Popular Weed Killer Feminizes Native Leopard Frogs

October 31, 2002 8:52 AM

Popular Weed Killer Feminizes Native Leopard Frogs Are feminized frogs a canary in the cage? Loss of amphibians in its own right is unacceptable. But are there problems yet unknown higher up the cornbelt food chain?

"Native male leopard frogs throughout the nation's Corn Belt are being feminized by an herbicide, atrazine, used extensively to kill weeds on the country's leading export crops, corn and soybeans, according to a survey conducted by University of California, Berkeley, biologists and reported this week in Nature." [...] "Atrazine has been used on crops since 1956 and currently is the most widely used herbicide in the nation". [...] "Hayes suspects that atrazine boosts the activity of an enzyme, aromatase, that converts male sex hormones, or androgens, to female hormones, or estrogens. The lowered androgens and increased estrogens allow egg cells to grow within the testes, which is normally impossible. Atrazine's effects on aromatase have been demonstrated in fish, reptiles and mammals, but not yet in amphibians.
posted by fred1st (9 comments total)

well it's about time. that damn native leopard frog of mine is sprouting a 'stache and it irritates my sensitive parts.
posted by quonsar at 9:09 AM on October 31, 2002

I grew up in the heart of the corn belt, Nebraska, and one of the most frequent radio ads I remember was for a product called "new Ramrod, with atrazine." I found this very amusing and used to repeat it ala radio voice all the time. Not so funny now.
posted by pejamo at 9:35 AM on October 31, 2002

Every time I run one of our club's displays of local reptile and amphibian wildlife at a local mall, I get the same question: where have the frogs gone? They used to be everywhere around the cottage, kept me up all night; now I don't hear them any more.

Frogs absorb water and nutrients through their skin. You can kill a frog by handling it, if your hands have toxic residues on them. You'd better believe they're canaries.
posted by mcwetboy at 10:06 AM on October 31, 2002

I'm sure this is a double post, but all the same there's a short documentary about this at mediarights' film festival (flash).
posted by djacobs at 10:31 AM on October 31, 2002

I posted a Mefi link on a similar story -- about the possible effects of PCB's and Dioxins on humans a couple of days ago.

Some folks were dubious, and it wasn't a popular post. But there's a large amount of ongoing scientific research into this issue:

Here are a few titles from the National Research Council, under the US Academy of Sciences. The NRC was set up to evaluate areas of scientific research and prepare reports which would serve to guide the decisions of US Gov. policymakers.

These are full length reports, usually by scientific leaders in the fields evaluated, which can be read free online.

Hormonally Active Agents in the Environment

Here is a whole list of related NRC titles:

Related titles
posted by troutfishing at 12:42 PM on October 31, 2002

I believe I heard this reported on NPR a while back, and they said some frogs were actually developing multiple sex organs, sometimes mixed between male/female. This does not strike me as being psychologically or spiritually pleasant for the frog.

I think this is the correct link to NPR, but I can't listen right now, as I'm at work.
posted by Shane at 1:02 PM on October 31, 2002

Reminds me of the morning I fount a tree frog outside my house. Naturally I had to share the find with my wife who was decidedly unimpressed and frightened.

Of course it didn't help matters that the damn frog jumped across the breakfast table and 'stuck' to the side of her coffee cup.
posted by DBAPaul at 4:10 PM on October 31, 2002

Yes, troutfishing, the general indifference on this and similar environmental matters is saddening, a testament perhaps to the pervasive disconnect between most Americans and the natural world and to our feeling that we are above it and can engineer our way out of any potential consequences we have caused to the chemistry or physics of the planet.


Besides, what's a frog done for you lately? And frankly, they are sort of ugly and ikky so why should I care? Right?
posted by fred1st at 2:44 AM on November 1, 2002

fred1st - I was thrilled to find a few frog and toads in my backyard this summer. I like frogs. The are alive, they have their own agendas, they are not of the human world. That is enough.

I was happy to see a few (too few!) -- I though they were all gone.

The "disconnect" you mention is painfull, especially for the most recent research indictating a greater sensitivity of ecosytems to species extinction than had been previously hypothesized -- suggesting a potential (even worldwide) threshold state preceeding nonlinearity.

By the way, are you aware of the new "sudden climate change" research? - see Woods Hole Oceanographic Institute
posted by troutfishing at 9:39 PM on November 2, 2002