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What’s the Maximum Amount of Mercury Allowed in Drinking Water?

Mercury is that mysterious element that only exists in thermometers and sci-fi movies, right? Sadly, mercury is created by plenty of natural and synthetic processes, many of which can cause trace (or large) amounts of mercury to leak into drinking water sources. But how harmful is it, exactly?

Mercury in its pure elemental form can be released during industrial and agricultural processes and then disperse via sewage systems connected to water sources. Mercury vapor in its elemental form, when experienced in high concentrations, can cause nervous system damage.

Mercury is most commonly found in drinking water in the form of inorganic mercury, the substance found in batteries and other chemical industrial products. While inorganic mercury can cause kidney damage when absorbed through other means, generally this type of mercury is considered to be safe for human consumption in water in small quantities.

mercury in drinking water

The real trouble arises when bacterial organisms found in surface waters convert inorganic mercury into organic mercury. This form of mercury poses a significant risk to human health, especially when ingested by children. Methyl mercury, a form of organic mercury, is found in high concentrations in some fish, which can cause issues with water treatment plants depending on their cleaning and treatment methods.

The EPA established the Safe Drinking Water Act in 1974 to establish guidelines and regulations on the various amounts of contaminants allowing in drinking water fit for consumption. Surprisingly, mercury was not monitored or regulated on a national level until 1992, many years later.

Once proper testing was done on mercury’s health risks, the acceptable level was set at an incredibly low level. Mercury, even in trace amounts, is invariably harmful and dangerous. At that time the Maximum Contaminant Level was set at 2 parts per billion and has not moved since then.

The technology utilized to monitor the public’s drinking water in America allows suppliers to theoretically detect and remove mercury from the water in a treatment facility at the parts per billion level. However, as is evidenced in Flint, Michigan, the effectiveness of water treatment in any region is only as strong as the infrastructure and governmental agencies in charge of the treatment process.

The EPA requires that local agencies monitor the mercury content in public drinking water every 3 months to remain in accordance with the Safe Drinking Water Act once high levels of mercury are detected. The measures that must be taken with persistently high mercury levels can take months to implement, at which point some damage may have already occurred.

One of the only approved methods of effectively removing mercury from your home’s drinking water is through reverse osmosis filtration. To properly protect your family’s ongoing health, invest in an NSF certified Reverse Osmosis filtration system from Pelican Water. Mercury, even in miniscule amounts, can cause permanent health issues if consumed.

Disclaimer: The information on this website has not been reviewed by the FDA. Products offered for sale herein are not intended to treat, cure or prevent any disease or health condition. No medical claims are being made or implied. Contaminants mentioned are not necessarily in your water.


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