Filtering your water

If levels are concerning, consumers can purchase a water filter for their tap. NSF, formerly the National Sanitation Foundation, has a list of recommended filters.

“The water filters that are most effective for PFAS are reverse osmosis filters, which are more expensive, about in the $200 range,” Andrews said. Reverse osmosis filters can remove a wide range of contaminants, including dissolved solids, by forcing water through various filters.

“Granular activated carbon filters are more common and less expensive but not quite as effective or consistent for PFAS,” he said, “although they too can remove a large number of other contaminants.”

Reverse osmosis systems use both carbon-based filters and reverse osmosis membranes, Andrews explained. Water passes through the carbon filter before entering the membrane.

“The important part is that you have to keep changing those filters,” he said. “If you don’t change that filter, and it becomes saturated, the levels of PFAS in the filtered water can actually be above the levels in the tap water.”

Carbon filters are typically replaced every six months, “while the reverse osmosis filter is replaced on a five-year time frame,” he added. “The cost is relatively comparable