Death can result from both respiratory and skin exposure.
These agents in vapor form are rapidly absorbed through the respiratory system, and death can result within 1 to 10 minutes. Symptoms appear much more slowly when the dose is acquired by absorption through the skin. CHE is an enzyme which is important in the transmission of nerve impulses to muscles. The effects of repeated exposures can be cumulative, and workers may experience severe CHE depressions from repeated exposure to low concentrations of agent. The rate of regeneration of CHE within the body is slow.