title: A SPME-GC/MS procedure for the determination of fatty acid ethyl esters in hair for confirmation of abstinence test results.
abstract: Fatty acid ethyl esters (FAEE), direct metabolites of ethanol, are suitable alcohol markers that can be detected in different tissues. The determination of FAEE in hair can help to evaluate social and excessive alcohol consumption. Due to the presence of FAEE in the hair of teetotalers, proving alcohol abstinence seems to be impossible. To verify these results, an solid phase micro extraction-gas chromatography/mass spectrometry procedure for the determination of the four FAEE: ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate in hair was validated with special focus on low concentration levels. Besides very high sensitivity (limits of detection between 0.005 and 0.009 ng/mg), good results for linearity, precision and accuracy, recovery and stability were achieved. In addition, 73 hair samples with measured ethyl glucuronide (EtG) concentrations between 4 and 10 pg/mg were analyzed for FAEE. By using the following cut-offs: EtG: 7 pg/mg, FAEE: 0.2 ng/mg a satisfying matching rate of 72.6% was found. This shows that FAEE can be determined to verify borderline EtG concentrations even in the context of abstinence tests. However, the diversified influencing factors on analyte concentrations in hair, which may explain the large deviations between EtG and FAEE results observed in some cases, have to be mentioned when interpret ambiguous results.
authors.affiliation: Institute of Forensic Medicine, University Hospital Bonn, Stiftsplatz 12, 53111 Bonn, Germany elena.albermann@uni-bonn.de.
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Albermann
authors.affiliation: Institute of Forensic Medicine, University Hospital Bonn, Stiftsplatz 12, 53111 Bonn, Germany.
authors.forename: Burkhard
authors.initials: B
authors.lastname: Madea
authors.affiliation: Institute of Forensic Medicine, University Hospital Bonn, Stiftsplatz 12, 53111 Bonn, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Musshoff
mesh_terms: D000428:Alcohol Drinking; D005227:Fatty Acids / Q000032:analysis* / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D005965:Glucuronates / Q000032:analysis; D006197:Hair / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D009226:Myristates / Q000032:analysis; D009829:Oleic Acids / Q000032:analysis; D010169:Palmitic Acids / Q000032:analysis; D015203:Reproducibility of Results; D052617:Solid Phase Microextraction / Q000379:methods*; D013228:Stearates / Q000032:analysis; D015813:Substance Abuse Detection / Q000379:methods*
chemical_list: D005227:Fatty Acids; D005965:Glucuronates; D009226:Myristates; D009829:Oleic Acids; D010169:Palmitic Acids; D013228:Stearates; C093924:ethyl glucuronide; C032396:ethyl myristate; C026345:ethyl stearate; C007680:ethyl palmitate; C033180:ethyl oleate