Matsumoto and Tokyo

According to inpatient records from St Luke s Hospital, the most common laboratory finding related to sarin toxicity was a decrease in plasma cholinesterase (ChE) levels in 74% of patients. In patients with more severe toxicity, plasma ChE levels tended to be lower, but a more accurate indication of ChE inhibition is measurement of erythrocyte ChE, as erythrocyte ChE (AChE) is considered true ChE and plasma ChE is pseudo ChE . However, erythrocyte ChE is not routinely measured, whereas plasma ChE is included in many clinical chemistry panels thus, it can be used as a simple index for ChE activity. In both the Matsumoto and Tokyo subway sarin attacks, plasma ChE served as a useful index of sarin exposure. In 92% of hospitalized patients, plasma ChE levels returned to normal on the following day. In addition, inpatient records from... 

Security aspect. This review of AUM Shinrikyo s terrorist activity reveals a new threat to stability of democratic societies - chemical terrorism. Especially terrifying dimension of the problem is the fact that members of this fanatic cult used nerve gases three times against civilian population - sarin in Matsumoto and Tokyo in June, 1994 and in March, 1995, respectively, and VX in Tokyo in January, 1995. The two sarin attacks were especially dangerous, because they threatened the lives of hundreds of citizens. 

Application of fluoride reactivation to serum samples of casualties of the Matsumoto and Tokyo incidents yielded sarin concentrations in the range 0.2 1.1 ng/ml serum (Polhuijs et al, 1997). Hydrolytic displacement of the phospho-nyl residue identified /PrMPA at levels sufficient for full-scan mass spectra to be obtained from samples collected from casualties who died (Nagao et al, 1997) MPA was also identified. MPA was detected in formalin-fixed brain tissues some two years later using a similar procedure (Matsuda et al, 1998). The phosphonylated peptic nonapeptide from BuChE was identified in serum samples from several casualties of the subway attack (Fidder et al, 2002). 

The release of the nerve gas sarin by the Aum Shinrikyo cult in Matsumoto and Tokyo - in June 1994 and March 1995, respectively (see Chapter 13) - alerted the world to the very real chemical threat from terrorist groups. The determination and sophistication of subsequent terrorist attacks, the access such groups seem to have to the necessary funds, expertise and materials and their avowed intent to cause mass casualties and fatalities all emphasise that the possibility of a deliberate chemical release in a civilian setting can no longer be ignored. 

The Matsumoto and Tokyo subway sarin attacks were wake-up calls to NBC terrorism. These incidents proved that terrorists could actually deploy chemical weapons and weapons of mass destruction. We have previously analyzed and reported on the Tokyo subway sarin attack from the viewpoint of clinical medicine (Okumura el al., 1996,1998a, 1999). Here, by including the findings of the court trials and information related to the attacks that has become available, we review the experiences and lessons learned from the Tokyo subway sarin attack in the hope that doing so will improve measures against chemical terrorism. 

Large amounts of 0-isopropyl methylphosphonic acid were found in blood and nrine of victims of the terrorist attacks with sarin in Matsumoto and Tokyo. Until recently, it was assnmed that hydrolysis of phosphofluoridates in plasma and tissues of mammals proceeds exclusively by cleavage of the P F bond. For example, treatment of C( )P( )- P-soman with rat plasma or liver homogenate did not lead to any conversion of PMPA into the secondary hydrolysis product methylphosphonic acid (MPA). Ramachandran observed that the primary hydrolysis product of DF P, i.e., 0,0-diisopropyl P-phosphoric acid, is not metabolized after s.c. admiiustration to mice. Rather, the product was excreted unchanged into urine. However, Nakajima et al. reported that MPA was detected (in urine) until the third day after hospitalization of a victim of the terrorist attack with sarin in Matsumoto. This discrepancy needs further investigation. 

Prior to plans for the destruction of the CW stockpiles of most countries, and preceding the sarin attacks in Matsumoto and Tokyo, the development and implementation of defensive measures against CW agents was primarily centered on the mihtary use... 

Chemical warfare nerve agents pose a potential threat to the general public as well as the military, as evidenced by several incidents. Between 1980 and 1988, sarin (GB) was used by Iraq in the war with Iran, with the most notable incident occurring in 1988 when a Kurdish city in northern Iraq was bombarded with chemicals, possibly including GB, tabun (GA) and 0-ethyl 5-[2-(diisopropylamino)ethyl] methylphosphonothioate (VX). In 1994 and 1995, the Aum Shinrikyo sect attacked subways in Matsumoto and Tokyo with GB, and also attacked individuals with VX in Osaka and Tokyo. One of these individual attacks resulted in the death of the intended victim. The victim had VX deposited on his neck and exhibited symptoms typical of organo-phosphate poisoning, but confirmation of the nerve agent used could only be achieved after his death with the testimony from one of the suspected attackers and detection of VX metabolites [ethyl methylphosphonic acid (EMPA) and 2-(diisopropylamino-ethyl)methyl sulfide (DAEMS)] in a blood sample taken approximately 1 h after the attack. 

In 1995, there was the first documented use of a CW agent by terrorists in a civil setting with the release of sarin in the Japanese cities of Matsumoto and Tokyo. These incidents again raised public awareness of the vulnerability of unprotected civil populations to toxic agents. These incidents are discussed in more detail in Chap. 10. 

Terrorist Sarin Attacks in Matsumoto and Tokyo, Japan... 

The Matsumoto and Tokyo sarin incidents were the first examples of terrorist attacks in a civil setting using a military nerve agent. The sarin used had been synthesised in a secret laboratory and proved that such syntheses were within the capability of terrorist organisations. 

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