New discovery could help feed millions (w/Video)

May 27, 2009
NAU discovery could help feed millions
NAU's Loretta Mayer is working on research to speed up fertility in rats to decrease the number of rodents munching on crops intended for humans. Photo by Jerry Foreman, Northern Arizona University

When scientist Loretta Mayer set out to alleviate diseases associated with menopause, she didn't realize her work could lead to addressing world hunger and feeding hundreds of millions of people.

The Northern Arizona University researcher and her colleagues at NAU and the University of Arizona identified a nontoxic chemical technology that when applied to rodents, caused infertility in rats, which feast on crops intended for human consumption.

"This environmentally neutral approach, that has never been available before, will reduce the damage rice-field rats cause in countries that depend on rice as a main food supply," Mayer said.

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A team of NAU researchers is working to increase global food supplies by managing fertility among rice rats. Credit: Northern Arizona University

Rodents consume or damage up to 50 percent of pre-harvest rice crops. Due to the large-scale cultivation of rice worldwide, if rice production were to increase by 10 percent, "this would feed about 380 million people a year," Mayer said. "We can easily increase rice production by 10 percent by reducing rodent fertility in half."

She said this noninvasive approach is more humane than poison, which takes several days to kill rodents and seeps into groundwater, harming other animals and possible food sources.

The sterilization technology derived from Mayer's research, done by Patricia Hoyer and and Glenn Sipes at UofA, investigated potential damage caused to ovarian follicles in women exposed to certain chemicals in industrial settings. Of particular interest was a chemical compound known as 4-vinylcyclohexene diepoxide, or VCD, typically used in manufacturing rubber tires, polyesters and plastics.

She found that low, nontoxic doses of VCD in mice sped the menopausal process and rendered them infertile. She dubbed this new of accelerated menopause "mouseopause."

Mayer and her colleagues have developed a product called ContraPest that incorporates the chemical sterilization treatment into bait. The bait is put into strategically placed stations that lure rodents into cages too small to attract or affect other animals. "No rat or mice I know can resist a little hole," she said.

ContraPest is being tested in Indonesia -- the largest producer of rice in the world, and is currently being registered for rodent-population control in Australia.

"We are testing it in Indonesia, and then our next target site will be in the Philippines. From the Philippines we go to Vietnam," Mayer said.

Scientists adapt the product to different rodent species at SenesTech, the Flagstaff-based company that grew out of Mayer's work on the NAU campus. Named after the word senescence, meaning approaching an advanced age, the young company hopes to create a number of beneficial products.

Mayer and her team of researchers also are adapting the technology platform for population management of other animals. They are formulating a product, ChemSpay, for use in population management of wild animals such as deer, coyotes, foxes, raccoons, horses, buffalo and elk as well as cats and dogs.

"What we are doing right now is we are preparing the translation of this technology to dogs and cats. We have already completed six months of study in dogs. This could have a tremendous impact on reducing the number of animals in shelters," said Mayer noting that not only is the method a cost-effective way to avoid surgical spaying, there's a global impact to canine management most people don't realize.

"Dogs are huge vectors of disease throughout the world," she said. "In India, every two seconds someone is bitten by a dog. The tragedy is that every 30 minutes someone dies from rabies. If you continue to vaccinate against rabies, you won't be able to make a dent. You have to combine rabies vaccinations with fertility control."

She hopes to address rabies problems on the rise in West Africa, India and China.

Australia hopes to put the technology to use in managing its kangaroo, wallaby and camel populations. New Zealand, Spain and the United Kingdom also are in line to put ChemSpay to use.

She said luring students to the research team was easy. "We want them involved with hands-on research and field experience," she said. "The first question I ask interested students is if they have empty passport pages they are ready to fill."

Source: Northern Arizona University

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User comments : 31

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Pointedly
5 / 5 (3) May 27, 2009
How about some "ratopause" for New York City?
ArkavianX
5 / 5 (4) May 27, 2009
About the drop in human fertility, I think it was a British movie, if not, another Hollywood idea already...

Children of Men.

Let's not make that a reality!
daqman
5 / 5 (5) May 27, 2009
I hope this is studied in detail. The thought of putting something in close proximity to the food supply of millions that causes sterility is disturbing. Oops, we just accidentally sterilized the population of Asia....
Photic
4.2 / 5 (5) May 27, 2009
It's non-toxic so it doesn't kill, but renders women sterile.

So mice eat it, what happens to the animals who eat a lot of mice? Then the animal that eats those animals? I just hope the Eco system can take the cut in tasty mice for other animals and that this chemical doesn't reach us.

