Sadly Skip by us there is a massive mill that processes pine mostly. It is common for the ignorant to buy pine 'bedding' (they sell it as such) from them. It is in huge outdoor mounds and is a come and take as much as you can place (I got some for a woods trail, a pickup truck full and a light trailer cost us 50$). In my area it is common to see it as animal bedding (they sell it on kijiji) and it is fully unprocessed (if it is really cheap it should be investigated). I always leave the caveat, kiln dried, most bags of proper bedding state it is on the bag, it only takes 2 seconds to check. Raw wood of any type is probably not a good idea, phenols aside, it often has a grab bag of insect hitchhikers as well.

I think most agree that phenols are not a good idea and cedar chips are high in phenols, few would debate they are poor choice. I think that it can be simplified by saying phenol rich sources are a poor product to be used in contact with reptiles. For the most part common beddings used for snakes are low phenol sources. It is likely (almost certain) that particle boards contain many times more phenols than pine does.