Development of nontarget method based on GC-QTOF-HRMS for analyzing organic pollutants in human serum

Traditional targeted analyses often overlook unknown or emerging contaminants, highlighting the significance of nontarget and suspect screening approaches. A novel and high-sensitivity methodology for nontarget analysis of organic pollutants in human serum was newly-developed based on gas chromatography coupled with quadrupole time-of-flight high-resolution mass spectrometry. The extraction protocol employing an acetonitrile-ethyl acetate (9:1, V:V) mixture significantly improved the extraction efficiency while minimizing matrix effect. A hybridized analytical strategy integrating nontarget and suspect screening was developed to achieve comprehensive identification and classification of pollutants, employing the National Institute of Standards and Technology (NIST) 20 library and Agilent Technologies Personal Compound Database and Library (PCDL). This approach successfully characterized 273 organic contaminants spanning 12 categories, including polycyclic aromatic hydrocarbons (PAHs) and their derivatives, esters, and phenolic compounds in human serum, with a significant increase in detection specificity compared to conventional workflows. The methodology used serum samples of the workers from coking industry, revealing widespread contamination dominated by PAHs and PAH derivatives. Among the target analytes, three were identified solely by NIST and six solely by PCDL, indicating the complementary benefits of combining these different databases. Notably, this work reported the first confirmed detection of 2-naphthalenamine in human serum. This optimized approach demonstrates enhanced sensitivity and reliability in serum analysis, advancing biomonitoring capabilities and providing a deep understanding of human exposure to environmental pollutants.