BPA, or bisphenol A, is a chemical found in the lining of metal cans, polycarbonate bottles and dentistry composites, that has been linked to various health issues, including diabetes, cardiovascular diseases, and obesity.
Take a look at this recent report that shows an alarming increase in BPA level in the body after consuming canned soups.
http://www.naturalnews.com/034811_BPA_canned_food_soup.html
