I would be very concerned at the idea of disposing of the originals unless they really were too dangerous to keep.
1. I would scan them at a high resolution, preferably both sides.
2. I would investigate removing the odor by possibly airing them in a fume cupboard, vacuum treatment, book deodorisers or just putting a batch in a sealed polythene or polypropylene box over a tray of cat litter to absorb the odors. Make sure the papers do not touch the litter.
3. Has the substance been identified ? Is it camphor? Naptha? Are there legal requirements for disposal of this chemical in your area? Some substances like camphor can soften plastics.