Mercury is a naturally occurring ubiquitous element that is found in air, water and soil and is toxic to living organisms. One form of naturally occurring mercury is cinnabar ore, primarily composed of mercuric sulfide. Because it is the only heavy metal that exists as a liquid at room temperature, has high electrical conductivity, and alloys with other metals it has been used in many industrial, agricultural, medical and household applications. Elemental mercury itself can be toxic especially if inhaled, but this element can also be methylated by microorganisms in aquatic systems into an even more toxic organic form, methylmercury. Methylmercury is highly bio-accumulative and persistent in fish tissue. Because of this many states have published “Fish Consumption Advisories”. Most of the mercury, which enters water, comes from household and industrial wastes released during incineration, latex paint, and from burning coal and other fossil fuels.

The toxicity and use of mercury has been known for centuries. It has been recognized as an environmental pollutant of concern for decades. Prolonged or chronic exposure to mercury may cause damaging health effects. The adverse health effects are dependent on the form of mercury the individual is exposed to, the dose and the exposure route.



Minnesota Fish Consumption Advisory Program

MN Department of Natural Resources Fish Consumption Advisory