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The Best Science Writing Online 2012
Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way...
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Talk about milking an issue. Adding a new twist to the debate over the safety of hormones in milk, a new industry study concludes that injecting cows with a growth hormone known as recombinant bovine somatotropin (rbST) designed to increase their milk production is environmentally friendly. Why? Because it has the potential of reducing the number of greenhouse gas–emitting dairy cows on the planet without decreasing milk production.
"By using rbST, we could produce more or the same amount of milk with fewer cows," says animal nutritionist Judith Capper of Cornell University, co-author of the study published in Proceedings of the National Academy of Sciences USA. "That means less land use, feedstock, nutrients, greenhouse gases, excretion—all positive effects on the environment."
The National Research Council in Washington, D.C., estimates that dairy cows account for as much as 20 percent of human-induced emissions of methane, a potent climate change–causing greenhouse gas.
According to the new study, if U.S. farmers injected their dairy cows with bovine growth hormone, it would take just 843,000 cows to produce the same amount of milk as one million untreated animals, potentially saving 2.3 million metric tons of feed—and therefore 540,000 acres (219,000 hectares) of cropland—as well as reducing the global warming impact by the equivalent of 400,000 cars. Researchers say the treatment would up the milk output of cows by nearly 7 percent, potentially decreasing emissions by about the same amount annually.
Some scientists and consumer advocates, however, are skeptical. The study was conducted with a scientist, Roger Cady, who is also the rbST technical project manager for Monsanto, the Saint Louis–based agricultural giant that manufactures and markets it under the brand name POSILAC. In addition, the lead scientist, nutritional biochemist Dale Bauman of Cornell University, has been a paid consultant for Monsanto since the 1980s, though he declined to disclose how much the company has paid him over the years. He insists that Monsanto did not influence his decision to spend as much as $10,000 in university funds for this study.
There is currently a debate raging over the safety of bovine growth hormone. The U.S. Food and Drug Administration (FDA) in 1993 ruled that it was not harmful and could be injected into cows to improve their milk production. But some studies have linked it with a risk of mastitis (udder infection) in cows, requiring the use of antibiotics that may in turn be contributing to the evolving resistance of bacteria to the drugs.
Bovine growth hormone is also known to stimulate the production of insulinlike growth factor 1 (IGF1) by the liver; some studies have shown that high levels of IGF1 in the bloodstream may heighten the risk of prostate and breast cancers as well as a woman's chance of conceiving twins. As a result of consumer concerns, farmers in Australia, Canada, the European Union and New Zealand do not inject their cows with bovine growth hormone.
Monsanto is currently in the midst of a fight in the U.S. to prevent dairy farmers from labeling their milk as rbST-free or as produced by cows not treated with bovine growth hormone. The company charges that such claims cannot be verified, because there is no inexpensive test to prove that cow milk is free of artificial hormones. At Monsanto's request, several states are weighing new regulations barring such labeling, even though the FDA last year ruled that such labels are neither false or misleading.
Many U.S. dairy farmers have pledged not to use the growth hormone in their products, and corporate milk consumers such as Kraft Foods and retailers such as Wal-Mart have announced plans to shift to dairy products that do not contain artificial hormones.
In addition to conflict-of-interest concerns, critics of the study charge that it was based on a faulty premise. "It all hinges on one notion: that there is an increase in feed efficiency," says biologist Michael Hansen of the Consumers Union, an advocacy group that is leading the fight for labeling and against use of bovine growth hormone. In other words, the study assumes that POSILAC increases the ability of individual cows to produce more milk from the same amount of feed, despite an FDA ruling to the contrary. "If the basic assumption is wrong," Hansen says, "then everything that flows from it is of questionable status."
He notes that the FDA analyzed the environmental impact of POSILAC some 15 years ago (as it assessed its safety) and at that time concluded that it might actually increase greenhouse emissions slightly because of, among other factors, the diesel expended to transport it to farms. But any increase or reduction, the agency said, would be "extremely small and insignificant compared to total worldwide emissions of carbon dioxide and methane."
