Navigation Links
Early exposure to insecticides gives amphibians higher tolerance later

PITTSBURGH -- Amphibians exposed to insecticides early in lifeeven those not yet hatchedhave a higher tolerance to those same insecticides later in life, according to a recent University of Pittsburgh study.

Published in Evolutionary Applications, the Pitt study found that wood frog populations residing farther from agricultural fields are not very tolerant to a particular type of insecticide, but they can become more tolerant with early exposure.

"This is the first study to show that tadpole tolerance to insecticides can be influenced by exposure to insecticides extremely early on in lifein this case, as early as the embryonic stage," said study principal investigator Rick Relyea, Pitt professor of biological sciences within the Kenneth P. Dietrich School of Arts and Sciences and director of the University's Pymatuning Laboratory of Ecology.

"Amphibian populations are declining worldwide, and pesticides and insecticides are one hypothesized cause," said Jessica Hua, lead author of the paper and a PhD candidate studying biological sciences in Relyea's laboratory. "So this discovery has promising implications for the persistence of amphibian populations."

The Pitt teamwhich also included Nathan Morehouse, Pitt assistant professor of biological sciencesexamined three potential factors that might allow larval wood frogs to have a high tolerance to the insecticide: the concentration of the initial insecticide exposure, the timing of the exposure, and the population's history of exposure. They chose to work with carbaryl, a popular household insecticide that also is used for malaria prevention.

The researchers conducted experiments with both embryos and hatchlings that were collected as newly laid eggs from four Pennsylvania pondstwo near agricultural fields and two farther away. Both embryos and hatchlings from all four environs were first exposed to a low, nonlethal concentration of the insecticide. Later, they exposed the same individuals to a lethal concentration of the insecticide at the tadpole stage and measured the tadpoles' mortality rates over the course of several weeks.

Next, the team wanted to observe whether insecticide tolerance played a role in the frogs' acetylcholinesterase (AChE), a key enzyme in the nervous system of animals. Carbaryl is known to bind itself to this AChE enzyme in frogs, causing their nervous systems to slow. The Pitt team measured the concentration of total tadpole AChE in a sample of tadpole bodies, finding that low exposure levels of carbaryl stimulated the tadpoles to produce greater amounts of the enzymemaking them more tolerant to the insecticide later in life.

The team is now examining whether exposure to an insecticide early in life can make amphibians more tolerant to other insecticides.

"In other words, we are asking if a tolerance to one insecticide can convey cross tolerance to other insecticides that affect the nervous system similarly," said Hua.


Contact: B. Rose Huber
University of Pittsburgh

Related biology news :

1. Antiepileptic drug use while pregnant impacts early child development
2. Early life and in utero factors found to influence testicular function in adulthood
3. Light and nanoprobes detect early signs of infection
4. New data on islet autoantibodies in young children defines early type 1 diabetes development
5. Pearly perfection
6. Herbal extract boosts fruit fly lifespan by nearly 25 percent, UCI study finds
7. NIH awards UCI $10 million to study early-life origins of adolescent mental disorders
8. Early exposure to bisphenol A might damage the enamel of teeth
9. Autism discovery paves way for early blood test and therapeutic options
10. Turning point for early human diets occurred 3.5 million years ago
11. JCI early table of contents for May 24, 2013
Post Your Comments:
(Date:5/24/2016)... , May 24, 2016 Ampronix facilitates superior patient care by providing ...  3D medical LCD display is the latest premium product recently added to the range ... ... ... Sony 3d Imaging- LCD Medical Display- Ampronix News ...
(Date:5/9/2016)... -- Elevay is currently known as the ... high net worth professionals seeking travel for work   ... there is still no substitute for a face-to-face meeting. ... deal with a firm handshake. This is why wealthy ... citizenship via investment programs like those offered by the ...
(Date:4/26/2016)... LONDON , April 26, 2016 ... a product subsidiary of Infosys (NYSE: ... to integrate the Onegini mobile security platform with ... ) The integration will ... to access and transact across channels. Using this ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... June 27, 2016   Ginkgo Bioworks , a ... engineering, was today awarded as one of the ... the world,s most innovative companies. Ginkgo Bioworks is ... the real world in the nutrition, health and ... directly with customers including Fortune 500 companies to ...
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... Researchers at ... most commonly-identified miRNAs in people with peritoneal or pleural mesothelioma. Their findings are the ... read it now. , Diagnostic biomarkers are signposts in the blood, lung fluid ...
(Date:6/23/2016)... , June 23, 2016 /PRNewswire/ - FACIT has ... Ontario biotechnology company, Propellon Therapeutics Inc. ... and commercialization of a portfolio of first-in-class WDR5 ... targets such as WDR5 represent an exciting class ... in precision medicine for cancer patients. Substantial advances ...
(Date:6/23/2016)... SANTA MONICA, Calif. , June 23, 2016  The Prostate Cancer ... to pioneer increasingly precise treatments and faster cures for prostate cancer. Members of ... 77 institutions across 15 countries. Read More About the ... ... ...
Breaking Biology Technology: