Dr.Tyrone B. Hayes* Conducts Research into the Herbicide Atrazine – Part 1

In 1998 Dr. Tyrone B. Hayes* was contacted by the company Novartis/Syngenta to conduct the research into the herbicide Atrazine. His research showed that even low doses as low as 0.1 parts per billion of the herbicide Atrazine can chemically castrate frogs. His work has massive ramifications not only for frog populations, but people as well. Part 1

Needless to say Syngenta were not happy with the results Dr. Tyrone Hayes found and like Rachel Carson, author of Silent Spring in the early 1960’s, Hayes has received criticism from the pesticide industry.

What is Atrazine?

Atrazine is a selective systematic herbicide which provides knockdown and residual action for control of many broad-leafed weeds and some grasses in forestry and agricultural crops. Its use is dominated by the rapid increase in triazine tolerant (TT) canola being grown particularly in Western Australia and Victoria since 1994. Current canola cropping amounts to over 2 million hectares in Australia.

Why use Atrazine?

Atrazine provides efficient, cost-effective weed control and is a component of an inexpensive and effective way to protect crops against many types of weeds. It is the main ingredient in about 40 name-brand herbicides. Because it also can be used as a foundation herbicide, additional herbicides can be applied to control weeds atrazine does not.

Is Atrazine dangerous?

Since the early 1990s the US EPA has reviewed the safety of atrazine 3 times. In each of the two previous reviews the EPA ruled in atrazine’s favor, most recently in 2006 after considering 6,000 studies and 80,000 public comments. However the safe and effective use of atrazine comes with warnings:

  • Follow all label instructions and know when and where to apply the herbicide.
  • Understand both the rate restrictions of atrazine for different soil types and the setbacks from water sources. “Like any chemical, farmers shouldn’t apply atrazine right before a big rain in order to prevent runoff.”
  • Establish 20 metre grass buffer strips along bodies of water and ditches to help filter out atrazine from water flowing across fields,
  • Switch to herbicides that are tank-mixed with atrazine to reduce the amount used,
  • Turn off sprayers when crossing grass waterways
  • Choose crops that don’t require the use of atrazine when planting near water sources.

However atrazine cannot be used in a way that prevents it from contaminating ground, surface and drinking water. Atrazine has commonly been detected in surface and groundwater in Australia. The current Health Value for Atrazine in the Australian Drinking Water Guidelines is 400 times above the amount which Hayes has detected as impacting on the hormones of frogs (and humans).

Why hasn’t Atrazine been banned?
The industry has claimed that Hayes’s results have not been able to be replicated, even though they have.

*Dr Tyrone Hayes is a PhD Professor at the Laboratory for Integrative Studies in Amphibian Biology, Department of Integrative Biology, University of California, Berkeley USA.