<Tr> <Td> Ethyldichloroarsine </Td> <Td> 1918 </Td> <Td> Vesicant </Td> <Td> Central Powers </Td> </Tr> <Tr> <Td> N - Ethylcarbazole 679 </Td> <Td> 1918 </Td> <Td> Irritant </Td> <Td> Central Powers </Td> </Tr> <P> Soldiers who claimed to have been exposed to chemical warfare have often presented with unusual medical conditions which has led to much controversy . The lack of information has left doctors, patients, and their families in the dark in terms of prognosis and treatment . Nerve agents such as sarin, tabun, and soman are believed to have the most significant long - term health effects . Chronic fatigue and memory loss have been reported to last up to three years after exposure . In the years following World War One, there were many conferences held in attempts to abolish the use of chemical weapons all together, such as The Washington Conference (1921--22), Geneva Conference (1923--25) and the World Disarmament Conference (1933). Although the United States was an original signatory of the Geneva Protocol in 1925, the US Senate did not formally ratify it until 1975 . </P> <P> Although the health effects are generally chronic in nature, the exposures were generally acute . A positive correlation has been proven between exposure to mustard agents and skin cancers, other respiratory and skin conditions, leukemia, several eye conditions, bone marrow depression and subsequent immunosuppression, psychological disorders and sexual dysfunction . Chemicals used in the production of chemical weapons have also left residues in the soil where the weapons were used . The chemicals that have been detected can cause cancer and can affect the brain, blood, liver, kidneys and skin . </P>

What were the effects of tear gas in ww1