7. Project SHAD
The threat of a chemical attack on the U.S. was very real during the Cold War. To prepare for such a blow at sea, the Department of Defense conducted various experiments by spraying biological and chemical agents on several ships from 1962 to 1973.
The program known as Project Shipborne Hazard and Defense (SHAD) was conducted to test decontamination efforts. It involved about 6,000 military personnel. Only some were aware of the tests.
The Pentagon began declassifying details of the experiments following public outcry in 2000. Some of the sailors and marines involved are still struggling to receive benefits from the Department of Veterans Affairs.