--- In [EMAIL PROTECTED], "Shukrainternationals" 
<[EMAIL PROTECTED]> wrote:
> Where did you get this report?
> I could not open the site: http://story.news.yahoo.com/news?
> Can you open and post the details?
> Thanks


>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Weedkiller Makes Male Frogs Into Females-Study 
Mon Apr 15, 5:34 PM ET 
By Maggie Fox, Health and Science Correspondent 

WASHINGTON (Reuters) - The most popular weedkiller in the United 
States can give male frogs female sex organs and other attributes, 
researchers said on Monday, in a study that could shed light on the 
global decline in amphibian populations. 

  
Very low levels of the herbicide atrazine can cause male frogs to 
grow female sex organs and curtail their croaks -- key to attracting 
mates in the frog world -- a team at the University of California 
Berkeley found. 

The frogs appear normal on the outside, but often have both male and 
female sex organs, the researchers said, adding that the findings may 
help explain the amphibian population decline. 

The decline worries scientists because amphibians such as frogs 
respond to environmental dangers before other species. 

"Atrazine is the most commonly used herbicide in the U.S. and 
probably the world," the researchers wrote in their report, published 
in the Proceedings of the National Academy of Sciences (news - web 
sites). "It can be present at several parts per million in 
agricultural runoff and can reach 40 parts per billion in 
precipitation." 

Such a common pollutant would reach many animals as well as humans, 
so the team, led by Tyrone Hayes, tested its effects on the African 
clawed frog Xenopus laevis. 

They put tadpoles into water laced with levels of atrazine much lower 
than allowed by the U.S. Environmental Protection Agency (news - web 
sites), and found that the weedkiller had serious effects on 16 
percent of them. 

These genetically male frogs had testicles and ovaries, and many had 
testicles that did not function properly and contained eggs and 
sperm. Their levels of testosterone were much lower than normal. 

The male frogs also had much smaller larynxes than normal, which 
could affect their ability to croak and attract mates, Hayes' team 
reported. 

The researchers determined that atrazine is an endocrine disruptor -- 
a class of chemicals that disrupts the hormones in the body. Many 
pesticides fall into this category and it is one of the qualities 
that can make them dangerous. 

"We hypothesize that atrazine ... promotes the conversion of 
testosterone to estrogen," they wrote. 

"This widespread compound and other environmental endocrine 
disruptors may be a factor in global amphibian declines." 

Environmentalists responded with alarm. 

"This research is further proof that this pesticide is a major threat 
to public health and the environment," the Natural Resources Defense 
Council said in a statement. 

"EPA's tap water standard for atrazine is 3 parts per billion -- 30 
times higher than the level at which these dramatic sexual side 
effects occurred. At higher levels, the frogs developed additional 
health problems," it added. 

"This rigorous scientific study reinforces what we and other 
scientists have been saying for years -- atrazine is a dangerous 
pesticide," the council's Jennifer Sass said. "It's no surprise that 
it's been banned by many European countries." 

She said the study had implications for humans, especially children 
who have not reached puberty. 

http://story.news.yahoo.com/news?
tmpl=story&u=/nm/20020415/sc_nm/environment_frogs_dc_1


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