A fruit fly walked into a test tube, got coated in carbon black, and lost its ability to climb. Sound like the set up for some bad science-based joke? Nope, it's the premise of a preliminary safety test for carbon nanoparticles.
Nanotechnology—whether multiwalled carbon nanotubes, buckyballs or nanosize particles of silver—has barely begun to make its way into everyday products. But, in an effort to stave off the kind of after-the-fact bad news that has plagued introduced materials ranging from asbestos to bisphenol A (BPA), scientists are preemptively testing the potentially ill effects of the tiny molecules and even atoms engineered at the scale of one billionth of a meter or smaller.
So biologist David Rand of Brown University and his colleague set out to see what impact four types of carbon nanoparticles—buckyballs (fullerene C60), carbon black as well as single-walled and multiwalled carbon nanotubes—had on larval and adult fruit flies (Drosophila melanogaster).
By mixing the different carbon nanoparticles into fruit fly food—small enough to be ingested by larval mouths as tiny as 50 micrometers wide—the scientists delivered a dose of as much as 1,000 micrograms per gram of food without any ill effect on the young insects. Some of the carbon nanoparticles ended up discoloring portions of the subsequent adult flies (see picture), proving it was ingested in quantity but without ill effect, and those adults were able to breed normally in turn.
But carbon black and single-walled nanotubes were not so kind to adult fruit flies exposed in test tubes to layers of the fine nanoparticles in powder form. These quickly engulfed the flies and could not be cleaned off by normal grooming behavior, killing them within six hours. These extrafine nanoparticles also made it impossible for the flies to climb the walls of test tubes—a requisite ability for the average fruit fly—perhaps by blocking or interfering with the foot pads or fluids that enable this feat, the scientists speculate.
Further, flies exposed to lower doses that did not kill them spread the tiny particles to an uncontaminated adjacent test tube, and even to other flies. "Such transport and redeposition may bring nanoparticles into contact with human or environmental receptors that might not otherwise be exposed," the researchers wrote in the upcoming August 15 Environmental Science & Technology. "In these scenarios, we expect nanoparticle–insect adhesion and transport similar to microbial transport by flies [that] act as disease vectors."
It remains unclear what the impact of such human exposure might be, although some studies have suggested breathing some nanoparticles might have health impacts similar to asbestos, which is a carcinogen. If that's the case, beware of flies bearing nanotubes
Saturday, August 8, 2009
Interest in organic food on the rise in China
Unlike most farms in China, no heaps of blackened sewage sludge are piled on the fields at the Green Cow farm. No workers spray pesticides from pumps strapped to their backs. No animals are in quarantine.
An oasis in a Beijing suburb, the organic farm's modest 6 acres boast pepper and tomato plants, fields of corn and wheat, and sunflower patches that pop up in between. Two rotund cows chomp on grasses; under a grove of fruit trees, three young pigs slurp water.
An oasis in a Beijing suburb, the organic farm's modest 6 acres boast pepper and tomato plants, fields of corn and wheat, and sunflower patches that pop up in between. Two rotund cows chomp on grasses; under a grove of fruit trees, three young pigs slurp water.
Restaurateur and environmentalist Lejen Chen started Green Cow with her husband in 2004, fearful of the pesticides, chemical fertilizers and sewage sludge used in the cultivation of most domestic produce.
In China, the organic food movement is growing steadily, led by Chen and a small, dedicated group of like-minded farmers. It's a battle in a country of recurring food scares, loosely enforced regulations and skepticism about paying more for produce that looks the same as regular market fare. But interest in natural food is on the rise.
"The Chinese people are very aware that their food is rubbish," said Romuald Pieters, director of Sustainable Development & Agriculture Creation, a consulting firm operating in China, where the shock of last year's contaminated-milk scandal still stings.
In China, the organic food movement is growing steadily, led by Chen and a small, dedicated group of like-minded farmers. It's a battle in a country of recurring food scares, loosely enforced regulations and skepticism about paying more for produce that looks the same as regular market fare. But interest in natural food is on the rise.
