Possible hazardous components in dental alginates: Physicochemical properties by a mineralogical and spectroscopic investigation

•Dental alginates are linked to heavy silicotic effects for exposed workers.•Mineralogy, morphology and particle size of two commercial alginates were described.•The presence of cristobalite in the respirable dusts was verified.•Cristobalite forms likely during a thermal treatment of natural diatomite precursor.•The risk assessment in the production of dental alginates can be reconsidered.