title: Determination of hemoglobin adducts following oral administration of 1-nitropyrene to rats using gas chromatography-tandem mass spectrometry.
abstract: 1-Nitropyrene (1-NP) has successfully been used as a marker for environmental monitoring of exposure to diesel exhaust. This study presents a sensitive and selective method for detection of Hb adducts after oral administration of a single dose 1-NP to rats, by measuring 1-aminopyrene (1-AP) after in vitro hydrolysis of the adducts. Released 1-AP was extracted with hexane and derivatized with heptafluorobutyric acid anhydride prior to GC-MS-MS analysis. Optimal conditions for the release of 1-AP were hydrolysis under nitrogen, in 1 M NaOH at 70 degrees C for 60 min. Analysis of a stock solution of Hb adducts of 1-NP utilizing these conditions showed to be reproducible over a period of several weeks with a coefficient of variance of 9.5%. The determination limit was 10-20 pg 1-AP per 70-90 mg globin. A study of the time course of Hb adduct formation showed a fast absorption and an early peak concentration of released 1-AP, approximately 39 pg 1-AP/mg globin at 3 h after exposure. After the maximum was reached, 1-AP concentrations decreased bi-phasically. Initially a fast decline was observed, followed by a slow decrease to 5.9+/-1.9 pg 1-AP/mg globin at 24 h after administration.
authors.affiliation: Toxicology Department 235 CPK-II, University of Nijmegen, The Netherlands.
authors.forename: Y M
authors.initials: YM
authors.lastname: van Bekkum
authors.forename: P T
authors.initials: PT
authors.lastname: Scheepers
authors.forename: P H
authors.initials: PH
authors.lastname: van den Broek
authors.forename: D D
authors.initials: DD
authors.lastname: Velders
authors.forename: J
authors.initials: J
authors.lastname: Noordhoek
authors.forename: R P
authors.initials: RP
authors.lastname: Bos
mesh_terms: D000284:Administration, Oral; D000818:Animals; D015415:Biomarkers / Q000097:blood; D002274:Carcinogens, Environmental / Q000032:analysis* / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D006454:Hemoglobins / Q000378:metabolism*; D006868:Hydrolysis; D008297:Male; D011721:Pyrenes / Q000032:analysis* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D015415:Biomarkers; D002274:Carcinogens, Environmental; D006454:Hemoglobins; D011721:Pyrenes; C032668:1-nitropyrene