BPA is an xenoestrogen, or estrogen not built by the sun. Soy is a phytoestrogen built by the sun on the other hand. BPA is found in many comonly used plastics, like receipt paper, and is absorbed through the skin when touched. Too much estrogen causes feminine traits in men and masculine traits in women. Excess estrogen is dumped into the large intestine where it binds with fiber and removed. If there is not enough fiber the excess estrogen does not bind to anything and is reabsorbed with the water. Due to poor health choices most children will be sterile by 2045, no vaccine needed.