title: Determination of naturally occurring progestogens in bovine milk as their oxime derivatives using high performance liquid chromatography-electrospray ionization-tandem mass spectrometry.
abstract: BACKGROUND
  Hormones and hormone-like substances which are present in the environment have been repeatedly accused of being the cause of most endocrine disruption. However, the possible role of endogenous hormones in food of animal origin deserves to be discussed as well. The relation between steroid hormones and several human health problems has been previously reported, such as prostate and breast cancer, perturbation of human reproduction and endocrine disruption on humans and wildlife. This research is particularly concerned with cow's milk, which contains a considerable amount of sex hormones.
  
  
  RESULTS
  A liquid chromatography-tandem mass spectrometry method has been developed for the simultaneous detection and quantification of four naturally occurring steroid hormones in commercial bovine milk (pregnenolone (P5), progesterone (P4), 17-hydroxypregnenolone (17-OHP5), 17-hydroxyprogesterone (P4)). Oxime derivatives of steroids were analyzed in positive ionization and multiple reaction monitoring mode. Methodology has been validated according to Decision 2002/657/EC criteria.
  
  
  CONCLUSIONS
  This method has been successfully used in real samples. It is fast and easy-handling and provides a useful tool for the assessment of progestogens in bovine milk.
authors.affiliation: Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Veterinary Sciences, University of Santiago de Compostela, Lugo, Spain. patricia.regal@rai.usc.es
authors.forename: Patricia
authors.initials: P
authors.lastname: Regal
authors.forename: Carolina
authors.initials: C
authors.lastname: Nebot
authors.forename: Beatriz I
authors.initials: BI
authors.lastname: Vázquez
authors.forename: Alberto
authors.initials: A
authors.lastname: Cepeda
authors.forename: Cristina
authors.initials: C
authors.lastname: Fente
mesh_terms: D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D052244:Endocrine Disruptors / Q000032:analysis*; D008892:Milk / Q000737:chemistry*; D010091:Oximes / Q000032:analysis; D011372:Progestins / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
chemical_list: D052244:Endocrine Disruptors; D010091:Oximes; D011372:Progestins