1,2-Naphthoquinone is one of the major metabolite of naphthalene, which is responsible for the cytotoxicity and genotoxicity associated with it. 1,2-Naphthoquinone is an atmospheric contaminant. It causes the contraction of trachea smooth muscles in guinea pig through the activation of epidermal growth factor receptor. 1,2-Naphthoquinone has been reported as an environmental quinone in diesel exhaust particles (DEP) and atmospheric particulate matter.