One of my favourite parts of The Big Fat Surprise was learning about the spontaneous combustion of fast-food-workers' uniforms (before & even after being laundered) since polyunsaturated oils replaced transfats & saturated fats in the fryers. The p-u oils oxidize at frying temperatures and the oil splatters and coats the equipment and their uniforms with gunk. I also worry about the lungs of these poor workers.