"The Chinese people are very aware that their food is rubbish," said Romuald Pieters, director of Sustainable Development & Agriculture Creation, a consulting firm operating in China, where the shock of last year's contaminated-milk scandal still stings.
Conforming to organic standards when you have no control over neighbors' practices, or what rains down on you, is difficult. But on paper, China's organic farming standards are strict enough, Chen says.
The problem, she says, is making sure that farmers stick to those standards, and ensuring that there are enough authorities to adequately monitor producers who claim their food is organic -- a tall order in a country where toxic, heavy-metal-filled sewage sludge is the cheapest, most easily accessible fertilizer around.
Though one might wonder what could be more organic than excrement, medical waste and factory runoff also make their way into sewer systems. Not limited to China, the use of toxic sludge fertilizer is a widespread problem, seen in the U.S. and elsewhere.
The Chinese Ministry of Agriculture certifies organic products, and its popular "Green Food" label, which designates food produced with restricted amounts of agricultural chemicals, can be seen on products such as fruit, noodles, tea and even beer. The ministry also labels genetically modified food, something the United States does not do.
Though even prosperous locals often pride themselves on thriftiness, in light of recent food scares many are seeking out organic products from suppliers they can trust.
Perhaps the epitome of this mentality is Chen's Community-Supported Agriculture program. Fifteen families receive baskets of fresh seasonal vegetables, and have access to the Green Cow farm, about 20 miles from the center of Beijing, as a leisure spot.
The privilege of a year's involvement with the program costs roughly $45 a week, and families are also expected to help out with chores such as weeding and harvesting at least three times a year. The farm's crops go to program participants, and are also used to supply Chen's New York-style diner nearby.
"It's about proximity and confidence," Pieters said. "You know the person farming, you know how they produce, and you're ready to pay more for these high-quality vegetables."
Chen, who was born in Taiwan to southern Chinese parents and raised in Brooklyn, was not the only one to see a demand for healthy, safe food. Taiwanese entrepreneur Terry Yu runs Lohao City, a successful health-food chain store with seven locations in Beijing and two in Shenzhen.
Yu, a former IT specialist, opened his first shop in 2006, stocking its produce bins exclusively with organic fruit and vegetables from his own ranch. Now Yu has three organic farms around Beijing, which he invites customers to inspect at any time -- an inspiring move in an industry where customer trust is a deciding factor.
"The biggest problem in the Chinese food industry," Yu said, "is that customers don't trust the chain, and the chain doesn't trust its supplier -- no one trusts anyone."
Large-scale supermarkets such as the popular French chain Carrefour suspend informational posters over their organic produce, tracing the vegetables' journey from farm to store. Staff members are stationed alongside to help patrons pick the choicest items and answer any questions.
Chen believes that certifications such as the "Green Food" label are helping foster excitement about eating natural food. Unfortunately, she notes, many still confuse "green," the low-chemical designation, with organic.
Although shoppers' enthusiasm may run high, organic agriculture will need to expand, and become more accessible, before being embraced by the skeptical penny-pincher.
"There's just not enough organic food in China right now" to go around, Chen said. "And people aren't growing it."
The problem, she says, is making sure that farmers stick to those standards, and ensuring that there are enough authorities to adequately monitor producers who claim their food is organic -- a tall order in a country where toxic, heavy-metal-filled sewage sludge is the cheapest, most easily accessible fertilizer around.
Though one might wonder what could be more organic than excrement, medical waste and factory runoff also make their way into sewer systems. Not limited to China, the use of toxic sludge fertilizer is a widespread problem, seen in the U.S. and elsewhere.
The Chinese Ministry of Agriculture certifies organic products, and its popular "Green Food" label, which designates food produced with restricted amounts of agricultural chemicals, can be seen on products such as fruit, noodles, tea and even beer. The ministry also labels genetically modified food, something the United States does not do.
Though even prosperous locals often pride themselves on thriftiness, in light of recent food scares many are seeking out organic products from suppliers they can trust.
Perhaps the epitome of this mentality is Chen's Community-Supported Agriculture program. Fifteen families receive baskets of fresh seasonal vegetables, and have access to the Green Cow farm, about 20 miles from the center of Beijing, as a leisure spot.
