I think it's a non-issue. When you do the math there's very little product left in the carpet. Especially when you padcap. And, as I mentioned, in 20 plus years I haven't seen or heard of any reason for concern. I'll give the formulators the benefit of the doubt they're not using carcinogenic polymers. lol
When you say "The risk of encap dust is also a none issue.......", though, it's meant to cast doubt on competitive products, some of which I'm rather fond of. I'm not trying to bust your chops but I do think it's only fair you quantify the "risk of encap dust" before you start beatin' up the competition. It's not just a question of it becoming airborne, it's a question toxicity. That's the sorta thing qualified labs test on rats, not with simple in-house factory tests.