It comforting to know we're investigating other avenues of wiping ourselves out slowly.
Arikin
3 / 5 (2) May 27, 2009
Isn't kind of ironic that the mice population has grown because we provide large fields of food for them. For rats in large cities we provide tons and tons of garbage all nicely packaged in plastic containers.

But yes we can't do without the large cities and food so we have to do something. Responsibly used this is a humane way to control the problem.

What is a little disturbing is they discovered a way to control fertility while researching ways to "alleviate diseases associated with menopause". Were they trying to speed up the test subjects to the menopause stage?
GrayMouser
5 / 5 (1) May 27, 2009
About the drop in human fertility, I think it was a British movie, if not, another Hollywood idea already...

Children of Men.
Let's not make that a reality!

Or you could read "The Douglas Convolution" by Edward Llewellyn where a contraceptive induces sterility.
GrayMouser
5 / 5 (3) May 27, 2009
It's non-toxic so it doesn't kill, but renders women sterile.

So mice eat it, what happens to the animals who eat a lot of mice? Then the animal that eats those animals? I just hope the Eco system can take the cut in tasty mice for other animals and that this chemical doesn't reach us.

It comforting to know we're investigating other avenues of wiping ourselves out slowly.

That raises some questions:
1) Are the metabolites of this drug biologically active? If so, what is their activity and do they accumulate in the body tissues or environment?
2) Does this drug require long term exposure? If so, can it migrate in to the food chain?
3) What other species does it affect and at what levels? We don't want a 50% reduction in mice to lead to the destruction of an endangered meal worm.
jimbo92107
5 / 5 (2) May 28, 2009
1. How long does VCD persist in the environment? By what process does it break down?
2. Are VCD's effects passed through generations?
3. At very low levels, what are the effects? Is it a mutagen? Teratogen? Carcinogen?
4. Does VCD mimic the effects of any natural hormones?
ThomasS
2.2 / 5 (5) May 28, 2009
im not sure if we need more food. more food = more people = more trouble. Then again, its easy for me to talk, living in the west.
gmurphy
3.3 / 5 (3) May 28, 2009
if evolution has taught us anything, the rats that have the greatest resistance to this infertility treatment will end up dominating the next generation of rodents, who in turn will have an enhanced fertility/ability to resist infertility. So if it doesn't work completely, it won't work at all.
Soylent
3.9 / 5 (7) May 28, 2009
im not sure if we need more food. more food = more people = more trouble.


Don't you malthusians ever get tired of being wrong?

More food means less people working as subsistence farmers which leads to lower fertility rates because it means that basic education becomes affordable and if there's anything that hurts fertility rates it's access to education by women.

Your prefered mode of population reduction(the starvation of ~90% of humanity down to some completely imaginary notion of a carrying capacity based on artificially limiting technology to the bronze age) would lead directly to the deforestation of every square inch of the planet as hungry people fan out and farm anything that can possibly be farmed.
darreng
3 / 5 (2) May 28, 2009
Sounds like very dangerous stuff, worse than a normal poison. If misused could silently do damage to the environment or human populations. The effects might not be found out until years later by which time it would be too late.
Velanarris
3.7 / 5 (3) May 28, 2009
Don't you malthusians ever get tired of being wrong?

More food means less people working as subsistence farmers which leads to lower fertility rates because it means that basic education becomes affordable and if there's anything that hurts fertility rates it's access to education by women.
Quoted so it will be read again. Soylent hit the nail on the head in regards to more food being available.
JayR
not rated yet May 28, 2009
Everyone has great points of concern and counterpoints. Any one of these scenarios or predictions could become a reality. The use of any toxin that has any potential to make its way into the human body should first have a counter-agent (antidote) developed. Regardless of the adjectives that are used to make it sound benign, there is a very real concern that something that was discovered as a toxin in humans is being used in another mammal. Yes, there is minimum infectious dose requirements, nonetheless large scale incorporation of a toxin at the lower end of a food chain is bound to find its way up the chain. I am all in favor of responsible use of scientific research, but just like the scare of Thalidomide we have to remember the lessons of the past, long term research is necessary BEFORE application of a chemical agent outside of a test environment. No amount of modeling can ever compensate for the test of time.
djp
not rated yet May 28, 2009
Whats to say this chemical isn't already being utilized to control human growth. If this chemical can have this effect on all female animals (humans and rodents), shouldn't the first agenda be to halt introduction of this chemical into society?

Just another form of genocide?

How about releasing genetically engineered rodents that would cause infertility to offsprings. Nope, that's too easy.

non-toxic ... hahaha, who are you kidding.

Velanarris
1 / 5 (1) May 28, 2009
Whats to say this chemical isn't already being utilized to control human growth. If this chemical can have this effect on all female animals (humans and rodents), shouldn't the first agenda be to halt introduction of this chemical into society?

Just another form of genocide?

