Andress, a food safety specialist with the UGA Cooperative Extension.
“The FDA regulates materials and substances used for plastic packaging for water bottles as indirect food additives,” she said. “They assess the migration potential of plastics and the substances with which they are made.”
To minimize risks, she suggests using the right plastics the right way and keeping water bottles sanitized. In the freezer, use plastics designed for freezing. Repeated freezing and thawing of plastic not intended to be used that way could lead to structural breakdown and cause a problem.
Also, Andress discourages repeated use of pre-filled plastic water bottles because they are not intended to last structurally through prolonged re-use. The bottles are not deemed chemically unsafe if used repeatedly, but Andress recommends using plastic bottles only as the manufacturer intended.
If you do use a polycarbonate plastic bottle for water and other liquids, wash the bottle with warm soapy water every day. Use a clean bottle brush to clean in and around the bottle neck. Scrub the lids with a bottle brush, too. Rinse well and allow the bottle and lid to air dry.