Sometimes labeled Permanent Orange, unfortunately it is not permanent at all, and has moderate lightfastness. It's currently offered in oils by two paintmakers. Sometimes the blue wool ratings show fading as bad as 4 in tints, and even the better versions are still looking at 5's and 6's.
This article mentions its opacity and weatherfastness, but apparently the weatherfastness does not translate to high enough lightfastness ratings for serious artwork.
As far as health impacts, in her latest work, found via her site Monona Rossol mentions that this is listed as a carcinogen and also has toxic impurities.
