Effects of Sarin on the Nervous System in Rescue Team Staff Members and Police Officers 3 Years after the Tokyo Subway Sarin Attack Yuji Nishiwaki,1 Kazuhiko Maekawa,2 Yasutaka Ogawa,3 Nozomu Asukai,4 Masayasu Minami,5 Kazuyuki Omae,1 and the Sarin Health Effects Study Group 1Department of Preventive Medicine and Public Health, School of Medicine, Keio University, Tokyo, Japan; 2Department of Traumatology and Critical Care, Graduate School of Medicine, University of Tokyo, Tokyo, Japan; 3National Institute of Industrial Health, Kawasaki, Japan; 4Department of Social Psychiatry, Tokyo Institute of Psychiatry, Tokyo, Japan; 5Department of Hygiene and Public Health, Nippon Medical School, Tokyo, Japan
Abstract Although the clinical manifestations of acute sarin poisoning have been reported in detail, no comprehensive study of the chronic physical and psychiatric effects of acute sarin poisoning has been carried out. To clarify the chronic effects of sarin on the nervous system, a cross-sectional epidemiologic study was conducted 3 years after the Tokyo subway sarin attack. Subjects consisted of the rescue team staff members and police officers who had worked at the disaster site. Subjects consisted of 56 male exposed subjects and 52 referent subjects matched for age and occupation. A neurobehavioral test, stabilometry, and measurement of vibration perception thresholds were performed, as well as psychometric tests to assess traumatic stress symptoms. The exposed group performed less well in the backward digit span test than the referent group in a dose-effect manner. This result was the same after controlling for possible confounding factors and was independent of traumatic stress symptoms. In other tests of memory function, except for the Benton visual retention test (mean correct answers) , effects related to exposure were also suggested, although they were not statistically significant. In contrast, the dose-effect relationships observed in the neurobehavioral tests (psychomotor function) were unclear. None of the stabilometry and vibration perception threshold parameters had any relation to exposure. Our findings suggest the chronic decline of memory function 2 years and 10 months to 3 years and 9 months after exposure to sarin in the Tokyo subway attack, and further study is needed. Key words: cross-sectional study, neurotoxicity, police officers, rescue workers, sarin. Environ Health Perspect 109:1169-1173 (2001) . [Online 6 November 2001] http://ehpnet1.niehs.nih.gov/docs/2001/109p1169-1173nishiwaki/ abstract.html Address correspondence to Y. Nishiwaki, Department of Preventive Medicine and Public Health, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. Telephone: +81-3-3353-1211 ext 62655. Fax: +81-3-3359-3686. E-mail: nisiwaki@med.keio.ac.jp Members of the Sarin Health Effects Study Group are T. Yamaguchi, M. Hirata, M. Takahashi, M. Katsumata, Y. Sano, A. Imai, R.R. Chin, and T. Saito. We thank the staffs of the Tokyo Fire Department and the Metropolitan Police Department for their support, which made this research possible. This study was partially supported by Health Sciences Research Grants of Ministry of Health and Welfare, Research on Health Services (H10-062) . Received 28 March 2001 ; accepted 14 May 2001. The full version of this article is available for free in HTML or PDF formats. |