The National Academy of Sciences and the U.S. Environmental Protection Agency have reached similar conclusions about the potential environmental benefits of bovine growth hormone use, but Bauman—who dismisses charges that his relationship with Monsanto taints the study's findings—says his research was more "rigorous" and detailed.
Dairy farmers, however, have already done a pretty good job of reducing greenhouse gas emissions without resorting to bovine growth hormone: Such emissions from the U.S.'s roughly nine million cows are 70 percent lower than those from a dairy herd of 25 million in the 1940s, thanks to improvements in breeding and nutrition, according to U.S. government statistics. And researchers at the University of Melbourne in Australia say they can be cut by another 50 percent simply by changing cow feed to include more digestible grasses, thereby reducing the methane output.
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11 Comments
Add CommentAs a matter of fact, a partial replacement of animal proteins by vegetables ones in our daily diet, apart from ethical arguments not relevant in a scientific reasoning, would allow a substantial energy saving, such that the thesis of this article would turn out to be of no interest at least for the size of the greenhouse emissions involved. And how about the benefits for our health? I am not a vegetarian, only a citizen weary of ridiculous debates and alleged findings whose concealed aim is delaying any serious approach to the epoch-making drama we are light- heatedly going to put up with.
Reply | Report Abuse | Link to thisI can't believe you would post an article about the same company whose sends people to sue farmers if they don't rebuy their for-profit GM seeds. GM seed pollen is what is causing bee colony collapse. Research the new studies from Indiana University on it which PROVES GM Round UP ready corn pollen kills cadisflies in nearby streams AND about Germany ready to BAN similar seeds by Bayer FOR causing bee colony collapse.
Reply | Report Abuse | Link to thisOur forefathers did okay BEFORE all the chemical additives in our food system.
BUY locally organic. STOP MONSNATO!
Check out Organic Consumers on the net.
Here is the link to Millions Against Monsanto:
Reply | Report Abuse | Link to thisSign up for their emails. Learn about organic living.
Save a cow.
http://salsa.democracyinaction.org/o/642/petition.jsp?petition_KEY=1265
And start a victory garden in your back yard to combat high food prices....it's a fun family thing to do.
Reply | Report Abuse | Link to thisLetter to the Editor: The article by David Biello titled “Can Bovine Growth Hormone Help Slow Global Warming” relates to a publication that originated from my research group (http://www.pnas.org/content/105/28/9668.full.pdf+html). Firstly, the article suggests that our conclusions regarding the environmental benefits of rbST maybe incorrect. The environmental benefits of rbST use have been documented in previous scientific studies referenced in our manuscript. Likewise, the National Research Council/National Academy of Sciences, Environmental Protection Agency, Council for Agricultural Science and Technology, US Congress Office of Technology Assessment, and the Executive Branch of the Federal Government have all published reports that conclude the use of rbST mitigates the environmental impact of dairy production. The originality and scientific basis of our research is three-fold. Firstly, all data and calculations are referenced to peer-reviewed scientific or governmental publications. Secondly, our model uses the NRC Nutrient Requirements of Dairy Cattle (the nutritional gold standard for the dairy industry), as the platform to calculate dairy herd nutrient utilization and waste outputs. Finally, our model uses a life cycle assessment approach to quantify the environmental impact of rbST use.
Reply | Report Abuse | Link to thisSecondly, the article quotes a series of erroneous statements by Michael Hansen that are based on his failure to understand animal agriculture and the concept of productive efficiency even though this is discussed and referenced in our publication. The quality of nutrients required to maintain the cow and to synthesize each unit of milk is not altered by rbST use. However, rbST allows each cow to eat more feed and use all of the extra feed nutrients to synthesize more milk. Thus, fewer animals are needed to produce a given amount of milk, which means less feed is needed to maintain the population. The resulting improvement in productive efficiency (milk output per feed resource input) reduces total animal waste production and requirements for feedstuffs and cropland. While it is true that productive efficiency represents the basis for most advances in animal agriculture and any technology or management practice that improves productive efficiency will also mitigate environmental impact, these effects are additive and rbST is the only technology that has the potential to singly reduce environmental impact by 9%.
