Sulfate concentrations can produce a salty taste in tap water. Sulfates, such as magnesium sulfate and sodium sulfate, can have a laxative effect for persons who are not acclimated to the water and produce hard scales in boilers and water heaters. Sulfates are not easily removed from water, however using an alternate water source or blending sources produces acceptable remedies for sulfate in drinking water. The only observed health effects above 500 mg/L has been the induction of diarrhea. EPA has set a non-enforceable secondary maximum contaminant level for sulfate of 250 mg/L to prevent most taste effects and prevent laxative effects in even the most sensitive consumers (Manual of Small Public Water Supply Systems, EPA570-9-91-003; May 1991).

To help determine the cause(s) of aesthetic or cosmetic effects from your drinking water, contact your local drinking water system. Additional guidance for household well owners is available at www.epa.gov/safewater/privatewells. General information on nuisance chemicals is available at www.epa.gov/safewater/consumer/2ndstandards.html.