What you may have heard
Warnings have been posted about cancer risks from drinking from plastic water bottles.
What science tells us
There has been concern of cancer risks from potential exposure to diethylhexyl adipate (DEHA), diethylhexyl phthalate (DEHP), or bisphenol A (BPA) that may be found in plastic water bottles.
The American Cancer Society has stated that viral messages warning against the use of plastic water bottles were not based on peer-reviewed research (ACS). In addition, the Environmental Protection Agency stated that DEHA “cannot reasonably be anticipated to cause cancer; immunotoxicity; gene mutations; liver, kidney, reproductive or developmental toxicity; or other serious or irreversible chronic health effects” (JNCI).
According to the Cancer Research Center in the UK, there have been several studies stating that the chemicals found in plastic are safe to drink since the levels of exposure are very low (Cancer Research UK).
Laboratory Evidence/Supporting Evidence
Researchers examined 10 common brands of bottled water stored under different conditions. They concluded that temperature and sunlight exposure do play a role in degradation of phthalates over time, with freezing temperatures containing higher levels of DEHP. However, DEHP levels in the samples (between 0.296 and 1.778 mg/kg/day) were far below the EPA’s maximum safe dose of 20 mg/kg/day (Al-Saleh et al.). BPA is an industrial chemical that has been used to make plastic since the 1960s. These plastics are frequently used to make containers that store food and beverages. Based on animal studies, BPA exposure at high doses (more than 100 times the level designated safe by the FDA) is likely to cause negative health effects in the kidney and the liver. But the U.S. Food and Drug Administration (FDA) has declared that BPA is safe at the very low levels that may result from water bottle use (FDA). This is based on a review of hundreds of studies (many of which test even heating the plastic for hours at a time), but the FDA continues to monitor this research (JNCI).
IARC Carcinogen Classification: Group 3 (not classifiable as to its carcinogenicity to humans: Bisphenol A diglycidyl ether (Araldite))
How to reduce your risk
The FDA, the regulatory food safety body, reported that BPA, DEHP, and DEHA pose no risk to human health from foodstuffs because current levels of exposure are well below the tolerable daily intake (FDA). However, if you are concerned about BPA exposure, choose stainless steel or glass water bottles instead. In addition, some, though not all, plastics marked with recycle codes 3 or 7 may be made with BPA.
There is not enough evidence to suggest that plastic water bottles cause cancer. However, not all plastic water bottles have the same chemical composition, and ongoing studies about exposure to specific components of water bottles are ongoing.
Learn More From These Trusted Sources
European Food Safety Authority Commission (EFSA): Safety of bisphenol A
Cancer Research UK: Plastic and cancer
Fillon. Getting It Right: BPA and the Difficulty Proving Environmental Cancer Risks
American Cancer Society (ACS): Water bottle myths
Food & Drug Administration (FDA): BPA and food contact
Al-Saleh et al. Phthalate Residues in Plastic Bottled Waters
Published: June 1, 2021
Verified/updated: August 22, 2022