[Pharmwaste] Frogs exposed to herbicides don't know if they're Arthur or Martha

Mon Jul 16 12:24:17 EDT 2007

Rachel Carson Syndrome Case 4: 
Leopard Frogs and Atrazine Accusations

Tyrone Hayes and Frog Deformities

Finally, there is the research of Dr. Tyrone Hayes, a California
researcher who is the newest media darling in the supposed *global
frog crisis.* Over the past four years, Hayes has been profiled by
National Geographic magazine, Discover magazine, National Public Radio,
and virtually every major newspaper in the country.

Hayes argues that traces of atrazine, one of the most widely used farm
weed killers in North America, are affecting frogs from California to
the Carolinas. The media has run with this theory, placing it at the
heart of all supposed frog ills. As a 2003 editorial in the Baltimore
Sun newspaper stated, *Frogs have been trying to tell us something for
quite a while now. Each spring there seem to be fewer of them, while
increasingly those that do appear are severely deformed; . . . A leading
culprit is believed to be the widely used weed killer atrazine.*35 

Yet Hayes doesn*t argue that atrazine kills frogs or causes
deformities. Instead he says that atrazine feminizes male frogs,
chemically castrating them. Therefore, Hayes argues, atrazine *likely
has a significant impact on amphibian populations* and should be
banned.36 

But even Hayes can*t explain why after 30 years of extensive atrazine
use, frog populations are still thriving in the areas where it is
heavily used. Nor can he provide any field evidence that atrazine has
harmed a single frog species anywhere.

Hayes says research in his laboratory shows that at 0.1 parts per
billion (ppb) atrazine, 36% of males at metamorphosis suffer from
under-developed testes.37 At 25 ppb atrazine, only 12% of males at
metamorphosis have under-developed testes. Hayes says that the greater
effects of atrazine at lower concentrations are not unusual for
endocrine-disrupting chemicals. Yet even Hayes admits that these frogs
were simply delayed in their sexual development and would continue
normal development after metamorphosis. 

Hayes also found 29% of male frogs *displayed varying degrees of
sex-reversal* at 0.1 ppb atrazine, whereas only 8% of males showed
some sex-reversal at 25 ppb atrazine.38 However, scientists from four
universities have been unable to reproduce Hayes*s laboratory results.
Dr. Ronald Kendall at Texas Tech University, a Hayes critic, says,
*validated information should be replicable.*

In response, Hayes accuses the other researchers of outright lying. 

This is a group of individuals whose sole goal is to prove me wrong and
to keep atrazine on the market. Their science is so poor, yet they
continually try to damage or hurt my findings by saying they can*t
reproduce my work under the pretense that they*re doing real science.
I thought only criminals and desperate people lied, not educated people.
My 11-year-old looks over their experiments and sees that they have no
controls. They can*t be that dumb, so they*re lying.39 

These are incredibly strong words for a scientific debate, where
research usually is left to speak for itself and to sort out such
debates. If experimental results cannot be replicated, their validity is
understandably questioned. Instead, Hayes has resorted to ad hominem
attacks, using a word that is almost never used in science debates:
Liar. And Hayes is leveling that charge against an entire group of
researchers from several institutions. 

If the laboratory results are in contentious dispute, what, if
anything, is happening to frogs out in the real world? Even according to
Hayes*s field research, not much.

Hayes conducted field studies in Utah, Wyoming, Nebraska, and Iowa*in
places where atrazine is used regularly and in places where it is
presumably never used. Hayes found traces of atrazine at all but one
location, a wildlife preserve in Iowa. One water testing lab found no
atrazine in the Iowa preserve*s water and another found only trace
levels at the limit of detection.

Bottom line: Hayes could show no correlation between atrazine levels
and *gonadal abnormalities* in northern leopard frogs at any of the
sites. While more than 90 percent of male frogs from one site in Wyoming
had some *gonadal abnormalities,* three other sites with equivalent
atrazine levels had no or low levels of abnormalities. Atrazine levels
were the same in sites in Utah and Wyoming, yet there is approximately a
900 percent difference in the incidence of abnormalities between the
sites. At one Utah site, no abnormalities were seen despite the presence
of the same atrazine levels seen at the high-incidence site in Wyoming.
Moreover, the Iowa site where no atrazine was found had the same
frequency of abnormalities as four other sites where atrazine levels
were both low and high. 

