BTW, I strongly suspect Ken had, in fact, "tested" everything you mention. But that was back, that was back, that was back in the USSR.
There's no reason to "suspect" or guess. This is a claim that can be verified true or false with a readily repeatable test.
Without such a test being made public, there is no reason to believe it, however. It's just too easy to test to see if true or not. I question any such claim that isn't backed by such a simple, public test.