Green Eyes On: Another Atrazine Bombshell - Changing Frogs' Sex Traits


Photo via: WikiVisual.
Guest blogger Sara Snow is a green lifestyle expert and board member for Discovery's 24/7 future-forward network Planet Green.

About a year ago the Chief Scientist at The Organic Center (a national organization for which I serve on the Board of Directors), Chuck Benbrook, alerted us to an interesting study being conducted by some UC Berkeley zoologists, led by Tyrone Hayes, looking into the effects of atrazine on frogs. At the time it was concerning enough. Now, the study has been completed and released and the results are astounding! And it might even make you want to puke up your latest meal.

The study has shown that frogs born male can become so completely female that they can actually mate and lay viable eggs. What allows them to make this transformation? Atrazine, which is the second most commonly used herbicide in the world and one of the most toxic. It's also one of the most common man-made chemicals found in U.S. waters.

While atrazine's manufacturer, Syngenta, says that the trace amounts found in water pose no risk to animals or people, a growing body of evidence supports the contrary, showing it to be especially risky to males because of its ability to interfere with the endocrine system, which in turn affects hormone levels. Fish, birds, rats and frogs have shown a feminization when studied (developing female traits and/or body parts) when exposed to levels of atrazine.

But Hayes' frogs have shown the most confirming evidence yet. The males actually became female in everything but their genes. And they were exposed at levels that Syngenta (and the EPA) considers safe.

Hayes and his team took 40 male African Clawed Frogs as tadpoles and put them in water that contained 2.5 parts per billion of atrazine. Water supposedly safe enough to drink. What happened? Ninety percent of the frogs developed low testosterone levels, suppressed mating behavior, reduced sperm production and an overall decrease in fertility.

And then there's the other ten percent. These tadpoles actually developed into "funcationally female" frogs. They mated, laid eggs and those eggs hatched into viable frogs. The one difference was that the new generation of tadpoles weren't a varying mix of males and females. They were all male. Why? Because both parents had contributed only male genes.

My husband (when I read this to him) suggested that it's an undercover scheme by the government to wipe out all females. Maybe...but probably not. What we do know, though, is that we could be drinking and bathing in water with levels of atrazine that are just as high as the frog's water.

Hayes believes that the problem occurs when atrazine is absorbed through the frogs' skin, producing an enzyme that converts testosterone into estrogen and flooding the frog's body with the wrong chemical signals. While the EPA took back their initial concerns with atrazine a few years ago despite concerns by environmental activists, they've begun to reevaluate for potential health threats once again. And that's a very good thing because a completely separate study is now showing a link between atrazine use and obesity levels across the US. The greater the exposure, the higher the weight.

Scary! And just another reason for farmers to farm organically and stay off the junk!

More on frogs:
Amphibians Dethroned as Environmental Canaries
Frogs: The Thin Green Line
Killer Fungus Attacks Rare Frog Species

Tags: Animals