Okunoshima (132.992E 34.308N), a tiny island in the Inland Sea, was the location of the principal Japanese chemical weapons research and production center. The island was appropriated by the Japanese Army in August 1927 and production began in May 1929. Five types of poison gas were manufactured here, including mustard and diphenylchlorarsine (sneezing gas.) At its peak, in 1937-1944, the arsenal employed 6000 persons, and monthly production capacity was 200 tons of mustard gas, 5 tons of lewisite, 80 tons of diphenylcyanoarsine, 50 tons of hydrocyanic acid, and 2.5 tons of chloroacetophenone.

The island is now known as Rabbit Island (Usagi Jima)  for its large population of extremely tame feral rabbits. This has, improbably, made it a significant tourist destination.


Cook and Cook (1992)

Grunden (2005)

The Japan Times Online, 2005-8-11 (accessed 2008-6-19)

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