Atrazine is a ubiquitous, persistent, and highly mobile contaminant
Atrazine is the second largest selling pesticide in the world (largest up until 2001) [1-5]. It is an herbicide (weed-killer) used primarily on corn, but also on crops such as sorghum, sugar cane, and Christmas trees. Also of note, it is used in forestry after tree harvesting . Approximately 80 million pounds of atrazine are applied annually in the US, primarily in corn growing states such as Nebraska, Iowa, Kansas, Illinois, Indiana and Ohio, but significant amounts are used in all but six states .
Figure 1. Map showing distribution of atrazine-use by state. Atrazine use by crop is also shown. Map courtesy of United States Geological Service (USGS).
Atrazine is the most common pesticide contaminant of ground and surface water [2, 4, 8-24]. It is also highly mobile and can travel in rainwater [24-26]. A half million pounds of atrazine return to the earth in rainfall and snow in the United States every year. Studies in both the US and in Europe have shown that atrazine can travel as much as 600 miles from the point of application, contaminating even otherwise pristine habitats [24, 27-29]. Atrazine is also highly persistent and remains in groundwater in the US even during times of the year when it is not applied . Further, atrazine has persisted in groundwater in France, even though it has not been applied there for 15 years . Thus, even if atrazine use was stopped today, it would be another generation (at least) before the environment is atrazine-free.