title: An improved approach for accurate quantitation of benzene, toluene, ethylbenzene, xylene, and styrene in blood.
abstract: Widespread exposure to benzene, toluene, ethylbenzene, xylene, and styrene (BTEXS) and the potential for this exposure to cause health effects drives the need to develop improved methods for measuring exposure. In this work, we demonstrate our latest assay for quantifying BTEXS in blood and characterize sources of both positive and negative biases. This method involves blood sample collection using common techniques followed by static headspace sampling using solid-phase microextraction and gas chromatography/mass spectrometry analysis. We found that the greatest and unexpected source of positive bias was from contamination of butyl rubber materials used in sample preparation consumables such as Vacutainer stoppers, syringe plungers, and sample vial septa. Conversely, the primary cause of negative bias observed was from the diffusion loss of BTEXS from blood during transfer into sample vials. By minimizing or eliminating these and other sources of bias, we improved method accuracy and precision to within 10% while maintaining low-picogram per milliliter detection. Furthermore, upon comparison of these results with those from other laboratories, we observe substantially lower blood BTEXS levels reported to date for nonoccupationally exposed nonsmokers. A relatively unbiased method, as such, will help elucidate any potential associations between adverse health effects and human exposure to low levels of BTEXS.
authors.affiliation: Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Chambers
authors.forename: David O
authors.initials: DO
authors.lastname: McElprang
authors.forename: Michael G
authors.initials: MG
authors.lastname: Waterhouse
authors.forename: Benjamin C
authors.initials: BC
authors.lastname: Blount
mesh_terms: D001554:Benzene / Q000032:analysis*; D001555:Benzene Derivatives / Q000097:blood*; D008401:Gas Chromatography-Mass Spectrometry / Q000295:instrumentation / Q000379:methods; D006801:Humans; D016014:Linear Models; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D020058:Styrene / Q000097:blood*; D014050:Toluene / Q000097:blood*; D014867:Water / Q000737:chemistry; D014992:Xylenes / Q000097:blood*
chemical_list: D001555:Benzene Derivatives; D014992:Xylenes; D014867:Water; D014050:Toluene; D020058:Styrene; D001554:Benzene; C004912:ethylbenzene