In 1960, theShiohama-Rengou-Jichikai (an organization of all residents' associations in the Shiohama district)petitioned Yokkaichi City to make improvements because residents were unable to sleep at night due to noise and air pollution. This was the first instance in Yokkaichi of residents demanding action against air pollution.
Air pollution surveys conducted thereafter showed high concentrations of sulfur dioxide (SO2)in the air, particularly in the Shiohama district, and that the airpollution had spread over a wide area towards the northwest.