Yokkaichi is a city with the largest population in Mie Prefecture. This was the location of one of the four big pollution diseases of Japan. This one lasted from the mid 1950s to the early 1970s. The burning of petroleum and crude oil caused large quantities of sulfur oxide, a smog began to cover some quarters of the city resulting in severe cases of chronic obstructive pulmonary disease, chronic bronchitis, pulmonary emphysema, and bronchial asthma. Yokkaichi is an industrial city and faces Ise Bay on the Pacific Ocean side of the Japanese archipelago. During World War II, naval fuel factories were constructed in the southern part of Yokkaichi Harbor, but were destroyed by bombing before they began to operate. In the mid 1950s, a petroleum complex was built and began to operate around the remnant of this facility. The complex included the largest heavy oil-fired power station and refinery in Japan at that time. As this complex used crude oil with a high sulfur content (more than 3%) and did not employ suitable measures for desulfurization, the sulfur dioxide (SO2) emissions caused air pollution with an increased concentration of sulfur oxides, as high as 1 ppm in the polluted areas. By early 1960s, the incidence of respiratory diseases, including bronchial asthma, increased among people living in the vicinity of the complex, and this subsequently became a major health problem in Japan, that was known as Yokkaichi Asthma(Yokkaichi Zensoku, in Japanese). At Isozu, where air pollution was most severe, incidence of asthma reached up to 2.5% of total population in 1964. A series of counter measures based on an area-wide total emission control system were taken since 1972, as a result of a successful lawsuit brought by nine inhabitants of Isozu against six companies in the Yokkaichi Court, for reparations of health damage caused by air pollution. The court case began on 1st September 1967, a favorable verdict was obtained on 24 July 1972. Sulfur oxide air pollution in this region has been afterwards markedly reduced. Deemed as one of the Four Big Pollution Diseases of Japan, Yokaikaichi Asthma was felt in the city for nearly 20 years, after Yokkaichi filled in its coastal lowlands in a successful bid to attract modern industries, especially chemical processing, steel production, and oil refining. In 1959 it began 24-hour operations. Although citizens took pride in the growing industrial complex, it is said that their enthusiasm waned when air pollution and noise pollution created grave human health problems.