(Baltimore) -- A Montour County doctor is taking part in a study to research the long-term health of a group of veterans who were exposed to biological and chemical toxins during the Cold War. Joseph Boscarino, a senior investigator with Geisinger Health System in Danville, is participating in the SHAD-II project. He'll interview some of the more than 5,000 veterans who were exposed to toxins during the 1960s as part of Project SHAD, or Shipboard Hazard and Defense. Boscarino says the federal government wanted to test the substances on military members, specifically Navy sailors, but didn't believe it would truly harm the troops. "Many of these agents were never used intentionally to cause harm on the veteran," he says. "At the time, whether it was Agent Orange or anthrax vaccinations or, in this case, this experiment, it was done for national defense purposes and to try to protect the troops. It's a part of military service." Boscarino, who's a veteran of the Vietnam War, says the study will begin next year and could take up to two years to complete. A previous study found no long-term effects on veterans' health linked to Project SHAD, but some veterans groups called for more experimentation.