Q. Is it true that people should not re-use plastic bottles to store water for disasters?
A. This question is related to the one above. In a Master's Thesis by a student at the University of Idaho, which was not peer reviewed and had questionable scientific validation, the student asserted that certain types of plastic could release certain chemicals which he considered to be potentially carcinogenic. This assertion got widespread media attention last summer. In typical fashion, some media outlets passed on the information without obtaining verification from an independent source. This assertion started flying via email and in web postings from several organizations (but not Red Cross). Some of the public believed the news reports and became frightened, confused, or upset.
A variety of professional organizations and government agencies reviewed the claim, and found it to be untrue. The Food and Drug Administration (FDA), as well as the U.S. Department of Agriculture Food Safety and Inspection Service (USDA FSIS), carefully examined the claim and concluded, through research, that the claim was false. The FDA and USDA FSIS are members of our National Disaster Education Coalition and informed all of us the results of their independent research.
While the water bottling companies would like people to purchase bottled water, what the FDA and USDA FSIS have said is that if people select bottles like plastic soda bottles, and thoroughly clean and sanitize the bottles after use, the bottles can be refilled with tap water and stored for emergency use. Home-stored water should be replaced every six months. They further said that water should NOT be stored in plastic milk jugs. That's because milk has fats in it which get into the plastic, and those fats can not be sufficiently removed or cleaned out, even with bleach or other ordinary cleaning products such as disk soap or dishwashing detergent. Refilling these jugs poses a risk for the residual fats to foster bacterial and algae growth inside the jug. So using these containers to store water is NOT recommended."
FEMA also said: "If you decide to re-use plastic storage containers, choose two-liter plastic soft drink bottles - not plastic jugs or cardboard containers that have had milk or juice in them. The reason is that milk protein or fruit sugars cannot be adequately removed from these containers and provide an environment for bacterial growth when water is stored in them."
http://faculty.deanza.edu/donahuemary/Storewaterforafteranearthquake