Science Current Events | Science News |

New Study Is First to Show That Pesticides Can Induce Morphological Changes in Vertebrate Animals, Says Pitt Researcher

April 03, 2012
PITTSBURGH- The world's most popular weed killer, Roundup®, can cause amphibians to change shape, according to research published today in Ecological Applications.

Rick Relyea, University of Pittsburgh professor of biological sciences in the Kenneth P. Dietrich School of Arts and Sciences and director of Pitt's Pymatuning Laboratory of Ecology, demonstrated that sublethal and environmentally relevant concentrations of Roundup® caused two species of amphibians to alter their morphology. According to Relyea, this is the first study to show that a pesticide can induce morphological changes in a vertebrate animal.

Relyea set up large outdoor water tanks that contained many of the components of natural wetlands. Some tanks contained caged predators, which emit chemicals that naturally induce changes in tadpole morphology (such as larger tails to better escape predators). After adding tadpoles to each tank, he exposed them to a range of Roundup® concentrations. After 3 weeks, the tadpoles were removed from the tanks.

"It was not surprising to see that the smell of predators in the water induced larger tadpole tails," says Relyea. "That is a normal, adaptive response. What shocked us was that the Roundup® induced the same changes. Moreover, the combination of predators and Roundup® caused the tail changes to be twice as large." Because tadpoles alter their body shape to match their environment, having a body shape that does not fit the environment can put the animals at a distinct disadvantage.

Predators cause tadpoles to change shape by altering the stress hormones of tadpoles, says Relyea. The similar shape changes when exposed to Roundup® suggest that Roundup® may interfere with the hormones of tadpoles and potentially many other animals.

"This discovery highlights the fact that pesticides, which are important for crop production and human health, can have unintended consequences for species that are not the pesticide's target," says Relyea. "Herbicides are not designed to affect animals, but we are learning that they can have a wide range of surprising effects by altering how hormones work in the bodies of animals. This is important because amphibians not only serve as a barometer of the ecosystem's health, but also as an indicator of potential dangers to other species in the food chain, including humans."

For two decades, Relyea has studied community ecology, evolution, disease ecology, and ecotoxicology. He has authored more than 80 scientific articles and book chapters and has presented research seminars around the world. For more information about his laboratory, visit

University of Pittsburgh

Related Pesticides Current Events and Pesticides News Articles

Arsenic found in many US red wines, but health risks depend on total diet
A new University of Washington study that tested 65 wines from America's top four wine-producing states -- California, Washington, New York and Oregon -- found all but one have arsenic levels that exceed what's allowed in drinking water.

Chemical exposure linked to rising diabetes, obesity risk
Emerging evidence ties endocrine-disrupting chemical exposure to two of the biggest public health threats facing society - diabetes and obesity, according to the executive summary of an upcoming Scientific Statement issued today by the Endocrine Society.

Root microbiome engineering improves plant growth
Humans have been breeding crops until they're bigger and more nutritious since the early days of agriculture, but genetic manipulation isn't the only way to give plants a boost.

Bumblebees' adaptation to climate change could lead to rise in declining bee population
Rising temperatures in alpine habitats worldwide have resulted in declines in flowering among indigenous plants and contributed to dramatic declines in populations of several bumblebee species prevalent in those regions.

Bush Blitz: The largest Australian nature discovery project finds 4 new bee species
Four new native bee species were recognized as part of the largest Australian nature discovery project, called 'Bush Blitz'.

Women exposed to organic pollutants in early pregnancy have more than 4-times increased risk of gestational diabetes
New research presented at this year's annual meeting of the European Association for the Study of Diabetes in Stockholm shows that a 10-times increased exposure to organic pollutants in early pregnancy is associated with a 4.4 times increased risk of a pregnant woman developing gestational diabetes.

Making pharmaceuticals that degrade before they can contaminate drinking water
In recent years, researchers have realized that many products, including pharmaceuticals, have ended up where they're not supposed to be -- in our drinking water.

Estrogen, shrubbery, and the sex ratio of suburban frogs
Green frogs in the suburbs are seeing a gender revolution.