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Reply | Report Abuse | Link to thisThirdly, the article raises the issue of food safety concerns about rbST without adequate background context. Food safety is an important issue and the FDA doesn’t approve a technology until it has been proven safe. However, one can always find individuals or special interest groups that will raise doubts about the safety of a particular food or technology, and these are the sources referred to in the article. As one of the first products of biotechnology, the safety of rbST has been extensively evaluated. To date, regulatory agencies in more than 50 countries have confirmed that use of rbST is safe and does not threaten human health. In addition, more than 20 of the most prestigious medical associations and scientific societies in the world, including National Institute of Health, American Medical Association, American Cancer Association, and WHO/FAO have conducted independent assessments and reached a similar conclusion. Some countries that have approved the human safety of rbST do not allow its commercial use by dairy producers, e.g. Canada and European Union, but even in these countries dairy products from rbST supplemented cows may be imported and marketed without restriction or special labeling. There are issues where knowledgeable scientists disagree, but the safety of milk produced by rbST-supplemented cows is not one of them.
Dale E. Bauman
Liberty Hyde Bailey Professor
Cornell University
How many of you actually live on a farm? Or have had first had experience on a farm? So many people in our government never have, and, like many of you, are trying to decide what happens for us in the agricultural world. The fact is, ALL milk has BST in it. You can NOT remove it. Take a sample of milk from a rBST injected cow, and a sample from a cow raised on 'organic' standards, test each milk sample 1,000 times, and you will never find a difference between them, ever. The fact that Wal-Mart has banned all milk with BST in it is ludicrous and ignorant, they were not informed of the facts.
Reply | Report Abuse | Link to thisHow many of you actually live on a farm? Or have had first had experience on a farm? So many people in our government never have, and, like many of you, are trying to decide what happens for us in the agricultural world. The fact is, ALL milk has BST in it. You can NOT remove it. Take a sample of milk from a rBST injected cow, and a sample from a cow raised on 'organic' standards, test each milk sample 1,000 times, and you will never find a difference between them, ever. The fact that Wal-Mart has banned all milk with BST in it is ludicrous and ignorant, they were not informed of the facts.
Reply | Report Abuse | Link to thisRBST might not have any negative effect on humans. But it has very negative effects on cows. Cows injected with rBST have higher rates of mastitis, lameness and fertility problems which all contribute to higher culling rates. That means farmers using rBST have to replace their cows more frequently. And there goes any of the claims that using rBST reduces the number of cows we need. The aforementioned study fails to mention that. I have read this study - all they did was recalculate figures taken from other studies. Their findings seem very hypothetical!
Reply | Report Abuse | Link to thisRBST might not have any negative effect on humans. But it has very negative effects on cows. Cows injected with rBST have higher rates of mastitis, lameness and fertility problems which all contribute to higher culling rates. That means farmers using rBST have to replace their cows more frequently. And there goes any of the claims that using rBST reduces the number of cows we need. The aforementioned study fails to mention that. I have read this study - all they did was recalculate figures taken from other studies. Their findings seem very hypothetical!
Reply | Report Abuse | Link to thisRBST might not have any negative effects on humans, but it has very negative effects on cows. Cows injected with rBST have much higher rates of mastitis, fertility problems and lameness which leads to higher culling rates. Therefore, farmers have to replace their cows more frequently. Their goes any claims of lower environmental impacts from rBST. I read the study above. All they did was take figures from other studies and recalculate it. And they models they use and their findings seem very hypothetical.
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