Environmental Review: Trenbolone and Other Cattle Growth Promoters: Need for a New Risk-Assessment Framework

Abstract

The “six-pack” of hormone growth promoters used in feedlot cattle deserves closer investigation from researchers and policy makers. The potential effects of exposure to such compounds are of particular interest in the field of endocrine disruption, which focuses on the effects these compounds can have during sensitive developmental periods, rather than using a carcinogenesis model. Steroid hormones participate in a delicate balance during fetal development. Interference with that balance can lead to disruptions that manifest as health problems at birth and later in life. Although we need more studies of the effects of feedlot compounds on human and wildlife development, some industry and government literature leads consumers to conclude that all the data are in. Governmental reviews of the literature from the European Union (where hormone use is banned) and Australia (where hormones are used) reveal different attitudes and conclusions about the same body of research, and these differences may relate to a different understanding of the value of the endocrine-disruption model. It is important to approach examinations of the effects of trenbolone and other growth promoters without bias and to acknowledge that cattle growth promoter research in the context of endocrine disruption has just begun. The scientific jury is still out regarding whether introducing these compounds into the human food supply and ecosystems—research suggests that hormonally active feedlot effluent may harm wildlife—can be deleterious.