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Introduction: Naphthalene, the most volatile polycyclic aromatic hydrocarbon (PAH), was recently classified as possible human carcinogen by International Agencies for Research on Cancer Humans may be exposed to naphthalene from a wide variety of sources, including occupation, environment, personal habits. We assessed urinary excretion of 1-naphthol (1-NAF), biomarker of naphthalene exposure, in non-occupationally exposed subjects., Materials and Methods: Urinary 1-NAF, 1-hydroxypyrene (1-OHP), biomarker of exposure to pyrene and cotinine, biomarker of smoking habits, were measured in 104 adults (53 men, 51 women)., Results: 1-NAF concentrations overlapped in males and females (median: men 0.35 Microg/g creat; women: 0.46 microg/g creat). Median concentration of 1-NAF was 6-fold higher in smokers compared to nonsmokers (respectively, 7.7 microg/g creatinine vs 1.3 microg/g creatinine). Between smokers, urinary cotinine was positively correlated to 1-naphthol (rho: 0.69; p < 0.01) and 1-OHP (rho: 0.53; p < 0.01). Higher 1-OHP concentrations were found in smokers (median: smokers 0.16 microg/g creatinine, not-smokers 0.05 microg/g creatinine;)., Conclusions: In our study population, we found that 1-NAF excretion is much higher as compared to 1-OHP excretion. This is due to the ubiquitous presence of naphthalene in the environment. Smoking considerably increase the exposure to naftalene.

Unlabelled: Chronic inflammation and reactive oxygen species (ROS) production induced by crystalline silica are involved in the development of silicosis and lung cancer pathogenesis. ROS can generate lipid peroxydation of cell membranes that can produce methylglyoxal (MG), a strong cell proliferation inhibitor and apoptosis inducer. MG is naturally removed by glyoxalase I (GI) and glyoxalase II (GII) through a glutathione (GSH) dependent mechanism. Therefore mRNA expression of glyoxalases is correlated to MG concentration and oxidative stress., Objectives: evaluate oxidative stress induced by crystalline silica by glyoxalases mRNA expression and methylglyoxal concentration, Material and Methods: In bronchial epithelial cell culture (BEAS-2B), exposed to 50 microg/cm2 crystalline silica (Min-U-Sil 5), for 2, 6, 12, and 24 hours, GI and GII mRNA levels and MG intracellular concentration were measured respectively by Real-Time PCR and HPLC., Results: Crystalline silica exposure induced a significant reduction in mRNA expression of glyoxalases and an increase of MG intracellular concentration., Conclusions: The results suggest a possible use of MG and mRNA expression of GI and GII as crystalline silica induced oxidative stress indicators.