Increased serum levels of advanced oxidation protein products and glycation end products in subjects exposed to low-dose benzene.

Simple aromatic hydrocarbon benzene occurs naturally in crude oil and petroleum. Benzene has been internationally recognised as a haematotoxin and carcinogen. The involvement of oxidative stress is a major susceptibility factors for benzene hematotoxicity in humans. Advanced oxidation protein products (AOPPs) and advanced glycation end products (AGEs) are modified structures which can serve as markers of oxidative stress. The aim of this study is to assess modification of circulating AOPPs and AGEs, as early markers of oxidative stress, in subjects exposed to low dose of benzene. Furthermore the genetic polymorphism of glutathione-S-transferase (GST) may be related to health effects of benzene exposure, in fact both genotype T1 (GSTT1) and M1 (GSTM1) are involved in the detoxification of benzene oxide. The study was performed on 54 workers oil refinery employees. A group of 32 healthy age-matched subjects was included as controls. The AOPPs serum levels in oil refinery employees were higher in a statistically significant way than those measured in controls, but there were no significant changes in serum AGE levels between both groups. However, GST polymorphisms had not influence on serum levels of both biomarkers, so demonstrating that production of circulating AGEs and AOPPs in benzene parity-exposed workers levels is not dependent by GST genotypes. We can conclude that, in this condition, AOPPs are more sensitive marker of low benzene exposure than AGEs.