Home Depot as well as other places still sell it because there isn't
anything much better.

The wood is not dangerous as long as you know how to handle it.
(sort of like many things)

Cutting the wood is the most dangerous part. You need to do
it outside with a good miter saw. Doing it in the house is where
cutting it over and over it'll get into your lungs. Over time you
can have a problem.

If you want to paint it, make sure you let it bake a little outside.
The wood from Home Depot is pretty green and wet. Install it
and wait a week. Make sure that the wood is nice and dry
before you paint it. As for painting it, best bet is to go to your
local Benjaman Moore store and see what type of recommend
outdoor paint to use.