Green Living
Dear Community,
Our tech team has launched updates to The Nest today. As a result of these updates, members of the Nest Community will need to change their password in order to continue participating in the community. In addition, The Nest community member's avatars will be replaced with generic default avatars. If you wish to revert to your original avatar, you will need to re-upload it via The Nest.
If you have questions about this, please email help@theknot.com.
Thank you.
Note: This only affects The Nest's community members and will not affect members on The Bump or The Knot.
Our tech team has launched updates to The Nest today. As a result of these updates, members of the Nest Community will need to change their password in order to continue participating in the community. In addition, The Nest community member's avatars will be replaced with generic default avatars. If you wish to revert to your original avatar, you will need to re-upload it via The Nest.
If you have questions about this, please email help@theknot.com.
Thank you.
Note: This only affects The Nest's community members and will not affect members on The Bump or The Knot.
Weed killer can turn male frogs into females
I also posted this on PCE.....but then realized everyone on this board might find this interesting. And terrifying.
Martin MittelstaedtGlobe and Mail UpdatePublished on Monday, Mar. 01, 2010 3:00PM ESTLast updated on Monday, Mar. 01, 2010 7:00PM ESTResearchers in the United States say they have turned male frogs into females by exposing the amphibians to tiny amounts of atrazine, a weed killer widely used on corn fields in Canada and often found in water supplies in agricultural areas.The chemically induced sex change occurred by dosing frogs at concentrations of the herbicide 50 per cent below Health Canada's guideline for drinking water.When the amphibians that had been chemically turned into females copulated with other male frogs that weren't given the herbicide, they laid eggs and all the resulting tadpoles were males.The discovery that in an experimental setting atrazine induces sex changes in frogs is likely to further increase the controversy over the chemical, which has been banned in Europe because it contaminates ground water but is one of the most commonly used herbicides in North America.The finding was based on a study led by researchers at the University of California Berkeley and released today online in the Proceedings of the National Academy of Sciences, a major peer-reviewed U.S. journal. The study concluded that the males had been ?chemically castrated? and ?completely feminized.??There is no question that atrazine completely sex-reversed genetic [chromosome] males, resulting in reproductively functional females,? it said.The lead researcher, Tyrone Hayes, a professor of developmental endocrinology at the university, said the possibility that a herbicide can skew reproduction in frogs represents a potential new threat to the amphibians, whose populations are dwindling in many parts of the world.?Everybody is focusing on things that kill frogs in terms of global amphibian decline, but you can easily imagine a population going extinct just because they don't breed properly,? Dr. Hayes said.All the atrazine sold in Canada is made by Syngenta AG, a Swiss-based seed and pesticide producer that has previously disputed findings that the herbicide hazardous. ?We stand behind the safety of our product,? said Judy Shaw, a company spokesperson.She said Syngenta hasn't seen the latest research and isn't yet in a position to comment on it.Atrazine has been dogged by controversy since the late 1980s, when it was found to cause mammary tumours in one strain of laboratory rats, a discovery followed by contested research indicating it may have gender bending impacts on amphibians and other types of animals.The U.S. Environmental Protection Agency is currently re-evaluating the safety of the weed killer based on concerns it is polluting groundwater and may be a human health hazard. But in 2007 it rejected the view that the chemical can alter the sexual development of amphibians, in part because research hasn't consistently detected these effects.Health Canada also conducted a review of atrazine released in 2007 that concluded the chemical doesn't ?entail an unacceptable risk to the environment.?But it is looking at the new research. ?Health Canada is monitoring new findings on atrazine and will take additional regulatory action if necessary to protect human health and the environment,? it said in a response to the study.Regulators typically don't react immediately to new studies until their effects are confirmed by other scientists, which would give the results added weight.Some researchers are skeptical about the sex change finding. The study speculated atrazine causes frogs to increase the amount of a key enzyme known as aromatase, that converts testosterone to estrogen.?That theory doesn't stand up to closer examination,? contends Keith Solomon, a professor of environmental biology at the University of Guelph. He said that previous testing hasn't found aromatase increases ?in well-conducted laboratory studies.?In the new study, the researchers exposed a group of male African clawed frogs, a commonly used laboratory species, to 2.5 parts per billion of atrazine from hatching onward, and another male group to none of the chemical.Of the 40 exposed male frogs, four were turned into females, four were normal males, and the rest were emasculated, with decreased testosterone levels, feminized larynxes, and decreased sperm production. None of the so-called control animals experienced gender changing impacts.
