In this article the findings of a sociologists named Lisa Martino-Taylor are revealed. The US Military were using chemicals against their own citizens during the cold war, and claiming it was to protect them from the enemy, when in reality it was for an experiment. The spraying of toxic zinc cadmium sulfide took place in three different cities, including St. Louis. City officials were not aware of what was happening, and the documents were classified for many years.
When this was discovered the military insisted the chemical was safe. However, the particles that were being sprayed could possibly have been radioactive. No follow up study about long term health issues on the exposed citizens was done.
Another article, released by the government, says that this specific chemical was used because the particles had similarities with the size of particles that could be used for biological warfare. Cadmium would be the most toxic compound of the mixture, it could cause lung cancer as well as kidney and bone problems. However, the claims are this is only when exposed to high doses over an extended period of time. The actual spraying of these chemicals in the 1960s was over a short periods of time, in low doses.
Harmful or not, US citizens should not unknowingly be exposed to chemicals by their own military. Chemicals can react to certain things unexpectedly and cause irreversible consequences.