Gulf War veterans have reported a host of symptoms that could be construed as coming from exposure to chemical or biological weapons. The scientific literature on the effects of exposure to such agents suggests: Militarily effective doses of any of the agents reviewed would've produced severe health effects that would've required clinical treatment or resulted in death. However, since low-level exposures could've produced mild clinical signs that could've been overlooked or misinterpreted, it's not possible to rule out low-dose exposures to one or several classes of agents or the possibility of some resultant contribution to some of the symptoms Gulf War veterans have experienced. Still, it's difficult to believe that exposures affecting large numbers of persons would escape clinical recognition. Further, no references in the literature report clinical symptoms developing years after exposure, as was the case in about 50 percent of the health problems Gulf War veterans have reported. Read Less