Mercury


What is Mercury?
Mercury is a shiny, silver-white metal (chemical symbol “Hg”) found in small amounts in the earth’s crust. Mercury is toxic to living organisms. Mercury exists as metallic mercury (such as is used in thermometers), inorganic mercury (such as mercuric chloride and used in batteries, paper manufacturing, mercury-based pesticides, and chemical industries), as well as organic mercury (such as methyl mercury – volatile, water soluble, highly toxic and found in large fish such as bass, sharks, tuna, and swordfish). Mercury, carried by wind and rain, is found throughout the environment mostly due to man-made releases such as burning of coal and oil, incineration, and applications of pesticides. Other sources include improperly disposed household products, such as mercury containing outdoor paints.

How is Mercury tested?
A properly collected and preserved (with Nitric Acid) sample must be obtained. The “holding time” (i.e., time which mercury must be analyzed after sample collection) is 28 days. There are a two NJDEP certified test methods for mercury – a Cold Vapor Atomic Absorption (AA) Technique and Inductively Coupled Plasma (ICP)/MS method. The detection limits vary by method and instrumentation. The test method must achieve a detection limit lower than the Maximum Contaminant Level (MCL).

What is the current Standard?
Mercury is a constituent classified as a “primary” standard and has a Maximum Contaminant Level (MCL) of 2 ppb (ug/L – micrograms per Liter).

What are the potential Health Effects with ingesting Mercury in water?
Potential health effects include kidney and nervous system disorders. Inorganic mercury is poorly absorbed through the gastro-intestinal tract. Young children are more sensitive than adults to inorganic mercury since it is more easily absorbed into their bodies. At high exposure, inorganic mercury can affect the renal system as well as the nervous system causing symptoms such as irritability, nervousness, changes in vision or hearing, and difficulties with memory.

Should I continue to use my water if Mercury is found above the MCL?
The answer is no for drinking water consumption. You should alert the local health agency and follow their advice. Also, do not boil water as a method of treatment because this can release certain forms of mercury into the air and can increase the levels of inorganic mercury as the water evaporates.

What steps can I take to reduce Mercury levels in my water?
Short Term:
purchase bottled water.
Long Term: 1.) Connect to public water 2.) Well replacement 3.) Water Treatment: Point of Entry Treatment System (POET) or Point of Use (POU) Treatment System such as KDF-55 with pH adjustment, distillation and reverse osmosis for inorganic mercury and granulated activated carbon for organic mercury. 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.

What can I do to help prevent mercury pollution?
Once mercury is released it is difficult to remove, so the best practice is to prevent mercury from entering the environment. Hence, do not buy mercury-containing items if a substitute is available. Properly dispose of or recycle Mercury containing products such as thermometers, batteries, paint and pesticides.

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.