(NaturalNews) Beef produced in the United States contains dangerously high levels of natural and synthetic hormones, warns Dr. Samuel S. Epstein of the Cancer Prevention Coalition.According to Epstein, more than half of all beef cows slaughtered in the United States each year have been treated with either the natural hormones estrogen, progesterone or testosterone, or the synthetic hormones melengesterol, trenbolone or zeranol. Hormone-emitting pellets are implanted under each cow's ear when it enters the feedlot, then again 50 days later. After another 50 days, the cow is slaughtered.The hormones cause the cows to rapidly put on weight, leading to approximately $80 more profit per animal."Not surprisingly, but contrary to longstanding claims by the [FDA] and the U.S. Department of Agriculture (USDA), residues of these hormones in meat are up to 20-fold higher than normal," Epstein said in a press release. "Still higher residues result from the not uncommon illegal practice of implantation directly into muscle. Furthermore, contrary to misleading assurances, meat is still not monitored for hormone residues."The FDA insists that hormone levels in U.S. beef are safe and normal, but does not require any testing to back up this claim.According to Epstein, however, tests reveal that an eight-year-old boy eating two hamburgers in one day would be exposed to enough estradiol to increase his body's levels of the hormone by 10 percent.Exposure to external hormones is well known to increase the risk of cancer, reproductive dysfunction and other health problems."Increased levels of sex hormones are linked to the escalating incidence of reproductive cancers in the United States since 1975 - 60 percent for prostate, 59 percent for testis and 10 percent for breast," Epstein said.Women in the United States are five times more likely to get breast cancer than women in the European Community or other countries that have banned the production or importation of hormonal beef Sources for this story include: www.organicconsumers.org