Drywall and other Conventional building questions from a pondering Permie

So brief history lesson about our small homestead. If you dont want a back story skip to next paragraph for questions.  We bought our 1.8 acres around two or less years ago. We bought it for the land and had a pretty beat up house on it that we wanted to tear down and build some thing very permieish. The more we looked at and influenced by some friends and that crazy guy from texas that wants to build a tiny home town in the desert, we desided to fix up the old house instead of tear it down and send a couple tons of perfectly good materials to the land fill. We put a roof on the house, and have been very very very slowly working on it here and there. Over chrismas break we started to demo and get rid of all the molded rotting stuff. We threw out what could not be composted or burned.  We left alot of the drywall in place that did not have water damage but now I am wondering.
Is there any known "indoor pollution" risk using dry wall? I had originally planned to do earthen plaster and still do in the rooms were we do have to do alot of wall repair.  Is drywall that bad I figured by using what is already in the house I am saving waste from the land fill, time, and money. Any thoughts or experience in this area? I have more conventional house questions but this is the most pressing at the time.  

If the drywall didn't have water damage and you don't see tiny black specks of mold (the notorious black mold) growing on it, it may be safe to use. Tiny black specks will grow into very large spots and can cause serious health issues if moisture conditions are high enough and the spores get airborne and people breathe them. The other problem with drywall is the fire retardant chemicals added to it during manufacturing which can contribute to "indoor pollution". Some are bigger offenders than others. They make a commercial "fire grade" drywall, which I believe gets it rating from it being thicker than standard residential sheetrock, but chemical levels may be different as well. Generally those chemical VOC's (volatile organic compounds) subside with a couple coats of paint, and time. They do have VOC absorbing paints on the market which help with removing those from the air. Toxic VOC's are difficult to avoid nowadays, but it's possible. Major offenders are carpet, upholstered furniture, mattresses.... Most contain fire retardant chemicals, but some manufacturers are now omitting the fire retardants because it's been proven that they don't really work or slow a house fire and they do make people very sick. Other kinds of VOC's can come from things like traditional oil based polyurethane varnish on hardwood floors and furniture. They now make zero VOC varnishes, paints and stains. Some individuals are more sensitive to VOC's than others.

Sorry I veered a little off topic there. So, indoor pollution risk? yeah maybe, depending on who you ask. The drywall may be the least of your concerns. Was the house built prior to the 1970's? Those older coats of paint further down may contain lead, which is safe as long as that paint stays in place and no one takes sandpaper to it or flakes don't fall off the ceiling into your soup. Built in the 1950's or before? Maybe some asbestos hanging around somewhere? I certainly don't want to scare you with lead paint and asbestos, all I want to do is help and offer advice. Maybe just pitch the sheetrock, be done with it and earthen plaster everything

Hey James thanks for the speedy response I'll check the build date. And thanks for veering off these are all question I am working towards as well.