That is about the cost of treating for termites. I haven't found any insulations that are totally non-toxic, but by having a well sealed house, the insulation can't contaminate the inside air. I chose fiberglass because of availability and cost. For sensitive people, I don't find cellulose any better than fiberglass from a health standpoint. Insulation seem to be a bigger problem for installers than homeowners, and I always wear a quality, tight fitting mask and long sleeves whenever I work with it.
Worker protection is easy to do.
Remember, you're worth it. This is well sealed behind foil-backed drywall to keep particles and gases from entering the living space. Extra care is taken to seal around electrical boxes, windows, doors, etc. Since combustion gases are a problem for sensitive people, even in extremely small amounts, electric heat was mandatory. It seemed to me more cost effective to use a lot of insulation and baseboard heaters than a more expensive heat pump.