According to research carried out by the University of Cincinnati (UC), polycarbonate plastic bottles release harmful chemicals like Bisphenol A (BPA) after having contact with the hot liquid. The amount of Bisphenol A released in the surroundings does not depend on the age of plastic but purely depends on the temperature of the liquid.
Researcher Scott Belcher, UC associate lecturer of pharmacology and cell biophysics and rest of the team found that when plastic (polycarbonate) bottles are exposed to extremely hot temperatures, like boiling water; it releases Bisphenol A 55 times more than the scenario when the bottles are exposed to hot water irrespective of the age of bottles.
The findings of the research paper “Bisphenol A is released from polycarbonate drinking bottles and mimics the neurotoxic actions of estrogen in developing cerebellar neurons” were funded by the National Institute of Environmental Health Sciences grant.
Belcher, Ph.D. and study author explains, “Previous studies have shown that if you repeatedly scrub, dish-wash and boil polycarbonate baby bottles, they release BPA. That tells us that BPA can migrate from various polycarbonate plastics. But we wanted to know if ‘normal’ use caused the increased release from something that we all use, and to identify what was the most important factor that impacts release.”
“Inspired by questions from the climbing community, we went directly to tests based on how consumers use these plastic water bottles and showed that the only big difference in exposure levels revolved around liquid temperature: Bottles used for up to nine years released the same amount of BPA as new bottles.”
Bisphenol A is classified as an environmental estrogen (a substance present in the environment which acts like estrogen when absorbed in the human body). In simple words, it is a synthetic chemical which plays its role as an endocrine disruptor.
Bisphenol A may perform its function by bringing harmful changes in the endocrine system by acting like the body’s naturally produced hormones. Hormones are chemical compounds which travel through the blood and secreted by endocrine glands. They are specific in their functions.
Many studies carried out in animals shows that chemical used in water pipes, plastic bottles, the lining of food cans and in dental purposes may pose harmful effects to the reproductive and nervous system.
Belcher says, “There is a large body of scientific evidence demonstrating the harmful effects of very small amounts of BPA in laboratory and animal studies, but little clinical evidence related to humans. There is a very strong suspicion in the scientific community, however, that this chemical has harmful effects on humans.”
Belcher and his team to get the answer to their hypothesis bought new bottles of a brand and picked up the used ones from a climbing gym of the same company. The bottles were then treated for 7 days following the normal usage for backpacking, hiking, and other outdoor activities.
What UC researchers found was surprising, a similar amount of Bisphenol A was released from the new and old polycarbonate bottles. It was not just the amount which was similar; the rate of formation of Bisphenol A was also the same in a cooler or moderate temperature.
Another thing which amazed the researchers was the large amount of Bisphenol A getting released after it got exposed to boiling water. Belcher says, “Compared to the rate of release from the same bottle, the speed of release was 15 to 55 times faster.”
The rate of production of Bisphenol A in moderate temperature of the water was 0.2 to 0.8 nanograms an hour while in hot water it rose to 8 to 32 nanograms in an hour.
Belcher asserts that they are still not aware of the amount of Bisphenol A which is harmful to the human body. He has now forced people to think about the harmful effects it can pose on the human body.
He explains, “BPA is just one of many estrogen-like chemicals people are exposed to, and scientists are still trying to figure out how these endocrine disruptors–including natural phytoestrogens from soy — are often considered healthy — collectively impact human health. But a growing body of scientific evidence suggests it might be at the cost of your health.”