A part per billion is an extremely small amount, the equivalent of one second or elapsed time over a 32-year period. The experimental dose used was below Canada's drinking water guideline of 5 ppb, but above the safe wildlife exposure standard of 1.8 ppb. Figures contained in Health Canada's 2007 atrazine evaluation found concentrations in groundwater of up to 1.2 ppb.
Warning
No formatter is installed for the format bbhtml
Re: Weed killer can turn male frogs into females
Atrazine is nasty stuff, but is still not considered to be one of the more dangerous(!). It often shows up in groundwater and drinking water. It is also one of the most widely used agricultural chemicals. Here are some more sources of information about it (and resources for other chemicals):
MSDS Sheet:
http://www2.hazard.com/msds/mf/cards/file/0099.html
Union of Concerned Scientists:
http://www.ucsusa.org/scientific_integrity/abuses_of_science/atrazine-and-health.html
Agency for Toxics Substances & Disease Registry:
http://www.atsdr.cdc.gov/toxprofiles/tp153-c1-b.pdf
Best sound ever: baby's heartbeat! (Heard @ 10w1d)
A lot of endocrine disruptors end up in our water supplies and have been doing crazy stuff to amphibians and fish as far as gender. Scary stuff! Obviously there are some implications as far as what it is also doing to us, but more so, WTF are we doing to our planet? I don't mean to sound all tree-huggy, but seriously, WTF? What if we really screw up an entire segment of our ecosystem?
And the thing is, NONE of this stuff is actually necessary. None of it! If it was all from a drug that cured cancer, well, that'd be something we'd have to figure out how to try to minimize and contain, but this is all stuff like weed killers and additives to plastics and air fresheners.
Thats what makes me really angry....is that its not as if this stuff is required to grow corn. Yes, certainly it helps farmers get a higher yield, but at a devastating cost to the environment and a society as a whole.
I was still buying regular cereals, bread etc till this morning (previously I bought organic milk, meat, fruits, veggies, but regular canned stuff). It makes me sick to think that Corn-Flakes are basically poisoning people.
Yeah that's true unfortunately. They're also made out of genetically modified corn.
All these chemicals are designed to make the American industrial farmer's life easier. He doesn't have to weed, or cultivate, or pay attention to the quality of the soil. He just sprays herbicides, pesticides, and fertilizers. Problem solved! The reason why organic food is more expensive is that it's more labor-intensive. Organic farmers have to weed, and deal with pests without chemicals, and enrich their soil without fertilizer. Industrial farmers can spend as little as 60 days a year actually working with their crops while organic famers spend 4 times that or more.
When I went to the public meeting for Roundup (another weedkiller) Ready Alfalfa, the farmers went on and on about how the crop increases their yields and reduces weeds. But at what cost? Contamination of our groundwater, and poisoning other plants and animals. The farmers say they can't control weeds in their crops. Well I think the bigger issue is you have too many acres of the same crop.
Exactly! And they -- mostly big Ag -- profit off methods that end up costing us more in the long run. So instead of paying .10 more per egg, people want cheap eggs, but then the eggeries (I made that word up...I think) pollute the ground and waterways, and then decimate shellfish and fish we eat and drive up the costs, and then we have to clean that up, with taxpayer money. We want cheap corn and cheap beef, but again, the pollution from it chokes the life from waterways, and then what about all the scarier possibilities? What about when we realize how bad endocrine receptors are? They're in so much. Do we really think those who profited from it will be the ones to pay for cleanup? Who paid for -- and IS paying for - the cleanup of PCBs? Certainly not the companies who profited from their use. No, the taxpayers, us.
Cheap food is NOT cheap in the longrun!