According to ScienceDirect_(2005), there was a chemical weapon terrorist attack in Tokyo, named Tokyo Subway Sarin Attack. In the bar chart, it shows how many people were influenced in this event. This figure presents that much more people were influenced than total deaths. In the people who were injured, only few people were serious and other had vision problems. And all of these people were affected their health by Sarin.

          Sarin can be absorbed through the skin, inhalation, and eye exposure. After entering the human body, Sarin would inhibit acetylcholinesterase and then cause muscles paralysis. Finally, the muscles of respiratory tract don’t operate and the people die. Even the low dose Sarin could lead to vision deterioration, headache, nausea, vomit, difficulty breathing, and so on. Fortunately, in Tokyo Subway Sarin Attack, the terrorists use the inferior Sarin, so the number of deaths was not a large amount. In spite of this, the casualty was still considerable.