Re:Carcinogens...
My attitude to diet, disease prevention etc, is just do the best you can. Worrying about everything we eat, drink , breath, bathe in, etc, is going to cause a lot of stress. Stress=disease.
As a pathologist, I can tell you that if you live in a large city, you have the same risk of lung cancer as someone who smokes a pack of cigs a day. What do you do?, stop breathing, move somewhere else, (but where), go around with a gas mask on, or a hazmat suit. The same goes for food, all of us are exposed to some level of carcinogens from food, water etc. The best we can do is eat as good a diet as possible, supplement what we aren't getting from food, and try and live the healthiest way we can. Try and limit your exposure as much as you can practically, AND STOP WORRYING ABOUT EVERYTHING.
What effects one person, does not necessarily effect someone else, if you react badly to soy, or it worries you, stop eating it. If you don't react badly, eat it.
spud