Atrazine is an organic compound which is widely used as a herbicide. Its use is controversial due to its effects on nontarget species, such as on amphibians. Its use was banned in the European Union in 2004 but it remains one of the most widely used herbicides in the U.S. . 
Atrazine was first used in the United States in 1959 where it currently still is one of the most widely used agricultural pesticides, with an annual production of over 35.000 tonnes. It is mainly used in sorghum, corn and sugarcane cultivation. It is released in the environment both from production sites as from its use as a herbicide.
Atrazine has a moderate water solubility of 30 mg/l and is therefore quite mobile the environment. It is also persistent with a half-life in water of 150 days, and an even longer one in the soil. It has a relatively low tendency to adsorb to soils or particles. Therefore, atrazine is expected to be present in surface water and groundwater. It also has a low tendency to evaporate to the atmosphere and might afterwards be deposited by rainfall, although it is rapidly degraded in the atmosphere.
Atrazine has a moderate toxicity in crustaceans and fish; concentrations above 3mg/l are necessary to induce acute lethal effects. Some fish and crustacean species can even tolerate atrazine concentrations above 80 mg/l. Phytoplankton is more vulnerable as toxic effects occur at concentrations of only 60 µg/l. There have been reports that low concentrations of only 20 µg/l could change the behaviour of amphibians. Atrazine has also been suspected to induce endocrine disrupting effects in amphibians and mammals. 
Environmental standards and legislation