HOME >> BIOLOGY >> NEWS
Popular weed killer demasculinizes frogs, disrupts their sexual development

Berkeley - The nation's top-selling weed killer, atrazine, disrupts the sexual development of frogs at concentrations 30 times lower than levels allowed by the Environmental Protection Agency (EPA), raising concerns about heavy use of the herbicide on corn, soybeans and other crops in the Midwest and around the world.

In an article in the April 16 issue of Proceedings of the National Academy of Sciences, University of California, Berkeley, developmental endocrinologist Tyrone B. Hayes, associate professor of integrative biology, and his colleagues report that atrazine at levels often found in the environment demasculinizes tadpoles and turns them into hermaphrodites - creatures with both male and female sexual characteristics. The herbicide also lowers levels of the male hormone testosterone in sexually mature male frogs by a factor of 10, to levels lower than those in normal female frogs.

As Hayes later discovered, many atrazine-contaminated ponds in the Midwest contain native leopard frogs with the same abnormalities.

"Atrazine-exposed frogs don't have normal reproductive systems," he said. "The males have ovaries in their testes and much smaller vocal organs," which are essential in calling potential mates.

It is unclear whether these abnormalities lead to reduced fertility. Hayes now is trying to determine how the abnormalities affect the frogs' ability to produce offspring.

"The use of atrazine in the environment is basically an uncontrolled experiment - there seems to be no atrazine-free environment," Hayes said. "Because it is so widespread, aquatic environments are at risk."

Because the herbicide has been in use for 40 years in some 80 countries, its effect on sexual development in male frogs could be one of many factors in the global decline of amphibians, he added.

The findings come at a time when the EPA is re-evaluating allowable levels of atrazine in drinking water, which stand today at 3 parts
'"/>

Contact: Robert Sanders
rls@pa.urel.berkeley.edu
510-643-6998
University of California - Berkeley
15-Apr-2002


Page: 1 2 3 4 5

Related biology news :

1. Popular Science announces Third Annual Brilliant 10
2. Popular Science announces second annual Brilliant 10: the countrys top young scientists
3. Popularizing precision agriculture
4. Popular Science outlines need for long-term studies and more regulation in A.R.T.
5. Popular weed killer feminizes native leopard frogs across Midwest
6. Popular weed killer disrupts frogs sexual development
7. Popular pain analgesics found to affect central nervous system: Study identifies both peripheral and CNS mechanisms of action of NSAID use
8. Popular Diet Supplement May Be A Cancer Risk
9. Emu Meat Not A Popular Choice Among Consumers, Study Shows
10. New Studies Shed Light On Facial Features Of Popular Dinosaurs
11. Popular Cure-All Tea Can Cause Toxic Reactions

Post Your Comments:
(Date:6/17/2015)... Deutschland und GERMANTOWN, Maryland , June ... ®   Produktlinie mit DNA-Tests verbessert den ... (NASDAQ: QGEN ; Frankfurt Prime Standard: QIA) hat ... STR-Testkits der Produktlinie Investigator ® ... Markt eingeführt. Die neuen Kits zur Erstellung genetischer Fingerabdrücke ...
(Date:6/16/2015)... , June 16, 2015  With the increasing ... security remains a top concern. The recent compromise of ... the need for strong authentication within government agencies. ... a biometric one-time password (OTP) authenticator, has been submitted ... (FIPS) 140-2 Level 3 validation for tamper proofing. ...
(Date:6/15/2015)... NXT-ID, Inc. (NASDAQ: NXTD ) ("NXT-ID" or the ... commerce market, announces that its leading payment security technology, the ... Experience! @ NYC June 18th. Digital Experience! @ ... in technology to over 300 of the top media covering ... Pavilion in New York City from ...
Breaking Biology News(10 mins):QIAGEN bringt in den USA neue Kits für die forensische DNA-Analyse auf den Markt 2QIAGEN bringt in den USA neue Kits für die forensische DNA-Analyse auf den Markt 3QIAGEN bringt in den USA neue Kits für die forensische DNA-Analyse auf den Markt 4QIAGEN bringt in den USA neue Kits für die forensische DNA-Analyse auf den Markt 5QIAGEN bringt in den USA neue Kits für die forensische DNA-Analyse auf den Markt 6Government Ready Biometric Security Approaching as HYPR Corp. Files FIPS 140-2 Level 3 Validation for Its Proprietary Biometric Token 2Government Ready Biometric Security Approaching as HYPR Corp. Files FIPS 140-2 Level 3 Validation for Its Proprietary Biometric Token 3Wocket Smart Wallet Exhibiting at Pepcom Digital Experience! @ NYC June 18th 2Wocket Smart Wallet Exhibiting at Pepcom Digital Experience! @ NYC June 18th 3
(Date:7/1/2015)... 1, 2015   Decision Resources Group ... of Otezla are its oral administration, alternative mechanism ... by surveyed rheumatologists. Otezla was the first oral ... of active psoriatic arthritis in the ... care includes conventional oral treatments including disease-modifying antirheumatic ...
(Date:7/1/2015)... July 1, 2015  Axovant Sciences Ltd. (NYSE: ... the treatment of dementia, today announced that the ... 22 at 5:45 p.m. EDT following its presentation ... International Conference 2015 (AAIC). The ... , Dr. Lawrence Friedhoff , Chief Development ...
(Date:7/1/2015)... ... July 01, 2015 , ... Apex Therapeutics announced today that company ... Philadelphia, PA. , The presentation took place on Tuesday, June 16 and ... the development of APX3330 for the treatment of pancreatic cancer. A copy of ...
(Date:6/30/2015)... ... June 30, 2015 , ... Students and faculty from ... first half of “Integrative Biotechnology,” an applied biotechnology course team-taught by faculty members ... course combines students from both universities and is taught on both continents. , ...
Breaking Biology Technology:Surveyed Rheumatologists Report That Otezla's Oral Administration is its Single Greatest Advantage Over Currently Available Treatment Options 2Surveyed Rheumatologists Report That Otezla's Oral Administration is its Single Greatest Advantage Over Currently Available Treatment Options 3Axovant Sciences To Host Investor Briefing And Live Webcast During AAIC 2015 Meeting 2Axovant Sciences To Host Investor Briefing And Live Webcast During AAIC 2015 Meeting 3Apex Therapeutics Presented Company Overview at This Year’s BIO International Convention in Philadelphia, PA 2Rivier University and Beijing City University Academic and Cultural Exchanges Begin 2
Cached News: