There was an old mine in the Toroku district in Miyazaki Prefecture, where the yields were arsenic, lead, tin, zinc etc. Arsenic ore had been mined and refined until 1962.
The miners suffered from verious diseases caused by occupational hazards, because they were assumed to have worked under very poor and deleterious conditions. The residents living in the vicinity of the mine likewise suffered through the ecological cycle caused by the environmental contamination: water pollution, contamination of crops and other products.
After mass examination provided by the Prefectural Government in 1974, the National Government recognized the district officially as “polluted district by arsenic” and the forty-eight persons who had air and worked or lived there as “the patients with chronic arsenic poisoning”.
Many residents have, however, protested against this Governmental conclusion as insufficient, because the poisoning was diagnosed simplly from the limited symptoms such as nasal perforation, skin eruption and pigmentation, and several other severe symptoms were excluded.
The authors performed an epidemiological survey including medical examination of 104 persons, 37 males and 67 females, in October 1974. The residents of the area near the Toroku district were examined and used as controls.
The results were as follows:
1) Many persons among the residents of the district had complaints such as headache, general fatigue, sleeplessness, emaciation, disturbance of vision, conjunctival hyperemia, epihora, nasal hypersecretion, huskiness, cough, sputum, wheeze, palpitation, abdominal pain, low back pain, stiffness on their shoulders, myalgia in their upper limb and so on. Arsenic eruption and hypoesthesia of their extremities were also observed.
2) The authors suggested that health hazards mentioned above were not caused only by arsenic but also by sulfer oxide and other metals such as lead, zinc and tin.
3) The authors pointed out that the measures by the central and local governments were not sufficient to provide medical and health care for the sufferers in that district.
