The Safety of rBST

Published on Fri, 12/11/2009 - 12:25pm

Elanco Animal Health hopes thousands of studies - and the need to feed the world - will help Posilac make a comeback.
That’s the trade name for the recombinant Bovine Somatotropin (rBST) product marketed in the United States for the last 16 years, 15 of them by Monsanto. A flurry of bad publicity caused many retailers, supermarket chains, and ultimately bottlers and cooperatives to reject milk from cows treated with the hormone; in August 2008, Monsanto sold the product—both its assets and liabilities—to Elanco parent company Eli Lilly for $300 million.

There have been critics all along. A group of dairy farmers in Wisconsin, for instance, got enough signatures to force an eventually unsuccessful vote to repeal the dairy research and promotion check off in 1993. That was the year the FDA approved rBST, and the farmers were incensed that their check off dollars had been used to promote the technology. But Posilac remained a part of the animal health regime of about 30% of the U.S. cowherd for more than a decade thereafter. It increases milk production per cow by about 10 lbs. per day, and there was little organized opposition to its use.
The first cracks appeared in 2006, when two leading dairies that service New England began marketing their milk as “rBST free”. They were really trying to capitalize on the popularity of organic milk, which had seen demand growth of 20% a year for several years; the dairies sold the milk produced without rBST at a premium to conventional milk, but cheaper than organic.
But within months, retail chains like Safeway and upscale eateries like Starbucks were demanding that their suppliers deliver milk produced without rBST. Leading coops began requiring their members to sign statements that they would not use the product in their herds. Monsanto tried to stem the tide by enlisting farmers to promote Posilac’s positive attributes, but less than two years later, the product was on the block, and Elanco snapped it up.
Elanco spokesman Dennis Erpelding says rBST is part of the answer to the needs of a hungry world. “If you look at recent FAO numbers,” he says, “they state over the next 40-50 years, due to population growth and just improved diets, we’re going to need to double our food production capabilities. And when you look at limited land and limited resources, technological innovation is going to be a key part of that.”
Erpelding says once Elanco took possession of Posilac, they quickly realized few people were familiar with the human and bovine safety tests that had been conducted on it over the years.   “What we’ve done is looked at work with the total dairy food chain, re-educating them with that,” he says. They’ve also conducted market research, and come to the conclusion consumers want food that is both affordable and sustainable; those are the advantages, the company says, Posilac brings to consumers.
But the concerns about the product’s safety prompted Elanco to hire an international team of university scientists, who analyzed and summarized the staggering amount of safety data—90,000 scientific publications, they said—on rBST. Their report, Recombinant Bovine Somatotropin (rBST): A Safety Assessment, was presented to a joint meeting of the American Dairy Science Association, the Canadian Society of Animal Science and the American Society of Animal Science in Montreal, Quebec on July 14, 2009.
The head of the panel was former USDA Undersecretary for Food Safety Richard Raymond. Now living in Colorado, Raymond says he’s a “part-time consultant, part-time retired…I agreed to sign on as a consultant with Elanco for all food safety issues that might come up, and this just happened to be the first project that they asked me to chair.” Elanco compensated all of the scientists who participated in the project. Raymond, a medical doctor, says members of the panel “had a great deal of expertise in their given areas…the depth, and perhaps the knowledge, on that panel is really amazing.”
The paper states no “scientifically documented detrimental effects on human health” from rBST have been identified. It addresses numerous claims by the hormone’s detractors, the most significant of which—the one that prompted many of the industry’s customers to close their doors over the last three years—relates to Insulin-like Growth Factor, or IGF-1. Consumer activists say milk from treated cows has increased levels of IGF-1, which has been tied to an elevated risk of cancer.   The paper acknowledges a “slight increase in the amount of IGF-1 in the milk,” but maintains it’s less than the normal amount of variation of IGF-1 in milk from different animals, and is “very minor” compared to the amount secreted daily by the human body.