Water covers 70 percent of the Earth's surface, but only a fraction is fresh
Fresh water--connecting and sustaining all aspects of life on Earth, including food and energy--is in great danger. Moreover, scientists are worried not only about fresh water; they worry that we are not worried enough about fresh water, especially in light of growing concern over recent events, such as the prolonged California drought.

Research could lead to protective probiotics for frogs
In research that could lead to protective probiotics to fight the "chytrid" fungus that has been decimating amphibian populations worldwide, Jenifer Walke, PhD, a postdoctoral researcher at Virginia Tech University, Blacksburg, and her collaborators have grown bacterial species from the skin microbiome of four species of amphibians.
More Pesticides Current Events and Pesticides News Articles

The Myths of Safe Pesticides

The Myths of Safe Pesticides
by André Leu (Author)

The chemical-based conventional agriculture industry claims that the synthesized concoctions they sell as pesticides, herbicides, and insecticides are safe when used as directed, but does the scientific evidence truly support their assertions? Organic agriculturist and lecturer André Leu delves into a wealth of respected scientific journals to present the peer-reviewed evidence that proves the claims of chemical companies and pesticide regulators are not all they seem. Leu translates technical jargon into layman s terms to break down the five most-repeated myths about pesticide safety, refuting them using scientific data. The pesticide industry argues that agriculture, and the global population itself, cannot survive without its products, but Leu warns that we are at risk unless we break...

Pesticides: Chemicals That Kill

Pesticides: Chemicals That Kill
by Choice PH

The Environmental Protection Agency (EPA) claims there is adequate protection from over exposure to toxic pesticides. That claim may be true for the average consumer who carefully washes fruits and vegetables, but it is definitely not true for farm and ranch workers, especially in developing countries.

This eBook examines the various types of pesticides used in our food supply and the possible ill effects of those chemicals to humans and the environment. We discuss the economic impact of using pesticides versus organic farming, and the primary and secondary benefits of pesticide use.

The Pesticide Manual: A World Compendium

The Pesticide Manual: A World Compendium
by C. MacBean (Editor)

The sixteenth edition of The Pesticide Manual provides the most comprehensive information on active ingredients for the control of crop pests in the world. Completely revised and updated, the latest edition contains 1,436 profiles and over 2,600 products, details of 45 additional synthetic molecules and the first approvals under EU 2011 legislation.

The Pesticide Encyclopedia

The Pesticide Encyclopedia
by Kalyani Paranjape (Editor), Vasant Gowariker (Editor), V. N. Krishnamurthy (Editor), Sudha Gowariker (Editor)

In today's world, food security is an important issue. Food shortages push prices up, impacting upon the health and well-being of hundreds of millions of rural poor across the globe. One way to increase food security is to decrease the amount of yield lost to pests. The Pesticide Encyclopedia provides a comprehensive overview of the fight against pests, covering chemical pesticides, biocontrol agents and biopesticides. It also covers interrelated topics such as pesticide toxicity, legislation and regulation, handling, storage and safety aspects, IPM techniques, resistance management, interaction of pesticides with soil and the environment.

An important reference for policy makers, advisers and students and researchers of crop science, this book also includes useful notes on...

Banned: A History of Pesticides and the Science of Toxicology

Banned: A History of Pesticides and the Science of Toxicology
by Frederick Rowe Davis (Author)

Rachel Carson’s eloquent book Silent Spring stands as one of the most important books of the twentieth century and inspired important and long-lasting changes in environmental science and government policy. Frederick Rowe Davis thoughtfully sets Carson’s study in the context of the twentieth century, reconsiders her achievement, and analyzes its legacy in light of toxic chemical use and regulation today.
Davis examines the history of pesticide development alongside the evolution of the science of toxicology and tracks legislation governing exposure to chemicals across the twentieth century. He affirms the brilliance of Carson’s careful scientific interpretations drawing on data from university and government toxicologists. Although Silent Spring instigated legislation that...

