Researchers are continually finding new evidence that common items in our kitchens, bathrooms and toy chests can make us sick. One of the most insidious substances is bisphenol A, a component of the light plastics used in baby bottles and many other consumer products. Over the past several years, scientists have reported that low levels of bisphenol A can disrupt cell division, leading to spontaneous miscarriages and birth defects such as Down syndrome.