Life hack/compromise...

If you must eat fast food, forego all sauces and toppings on your sandwiches that arent protein centric.

No mayo, no ketchup, no special sauce, no pickles, tomatoes or lettuce.

It wont remove all toxins from seed oils and the like but it will reduce them relative to the overall meal. Its a lot less messier to eat as well and makes it easier to put the bread aside.