Ento-musings from the University of Kentucky Department of Entomology

Tuesday, March 2, 2010

Atrazine vs. Frogs

by Blake Newton, UK Extension Entomologist

From a news article at CNN: A new study shows that Atrazine can change male frogs to females.

Atrazine is an active ingredient in many commonly-used herbicides. Tens-of-millions of pounds of Atrazine are used in the United States each year, mostly on field crops (like corn). According to the study, it takes only 2.5 parts of Atrazine per billion parts of water to turn male frogs into female frogs. Although this is a new study, it has actually been know for quite a while that Atrazine causes problems for frogs.

But who cares about frogs? Frogs don't help people, right? They don't make any energy for us. They can't operate machinery or edit a document. Not very many people even eat frog-legs anymore. Anyway, you can eat a frog leg whether it's from a male OR a female.

Of course, we care about frogs because they are a part of our ecosystem. Their tadpoles are eaten by aquatic insects, which are then eaten by game-fish and birds. Tadpoles graze on algae, which can take over farm pounds. Frogs also eat lots of insects--and nobody likes those guys! :)

Also, we don't always like to admit it, but people are related to frogs. Not very closely related. But humans are mammals, and mammals evolved from reptiles which evolved from primitive tetrapods--early tetrapods were basically the same thing as amphibians. So people and frogs have a lot in common physiologically. Because of this, scientists are concerned that Atrazine could potentially cause problems to humans, and the EPA has a launched a new investigation to study Atrazine and its effects on human health.

So let's ban Atrazine! Problem solved.

But it's not that easy. Atrazine is a very important herbicide, especially for corn production. It controls weeds very well, and it is relatively inexpensive (and relatively safe to use, and least in the short-term) compared to some of the non-Atrazine options. If Atrazine were banned tomorrow, the economy of corn production would be disrupted, at least temporarily.

Sounds to me like it's a complicated issue with no clear solutions. How come I can't solve any of these problems on this blog???

Visit this PDF from the Minnesota Deparment of Agriculture for a list of many of the brand-name herbicides that contain Atrazine.


  1. Everything is so complicated! Think, Blake! Think!

  2. I once had to answer an essay question that had me proposing a method to figure out why I had been turned into a female overnight. It was for a class in physiology where we were talking about industrial chemical-mediated feminization of frogs.

    It was kind of awkward.

    Apparantly, temperature-regulated sex-determination, like in alligators, is being affected by global warming, too.

    I say the women should invest in parthenogenesis research in order to secure our future as a species! <---sarcasm

  3. Atrazine is used to stop pre- and post-emergence broadleaf and grassy weeds in major crops. Atrazine is the most widely used herbicide in conservation tillage systems, which are designed to prevent soil erosion. 76 million pounds of atrazine were applied in the United States in 2003.

  4. Atrazine is commonly used to kill weeds on highway and railroad right-of-ways or swales. After atrazine is applied, it will remain in the soil for several days to several months.