Demonstration of thiouracil excretion in bovine urine under cruciferous diet

Gaud Pinel (1) , Séverine Mathieu , Nora Cesbron , Hubert de Brabander (2) , Daniel Maume (1) , François André (1) , Bruno Le Bizec (1, 1)

1 LABERCA - Laboratoire d'étude des Résidus et Contaminants dans les Aliments
2 Chemical Analysis

Thyreostats are banned compounds in Europe since 1981 because of their carcinogenic and teratogenic properties. Until now, the identification of thiouracil in animal biological matrices is systematically interpreted as the consequence of an illegal administration. The present paper studies the influence of a cruciferous-based alimentation on the occurrence of thiouracil residue in urine. Urine sample collected on two heifers fed on cabbage or rapeseed cakes have been studied for their content in thiouracil after 3-iodobenzylbromide derivatisation and LC-ESI(-)-MS/MS analysis. Urines collected after cabbage or rapeseed feeding showed TU concentrations in the range 3–7 µg L-1 and 2–9 µg L-1, respectively, demonstrating the relation between a diet based on cruciferous and the occurrence of thiouracil in urine. Thiouracil was excreted in urine in the hours following cruciferous intake. Complete elimination (< 0.8 µg L-1) of the compound occurred within 5 days. The precursors in cruciferous explaining the thiouracil excretion in urine was proved not to be thiouracil itself.

Mots clés: Life Sciences

Gaud Pinel, Séverine Mathieu, Nora Cesbron, Hubert de Brabander, Daniel Maume, et al.. Demonstration of thiouracil excretion in bovine urine under cruciferous diet. Food Additives and Contaminants, 2006, 23 (10), pp.974-980. ⟨10.1080/02652030600806370⟩. ⟨hal-00577490⟩