Our Daily Poison: From Pesticides to Packaging, How Chemicals Have Contaminated the Food Chain and Are Making Us Sick

Our Daily Poison: From Pesticides to Packaging, How Chemicals Have Contaminated the Food Chain and Are Making Us Sick
by Marie-Monique Robin (Author), Allison Schein (Translator), Lara Vergnaud (Translator)

Over the last thirty years, we have seen an increase in rates of cancer, neurodegenerative disease, reproductive disorders, and diabetes, particularly in developed countries. At the same time, since the end of World War II approximately 100,000 synthetic chemical molecules have invaded our environment—and our food chain. In Our Daily Poison, award-winning journalist and documentary filmmaker Marie-Monique Robin investigates the links between these two concerning trends, revealing how corporate interests and our ignorance about these invisible poisons may be costing us our lives.

The result of a rigorous two-year-long investigation that took Robin across three continents (North America, Europe, and Asia), Our Daily Poison documents the many ways in which we encounter a shocking...

Pesticides In Perspective

Pesticides In Perspective
by William Kucewicz (Author), The American Council on Science and Health (Author)

Year in and year out, agricultural pesticides have been the subject of considerable fear-mongering, leaving the typical consumer with the impression that these chemicals taint much of our food supply and are harmful to human health. In fact, just the opposite is closer to the truth. The published scholarly literature has failed to turn up evidence of adverse human health effects from use of modern pesticides in the real world. Furthermore, in light of the current economic perturbations, as well as the progressive severity of worldwide food shortages and the resulting malnutrition and spiking prices of basic food commodities, the claims that these pesticides pose a threat to human health are false, misleading — and dangerously irresponsible. In Pesticides in Perspective, award-winning...

Pesticide Drift and the Pursuit of Environmental Justice (Food, Health, and the Environment)

Pesticide Drift and the Pursuit of Environmental Justice (Food, Health, and the Environment)
by Jill Lindsey Harrison (Author)

The widespread but virtually invisible problem of pesticide drift -- the airborne movement of agricultural pesticides into residential areas -- has fueled grassroots activism from Maine to Hawaii. Pesticide drift accidents have terrified and sickened many living in the country's most marginalized and vulnerable communities. In this book, Jill Lindsey Harrison considers political conflicts over pesticide drift in California, using them to illuminate the broader problem and its potential solutions. The fact that pesticide pollution and illnesses associated with it disproportionately affect the poor and the powerless raises questions of environmental justice (and...

Pollinator Protection a Bee & Pesticide Handbook

Pollinator Protection a Bee & Pesticide Handbook
by A. Johansen Carl (Author), F. Mayer Daniel (Author), J. Connor Lawrence (Editor)

A handbook designed for use by beekeepers, growers, pesticide applicators, county agents, ag consultants, environmentalists, and research scientists and teachers. The book outlines methods of protecting pollinating bee species to ensure adequate crop pollination. Chapters include: History of Bee Poisoning, Bees and their Relatives, Bee Poisoning Symptoms and Signs, Types of Pesticides, Herbicides, Types of Insecticides, Pesticides Used by Beekeepers, Factors Contributing to Bee Poisoning, Mortality Factors Confused with Poisoning, Food Contamination, Other Contaminant Effects, The Science of Bee Poisoning, Legislation/Regulation, Miscellaneous Poisoning Problems, Reducing Pollinator Damage and Death. There are five Appendixes: Sequential Testing for Bee Hazard, Toxicity of Insecticides...

Critical Thinking About Environmental Issues - Pesticides (hardcover edition)

Critical Thinking About Environmental Issues - Pesticides (hardcover edition)
by Samantha Beres (Author)

Environmental topics pervade classrooms today, but true understanding of them is elusive. All too often, subjects such as global warming, species extinction, and the role of pesticides are reduced to simple slogans because accurate information is hard to find. Yet there is enormous scientific debate about these topics. Thomas Jefferson said that "difference of opinion leads to inquiry, and inquiry to truth." Critical Thinking About Environmental Issues will prepare young people to become inquiring citizens by introducing them to the scientific and economic debates that underlie environmental issues. Each volume will provide readers with a range of scientific views and theories on an environmental topic and introduce facts that are sometimes ignored. Each will help readers use their...

© 2015