How about releasing genetically engineered rodents that would cause infertility to offsprings. Nope, that's too easy.

non-toxic ... hahaha, who are you kidding.

Governments stand to lose more than they gain by eliminating populations, even rival ones, especially through the introduction of fertility reduction agents.

Eroding the potential tax base and work force isn't in the cards of any government.
Hannibal1
1 / 5 (1) May 28, 2009
Muslim extremists use it on already low fertility Western societies or, alternatively, certain non-Muslim groups who are concerned about the high-fertility of certain extremist prone nations like Pakistan, Yemen and Somalia pursue the plot. Whichever the case, the victim finds out and all Hell breaks loose.


Interesting, when quoting scenarios, Sean W could only come up with situations dealing with Muslims committing terrorist attacks. Since he is in that line of thought, here's another scenario:

The U.S. or Israel decide, regardless of morality, that this stuff should be sprayed on a helpless Muslim population, such as against Iraqis or Palestinians. Considering these two countries recent track records, that seems more likely, now doesn't it?
escherplex
5 / 5 (1) May 28, 2009
The biological effects of VCD have been studied for some time. If you try googling 4-Vinylcyclohexene diepoxide a few things will stand out:

- 4-Vinylcyclohexene diepoxide is produced by epoxidation of 4-vinylcyclohexene with peroxyacetic acid (IARC, 1994) [source]

- Repeated dosing of rats with the ovotoxic chemical, 4-vinylcyclohexene diepoxide (VCD) destroys primordial and primary ovarian follicles via apoptosis (physiological cell death) by accelerating the normal rate of atresia. (Toxicology and Applied Pharmacology, 1999) [mechanism]

- 4-Vinylcyclohexene diepoxide can be absorbed through the skin of rodents. (IARC, 1994) [transdermal]

- induced squamous cell carcinomas of the skin in most males and females. Regarding internally induced neoplasia, both benign and malignant tumors of the ovaries were caused by dermal exposure of 4-VCHD in female mice (toxsci.oxfordjournals.org 2006) [skin carcinoma risk, et al]

- mutagenic in bacteria and caused gene conversion and mitotic crossing-over in Saccharomyces cerevisiae
(IARC, 1994) [potential for long-term pervasive impact]

- This product is not readily biodegradable in a biological wastewater treatment plant and it may be toxic (tedpella.com 1996) [doesn't self-destruct in a timely fashion]

All this suggests that if VCD becomes a common biocide (like DDT) in third world venues then we may be in for some interesting times. [VCD may then be redubbed 'Vaginal Conception Deactivated'. Artificial uterus-es anyone?]
Velanarris
3 / 5 (2) May 29, 2009
All this suggests that if VCD becomes a common biocide (like DDT) in third world venues then we may be in for some interesting times. [VCD may then be redubbed 'Vaginal Conception Deactivated'. Artificial uterus-es anyone?]
I'd rather like to not become Tleilaxu just yet.
Woobie
not rated yet May 30, 2009
- induced squamous cell carcinomas of the skin in most males and females. Regarding internally induced neoplasia, both benign and malignant tumors of the ovaries were caused by dermal exposure of 4-VCHD in female mice (toxsci.oxfordjournals.org 2006) [skin carcinoma risk, et al]

- mutagenic in bacteria and caused gene conversion and mitotic crossing-over in Saccharomyces cerevisiae
(IARC, 1994) [potential for long-term pervasive impact]

- This product is not readily biodegradable in a biological wastewater treatment plant and it may be toxic (tedpella.com 1996) [doesn't self-destruct in a timely fashion]

-From Escherplex

Whoa, you sure can talk some shit, Masked Man. That makes my head hurt. Lets have two steps back on this subject, huh? That's at least 4 major red flags on this compund. Who's going to have the go ahead on applying this stuff? The govts of Indonesia and India?

The most powerful and yet unacknowledged rule of human behavior is the rule of unintended consequences - they will usually be greater than the intended ones.

Soylent
5 / 5 (1) May 31, 2009
We shouldn't repeat history of DDT, which killed some insects - but it stopped the reproduction of carnivorous birds, which resulted into increase of rodent population.


Indeed we shouldn't. Effectively banning DDT for all uses, including combating malaria in the third world is one of the greatest humanitarian disasters in history. It has so far killed tens of millions and dragged down the economies of some of the poorest countries on Earth.

The racist component of this crime shouldn't be forgotten either; the west erradicated their malaria mosquitos with DDT and then pulled up the draw bridges when DDT was no longer needed.