The privilege of a year's involvement with the program costs roughly $45 a week, and families are also expected to help out with chores such as weeding and harvesting at least three times a year. The farm's crops go to program participants, and are also used to supply Chen's New York-style diner nearby.
"It's about proximity and confidence," Pieters said. "You know the person farming, you know how they produce, and you're ready to pay more for these high-quality vegetables."
Chen, who was born in Taiwan to southern Chinese parents and raised in Brooklyn, was not the only one to see a demand for healthy, safe food. Taiwanese entrepreneur Terry Yu runs Lohao City, a successful health-food chain store with seven locations in Beijing and two in Shenzhen.
Yu, a former IT specialist, opened his first shop in 2006, stocking its produce bins exclusively with organic fruit and vegetables from his own ranch. Now Yu has three organic farms around Beijing, which he invites customers to inspect at any time -- an inspiring move in an industry where customer trust is a deciding factor.
"The biggest problem in the Chinese food industry," Yu said, "is that customers don't trust the chain, and the chain doesn't trust its supplier -- no one trusts anyone."
Large-scale supermarkets such as the popular French chain Carrefour suspend informational posters over their organic produce, tracing the vegetables' journey from farm to store. Staff members are stationed alongside to help patrons pick the choicest items and answer any questions.
Chen believes that certifications such as the "Green Food" label are helping foster excitement about eating natural food. Unfortunately, she notes, many still confuse "green," the low-chemical designation, with organic.
Although shoppers' enthusiasm may run high, organic agriculture will need to expand, and become more accessible, before being embraced by the skeptical penny-pincher.
"There's just not enough organic food in China right now" to go around, Chen said. "And people aren't growing it."
In-vitro meat: Would lab-burgers be better for us and the planet
A pioneering group of scientists are working to grow real animal protein in the laboratory, which they not only claim is better for animal welfare, but actually healthier, both for people and the planet. It may sound like science fiction, but this technology to create in-vitro meat could be changing global diets within ten years.
"Cultured meat would have a lot of advantages," said Jason Matheny of research group New Harvest. "We could precisely control the amount of fat in meat. We could make ground beef with an ideal fatty acid ratio -- a hamburger that prevents heart attacks instead of causing them."
But it isn't just the possibility of creating designer ground beef with the fat profile of salmon that drives Matheny's work. Meat and livestock farming is also the source of many human diseases, which he claims would be far less common when the product is raised in laboratory conditions.
"We could reduce the risks of diseases like swine flu, avian flu, 'mad cow disease', or contamination from Salmonella," he told CNN. "We could produce meat in sterile conditions that are impossible in conventional animal farms and slaughterhouses. And when we grow only the meat we can eat, it's more efficient. There's no need to grow the whole animal and lose 75 to 95 percent of what we feed it."
Conventional meat production is also hard on the environment. The contribution of livestock to climate change was recently highlighted by the United Nations' report, "Livestock's Long Shadow", while groups such as Greenpeace and Friends of the Earth have demonstrated how soy farming for animal feed contributes to the destruction of the Amazon.
In this context Matheny believes his project could significantly cut the environmental impact of meat production -- using much less water and producing far fewer greenhouse gases.
"We could reduce the environmental footprint of meat, which currently contributes more to global warming than the entire transportation sector," says Matheny.
Preliminary results from a study by Hanna Tuomisto, at the Wildlife Conservation Research Unit, University of Oxford, suggest that cultured meat would reduce the carbon emissions of meat production by more than 80 percent.
Making cultured meat
In-vitro meat is made from samples of animals conventionally slaughtered. For example, "pork" is made from pig ovaries retrieved from slaughterhouses, which are fertilized with pig semen, transforming them into embryos. They are then placed in a nutrient solution, where they grow and develop.
It's a long way from the popular image of animals wandering round the farmyard in the sunshine, but then so is modern intensive farming. The factor that could take the research from the lab to the store and into refrigerators around the world is its remarkable commercial potential.
