The paper describes the initial characterization of neuroblastoma cell lines to address several aspects of organophosphate neurotoxicity. Several commercially available human and mouse cell lines (i.e., SY5Y, IMR-32, SK-N-MC, NB41A3) were evaluated for their target esterase activities (i.e., cholinesterase, neurotoxic esterase, carboxylesterase), and of these cells, a human (SY5Y) and mouse (NB41A3) neuroblastoma cell line clone were used to establish an IC50 cytoxicity profile for a variety of organophosphates insecticides (e.g., parathion, paraoxon, diisopropylphosphorofluoridate and mipafox). The human neuroblastoma cell line clone (SY5Y) was further used to distinguish between neuropathy-causing OPs and cholinesterase inhibitors. These initial data support the use of neuroblastoma cell lines as effective test models for organophosphate neurotoxicity.