Luckily cooler heads have prevailed and DDT is making a come-back. It is being actively supported by the WHO until better alternatives come along.
Soylent
not rated yet May 31, 2009
(It's also interesting to note that most bird populations grew in the US during the heaviest period of DDT use).
Sirussinder
1 / 5 (1) May 31, 2009
I get it. Her plan is to use technology to kill off and reduce all the other inedible animals in the world and make more room for more humans. Her thinking goes back to the 1950's.
Soylent
not rated yet May 31, 2009
I get it. Her plan is to use technology to kill off and reduce all the other inedible animals in the world and make more room for more humans. Her thinking goes back to the 1950's.


I get it. Your plan is to kill off 90% of humanity so you can try to turn back technology to before the neolithic. Your thinking goes back to 19th century romanticism.
physpuppy
not rated yet May 31, 2009
4-vinylcyclohexene diepoxide, or VCD, typically used in manufacturing rubber tires, polyesters and plastics.




I would be interested in knowing how much of this compound is already in the environment - is there any of it left in the materials after manufacture?



Why I ask is that in products such as many plastics, there are small and possibly significant amounts of plasticizer which eventually leach out. For example, one of current concern is Bisphenol A, and while whether it is a problem of not is still being investigated, many people are concerned about plastics made with it (especially those used with babies) and researchers are concerned if its presence might be affecting their experiments (unrelated to the plasticizer).



escherplex
not rated yet May 31, 2009
@slotin: more likely candidates for that scenario are the pseudoestrogens (such as Bisphenol A) which have been used in the plastics industry for a long time. But that's another potential horror story.
djp
not rated yet Jun 01, 2009
Whats to say this chemical isn't already being utilized to control human growth. If this chemical can have this effect on all female animals (humans and rodents), shouldn't the first agenda be to halt introduction of this chemical into society?

Just another form of genocide?

How about releasing genetically engineered rodents that would cause infertility to offsprings. Nope, that's too easy.

non-toxic ... hahaha, who are you kidding.


Governments stand to lose more than they gain by eliminating populations, even rival ones, especially through the introduction of fertility reduction agents.

Eroding the potential tax base and work force isn't in the cards of any government.


To be honest, this is not about governments. Afterall, the government is composed of the country's constituency. Also, considering that Hitler had a form of government and so did other previous genocides, I fail to see your logic.

What this about is naive scientists giving "expert" opinions as to the possible side effects of such a chemical introduction into the wild. There are better ways to achieve the goals they are trying to achieve; some are far better.
Velanarris
not rated yet Jun 01, 2009
To be honest, this is not about governments. Afterall, the government is composed of the country's constituency.
So the majority of America consists of overweight, white, elderly offspring of liquor bootleggers and other criminal suspects?
superhuman
not rated yet Jun 04, 2009
The biological effects of VCD have been studied for some time. If you try googling 4-Vinylcyclohexene diepoxide a few things will stand out:



- 4-Vinylcyclohexene diepoxide is produced by epoxidation of 4-vinylcyclohexene with peroxyacetic acid (IARC, 1994) [source]



- Repeated dosing of rats with the ovotoxic chemical, 4-vinylcyclohexene diepoxide (VCD) destroys primordial and primary ovarian follicles via apoptosis (physiological cell death) by accelerating the normal rate of atresia. (Toxicology and Applied Pharmacology, 1999) [mechanism]



- 4-Vinylcyclohexene diepoxide can be absorbed through the skin of rodents. (IARC, 1994) [transdermal]



- induced squamous cell carcinomas of the skin in most males and females. Regarding internally induced neoplasia, both benign and malignant tumors of the ovaries were caused by dermal exposure of 4-VCHD in female mice (toxsci.oxfordjournals.org 2006) [skin carcinoma risk, et al]



- mutagenic in bacteria and caused gene conversion and mitotic crossing-over in Saccharomyces cerevisiae

(IARC, 1994) [potential for long-term pervasive impact]



- This product is not readily biodegradable in a biological wastewater treatment plant and it may be toxic (tedpella.com 1996) [doesn't self-destruct in a timely fashion]


This is certainly something we should be very careful about.
superhuman
not rated yet Jun 04, 2009
im not sure if we need more food. more food = more people = more trouble.


Don't you malthusians ever get tired of being wrong?

More food means less people working as subsistence farmers which leads to lower fertility rates because it means that basic education becomes affordable and if there's anything that hurts fertility rates it's access to education by women.


Where is he wrong? More food = more people. Or are you trying to say that more food = less people?

Your prefered mode of population reduction(the starvation of ~90% of humanity...

And where did you get this from?
Velanarris
not rated yet Jun 05, 2009
Where is he wrong? More food = more people. Or are you trying to say that more food = less people?
That's sophistry. More food doesn't necessarily mean more people. Female education is a greater driver of reproduction. More female education = fewer children.

He's saying more food = less farmers, less farmers= less large households operating as subsistence farming steads.