The coating you cannot see

PFAS stands for per and polyfluoroalkyl substances, a family of thousands of synthetic chemicals built around an unusually strong bond between carbon and fluorine. That bond explains both why they are useful and why they are a problem.

It makes them excellent at repelling grease and water, which is why they ended up in food packaging. A paper wrapper that holds hot oil for twenty minutes without going soft usually has a coating doing that work, and for decades that coating was often fluorochemical.

The same bond means almost nothing in nature breaks them down. Not soil, not composting, not the human body. They persist and accumulate, which is where the phrase forever chemicals comes from.

Why did the WHO's cancer agency got involved

The health research is large and still developing, and we are a materials company rather than a health authority, so the useful thing to point at is what the health bodies themselves have concluded.

In December 2023, the International Agency for Research on Cancer, part of the WHO, classified PFOA as carcinogenic to humans, its highest category, and PFOS as possibly carcinogenic. Those are two compounds out of thousands, and a hazard classification describes what a substance can do rather than the risk from any single product. But it came from a conservative body, and it shifted the regulatory conversation everywhere.

Food packaging drew particular attention because it sits directly against what people eat, and because the pack does not stop existing after the meal.