'Cocktails of contaminants' prove lethal in new study

Leopard Frog and Pesticides iStockPhoto

While canaries are yet to raise the red flag on pesticide exposure, new research from the University of Pittsburgh shows that "ten of the world's most popular pesticides can decimate amphibian populations when mixed together even if the concentration of the individual chemicals are within limits considered safe." 'Decimate', here, is not hyperbole.

Associate professor of biological sciences Rick Relyea exposed gray tree frog and leopard frog tadpoles to small doses of 10 pesticides (insecticides and herbicides… so, agricultural pesticides: the same stuff that's harming the bees. See below) that are used world-wide. Following the pesticide bender—exposure to all 10 chemicals-- 99 percent of the leopard frog tadpoles died.

Back in August, I wrote an article here on PopSci.com about pesticides and bees; in a nutshell, the combination of pesticides that bees pick up outside of their hives is proving to contribute to Colony Collapse Disorder. Although the various pesticides are 'approved' as safe at certain levels, their combinations have not been tested for safety, and bees' plant-hopping pollination habits are generating some toxic chemical cocktails in honey-bee homes.

In Relyea's recent study, Endosulfan-a neurotoxin (which, although it is banned in many parts of the world, is still widely used in US agricultural production) killed 84 percent of the leopard frogs. "Endosulfan appears to be about 1,000-times more lethal to amphibians than other pesticides that we have examined," Relyea said. "Unfortunately, pesticide regulations do not require amphibian testing, so very little is known about endosulfan's impact on amphibians, despite being sprayed in the environment for more than five decades."

Relyea has focused his efforts, over the past nine years, on investigating the connections between the global decline in amphibians, routine pesticide use, and its potentially adverse affects on humans. Amphibians are an environmental indicator species (enter the proverbial canary); their sensitivity to pollutants can hint at what's to come for other types of animals. The pesticides that Relyea used in his study are easily transferred, by wind and water, beyond their initial locations. While the EPA has set guidelines regarding human lifetime exposure to pesticides, testing and limit-setting have neglected to account for the natural processes by which materials move throughout and between ecosystems. Or, say, crop fields. Note to the public: the canary is dead, or at least looking worse for the wear. Amphibians are dropping like bees, and it's time we paid attention and demanded a higher standard of pesticide testing and regulation before it really is too late.

Via:

ScienceDaily.com

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7 Comments

If humanity destroys itself, all remaining species will throw a party the likes of which the world has never seen!

Uh-oh. As soon as CNN/NBC/MSNBC/ABC/BBC gets hold of this "information"
you can count on them using it as further propaganda to make us even more self-loathing as humans.

As it is, we already have people that refuse to bathe in some sort of failed attempt to apologize to the planet. What's next? Will we be feasting on our own feces to "save the rivers?"

When the Earth is done with us, it will shake us off like fleas. Nothing we do good or "bad" is going to prevent the end of civilization. It's going to happen. Big deal.

There's a whole lot of "Chicken Little" going on, and I smell a rat.

evil03mustang you should still care about the environment. Regardless of whether or not "civilization" is going to end... do you want the "last days" of civilization covered in garbage, on a barren wasteland, or would you rather be living on a "decent" planet before the end of days hit? To write off your responsibility to maintain where you live, just cause it's going to get messy again is no way to treat the situation.

I think it's time to stop pumping chemicals into everything. Farming has been done for thousands of years without chems. There are many ways to farm, there are some ancient south american formes of farming that have been proven to be way more productive than the type we do. If we stop using chems it will have an enourmous positive impact on the environment and our health.

SpeedyB - I do a bit of farming on the side (I'm not a farmer, but I have a few acres of garden, orchard, chicken coup, rabits, sheep, etc). I don't sell my produce (other than a few bucks for the extra eggs, but that is only what people choose to give us - we give most of them away).

While my intent is to be cheap (and generous) as possible, none of it is free, and even taking all shipping and profit out of it, I still only do a little better than I could get from the market(except apples and pumpkins, which I drown in annually).

I mention this to illucidate just how cheap food is in the US. Most of it you cannot grow yourself as cheaply even if you have the space and time to spare.

Even as a cottage farmer I still see the very real results of fertilizer and pesticides. They increase production.

Americans have become acustomed to cheap food. This is because farmers super-produce in ways only hybrid fertilizer hungry plants can. While they could produce lower yield varieties that don't strip the earth beneath, this would greatly increase food costs.

We could also chop down all those forset that have grown over farmland since the Great Depression sent them fallow and go back to crop rotation. Of course, the Global Warming crowd would have a fit and food prices would still triple.

You will never convince Americans, who are lucky enough to be in one of the few coutries that produces enough food to geed its population that they should forgoe their prosperity for higher food prices just because of environmental concerns.

Mike Cook

from Kent, WA

People who always wonder why organic foods tend to be more expensive than foods grown with chemical assistance just don't get it. If the Irish had possessed a good field bactericide in 1840 the great potato famine would not have starved so many of my ancestors like miserable rats.

why do we even need pesticides? i mean really who wants an animal or plant chock full of pesticides. personally i don't think we need pesticides all they do is make are food bigger and better while using all these chemicals wich kills animals(our food(hint hint))and our plants then soon once it kills all the animals and the plants it will kill us since we also will be full of growth hormones and pesticieds to kill bugs. why does it cost more or organic food it should cost more to buy food full of pesticides than for something that is healthy and contains no colors or anything. really just grow them naturally cause using these pesticides will one day come back to haunt us.



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