The Fate of Trenbolone Acetate and Melengestrol Acetate after Application as Growth Promoters in Cattle: Environmental Studies

• Published in: Environmental health perspectives Vol. 109; no. 11; pp. 1145 - 1151
• Main Authors: Schiffer, Bettina, Daxenberger, Andreas, Meyer, Karsten, Heinrich H. D. Meyer
• Format: Journal Article
• Language: English
• Published: United States National Institute of Environmental Health Sciences. National Institutes of Health. Department of Health, Education and Welfare 01.11.2001; National Institute of Environmental Health Sciences
• Subjects: Acetates; Agriculture; Anabolic Agents - administration & dosage; Anabolic Agents - pharmacokinetics; Animal Husbandry; Animals; Canals; Cattle; Chromatography, High Pressure Liquid; Ecosystem; endocrine disruptors; Environmental Exposure; Feces; Female; Glucocorticoids - administration & dosage; Glucocorticoids - pharmacokinetics; Hormones; Liquid manure; Manure; Manure storage; Mass Spectrometry; melengestrol acetate; Melengestrol Acetate - administration & dosage; Melengestrol Acetate - pharmacokinetics; Quantification; Soil Pollutants - analysis; Solids; Steroids; trenbolone acetate; Trenbolone Acetate - administration & dosage; Trenbolone Acetate - analogs & derivatives; Trenbolone Acetate - pharmacokinetics
• ISSN: 0091-6765; 1552-9924
• DOI: 10.1289/ehp.011091145

The steroids trenbolone acetate (TbA) and melengestrol acetate (MGA) are licensed as growth promoters for farm animals in several meat-exporting countries. Although many studies have explored their safety for both animals and consumers, little is known about their fate after excretion by the animal. Our study aimed to determine the residues and degradation of trenbolone and MGA in solid dung, liquid manure, and soil. In animal experiments lasting 8 weeks, cattle were treated with TbA and MGA. Solid dung and, in case of trenbolone, liquid manure were collected and spread on maize fields after 4.5 and 5.5 months of storage, respectively. Determination of the hormone residues in all samples included extraction, clean-up (solid-phase extraction), separation of metabolites and interfering substances by HPLC (RP-18), and quantification by sensitive enzyme immunoassay. Procedures were validated by mass spectrometry (MS) methods. During storage of liquid manure the level of trenbolone decreased from 1,700 to 1,100 pg/g (17α-isomer), corresponding to a half-life of 267 days. Before storage, the concentrations in the dung hill ranged from 5 to 75 ng/g TbOH and from 0.3 to 8 ng/g MGA. After storage, levels up to 10 ng/g trenbolone, and 6 ng/g MGA were detected. In the soil samples trenbolone was traceable up to 8 weeks after fertilization, and MGA was detected even until the end of the cultivation period. The results show that these substances should be investigated further concerning their potential endocrine-disrupting activity in agricultural ecosystems.