Let me ask this: If there were rumors of a bad substance in a product you were selling, don’t you think you’d be racing to a microphone to denounce those rumors?
Well, that depends...
[Most UNSATISFYING response, EVER, I know.]
If the accusers were nutty enough, I very likely might not give them the time of day; I’d just let them publicize their nuttiness until they self-immolated, tip my glass of dry sherry at the CNN anchor, and enjoy a long draw on my cigar.