Sodium sulfate is a white powder, or crystals. It is used for standardizing dyes, in freezing mixtures, and in dying and printing textiles. It is also used as cathartic and purgative in humans and in veterinary medicine.

Human studies: It may result in gastrointestinal irritation and diarrhea. animal studies: Poultry mortality was 33% after drinking water containing 7500 mg/L sodium sulfate for 15 days. Outbreaks of poisoning in pigs due to overdosage were characterized by twitching, tremors and convulsions. The most noticeable lesion at post mortem was widespread vacuolation and necrosis of cerebral cortex. ecotoxicity studies: Plants were injured by sodium sulfate levels of 4000 mg/L in soil; 710 mg/L depressed root growth and water absorption. Among aquatic species, the cladoceran and mussel were acutely more sensitive to sulfate than the midge and fathead minnow, whereas the fathead minnow was chronically more sensitive than the other 3 species.