According to New Harvest, meat is already estimated to be a $1 trillion global market, and demand is expected to double by 2050. With concerns about health, animal welfare and the environment growing the appeal of in vitro meat is obvious.
Watch more
Watch Eco Solutions interview with Jason Matheny, the research scientist for in-vitro meat, and more about meat's impact on the environment on CNN International at 7pm ET on Sunday, August 9.Matheny told CNN that venture capitalists Kleiner Perkins have shown an interest in his technology, while Stegman, a sausage subsidiary of food giant Sara Lee, is a partner. The Netherlands' Government has also invested around $4 million in Dutch research into in-vitro meat production.
But it isn't just the suits who are circling with their checkbooks out -- campaign group People for the Ethical Treatment of Animals (PETA) have announced a $1 million prize for the first commercially viable in vitro chicken product. The Humane Society of the United States has also been supportive.
"We think that a technology to produce cultured ground meats -- burgers, sausages, nuggets, and so forth -- could be commercialized within ten years," said Matheny.
"As with most technologies, successive generations should improve in price, quality, and acceptance. We don't think that matching the taste and texture of ground meats will be very difficult. Both conventional and cultured meat is made of muscle tissue. And conventional ground meat is typically highly processed. Chicken nuggets for instance, are made of something called 'meat slurry' -- it would be hard not to do better!"
Public attitude
But the public doesn't always blindly buy what companies believe they should, and acceptance of what is a very radical proposition certainly isn't a foregone conclusion. There are bound to be claims of "Frankenfoods", and reaction against the work.
"Social acceptance isn't guaranteed, but we all want meat that's safer and healthier," he said. "If cultured meat looks, tastes, and costs the same as regular meat, then I think acceptance will be high. The more we learn about the health and environmental impact of conventional meat, the more cultured meat looks like a good alternative."
One obvious touchstone for how in-vitro-meat will be received by the public is perhaps the way GM crops were -- or were not - accepted around the world, something that Matheny draws encouragement from.
"What's interesting about the GM issue is that it has been controversial in some places, but is a non-issue for most consumers," he said.
"Most Americans are regularly eating GM foods. In any case, it's not necessarily the case that cultured meat would involve GM foods.
"We all want meat that's safer and healthier. If cultured meat looks, tastes, and costs the same as regular meat, then do we care that it's produced in a steel tank, rather than in an animal farm?
"Take hydroponic vegetables. We like the idea that they're produced in sterile water instead of dirt and manure. It's true that in-vitro meat isn't natural. Nor for that matter are hydroponic vegetables, or bread, or cheese, or wine. Raising 10,000 chickens indoors and pumping them full of drugs isn't natural, either, and it isn't healthy or safe. The more we learn about how meat is produced now, the more in-vitro meat looks like a better alternative."
Lab-produced meat also raises some ethical considerations. Kate McMahon, Friends of the Earth Energy and Transport campaigner, believes more attention should be paid to improving livestock conditions rather than developing in-vitro meat.
"At a time when hundreds of small-scale, sustainable farming operations are filing for bankruptcy every day, it is unethical to consider purchasing petri-dish meat. Rather, we should be making it easier and more affordable to raise livestock in a safe, humane and ecologically sensitive manner," she told CNN.
Gillan Madill, Genetics Technologies spokesperson for Freinds of the Earth, thinks that clear perameters for in-vitro development need to put in place: "If we can successfully develop these products, what is the defining line between lab-grown meat and natural animals?" she told CNN.
"That is an especially important question since a high level of differentiation and tissue complexity is required to replicate muscle tissue that we use as meat. We need to draw clear lines in order to prevent the commodification of all life."
Ultimately the success of in-vitro meat may be less about consumer sensibilities and more about the hard realities of feeding a growing global population in a finite world.
"With India and China doubling their meat consumption every decade, there's no sustainable way to satisfy the growing global appetite for meat without a significant improvement in technology," said Matheny.
"Cultured meat offers one solution. Improved plant-based meat substitutes offer another. I expect both will be needed."
Test tube burgers? It seems you could be eating them sooner than you might expect.
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