Zinc Sulfate [CAS # 7446-19-7 / 7733-02-0 / 7746-20-0] = This is an inorganic salt. It's an Antimicrobial. This is a component of our Algae. It is not in the family of sulfates that are detergents which IN does not use. Sometimes INCI (regulatory) names of ingredients can be confusing to a consumer who does not understand the chemistry.