Atrazine Turning Frog Princes into Frog Princesses?

Last summer, we wrote a post, Rachel Carson’s Legacy, about troubling chemicals called endrocrine disruptors, potentially harmful to both humans and frogs, that are in herbicides and pesticides, as well as in plastic, cosmetics, and many consumer products. We followed up with a post about Berkeley professor Dr. Tyrone Hayes‘ studies of one endocrine disruptor, Atrazine, a widely-used weed killer, and its effects on frogs. Some of these effects included “intersex” frogs—male frogs that developed with female characteristics.

Recently a new study by Dr. Hayes has brought increased media attention to this issue.  As reported in the article, Weed Killer Creates Mr. Moms (Science News), Atrazine was added to water in the laboratory’s frog tanks in concentrations of 2.5 parts per billion—the same amount that might be found in rivers and streams, downstream of cornfields, golf courses, or domestic lawns, where it is used as a weed killer.

Dr. Hayes and associates found that one-third of the frogs raised in the water with Atrazine behaved like females, even sending out chemicals to attract other males. Out of the  forty frogs he studied, four had high levels of estrogen, and two actually developed female reproductive organs.

The EPA has determined that up to 3 parts per billion of Atrazine are safe in U.S. waterways. But according to Dr. Hayes’s studies, that’s too much. Even minute amounts potentially harm frogs—and humans as well. Endocrine disruptors have been associated with various cancers and reproductive birth defects in boys.

Recently, sixteen cities in six Midwestern states sued the Swiss corporation Syngenta, which manufactures the chemical, for the costs of expensive water filtration systems needed to keep drinking water safe.

Scientists at Syngenta continue to assert that Atrazine is completely safe (despite the fact that it’s been banned in Europe).   When I looked up the topic on google news, I found two Syngenta-sponsored sites with names such as “Atrazine Safe to Wildlife” and “Atrazine and Frogs.” Their website denies the “baseless activist” claims.

As Randall Amster writes in his post, Silent Spring Has Sprung, on Truthout, and reprinted on the Huffington Post, these denials from Syngenta are similar to the backlash Rachel Carson received from chemical companies when she exposed the dangers of DDT in her groundbreaking 1961 book Silent Spring. He writes:

In [Silent Spring], Carson famously argued that the pesticide DDT was responsible for negative impacts on the environment, animals and humans alike, despite disinformation spread by industry and government officials about its purported safety and utility in agribusiness. Silent Spring is often credited with starting the modern environmental movement, yet today we are facing equivalent challenges and similar campaigns to conceal the potential dangers of toxic chemicals in our midst.

Below is a video from the Huffington Post Investigative Fund about atrazine:

See also the New York Times article, “Berkeley Scientist Studies Raise Corporate Hackles.”


A Field of Nightmares? Atrazine, Corn, and Frogs

I’ve always had a sentimental attachment to cornfields—from the magical cornfield in Field of Dreams to the real cornfield across the road from a house I lived in during college years. My mother was born and raised in Iowa and I’m descended from farmers.


But chemicals, in particular Atrazine, used as herbicides on cornfields might be poisoning frogs (and people), and turning fields of dreams into fields of nightmares.  These herbicides run off cornfields into streams and rivers, and leak through the water-treatment process, contaminating groundwater and drinking-water supplies.

Last summer we blogged about the problems of Atrazine. Research by University of California, Berkeley professor  Dr. Tyrone Hayes, for example, has shown the effects this chemical—an endrocrine disruptor—has on frogs. It can cause birth defects and reproductive problems, including such bizarre deformities as male frogs with eggs in their testes. This past week, as reported in the Washington Post, new research at the University of Ottawa found that when exposed to Atrazine fewer tadpoles reached froglet stage. Atrazine appears to affect estrogen in humans as well and has been connected with ferility problems, cancer, and birth defects.

Warning in a Cornfield

Warning in a Cornfield

The EPA, under the Obama administration, has launched a review of the chemical that will continue until fall 2010. It will look closely at Atrazine and other endrocrine disruptors, which might result in tighter restrictions on their use. While this sounds hopeful, Atrazine’s primary manufacturer, Syngenta, has strong ties and influence within the EPA. (Atrazine is banned in Europe, where perhaps industry and government aren’t as closely intertwined as they are in the U.S.).

For more information, please see this PDF,  a report by the Land Stewardship Project and the Pesticide Action Network North America titled The Syngenta Corporation: The Cost to the Land, People, and Democracy.


Frog Scientist: Dr. Tyrone Hayes and Atrazine

In my post Rachel Carson’s Legacy, I wrote about widely-used chemicals called endocrine disruptors that are causing deformities in fish and frogs, and are linked to an increase in genital deformities in newborn baby boys.

When reading about endocrine disruptors, I keep coming across the work of Dr. Tyrone Hayes, a professor in the Department of Integrative Biology, at the University of California–Berkeley. He has studied the effects on frogs of an agricultural pesticide called Atrazine. Hayes found that these chemicals, even at very low levels, were causing male frogs in the wild to develop eggs in their testes (!).

I came across a lecture Dr. Hayes gave called “From ‘Silent Spring’ to Silent Night.” The lecture is about an hour long, but it’s worth watching (see below). Hayes is a funny and engaging speaker and he uses easily understood charts/graphs/pictures to explain how these chemicals effect the frogs—and how they might also effect you.

One Dr. Hayes’s experiments with frogs really hit home with me. He studied two groups of frogs that live along the same river in California. For the experiment he placed the frogs, same species, in cages in the water. One group was placed upstream of the Salinas valley, one of the largest agricultural areas of the country, which is farmed intensely all year round. Runoff containing Atrazine and other chemicals from the farms flows into the river.

The other group of frogs was placed about 50 miles downstream in a clean area. He found that the tadpoles in the area near the farms had retarded growth. They were tiny compared to the frogs in the healthier area. Hayes then injected both groups of frogs with bread yeast. The group of frogs near the farms died within a day or two after being injected with the yeast. The other frogs, from the cleaner area upstream of the agricultural area, survived. They were larger and had stronger immune systems and so were able to fight off the effects of the yeast.

I am not a scientist, but it does make me wonder about claims that some scientists make that the various viruses, parasites, and even the recent claim that frog deformities are caused by dragonfly larvae, are “part of nature.” The frogs living in the “chemical soup” obviously were smaller, weaker, and more susceptible to parasites and diseases.

As Hayes says, we can’t just pass this off as a frog problem that isn’t relevant to humans. Our hormones are chemically identical to frog hormones. Hayes discusses studies indicating higher breast cancer rates in areas where Atrazine is in the well water. He points out that the effects of the chemical may not be obvious now, but may be carried to our children, grandchildren, and even great-grandchildren.

How can you reduce your own exposure to Atrazine? If you live in the Midwest or other agricultural areas, you might consider drinking bottled water or use a Brita filter on tap water, particularly if you are pregnant. The runoff from farms is at its worst from May to August (in the Midwest). As Elizabeth Royte writes in her book Bottlemania: How Water Went on Sale and How We Buy It:

Human kidneys filter Atrazine, and most people don’t spend a lot of time swimming in herbicide-laced water as frogs do. But human fetuses do.

I was surprised to learn that Atrazine is sprayed on Christmas trees as well.

Below are two videos. The first is Hayes’s hour-long lecture “From ‘Silent Spring’ to Silent Night.” Under this video is his “Atrazine Rap,” a 2-minute summary of the lecture in case you don’t have time to watch the longer video.