15-F₂t isoprostane as biomarker of oxidative stress induced by tobacco smoke and occupational exposure to formaldehyde in workers of plastic laminates

Background: Formaldehyde (FA) is a suspected human carcinogen capable of inducing oxidative stress through different metabolic ways. FA may originate from tobacco smoke, several environmental sources, as well as occupational sources, like furnishing industries specialized in the production of pressed-wood and laminate products.Object: Our aim was to investigate the role of tobacco smoke and occupational exposure to air-FA in the induction of oxidative stress status by comparing FA-exposed with non-exposed subjects who smoked or did not.Methods: Enrollment of 105 subjects was made in an industry of plastic laminates, including both workers directly exposed to FA and non-exposed office personnel, as control group. 15-F2t isoprostane (15-F2t IsoP), detected by ELISA technique and urinary cotinine, detected by GC-MS, were used for evaluating oxidative stress and tobacco smoke exposure, respectively. Air-FA levels were detected by GC-MS.Results: FA concentrations were significantly higher in subjects occupationally exposed than the controls. Smoking habits and air-FA exposures independently induce the formation of 15-F2t IsoP and increase the oxidative stress level.Conclusions: Our findings show, for the first time, that 15-F2t IsoP presents a dependency from both the smoking habit and air-FA exposures, and consequently, that these breathable pollutants could be considered as two important independent risk factors in increasing the oxidative stress in human beings