A small amount of chlorine, about 1 to 3 parts per million, is injected into the drinking water as a disinfectant to guard against bacteria and virus contamination. This is standard practice in the water treatment industry and is required by federal and state regulations. It is very easy to remove the chlorine taste and odor from your tap water. Put some water in an open top jar in your refrigerator. The chlorine will dissipate in about a half of a day and you will have pleasant drinking water.