I don't know how they get away with selling MSMA pesticide, but you can still buy it in large or small quantities.
They still sell it to applicators that manage large properties. Problem was that idiots were putting it on their lawns in amounts that would make ants form mandibles out the top of their head.
There is no approved pesticide, herbicide, pre emergent, etc that doesn't carry some cautions other than drowning or squashing the bugs.
I know ^^^ this last sentence is made for jest, but don't beat me up too bad.