What Are the Health Risks of Reusing Plastic Water Bottles?

Most plastic water bottles sold in the United States are made of polyethylene terephthalate. Because of its light weight, ability to block oxygen and carbon dioxide, and resistance to shattering, PET is extremely popular for packaging bottled water, as well as for microwave food trays and their accompanying food films. The U.S. Food and Drug Administration has tested PET extensively for safety and has ruled that PET is safe for use in the construction of beverage bottles.

Tests to Determine Health Risks

• Scientific tests performed on PET have measured many aspects of its safety. Chief among those concerns are whether any of the packaging transfers to the food or water it contains, whether any of those transfers endanger human health and whether bacterial contamination occurs with prolonged reuse of water bottles. Transfer can be measured down to a minuscule level, and tests have found that any transfer of plastic compounds is within acceptable levels. The FDA has found PET safe for use and reuse of water bottles.

Risk of Bacterial Infection or Contamination

• As long as consumers clean their water bottles in between uses as they would other drinking glasses or containers, there is no greater risk of contamination by transfer or bacterial infection with PET bottles than with other plastic bottles and containers. However, manufacturers usually make bottles specifically intended for extended reuse, as opposed to single-use containers, in such a way that they can be easily cleaned. The FDA performed tests that simulate long-term storage and repeated use of PET containers and suggested that regularly consuming beverages from them probably does not pose any health threat.

Risk From Freezing or Heating

• According to the FDA, there is no scientific evidence to support the theory that PET bottles will release dioxin when frozen. This is because dioxins are only produced at temperatures above 700 degrees Fahrenheit. In addition, according to Mayo Clinic nutritionist Katherine Zeratsky, R.D., L.D., microwave heating of food in plastic containers has not been found to release dioxins into the food.