Seawater quality improved after the Dokai Bay clean-up in 1972 and implementation of industrial wastewater regulation. Current measures include i) chemical substance monitoring (S02, N02, CO, SPM, NO*, PM2 5, dioxins, benzene and trichloroethylene) at 14 general ambient air-monitoring stations and 5 automobile exhaust gas monitoring stations, and ii) water quality monitoring at environmental reference points (27 river sites, 7 ocean sites and 1 lake site) and general measurement points (5 river sites, 11 ocean sites). National standards limit the legal amount of air pollution and wastewater discharges from industries and businesses in Kitakyushu, and the city has the power to control the implementation of these standards.