Male frogs in the Louisiana Atchafalaya Basin and in other rivers and streams around the state are turning female. Scientists believe it's because of a pesticide that's been used in Louisiana and around the world since 1958.

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Atrazine was officially classified as a herbicide in the late 1950s. The triazine class herbicide is used for broadleaf weed control. Farmers in Louisiana have been using atrazine on corn and sugarcane crops for decades. Today atrazine is also used on lawns, golf courses and even Christmas tree lots.

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The herbicide is made by Syngenta and is mainly distributed in the United States and Australia.

In 2012, Syngenta was hit with a class-action lawsuit over the levels of the pesticide atrazine in human water supplies and agreed to pay $105 million to over one thousand water systems as reimbursement for having to filter out atrazine from their local community water systems. To this day, Syngenta claims the company did not act irresponsibly and takes no credit for any wrongdoing, according to

Atrazine has run off into Louisiana waterways since the early 1960s. Today, if you were to test frogs in the state's Atchafalaya Basin, you'd find a large percentage of female frogs, that were genetically born male. Studies have shown atrazine is an endocrine disruptor altering the natural hormonal system of frogs and, in higher doses, in human's as well.

Male frogs are turning female and giving birth to only male frogs. Eventually, the species will die.

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It's important to note, atrazine is also used throughout the Midwest and makes it way down the Mississippi River into Louisiana.

The herbicide atrazine is used extensively throughout the Midwest and enters the Mississippi River through surface runoff and groundwater discharge. The purpose of this study was to determine the extent of atrazine contamination in Louisiana's estuaries from Mississippi River water under different flow and nutrient regimes. The results showed that atrazine was consistently present in these systems at low levels.


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According to a report from Environmental Health News, research has shown that atrazine is prone to run off fields and contaminate water supplies. It also drifts hundreds of miles by air from sites where it has been sprayed."

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