The Drugs in US Meat–We’re Eating What?

by Project Censored
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Oestradiol-17, zeranol, trenbolone acetate and melengestrol acetate are hardly household names but these synthetic growth hormones are routinely administered to livestock, especially beef in the US and you won’t find them listed on a food package label. Another drug, ractopamine, a beta agonist used for asthma treatment is used to increase muscle mass in pigs and turkeys and is used right up until the time of slaughter. It is banned in 160 countries and even China seized US pork in 2007 due to ractopamine residues that it believed was making people sick.

Although many of these drugs are withdrawn from the animals before slaughter, ractopamine is not:  It is given to cattle and pigs for the last 28 days of their lives and the last 7—14 days for turkeys. The European Commission’s Scientific Committee on Veterinary Measures believes there is a association between these steroid hormones and certain cancers, specifically breast and prostate cancers, and that meat consumption is the culprit. The US has the highest rates of both and also uses the most hormones in its meat production. Since 1989, Europe has banned most US meat.


Rosenberg, Martha, “We’re Eating What? The Drugstore in U.S. Meat,” Alternet, Dec. 2, 2012,

Student Researcher: Alistair Shanks, San Francisco State University

Faculty Evaluator: Kenn Burrows, San Francisco State University