| Name of Country | Year | CWA | Causalities (Estimated) |
| Germany | 1915-18 | Chlorine, phosgene and Mustard gas | 120,000 |
| Italy | 1936 | Mustard gas | 15,000 |
| Japan (Two Times) | 1937-45 and 1995 | Mustard gas | 2500 |
| America | 1962-1967 | Tear gas and Herbicides | 2000 |
| Afghanistan | 1979-80 | Mustard gas | 2100 |
| Iraq | 1980-88 | Mustard gas | 50,000 |
| Syria (Four Times) | 2013-18 | Sarin gas | 1000 |