1993 年 8 巻 3 号 p. 439-446
The true route of contamination of the Namikata arsenical poisoning incident in Shikoku, which took place in 1933-1935, has remained unclarified, in spite of intensive on-the-spot investigations. The Toroku mine in Miyazaki, Kyushu, had produced arsenicals for scores of years until its complete discontinuance of operations in 1962. The arsenious acid produced there increased between 1921 and 1941, most of which was transferred to Ohkunojima, an islet in Tadanoumichou, Hiroshima Prefecture as materials for lewisite [ (CHCl: CH) 2 AsCl], a poisonous gas, it has been disclosed.
Marine shipping agents in Namikata and nearby towns, well aware of the Inland Sea, transported various things in small boats carrying only 2 to 4 persons, often family members from Kyushu to Osaka and Kobe areas. We assume that this was the route of contamination in the Namikata arsenical poisonig incident because of the following reasons: Most of the patients were young 20 to 30 year-old seamen, most of them were family members, such as a man and his child, man and wife, man and cousins, no aged persons or children had been affected. An episode which was told one of us (Kubo, who has worked in Namikata where the incident took place) was that there was a strong demand of a man that there should be no mention of the death in connection with her job when a 47 aged wife died of lung cance in 1956 and her death certificate was prepared, because it would inform her relatives that poisonous materials had been sent with them.