A new study looks at the possible connection between the increase in food allergies and chemicals found in pesticides and tap water. Scientists found that dichlorophenols - which are pesticides found in both items - are associated with food allergies. They say their research showed the chemicals can weaken food tolerance in some people, leading to a possible food allergy. Purifying water may strip it of bacteria that could be beneficial to our immune systems. The study is found in the December issue of the Annals of Allergy and Asthma.