Comment by __david__

On the plus side, it's a chemical that was discovered more than a century ago so scientists have accumulated a lot of knowledge about it. So far no studies were able to link it to cancer. It also doesn't significantly build up in the body over time (like heavy metals do). It's 3x heavier than air so it shouldn't spread too far away. The main issue is they want to try to keep it from getting into storm drains or into the ground water.

I've heard from others that it's readily absorbed by water. That's bad in the ground water case, but it seems it might be a positive when trying to clean up a (contained) spill.

It appears to me to have a relatively high lethal dosage (my back of the napkin calculations are saying a 200 pound human would have to orally ingest almost a liter of it to reach the LD50 dosage--but again don't quote me on that number because I am not an expert and could have very easily messed up the math or the concept of a lethal dose).

So, while I agree there might be unknown long term issues, it does appear to be a relatively low probability of that since it seems to be on the less pernicious side.