Application of stable carbon isotope analysis to the detection of 17beta-estradiol administration to cattle.
The use of anabolic agents in food producing animals is prohibited within the EU since 1988 (96/22/EC directive). The control of the illegal use of natural steroid hormones in cattle is still an exciting analytical challenge as far as no definitive method and non-ambiguous analytical criteria are available. The ability of gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) to demonstrate the administration of 17beta-estradiol to bovine has been investigated in this paper. By comparison of 13C/12C isotopic ratio of main urinary estradiol metabolite, i.e. 17alpha-estradiol, with two endogenous reference compounds (ERCs), i.e. dehydroepiandrosterone (DHEA) and 5-androstene-3beta,17alpha-diol, the differentiation of estradiol metabolite origin, either endogenous or exogenous, has been proved to be achievable. After treatment, the delta(13)C(VPDB)-values of 17alpha-estradiol reached -27 per thousand to -29 per thousand, whereas delta13CVPDB-values of DHEA remained between -13 per thousand and -20 per thousand depending on the diet, maize and grass, respectively. A significant difference of delta13CVPDB between ERCs and 17alpha-estradiol was measurable over a period of 2 weeks after estradiol ester administration to the animal.
Buisson
C
C
LABERCA, Ecole Nationale Vétérinaire de Nantes, Route de Gachet, Atlanpôle La Chantrerie, BP 50707, 44087 Nantes Cedex 03, France.
Hebestreit
M
M
Weigert
A Preiss
AP
Heinrich
K
K
Fry
H
H
Flenker
U
U
Banneke
S
S
Prevost
S
S
Andre
F
F
Schaenzer
W
W
Houghton
E
E
Le Bizec
B
B
D015114:Androstenediol / Q000031:analogs & derivatives / Q000652:urine; D000818:Animals; D002247:Carbon Isotopes / Q000032:analysis*; D002417:Cattle; D003687:Dehydroepiandrosterone / Q000652:urine; D004958:Estradiol / Q000008:administration & dosage*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D012015:Reference Standards
D002247:Carbon Isotopes; D003687:Dehydroepiandrosterone; D004958:Estradiol; C033537:5-androstene-3 beta,17 beta-diol sulfate; D015114:Androstenediol