they can pass through the placenta. and nobody knows what happened when the minute particles run into the body. that's the concern. >> from somewhere i read it seems the main danger is that it could be a carsino gin. duncan duncan donuts put out a statement saying: seems like dunkin' donuts disagrees whether it's a nanomaterial or not. >> first, i think it's important to know the nano materials are not regulated by the f.d.a. when a company puts them in food, there's no regulation to guide them. there is still - we would disagree with their statement about whether these are nanomaterials or not. the testing that we did, there is a range of materials in titanium dioxide. the question is not how one or another defines the materials, what are the impacts. what do we know about the harm that it could cause if they put into the food. >> that raises the question. do you need to address all the ways we are consuming it. >> we are getting it in medicines, in toothpaste. is the government doing enough. >> i think many believe th