Is a chipped off drywall harmful
Drywall regularly cracks / chips where nails and screws are, I don't know of any health hazards and filling voids with "mud" or joint compound is a normal process for sheetrock repair. I have been doing this for 40+ years. The only problems I have heard of were some had caustic ingredients that etched copper pipe the suppliers were from China after Hurricane Katrina? But other than that I know of no problems, yes you should use a dust mask when cutting and sanding but other than this if there was a problem you would be seeing tv advertisements constantly like the ones now showing up for roundup weed killer and asbestos although both are devastating very rare and in the US and sheetrock has been the prominent wall covering for 6 + decades.