Hi jjj,
Advertising laws in those days were quite relaxed. They may not have even conducted the test. If they did, the radiation level would be quite low and not all that harmful. Even the early "glow in the dark" watches had easily detectable radiation levels. Spread some of that dust on a persons face would do much the same. Very little.
By no means it was anywhere near as dangerous as the nuclear tests they did on the military in the Australian Outback in the '50s. Those were very hushed after the tragic results.
However, the test, I would not be surprised, was conducted in a biased way to favour the promotion of the product. There used to be some really dodgey advertising then. We now have a lot of legislation in place that makes unsubstatiated claims illegal.
Still its an interesting method of convincing the customer.
Do you eat sleep and work with your computer jjj?
You have a lot of input to these forums.
Cheers Marty