title: Urinary di-(2-ethylhexyl) phthalate metabolites for detecting transfusion of autologous blood stored in plasticizer-free bags.
abstract: BACKGROUND
  Autologous blood transfusion (ABT) efficiently increases sport performance and is the most challenging doping method to detect. Current methods for detecting this practice center on the plasticizer di(2-ethlyhexyl) phthalate (DEHP), which enters the stored blood from blood bags. Quantification of this plasticizer and its metabolites in urine can detect the transfusion of autologous blood stored in these bags. However, DEHP-free blood bags are available on the market, including n-butyryl-tri-(n-hexyl)-citrate (BTHC) blood bags. Athletes may shift to using such bags to avoid the detection of urinary DEHP metabolites.
  
  
  METHODS
  A clinical randomized double-blinded two-phase study was conducted of healthy male volunteers who underwent ABT using DEHP-containing or BTHC blood bags. All subjects received a saline injection for the control phase and a blood donation followed by ABT 36 days later. Kinetic excretion of five urinary DEHP metabolites was quantified with liquid chromatography coupled with tandem mass spectrometry.
  
  
  RESULTS
  Surprisingly, considerable levels of urinary DEHP metabolites were observed up to 1 day after blood transfusion with BTHC blood bags. The long-term metabolites mono-(2-ethyl-5-carboxypentyl) phthalate and mono-(2-carboxymethylhexyl) phthalate were the most sensitive biomarkers to detect ABT with BTHC blood bags. Levels of DEHP were high in BTHC bags (6.6%), the tubing in the transfusion kit (25.2%), and the white blood cell filter (22.3%).
  
  
  CONCLUSIONS
  The BTHC bag contained DEHP, despite being labeled DEHP-free. Urinary DEHP metabolite measurement is a cost-effective way to detect ABT in the antidoping field even when BTHC bags are used for blood storage.
authors.affiliation: Swiss Laboratory for Doping Analyses, University Centre of Legal Medicine, Lausanne and Geneva, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Leuenberger
authors.affiliation: Swiss Laboratory for Doping Analyses, University Centre of Legal Medicine, Lausanne and Geneva, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland.
authors.forename: Laura
authors.initials: L
authors.lastname: Barras
authors.affiliation: Swiss Laboratory for Doping Analyses, University Centre of Legal Medicine, Lausanne and Geneva, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland.
authors.forename: Raul
authors.initials: R
authors.lastname: Nicoli
authors.affiliation: Swiss Laboratory for Doping Analyses, University Centre of Legal Medicine, Lausanne and Geneva, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland.
authors.forename: Neil
authors.initials: N
authors.lastname: Robinson
authors.affiliation: Swiss Laboratory for Doping Analyses, University Centre of Legal Medicine, Lausanne and Geneva, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland.
authors.forename: Norbert
authors.initials: N
authors.lastname: Baume
authors.affiliation: Transfusion Interrégionale CRS, Epalinges, Switzerland.
authors.forename: Niels
authors.initials: N
authors.lastname: Lion
authors.affiliation: Transfusion Interrégionale CRS, Epalinges, Switzerland.
authors.forename: Stefano
authors.initials: S
authors.lastname: Barelli
authors.affiliation: Transfusion Interrégionale CRS, Epalinges, Switzerland.
authors.forename: Jean-Daniel
authors.initials: JD
authors.lastname: Tissot
authors.affiliation: Swiss Laboratory for Doping Analyses, University Centre of Legal Medicine, Lausanne and Geneva, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland.
authors.forename: Martial
authors.initials: M
authors.lastname: Saugy
mesh_terms: D000328:Adult; D001793:Blood Preservation; D001803:Blood Transfusion; D001804:Blood Transfusion, Autologous; D004311:Double-Blind Method; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D010795:Phthalic Acids / Q000032:analysis / Q000378:metabolism*; D010968:Plasticizers; D055815:Young Adult
chemical_list: D010795:Phthalic Acids; D010968:Plasticizers; C032279:phthalic acid