S -phenylcysteine adduct concentration in serum albumin of countryside residents and factory workers in Estonia

Abstract

In this communication we present data on S-phenylcysteine (SPC) in human serum albumin in an Estonian cohort. A total of 112 human samples were collected from workers of a benzene processing plant in Kohtla-Järve, Estonia and another 56 samples from nearby countryside residents. Albumin was isolated using a sequential precipitation method designed for low volume plasma samples. The adducted cysteine derivatives were cleaved off from the albumin and subsequently derivatized to phenyl trifluorothioacetate (PTTA) derivatives. Derivatized adducts were subjected to GC/MS analysis utilizing negative chemical ionization and a selected ion monitoring (SIM) technique. The detection limit for the PTTA adduct was 0.2 pmol g−1 albumin and the limit of quantification was 2 pmol g−1 albumin. The method utilized deuterated SPC as an internal standard. The analysis revealed that adduct levels were also high in the population that was not occupationally exposed to benzene. The reason for this is unknown, but may cause problems if not of environmental origin, when one is attempting to monitor low level occupational or environmental benzene exposure.