Mercury is a highly toxic element that becomes an air pollutant largely through emissions from coal-fired power plants. It is also broken free from rock and soil by acidic water. Small amounts are also contained in the same smoke that causes acid rain. Mercury can collect in the body tissue of fish. This build-up of mercury has major health implications not only for fish, but also other species that consume them. Birds such as loons, ducks, eagles, herons, and others consume large quantities of fish. Mammals such as fishers, bears and people are also at risk.

Mercury Facts

  • Mercury levels are high and pervasive in northeastern North America, including the Adirondacks.
  • New research shows that many animals, even forest songbirds, have elevated mercury burdens. Based on these findings, it is increasingly clear that mercury can no longer be viewed as strictly an aquatic pollutant.
  • Mercury is an element that is found in rocks in the earth's crust. Through mining and industrial processes, mercury is brought to the earth's surface and used in manufacturing, electricity generation and consumer products (such as lamps, thermometers and dental material). Eventually, the mercury is emitted to the air or discharged to water as a byproduct of combustion or improper waste disposal. Once in air and water, mercury presents a risk to ecological and human health." **
  • Mercury is a neurotoxin. Adults, children, and developing fetuses are at risk from ingestion exposure to mercury. The most common way people are exposed to any form of mercury is by eating fish containing mercury. *
  • Once in the human body, mercury interferes with the brain and nervous system. Prenatal or early infant exposure to mercury can cause a host of health issues in humans including mental retardation, cerebral palsy, deafness, blindness, developmental disorders which can delay motor and communication skills, and learning disabilities. Scientists are now studying links between mercury exposure and autism. Adult exposure can cause memory and vision loss, tremors, and numbness in extremities. Scientists are also studying links between mercury and heart disease. **

* EPA website
** NRDC website

Federal Mercury Regulations

On March 16, 2011, the U.S. EPA released its proposed rule for mercury and other air toxics. It was finalized by the EPA in December 2011.  A copy of the Adirondack Council’s comments on can be found here.  

This rule, now known as the Mercury and Air Toxics Standards, or MATS, for the first time ever, would mandate reductions in mercury emissions from coal-fired power plants. The roughly 90 percent reductions over the next three years and will have substantial human health and environmental benefits.

This rule would replace the Clean Air Mercury Rule, which was proposed in 2005 and thrown out by the courts in 2008.  More details about MATS can be found at

Department of Health Mercury Warning

The NYS Dept. of Health issued a warning in April 2005 urging that women of child-bearing age and children younger than 15 avoid eating northern pike, pickerel, walleye, largemouth bass, smallmouth bass and larger yellow perch from all waters in the Adirondack and Catskill mountain regions because of mercury contamination.

Neither region receives more mercury deposition from smokestacks than any other part of New York, but acid rain problems in both parks accelerate the absorption of mercury into fish.

As acid rain subsides over the next few decades due to new state and State Mercury Warnings Expanded federal regulations, the leaching of mercury from soil and decaying plants will subside as well. But people are advised to wait until the warnings are withdrawn before resuming a steady diet of Adirondack or Catskill predatory fish. Loons, mink, otters, migratory birds and other fish-eating wildlife are harmed by mercury as well. Trout, catfish, smelt and other popular food fish have not been found to have elevated mercury levels. Mercury can effect a developing nervous system as well as the development of organs in a fetus, infants and young children. Some of the contaminants may also build up in women and may be passed on during breast feeding, according to the state Health Department.