Since rbST was approved for use by the Food and Drug Administration (FDA) in the early 1990s, its safety has been reaffirmed by the scientific community. Scientists tell us that rbST is species-specific, meaning that it is biologically inactive in humans. Also, pasteurization destroys 90 percent of bST and rbST in milk. Any trace amounts of bovine somatotropin that remain after pasteurization of milk are broken down in the human gut into inactive protein fragments, like any other dietary protein. Numerous scientific studies have shown there is no significant difference between milk from rbST-supplemented and non-rbST-supplemented cows. For this reason, the FDA has established that dairy products from cows treated with rbST do not need to be labeled.