An amazing technology with a negative effect that wouldn't be seen till years later when the people buying (or selling) shoes show signs of cancer? Yeah, that scares me. The idea that "It's OK until shown that it's not" leads to hideous down-the-road effects that can't be undone.

I know. You'd delay xrays for many years and have killed many people because of fear.

The precautionary principle is a killer.

The question aaron695 proposed was "Because an amazing technology was misused a little while changing the world it scares you?"

My answer is yes. That doesn't mean I'd have delayed x-rays used by medical professionals, or any of the myriad technologies that did harm when they first came out. I would, however, be worried about them myself, and would want to make it painfully clear to anyone looking into it that the tech's long term effects are unknown. We've been bitten on this repeatedly, and almost every time it's been a trivial use of an eventually useful tech.