Diethylstilbestrol (DES) is a synthetic estrogen that was used to prevent spontaneous abortion clinically. DES has also been employed as a growth-promoting agent to accelerate weight gain and improve feeding efficiency in cattle. Use of growth-promoting drugs for fattening livestock has been banned in the European Union since 1986 to protect consumers from possible harmful effects due to the intake of estrogen residues (Council of the European Communities (Eds.) Council Directive 86/469/EEC, 1986). For the analysis of anabolic steroids HPLC and GC/MS are described as physicochemical methods. Immunological assays like RIA or EIA are very often used as screening methods.

17ß-Estradiol (E2) is a C-18 steroid hormone (molecular weight 272.4 Da) produced mainly by the ovary and placenta, and in small amounts by adrenals and testes. 17ß-estradiol is a natural, low-level sexual hormone in bovine blood, at the level of a few pg/ml, except in pregnant animals. Therefore, a high hormone level in a non-pregnant animal can indicate that it has been illegally treated with an anabolic agent to increase its growth rate. The European Council limits the use of 17ß-estradiol for medical treatment of slaughtered animals because it has been found to be a potential carcinogen.

Ethinylestradiol, is a synthetic derivative of 17β-estradiol (E2), the major endogenous estrogen in humans and animals. Ethinylestradiol is released into the environment as a xenoestrogen from the urine. It is prohibited for use as resource in fattening in the European Community since 1988. In most EC countries urine is chosen as the matrix to screen for the presence of ethinylestradiol or other anabolic steroids. The CD Ethinylestradiol ELISA test kit offers excellent limits of detection for the screening of Ethinylestradiol residues in urine.

Zeranol (a-zearalanol) is a non-steroidal estrogenic growth promoter, used to increase the average daily live-weight gain in animals and to improve the food conversion efficiency. Zeranol is a semi-synthetic product derived from the naturally occurring mycotoxin zeralenone. Its administration has been banned within the EU (council directive 96/22/EEC), although its use is still widely permitted in other countries, including the USA. The Creative Diagnostics Zeranol ELISA test kit offers excellent cross reactivity screening zeranol residues in meat. Applicable sample types include tissue and urine.