Are BPA-Free Containers Really BPA-Free?

The presence of bisphenol A (BPA) in food and beverage containers is increasingly controversial. While the food industry maintains levels of the chemical are safe, they are looking into alternatives.

Among the BPA-free materials being used in alternative containers are stainless steel and coated aluminum. Researchers at the University of Cincinnati (UC) have studied them to determine if they truly are free of BPA.

Scott Belcher, PhD, associate professor in the UC pharmacology and cell biophysics department, and colleagues found that stainless steel- and/or co-polyester lined-aluminum bottles did not release BPA. However, aluminum bottles lined with epoxy-based resins still resulted in BPA contamination of liquids.

"BPA is an ever-present, high-volume industrial chemical that is an estrogen and an environmental endocrine disrupting chemical,” said Belcher, adding that it has been shown in experimental models to negatively impact the heart and reproductive system and enhance the growth of certain tumors.

"It is used extensively in the production of consumer goods, polycarbonate plastics, in epoxy resins that are used to coat metallic food and beverage cans and in other products. There is great concern regarding the possible harmful effects from exposures that result from BPA leaching into foods and beverages from packaging or storage containers.”

The tests

Belcher said the objective of the study was to independently assess whether BPA contamination of water was occurring from different types of reusable drinking bottles marketed as alternatives to BPA-containing polycarbonate plastics. He said all reusable bottles used in the study were obtained from retail sources and were constructed from polycarbonate, co-polyester, stainless steel, aluminum with co-polyester lining or aluminum with epoxy resin lining.

They were put through a number of tests, including filling them with boiling water.

"Results once again showed that, at room temperature, detectable concentrations of BPA migrated from polycarbonate bottles. This confirmed our lab’s previous study,” said Belcher. "However, under the same conditions, BPA migration from aluminum bottles lined with epoxy-based resins was variable depending on the manufacturer. The discount store branded bottles tested released much more BPA.”

Boiling water increases BPA levels

He says boiling water significantly increased BPA migration from the epoxy-lined bottles. No detectable contamination was observed in water stored in bottles made from co-polyester plastic, uncoated stainless steel or aluminum lined with EcoCare.

"The results from this study show that when used according to manufacturers’ recommendations, reusable water bottles constructed from ‘BPA-free’ alternative materials are suitable for consumption of beverages without the fear of BPA contamination,” Belcher says. "BPA does, however, migrate into water stored in polycarbonate plastic and metal bottles coated with epoxy-resins, especially when heated to high temperatures.”

The take home message, he says is that consumers should not think that just because a bottle isn’t polycarbonate plastic that it is safe from the dangers of BPA, but while there are no standards for claims of ‘BPA-free,’ it appears that ‘BPA-free’ labels used to market co-polyester-based water bottle alternatives actually reflect a lack of BPA contamination in liquids stored in those containers.

"While consumers have been skeptical of manufacturers’ claims, these studies confirm that these specific products do offer a BPA-free alternative to polycarbonate or epoxy lined bottles and that companies have responded to their consumers’ desires for BPA-free products,” he said.