Ice made from PFAS-contaminated tap water contains PFAS at concentrations comparable to the source water. As ice melts in beverages, it contributes PFAS to the drink — a widely overlooked exposure pathway that can be addressed through appropriate filtration at the ice-making water source.
PFAS Concentration in Ice
When water freezes, dissolved PFAS molecules are largely excluded from the ice crystal lattice and concentrate in the last-to-freeze liquid. In practice, rapidly formed ice (as in home ice makers) traps PFAS throughout the ice matrix rather than fully excluding it, resulting in ice with PFAS concentrations approximately equal to the source water. As ice melts in a beverage, PFAS dissolves into the drink at concentrations proportional to the ice-to-beverage ratio.
Refrigerator Ice Maker Filtration
Most refrigerator ice makers draw from the same filtered supply as the refrigerator’s water dispenser, running through the refrigerator’s built-in filter. If the refrigerator filter is NSF-certified for PFAS reduction, ice benefits from the same filtration as dispensed water. If the refrigerator filter is not certified for PFAS (as is common for standard replacement filters in many appliance brands), ice carries the same PFAS load as unfiltered tap water.
Countertop and Standalone Ice Makers
Countertop and portable ice makers that draw directly from tap water without any built-in filtration produce ice with the full PFAS concentration of unfiltered tap water. Using pre-filtered water from a certified system to fill countertop ice makers, or installing a certified in-line filter on the water supply line to a standalone ice maker, provides PFAS-free ice from these appliances.