In fact, there is no substantive difference between either products, and both are completely safe to drink. Recombinant bovine somatotropin rBST is the commercially produced version of bovine somatotropin BST , a protein hormone naturally produced in cows' pituitary glands.
Both are identical but for a single extra amino acid in rBST. In the s, Cornell scientists discovered that injecting cows with additional BST drastically increased dairy cows' milk production with no adverse effects. In the early s, the companies Monsanto and Genentech teamed up to create rBST, which could be produced in vast quantities.
For more than a dozen years, scientists extensively studied the hormone, dairy cows, and the resulting milk produced for safety, efficacy, and animal welfare. 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.
This failing is best characterized as a disease. It is present to varying extents in the scientific community, is spread by textbooks and editorial conventions, has readily identifiable symptoms, and results in costly and debilitating outcomes. In the s, Daniel Kahneman and Amos Tversky began to look at how people make decisions under uncertainty.
They found that behind the illusion of rational thought lay a psychological pathology of unexpected proportions. People, it turns out, are barely rational, even in life and death circumstances. Their work has produced some wonderful generalizations. Some are funny. Others are plain depressing.
The mistakes that people make can be summarized under headings that make a kind of pathology that is identifiable and predictable and perhaps even treatable.
Not everyone reacts in seemingly unreasonable ways, and not in all circumstances. But most people do, most of the time. Kahneman, Tversky and their colleagues also found that much of the apparent arbitrariness of decisions can be explained by the context in which decisions are set. In , Kammen and Hassenzahl described a beautiful contradiction that illustrates the importance of context.
Two artificial substances were in our food in the s: Saccharin used to sweeten the taste of things such as diet soda and Alar a pesticide used on apple and pear crops. Congress passed legislation to make Saccharin legal after public outcry.
In contrast, in the s, the EPA concluded the amount of Alar reaching consumers was too small to warrant banning it. A public interest group released a report that children are particularly susceptible because they weigh less, consume a lot of apples and apple juice, and are more susceptible to toxins than adults.
The public outcry that followed the release of the report convinced the maker of Alar to withdraw it from the market. The two chemicals have nearly the same potential to form cancers and appear in the general population with the same kinds of exposures. Yet the extrapolations from high doses to low doses in Saccharin were ridiculed, whereas the same extrapolations for Alar were accepted. One chemical was banned and people demanded its return. The other was deemed safe and people demanded that it be withdrawn.
Cognitive psychologists and risk analysts such as Paul Slovic and his colleagues delight in explaining these apparent contradictions. In contrast, people could avoid Alar only by avoiding apple products altogether. In addition, Saccharin has benefits, such as reducing problems for diabetics and reducing the risk of heart disease in overweight people.
In addition, the most susceptible group was children. Scientists, like other people, are very poor judges of risky circumstances. Yet scientists feel that they are immune to the failings that plague ordinary humans.
This delusion makes us susceptible to the scientific disease. Take the case of Saccharin and Alar. The decision by the public to accept one and not the other is contradictory only if you are myopic enough to look just at the technical risks. Very little else was the same: the context, the framing, the degree of control, the prospects of benefits, and the impact groups were completely different.
Most scientists suffer from technical myopia. Our solution to problems like these is to argue that if people just understood the technical details, they would be rational.
This train of thought turns ugly when we scientists take it upon ourselves to provide people with both the information, and the decisions. We create panels of experts comprised largely of people like ourselves , and the priesthood of scientists then decides the questions, collects the data, interprets them, and makes the decisions. In my view, when this happens, we have imposed on the rest of society the values of a bunch of mostly middle-aged, middle-class men and women who often are compromised by conflicts of interest.
In such circumstances, we are not to be trusted. We scientists are typically, heroically optimistic about our ability to predict. Many experts are wildly and unjustifiably confident about their ability to guess parameters, even within their field of technical expertise.
Unfortunately, it is very difficult to distinguish a reliable expert from a crank. Often, we depend on ecological monitoring and surveillance systems to reassure ourselves that our decisions about putative environmental impacts are sound and that ecological systems are in control. Recombinant bovine growth hormone rBGH is a synthetic man-made hormone that is marketed to dairy farmers to increase milk production in cows. This document summarizes what is known about the product and its potential effects on health.
The human form of growth hormone, also called somatotropin , is made by the pituitary gland. It promotes growth and cell replication. Recombinant bovine growth hormone rBGH or recombinant bovine somatotropin rBST refers to bovine growth hormone that is made in a lab using genetic technology. Some rBGH products on the market differ chemically from a cow's natural somatotropin by one amino acid. Both the natural and recombinant forms of the hormone stimulate a cow's milk production by increasing levels of another hormone known as insulin-like growth factor IGF Concerns about possible health effects on humans from milk produced using rBGH have focused on 2 main issues.
If it does, would this be expected to have any health effects in people, including increasing the risk of cancer? Several scientific reviews have looked at these issues and are the main focus of this document.
Second, cows treated with rBGH tend to develop more udder infections mastitis.
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