Miosis nerve agent-induced

For an exposed military population, the dose of a CWA considered to be "low-level" is the lowest dose that results in either an immediate observable adverse health effect or which causes operationally relevant performance decrements. The most sensitive marker of an observable health effect and the purported cause of early significant performance degradation is nerve agent-induced miosis. While various exposure durations can be considered in the planning of future research, a one-time exposure or continuous exposures lasting from minutes to several hours should be the primary target duration of exposure. 

Low dose is sometimes defined in terms of exposure to levels of nerve agent that are described as asymptomatic in that they do not induce overt acute signs or symptoms. While this chapter will focus primarily on the potential effects of such asymptomatic exposures, levels of nerve agent that induce miosis and those which result in transitory disruption of behaviour with minor clinical signs will also be considered. 

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