PFAS chemicals are widely used for waterproofing fabrics. The industry term is DWR -- Durable Water Repellent. The chemicals are sprayed onto the surface and simply left there to rub off on your hands and face every time you touch them. The chemicals are ubiquitous; nearly every garment marketed as "water resistant" will be covered with them. As of 2019, only one large outdoor clothing company has abandoned PFC-based DWR finishes. I've also noticed more and more furniture advertised with DWR recently.
All of this concern over parts-per-trillion levels in drinking water is like panicking over an untended candle when your house is already on fire.
EDIT:
Also note that the U.S. military regularly dumps tremendous quantities of PFAS chemicals on the ground around dozens of military bases around the country [1]. They use it in fire suppression foam, of which they spray thousands of gallons during regular fire fighting exercises.
There are low-cost and low-toxicity alternatives to PFAS that are fairly well proven to be just as effective in fire suppression foams, but the U.S. military continues to ignore them steadfastly.
1 - https://theintercept.com/2018/02/10/firefighting-foam-afff-p...
EDIT 2:
Don't forget carpeting! For decades, rugs and carpeting advertised as "stain repellent" have been coated with PFCs. One prominent brand is 3M's Scotchgard, which is also sold as a liquid for people to spray on all their shit. Until 2003, liquid Scotchgard contained PFOS, a C8-class PFC that is now banned. Even today, Scotchgard and other similar products still contain PFCs -- merely shorter-chain versions that have been surmised (but not proven) to be safer.