ABSTRACT
This chapter presents an analysis of available information on potential risks of breast and gastrointestinal cancers from insulin-like growth factor 1 (IGF-1) in synthetic bovine growth hormones (rBGH) milk. A summary report of the 1990 National Institutes of Health Technology Conference noted that IGF-1 levels in unspecified samples of rBGH milk were 3.5 to 13 ng/ml, in contrast to 1.5 to 8 ng/ml in untreated cows. There are no published studies, in the scientific literature or in Food and Drug Administration (FDA) or industry reports, on the oral activity of IGF-1. FDA, however, in 1990 released a highly condensed summary of 1989 toxicity tests by the two major rBGH industries, Eli Lilly & Co. and Monsanto Agricultural Co. Consumption of rBGH milk would expose infants and young children to IGF-1 levels substantially in excess of the safety margin based on the 0.02 mg/kg lowest observed effect level identified in the Monsanto/Hazleton oral toxicity test.
