Toluene, a benzene analog, is widely employed as an organic solvent. It has been reported to be a biotoxic solvent (toxic to many microorganisms at 0.1% v/v concentrations). Its anaerobic biodegradation to CO2, by the denitrifying bacterium Thauera arornatica has been reported. It forms syndiotactic polystyrene-toluene molecular compound. Crystal structure of this molecular compound has been investigated by X-ray diffraction studies.