  

Guidelines for Canadian Drinking Water Quality: Guideline Technical Document – Manganese

The World Health Organization has an HBV (health-based value) of 0.4 mg/L but didn’t think it was not necessary to establish a formal drinking water guideline for manganese since the HBV is well above concentrations normally found in drinking water.

 In the United States, public water systems do not test for manganese under the Safe Drinking Water Act. The federal government does not enforce maximum contaminant levels for manganese in drinking water. Even so, EPA has set National Secondary Drinking Water Regulations that assess water quality standards that are non-mandatory. These guidelines help water systems manage drinking water while at the same time considering the aesthetics such as odor, color, and taste. The set secondary maximum contaminant level for manganese is 0.05mg/L which protects against water that tastes bitter and metallic and has black stains.

In 2004, EPA established a level of 0.3mg/L for chronic manganese exposure. This standard is a non-enforceable lifetime health advisory. For acute exposure, the health advisory level is 1 day and 10-day 1mg/L. For infants aged six months or lower, the EPA has set the chronic and acute exposure to 0.3mg/L. These advisory levels serve as guidelines that aid regulatory officials and help them protect public health and address manganese contamination.

Manganese Mobile Test Kit

Manganese Mobile Test Kit

How do you get rid of manganese from your water?

You can remove manganese from drinking water using water treatment technologies such as reverse osmosis, filtration, distillation, and cation exchange water softening. If you want an additional assurance level for protection from manganese, you can go through the product certification process. This process is a review of confidential information by the Certification Body. This body reviews the location where the product is built and labeled as well as how it’s made.

The organization also examines suppliers for each component and material and conducts regular audits in the manufacturing unit to ensure that the product is not altered without retesting or authorization. It also conveys essential information to consumers by reviewing product labeling and packaging. Lastly, the organization administers additional testing to the water to ensure that no leaks are developed because of pressure spikes. Product certification for manganese reduction to 0.5mg/L is obtainable for reverse osmosis, filtration, distillation, and cation exchange.

Control Valve

Control Valve

Manganese in well water

Manganese may be found in high levels in your well water. Eliminating the mineral will depend on three factors: other minerals’ presence, the oxidation state, and the total dissolved solids. It may be challenging to eliminate if manganese appears with iron or hydrogen sulfide.

If you want to detect manganese in your water, examine your dishwasher because the detergent increases the pH in the water to a high level that allows the mineral to precipitate. You can also investigate toilet tanks and check if a floating film appears on the surface of the water. This is a sign that the mineral is present.

Manganese In The Pipes

Manganese In The Pipes

Using a filter to remove manganese

Precipitation needs to occur before a filter removes manganese. The filter will need a high pH reading and oxygen content. Different filter mediums have different requirements though they all need a pH greater than 8 to function effectively. Moreover, the filter will need oxidizers such as potassium permanganate, ozone, or chlorine during pretreatment. Filtering manganese from water may be a simple process using a granular medium, or it may be more complicated, requiring more operations that involve adjusting the pH and working with an oxidizer.

A simple cartridge-style sediment filter may be all you need to remove manganese. If the mineral content is high, you should use a backwashing filter that contains multi-media like garnet, sand, or anthracite and a suitable sediment reduction medium.

You can also use the media in the filter as catalysts to convert soluble manganese to an insoluble solid, especially when there is a relatively low mineral concentration and high pH and oxygen content level.

Sometimes you may need to use pretreatment or oxidation filters. These are free-standing oxidizers that may also involve enhancing the pH. The pretreatment is conducted through aeration, chlorination, or adding potassium permanganate. To learn more about this manganese check out this Video.

Manganese Stained Dishwasher

Manganese Stained Dishwasher

Using a water softener to remove manganese

A water softener is not an ideal tool for eliminating manganese in drinking water. This is because a softener accommodates high levels of manganese in its unprecipitated state. A softener works best when the amount of total dissolved solids is low in the water, there is low dissolved oxygen content, and the pH level is high. Using a softener to remove manganese is not recommended as minerals will build up and foul the resin bed.