Mercury

What is It?

-Mercury is a naturally occurring metal which has several forms in the environment.

-Mercury may combine with other elements, such as chlorine, sulfur and oxygen to form Mercury salts.

-The most common Mercury salt: methyl-mercury, is produced mainly as a by-product of microscopic organisms in the water.

-More Mercury in an environment leads to the increased presence of methyl-mercury resulting from these micro-organisms.

-Methyl-mercury builds up in the tissues of fish.

-Large, predatory fish tend to have the highest levels of mercury in their tissues.

Why is it in the environment?

-Mercury enters the water through disposal of industrial wastes.

-Combustion of fossil fuels, landfills, as well as metal refineries release Mercury.

How does it affect water quality?

-Contaminates clean drinking water, causing it to be poisonous.

How does it affect adults?

-The nervous system is susceptible to all forms of mercury.

-Although, Methyl-mercury is the most harmful form of Mercury.

-Exposure to high levels of Mercury may damage the brain and kidneys.

-Symptoms include: irritability, shyness, tremors, changes in vision or hearing, and memory problems.

-Short-term exposure to Mercury is not as severe as the Mercury poisoning takes many years to develop symptoms.

How does it affect children?

-Young children are more sensitive to mercury than adults.

-Mercury may pass to a nursing infant through a mother’s breast milk.

-Other harmful effects are: brain damage, mental retardation, blindness, seizures, and impaired speech.

-Long term Mercury poisoning may develop problems with nervous systems, digestive systems and kidney damage similar to adults.

What are the EPA regulations?

-The EPA has set a limit of 2 parts of mercury per billion parts of drinking water (2 ppb).

-The Food and Drug Administration (FDA) has set a maximum permissible level of 1 part of methyl-mercury in a million parts of seafood (1 ppm).

-MCL: 2 ppb

-MCL: 0.002 mg/L