DOI: 10.1016/j.tiv.2019.03.030
Méausoone C1, El Khawaja R1, Tremolet G1, Siffert S1, Cousin R1, Cazier F2, Billet S1, Courcot D3, Landkocz Y1.
1 UCEIV – EA4492, Unité de Chimie Environnementale et Interactions sur le Vivant, SFR Condorcet FR CNRS 3417, Université du Littoral Côte d'Opale, Dunkerque, France.
2 Centre Commun de Mesure, Université du Littoral Côte d'Opale, Dunkerque, France.
3 UCEIV – EA4492, Unité de Chimie Environnementale et Interactions sur le Vivant, SFR Condorcet FR CNRS 3417, Université du Littoral Côte d'Opale, Dunkerque, France.. Electronic address: dominique.courcot@univ-littoral.fr.
BEAS-2B cells were exposed using an Air-Liquid Interface (ALI) System (Vitrocell®) to gaseous flows of toluene vapors and outflow after catalytic oxidation of toluene. After exposure to gaseous flow, cytotoxicity, inflammatory response and Xenobiotic Metabolism Enzymes (XME) gene expression were investigated.
Highlights
• Toxicity of toluene increases with time when cells are repeatedly exposed.
• Toxicological analysis helps for validation of catalysts used in treatment of VOCs.
• Cellular response supports the identification of chemically undetected by-products.
Abstract
Toxicity of toluene and by-products formed during its catalytic oxidative degradation was studied in human bronchial BEAS-2B cells repeatedly exposed. BEAS-2B cells were exposed using an Air-Liquid Interface (ALI) System (Vitrocell®) for 1 h per day during 1, 3 or 5 days to gaseous flows: toluene vapors (100 and 1000 ppm) and outflow after catalytic oxidation of toluene (10 and 100%). After exposure to gaseous flow, cytotoxicity, inflammatory response and Xenobiotic Metabolism Enzymes (XME) gene expression were investigated. No significant cytotoxicity was found after 5 days for every condition of exposure. After cells exposure to catalytic oxidation flow, IL-6 level increased no significantly in a time- and dose-dependent way, while an inverted U-shaped profile of IL-8 secretion was observed. XME genes induction, notably CYP2E1 and CYP2F1 results were in line with the presence of unconverted toluene and benzene formed as a by-product, detected by analytical methods. Exposure to pure toluene also demonstrated the activation of these XMEs involved in its metabolism. Repeated exposure permits to show CYP1A1, CYP1B1 and CY2S1 expression, probably related to the formation of other by-products, as PAHs, not detected by standard analytical methods used for the development of catalysts.
