>4.75 nanograms may not seem like a lot, but when you consider that, at 414.07g/mol it is 6,908,293,060,000 parts of the stuff, it seems like quite a bit to me.

This doesn't prove anything part from molecules being really small. What's more important at what doses do negative health effects materialize.

>And that's in just one cooking session.

I'm not sure about you but 1 hour is an usually long time to be using a frying pan. Unless you're cooking a huge slab of meat, letting anything sit in a 230C degree pan for an hour would result it being burnt/overcooked.

>The EPA drinking water standards, the ones watered down by industry influence, are measured in parts per trillion.

Looking through https://www.epa.gov/ground-water-and-drinking-water/national..., the only one that I can find that's near 1 part per trillion is dioxin, at 0.03 PPT. The rest are well above that. Furthermore, even 1 part per trillion is a high estimate for actual exposure. In addition to being spread out across an hour (3600 seconds), the emissions are also dispersed across the room and vented out. Finally, like I pointed out earlier, what maters more is the toxicity of the compound. Dioxins and PFCAs are both "bad", but it doesn't mean they're equally as toxic. The limit for mercury is orders of magnitude higher at 2 parts per billion.