Though water is the healthiest thing anyone can drink, science suggests that drinking from plastic water bottles might not be the best thing for you or the environment.
Here are reasons you should avoid drinking from plastic water bottles as much as you can:
• They can release potentially harmful chemicals into your water. When you expose plastic bottles to heat (such as in a hot car, dishwasher, ultraviolet radiation from the sun or microwaves), the outer layers can break down. In response, plastics marked with recycle codes 3 or 7 can release a chemical called bisphenol A (BPA), while BPA-free plastics can release bisphenol S (BPS). These can contaminate your water, says Dr. Cheryl Watson, a biochemist at the University of Texas Medical Branch in Galveston, who’s done extensive research on human exposure to BPA and BPS.
The problem: When you ingest even small amounts, they mimic oestrogen, which can change the way your endocrine system functions. In humans, exposure has been linked to chronic diseases, including diabetes, asthma, and cancer. Animal studies suggest in utero exposure can ultimately impair development of the brain and immune system of a growing baby, with effects that could be passed down to future generations.
Plastic chemicals might make it harder for you to have a baby. Researchers found that men and women undergoing in-vitro fertilization who had high levels of BPA in their blood, urine, and work environment were less likely to have a successful pregnancy, according to a 2013 review of 91 studies published in Reproductive Toxicology.
The problem: Although more research is needed, the results suggest that when BPA imitates oestrogen, it interferes with different stages of pregnancy, such as fertilization and implantation, says Dr. Sheela Sathyanarayana, adjunct associate professor of environmental and occupational health sciences at the University of Washington.
• Plastic chemicals could raise your risk of heart disease and other circulatory issues. Humans exposed to the highest levels of BPA have an increased risk of heart disease, according to a 2012 study published in Circulation. Researchers think this could be due to BPA’s link to high blood pressure, a risk factor for heart disease. After all, the blood pressure of adults who drank from cans containing BPA rose almost immediately in a small but thorough 2015 study published in Hypertension.
The problem: Since BPA and BPS can mimic oestrogen once they get into your system, and high levels of the hormone increase the production of the blood plasma protein, according to Dr. Sathyanarayana, exposure to these chemicals could also lead to blood clotting and related complications like heart events and stroke.