For many people, the largest single volume of tap water consumed daily goes into morning coffee or tea. Understanding PFAS transfer into brewed beverages helps quantify an important but often overlooked exposure pathway for households with contaminated tap water.
PFAS in the Brewing Process
Brewing coffee and tea involves heating water and flowing it through or over plant material, then consuming the resulting liquid. PFAS dissolved in the source water transfers into the brewed beverage essentially proportional to its concentration in the water — there is no mechanism in standard brewing that removes PFAS. A cup of coffee or tea made with water containing 50 ppt PFOA delivers approximately 50 ppt PFOA to the drinker per cup consumed.
Volume Consideration
A coffee drinker consuming three cups daily uses approximately 24 ounces (0.7 liters) of water per day in beverages alone, before accounting for direct drinking water. For households where beverages made from tap water constitute a significant fraction of total water intake, PFAS exposure through this route is proportionally significant.
Coffee Maker and Kettle Considerations
Some modern coffee makers and electric kettles include built-in filtration. Reviewing whether the filtration in any appliance is certified for PFAS reduction is worthwhile, as most built-in appliance filters are designed for taste and odor improvement rather than chemical contaminant reduction. Using pre-filtered water from a certified point-of-use system for brewing provides more reliable PFAS exposure reduction than relying on appliance filtration of uncertain certification status.