To start to answer your question this wikipedia page lists a vast amount of unethical US experiments. Many are performed, funded, or supervised by a department of the US Military or Agency. It isn't listed by year but there are plenty during the war period. These experiments usually were preformed on mental patients, prisoners, blacks, and children, it included infecting them with illnesses such as malaria, influenza, and syphillis. Also the use of mustard gas and radioactive material that was injected unwittingly into people. Alot of the instances listed were following the war during the cold war but it does list ones during WW2.

There is also the eugenics program in the US that started in the late 1800s but was happening up till and during WW2. Some states still had operating eugenics commitees until far after the war such as North Carolina having a eugenics program until 1977.