Recent evidence suggests that bisphenol A added to PVC plastic actually leaches more than polycarbonate does. So containers marked with number 3 recycling symbols can also add bisphenol A to your food or drink.
Kristina Parusel, Vancouver: I've read that Bisphenol A is in the non-stick coating on cooking pans (Teflon). Is it in all non-stick coatings, only some, and has it been removed altogether for new pans? Thanks! Kristina
Kapil Khatter: Hello Kristina, I haven't seen any evidence that bisphenol A is used in cookware coatings. You are probably thinking of the perfluorinated chemicals - stain repellants and non-stick chemicals like PFOA and PFOS. These chemicals are of concern as well. Not only do they cause harm in animal studies, they are very persistent and build up in our bodies. I believe that companies are trying to reformulate pans so that less PFOA is released.
Francois Hunter, Canada: Hello Doctor; It would seem that BPA's are lurking everywhere... I had never paid attention before, and was a bit concerned yesterday when I opened the door to our freezer and saw, etched in the plastic of the door, a big triangle with the number '7' in the middle. We store our toddler's food in the freezer... Should we be concerned and get a new refrigerator/freezer ?
Kapil Khatter: Hi Francois, I don't think the plastic in your refrigerator door is going to directly contaminate the food you store. The problem with bisphenol A, as with many other chemicals used to make household products, is that they end up in our indoor air and our house dust. In the case of bisphenol A, the widespread use of the chemical has contaminated house dust. I doubt it is worth getting a new appliance at this point, but limiting the amount of PVC and polycarbonate plastic you buy will help to reduce your overall exposure.
Todd St. Jean, Canada: Our twins will be 3 years old this summer and when they used baby bottles (Avent) containing BPA Health Canada said there was no danger to Canadian families. Now Health Canada considers BPA a danger to human life and health. After being exposed to BPA for 12 to 15 months is the health of our twins in danger?
Kapil Khatter: Hello Todd, It is hard to know how harmful the twins' bisphenol A exposure has been. Remember that bisphenol A exposure poses a risk to health, but it is not a given that they have been harmed.
We really don't know how much bisphenol A contributes to the kinds of effects seen in animals. We are exposed all the time to things that increase our risk of illness: second-hand smoke, pesticide residues, mercury-laden fish. The best we can do as individuals and as a society is to limit those exposures in the future.
Corey Jones, Toronto: Dr. Khatter, From what I've read, I understand that for decades, the allowable level of lead in drinking water has been 10 parts per billion (ppb), and lead is an undisputed toxin with known harmful effects to children and adults alike. We don't seem to be in an uproar about that. Can you explain why levels of 6-8 ppb of bisphenol-A leaching from polycarbonates in conditions optimized for leaching (e.g. heating to 80C) should be such cause for such panic?
Kapil Khatter: Hello Corey, We should be in an uproar about lead. New evidence suggests that even lead exposure below 10 parts per billion (ppb) can be harmful to developing children, affecting intelligence and possible contributing to learning disabilities and attention deficit disorder. Unfortunately, I think the progress we've made getting lead out of gasoline and paint has made us complacent. We really don't know what negative impacts lead in drinking water, consumer products and old house paint are having.
Bisphenol A is important because, like lead, there is evidence of harmful effects at really low levels of exposure, at least in animal studies. Bisphenol A is one of the more widely used human-made chemicals and its use is projected to increase. If it takes an uproar to change that trend, then I think an uproar is what we need.
