Road salt is NaCl but it's much more coarse than the salt you would put in a grinder for food. They also don't make sure the rocks are out of it if it is mined rather than taken from the sea. Transported in trucks that may not have been cleaned. So safe for consumption? Not likely. But it is just NaCl.

Some places use beet juice. It’s still all gonna be mixed with tire and brake dust.

I wish they’d stick to sand anywhere the snow sticks around for more than a day or two.