In short, none of the field data makes any sense if atrazine really has
an impact on male frog sexual development. Most damning of all, Hayes
had no trouble finding northern leopard frogs at any of the field sites
he studied. Frogs were abundant at all locations. So much for Hayes*s
claims that atrazine *likely has a significant impact on amphibian
populations.*

Rather than finding an ecological problem in frogs and then searching
for a cause, Hayes seems to have found a laboratory effect from atrazine
and is now searching for an ecological problem.

Finally, Dr. Hayes made a startling statement in a recent paper he
wrote about the lack of scientific evidence that DDT harmed raptor
birds. Dr. Hayes recently wrote that *Years have passed since DDT was
banned in the United States, but it is unclear how much policymakers and
the public have learned from the case of this dangerous pesticide. DDT
was banned on the basis of even less scientific evidence than currently
exists for the negative impacts of atrazine.*40 

Considering the lack of evidence on the *negative impacts of
atrazine,* this says volumes about the DDT paradigm that is currently
driving a sector of the ecological research community and about the
ultra-conservative regulatory stance of the EPA.

http://www.cgfi.org/materials/key_pubs/rachel-carson-syndrome-leapard-frogs-atrazine-accusations.htm

James Bukowski, CIH HEM
Environmental Health Officer
Virginia Tech (1980)

>>> "DeBiasi,Deborah" <dldebiasi at deq.virginia.gov> 7/16/2007 11:36 AM
>>>
http://www.smh.com.au/news/environment/frogs-exposed-to-herbicides-dont-

know-if-theyre-arthur-or-martha/2007/07/14/1183833835538.html#

Frogs exposed to herbicides don't know if they're Arthur or Martha

Study alert: A green tree frog.

Carmel Egan
July 15, 2007

AUSTRALIAN drinking water standards are under scrutiny after
scientific
research linked commonly used herbicides to gender-bending in male
frogs.

The National Health and Medical Research Council has decided to
reassess
its drinking water guidelines after miniscule traces of the herbicides
atrazine and simazine were found to turn the frogs into hermaphrodites
-
creatures with male and female sex organs.

Australian guidelines allow up to 40 parts per billion (ppb) of
atrazine
in drinking water before it is considered a public health risk. But
scientific studies have found male frogs grow ovaries when exposed to
the chemical at the miniscule level of 0.1ppb in water.

"The current Australian Drinking Water Guidelines specify that
atrazine
should not be detected in drinking water, and that if it is detected
remedial action should be taken to stop contamination," said research
council spokesman Nigel Harding.

"The guidelines state that if present in drinking water, atrazine
would
not be a health concern in humans unless the concentration exceeds
40ppb.

"The guidelines are currently under review."

Atrazine, which was banned across the European Union in 2003, has been
used for weed control in Australia for more than 25 years and is the
nation's second most commonly used agriculture chemical agent. It is
sprayed around canola fields, forestry plantations and sugar cane.

There is no legal requirement for atrazine users to notify water
authorities when the chemical is being sprayed.

Dr Tyrone Hayes, an associate professor of integrative biology at the
University of California, presented the findings on the impact of
atrazine on frogs at an address to the Australia Pesticides and
Veterinary Medicines Authority (APVMA), which oversees the continuing
registration of atrazine.

The APVMA's present environmental assessment of atrazine concludes
that
it is "unlikely that atrazine, when used in accordance with the label
recommendations, will contaminate waterways to any extent likely to
present a hazard to the environment, or to human beings through the
consumption of contaminated drinking water".

However, it acknowledges that after storms levels of atrazine in water
will rise and may temporarily exceed the guidelines.

The manufacturer of atrazine, the Swiss corporation Syngenta, rejects
Dr
Hayes's findings.

Deborah L. DeBiasi
Email:   dldebiasi at deq.virginia.gov 
WEB site address:  www.deq.virginia.gov 
Virginia Department of Environmental Quality
Office of Water Permit Programs
Industrial Pretreatment/Toxics Management Program
Mail:          P.O. Box 1105, Richmond, VA  23218 (NEW!)
Location:  629 E. Main Street, Richmond, VA  23219
PH:         804-698-4028
FAX:      804-698-4032

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