It was one of several differences between treated and untreated cows that the paper dismisses as insignificant. Another concern raised by consumer advocates is that treated cows produce milk with higher somatic cell counts, a sign of infection; the scientists agree there’s a “slight increase,” but say it’s “substantially smaller than risk from other factors that exist on all farms, such as season of the year, age, breed, stage of lactation, farm sanitary conditions and parity.” It’s also been alleged rBST causes animals to go dry faster, negating the advantage of increased production; slaughter rates since the hormone was approved, the panel says, were equal to or lower than the pre-rBST period “for eleven out of twelve months of the year.”
Raymond insists that he tried to ensure the project was open and transparent. In Montreal, he says, “There was one person in the audience who is an expert on rBST, and he was very upset that we put [the higher IGF-1] in the paper, saying any increase is so miniscule as to be almost zero. I said, ‘Sir, that’s exactly the point I was trying to make—it was almost zero, but we cannot say zero.’ If I said it was zero, someone looking to beat us up would cite some paper that shows a 0.01% increase and say, ‘You lied’. Then the whole paper is discredited; my reputation is discredited.”
And, he says, the point is that they do not believe the increase in IGF-1 constitutes a health risk.   “Number one, IGF-1 is in milk that we consume on a daily basis, and this very, very minimal increase is almost zero. Number two, the bulk of that is not even absorbed through the GI track; it’s broken down through the normal enzymatic processes that go along with the digestion. And then lastly, let’s say you’re consuming three glasses of milk; the amount of IGF-1 in those three glasses of milk remains miniscule compared to the IGF-1 that is produced in your own body on a daily basis.”
But Dr. Samuel Epstein disputes this, and he does so bluntly. “There’s no question” the IGF-1 in treated cows is a health risk,” says Epstein, a professor emeritus of the University of Illinois School of Public Health. “In my book, What’s in Your Milk?, I detailed evidence showing that the relationship between consumption of rBGH milk and elevated levels of IGF-1 had been incriminated in major increased risks of three cancers—breast, colon and prostate cancers…We’re really dealing with, I would say, a criminal conspiracy by the self-interested industry that wants to continue production and sale of this highly toxic product.”
Now the chairman of the Chicago-based Cancer Prevention Coalition, Epstein has been highly critical of rBST since it was first proposed for the marketplace. His group petitioned the FDA to reject Monsanto’s application in 1990, and applied to have Posilac’s approval revoked in 2007. In addition to the IGF-1 claim, Epstein says milk from treated cattle is “contaminated by pus” due to the prevalence of mastitis, and “contaminated by antibiotics” that are needed to treat the mastitis. In addition, he says the increased level of growth hormone itself in the milk prevents the human body from employing a natural defense mechanism called apoptosis that rids the body of sub-microscopic cancers. And, he says, the hormone “makes cows sick…about 20 toxic veterinary effects” are listed on the product’s label.
Asked if the benefits Elanco outlines—more milk at a lower cost, and less impact on the environment—outweigh the risks he perceives, Epstein says, “I don’t know if that’s a serious question. You ask any consumer if they’re willing to have increased risks of breast, colon and prostate cancers, and if so, why aren’t consumers informed about these risks? The industry goes out of its way to deny these risks, even though they’re scientifically well documented.”
But Raymond rejects Epstein’s argument. “Take a glass of milk from an rBST-supplemented cow,” he says, “and a glass of milk from an organically-raised cow, and a glass of milk from a convention dairy farm without rBST, and conduct any tests you want…There is absolutely zero difference in the milk; when someone says, ‘My cows were not given rBST; therefore, we can put this label on it,’ we cannot confirm that from any testing available to mankind at this particular point in time. And if the milk is identical, how can it be a threat to human health?”
And Elanco contends the retailers, bottlers and restaurants overreacted. The company commissioned a study by Washington marketing consultants Statler Nagle, who said processors who shifted completely to rBST-free milk experienced “no discernible ‘sales bump’ from the changeover.” They estimated only 12-15% of consumers are concerned enough about hormones in milk to change their purchasing and consumption; of those, up to 50% already satisfy this preference by buying organic milk.
“I don’t believe that the great majority of the United States public have ever even thought about rBST,” says Raymond, who believes retailers responded to “a very vocal minority group.” The FDA only allows milk to be labeled as rBST-free if the label also states it has no health advantage over milk produced with the hormone. “There currently is a movement to get states to remove that stipulation,” says Raymond, “and I think that would be misleading to the American public.”