Note: EPA no longer updates this information, but it may be useful as a reference or resource.
What is Mirex?
The insecticide mirex was used for 16 years (1962-1978) in the Southeastern United States to control the imported fire ant. Eight of the infested states border on the Atlantic Ocean or the Gulf of Mexico or both, making fire ant control programs an issue in the use and management of estuaries. Mirex as a control chemical for fire ants became controversial when it was found to be highly toxic to a variety of marine crustaceans, including commercially important species of shrimps and crabs. Extensive public hearings were held during the period 1973-1976. All uses of mirex were cancelled in 1978. This chemical is usually seen as a snow-white crystalline solid, is odorless, and does not burn easily. When mirex does break down, it turns into photomirex, which also can have harmful health effects. Mirex has been listed as a persistent, bioacculumative, and toxic (PBT) pollutants target by EPA.
Why Are We Concerned About Mirex?
Because mirex is bioaccumulative, it does not break down easily in our environment. This is why mirex is still found in our environment after being banned. Mirex becomes more concentrated as it moves up the food chain to humans and other animals. Mirex is not broken down in the body and is stored in our fat.
What harmful effects can Mirex (Dechlorane) have on us?
- Classified by the EPA as probably causing cancer in humans
- Harmful effects on stomach and intestines
- Damages the liver and kidneys
- Harms the eyes and thyroid gland
- Causes damage to the nervous system and the reproductive system
- May be the cause of increased miscarriages
How are we exposed to Mirex (Dechlorane)?
- Infants may exposed through breast milk
- Eating contaminated fish and shellfish
- To some extent it may be in drinking water
Where can Mirex (Dechlorane) be found?
Although the sale, distribution, and use of mirex is prohibited in the United States, it is still found in our environment.
- Widely used in the Southeast to kill fire ants
- Commonly used as a fire retardant in plastics, rubber, paint, paper, and electrical goods
Potential Sources to our Environment:
- Contaminated bottom sediments in water ways
- Surface water contamination, sediments
- Clean up and removal of contaminated soil