Steroids are a synthetic version of the male hormone testosterone. Anabolic refers to a substance that promotes growth. When taken internally, steroids will, in conjunction with weight training, promote extraordinary weight gain and muscular development. These characteristics make steroids attractive to participants in football, professional wrestling, track and field, swimming, and bodybuilding, as well as other activities that require muscular development for improved performance. Taken over a period of time, steroids can have detrimental effects on the body. Men may suffer from hypertension, sterility, female breast development, premature hair loss, infections, cysts, or other problems that result from multiple injections, and irreversible heart or liver damage. Steroid use also increases the risk of cancer. Because women, by nature, have little testosterone in their bodies, steroids pose an even greater threat to them. The illegal sale of anabolic steroids has been a felony under U.S. Federal law since 1988. Effective February 27, 1991, the law placed 27 anabolic steroids and their derivatives into Schedule III of the Controlled Substances Act. The manufacture and distribution of fake steroids are prosecuted federally under two statutes. One section of this article describes the operations of the steroid dealer arrested in undercover operation Equine, which led to the indictment of several Canadian suppliers. The article also notes the importance of investigators' learning to distinguish between steroid products and their accompanying testosterone derivatives because of the myriad of steroid products that contain various testosterone derivatives. A table shows steroid products and their testosterone derivatives. 15 notes