By , the Food and Drug Administration recognized rBST's solid scientific standing and approved it for commercial sale. A small injection every two weeks of a plant oil formulation containing rBST could increase a cow's daily milk yield by ten pounds with no ill effects for the cow. Yet, as milk produced by cows injected with this small amount of rBST slowly came onto the market, a campaign quickly formed to drive it out. Critics claimed that it was unnatural, of lesser quality, and contributed to breast cancer.
They were misleading or wrong on all counts. Arguing "naturalness" is irrelevant and meaningless, with no bearing on the quality of a thing. Cyanide , for example, is natural to outer space and nature but you'd never want to drink it. Moreover, milk produced with the aid of rBST is no less nutritious. Lastly, the breast cancer scare-mongering stemmed from the notion that rBST milk contains more of a hormone called insulin-like growth factor 1 IGF-1 , which is naturally produced by various tissues in the human body and may, as a side effect of its normal bodily functions , contribute to the risk of breast cancer.
Milk produced with rBST does indeed have a little more IGF-1 than normal milk, but the difference is so small that the average milk-drinking adult would receive just 0. There are two bad arguments for banning such labels. The first — that it is impossible to determine from the milk whether the cow was injected with rBGH — is the reason cited in the bill language.
The second — that a proliferation of 'no rBGH' labels will train consumers to distrust the product — is the real motivation. The first argument can be disposed of easily: it is already illegal to make false claims about a product. The second argument may seem more convincing. There is no firm scientific evidence that injecting cows with rBGH affects human health in any way, but prevalent labelling touting the absence of rBGH would suggest to consumers that there are some differences.
The hormone injections may not affect the milk, but they are rough on the cows: producing all that milk causes problems such as udder infections and lameness. For some consumers, this may be a sufficient reason to avoid milk from dairies using the injections. Indeed, it was, in part, animal welfare that led Canada and the European Union to ban them. There are good reasons not to ban accurate labels. More information means that consumers can be more discerning, and not just about their own health.
They can vote with their purchases for farming practices they prefer. And if a company wants to use a technology with a bad reputation, it is the firm's responsibility to educate the consumer about why it is beneficial. If consumers choose irrationally to reject it, that is their prerogative. Sales of Monsanto's rBST product, Posilac, were allowed to begin on February 3, following completion of a report by the federal executive branch reviewing available evidence on the impact of rBST use.
Despite the FDA approval and the availability of Posilac for use on dairy farms, there continues to be a great deal of controversy surrounding rBST. Some have expressed concern about human health effects due to potential increases in milk antibiotic residues resulting from alleged higher levels of mastitis in cows administered rBST. Other human health concerns include increases in IGF-1 Insulin-like growth factor levels, and the possible spread of a central nervous system disorder known as spongiform encephalopathies.
Other potential human health concerns have also been expressed, but these are the principal ones. Among bovine health concerns that have been raised are lowered resistance to infectious diseases, increased stress, increased mastitis, and lowered fertility.
This memo describes rBST and the principal human and animal health concerns of those opposed to and in favor of its use. We do not critique the logic or basis of the positions, or try to reconcile them. Indeed, the proponents and opponents of rBST use are often not addressing identical concerns or using the same data, and interpretations of the same data vary.
The memo presents the major human and animal health issues in the debate over rBST, providing general background to facilitate more in-depth evaluation and a basis on which further questions can be posed to both sides.
Bovine somatotropin BST , also known as bovine growth hormone BGH , is a natural protein hormone that controls the amount of milk cows produce. Unlike steroids, it is a metabolic, not a growth hormone that is released from the anterior pituitary gland of cattle, a small gland located at the base of the brain.
As with any hormone, it is transported in the bloodstream to the body organs it affects. Recombinant bovine somatotropin rBST , also known by its Monsanto trade name Posilac, is a biosynthetic version of the naturally occurring pituitary hormone in cows. BST research with milk cows was first reported by Russian scientists in who found that injecting the animals with bovine pituitary extracts increased milk yield.
Until the introduction of recombinant DNA technology only small and impure amounts of BST could be obtained from slaughterhouses. The use of such technology made it possible to put the BST gene into bacteria which could then be induced to produce commercial quantities of the hormone.
Somatotropin is a protein, and like all proteins is composed of amino acids which are combined in particular sequences. IGF-1 is carried to a cow's mammary gland where it stimulates milk production. Thus, while responses vary among and within herds, cows with low or medium production tend to show a higher proportional increase. Heating by cooking or pasteurization inactivates BST that may exist in milk or meat.
Traces of BST is found in all milk, and the amount in milk from cows injected with rBST is no greater than from those not administered the supplement. Because it is impossible to differentiate between BST levels in milk from cows given rBST supplements and those that are not, there is no test to distinguish between milk from supplemented and nonsupplemented animals.
Antibiotic Residues. Mastitis is the most common disease of dairy cows and is treated with antibiotics which leave residues in milk.
But, there was no evidence that these cases of mastitis were more difficult to treat based on their duration. On a per-unit milk basis the increase about 0. In considering the possible increase in antibiotic use, the executive branch study relied on the fact that state and federal regulatory bodies monitor milk supplies for drug residues and require disposal of milk with levels above standards see, OLR report R, Antibiotics in Milk.
Moreover, dairy producers who experience an increased incidence of mastitis would likely reevaluate their use of BST. The Consumer Policy Institute of Consumers Union, publisher of Consumer Reports , finds that FDA underestimates mastitis incidence, ignores widespread use of illegal antibiotics, and relies too heavily on a limited program of residue testing M.
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