Plastic water exposed to heat can be toxic
Don’t drink water from plastic bottles left in a hot place for a long time. Chemicals in plastics, mainly antimony (Sb) and Bisphenol A (BPA) can leach into any liquid in a plastic bottle according to new research, and those chemicals can potentially cause diseases (such as cancer) when consumed, based on other research.
• 16 plastic water bottles were exposed to different temperatures: 39°F (4°C), 77°F (25°C), and 158°F (70°C).
• Levels of BPA and antimony were checked after one, two, and four weeks.
• Antimony concentrations in the water from plastic water-bottles averaged 3.18 ng/L at 39.2°F (4°C), and 6.88ng/L at 77°F (25°C).
• At 158°F (70°C) (about the temperature in a car on a hot summer day), levels of antimony in water increased significantly to 38.5 ng /L.
• Levels of antimony in one of the sixteen water bottles increased to 2604 ng/L.
What does this mean to you?
The surge of plastic as a commodity was highlighted in the 1967 film The Graduate. Do you remember The Graduate, starring a young Dustin Hoffman as Benjamin? There is a scene in this film where Benjamin, a recent college graduate with no well-defined aim in life, is pulled aside by a businessman, Mr. McGuire, where this dialogue takes place:
Mr. McGuire: I just want to say one word to you. Just one word.
Benjamin: Yes, sir.
Mr. McGuire: Are you listening?
Benjamin: Yes, I am.
Mr. McGuire: Plastics.
Benjamin: Exactly how do you mean?
Mr. McGuire: There’s a great future in plastics. Think about it. Will you think about it?
Indeed, plastics is big business. But what is the real price of this cheap material?
Virtually all plastic water bottles are made from polyethylene terephthalate (PET) and typically contain 190–300 mg/kg of antimony. Bottled waters become contaminated during storage due to a release of antimony from PET plastic. Actually, almost all packaged drinks are made from PET plastic. This includes milk, coffee, and acidic juice, among types of food containers.
I am guilty of leaving water bottles in my car, but this past summer I wised up and left them in a cooler filled with ice. And yes, I changed the ice weekly after it melted. The temperature in the car can reach 167°F (75°C) at an ambient temperature of 91°F (33°C) in the summer. This research shows that storing water in plastic bottles at high temperatures may enhance contaminant release into water from PET bottles.
Antimony is classified as a possible carcinogen to humans by the International Agency for Research on Cancer. Long-term exposure to elevated antimony can also lead to increased blood cholesterol and decreased blood sugar.
A guideline value of 20 µg/liter (rounded figure) can be derived from this TDI by assuming a 60-kg adult drinking 2 liters of water per day and allocating 10% of the TDI to drinking-water. It should be noted that this value could be highly conservative because of the nature of the end-points and the large uncertainty factor; further data could result in a lower uncertainty factor.
Bisphenol A (BPA)
BPA in all sixteen bottles rose significantly amount increased at 158 F (70 C) to an average of 23.4/ ng/L.
BPA is a key ingredient in modern plastics found and the inner lining of canned foods, and it may act as hormone disrupter where synthetic chemicals called xenoestrogens (synthetic estrogen) mimic estrogen and attach to estrogen receptors (fooling the body into thinking its estrogen). This process interferes with the normal functioning of hormones. One study in prostate cancer cells showed that very low concentrations of BPA activated the androgen receptor and initiated proliferation of cancer cells, independent of testosterone (Wetherill et al. 2002).
BPA is found in plastics and canned goods. Canned goods of tomato sauce, vegetables and soups may contain the chemical in the inner lining called epoxy resins to avoid corrosion of the metal. Epoxy resins are filled with BPA.
BPA enters the body when, let’s say, a plastic water bottle, is washed, heated or stressed, allowing the chemical to leach into the liquid and then enter the body.
Let’s be real here, I am going to drink water from a plastic bottle at some point. But I will continue to be cautious, as I want to maximally reduce my chances of succumbing to cancer and other life threatening diseases. I think this is a holistic but realistic approach. So, here’s what to do.
• Decrease exposure: Plastic bottles have a recycling code at the bottom of the bottle that looks like a triangular arrow around a number. Avoid these numbers: 3, 6 and 7. Plastics especially with the Number 7 contain BPA.
• Avoid canned foods. They are often void of nutritional value and can have BPA leach into the food. Use glass container to store food. Note: glass containers do not contain BPA chemical but tops used to close glass containers do.
• Avoid purchasing either canned salmon or canned sardines in vinyl-lined cans that contain BPA. We recommend contacting the manufacturers of these products to find out which ones use BPA-free cans. If you cannot find BPA-free cans, you may want to consider purchasing the fish in another (non-canned) form. Vital Choice offers an excellent assortment of wild BPA-free fish and sardines.
• Don’t microwave food or drinks in plastic containers—even if they claim to be “microwave safe.” Heat can break down plastics and release chemical additives into your food and drink. Microwaves heat unevenly, creating hot spots where the plastic is more likely to break down.
• Don’t use plastic containers for hot liquids—only cool liquids if at all.
• Don’t reuse single-use plastics. They can break down and release plastic chemicals when used repeatedly.
• Don’t use old plastic water bottles. Exposures to plastics chemicals may be greater when the surface is worn down.
• The big don’t of course is this: don’t leave water in plastic bottles in your car.
• Wash plastics on the top rack of the dishwasher, farther from the heating element, or by hand. This will reduce wear and tear.
• Bring your own mug for coffee to the office and to your coffee shop, and use that instead.
• Bring drinking water from home in glass water bottles instead of buying bottled water. Or, buy glass bottled water – Mountain Valley Spring Water is an excellent brand.
• Store foods in the freezer in glass mason jars and not in plastic bags.
• Use stainless steel or high-heat-resistant nylon for utensils in lieu of plastics.
Westerhoff, P., Prapaipong, P., Shock, E., Hillaireau, A. (2008). Antimony leaching from polyethylene terephthalate (PET) plastic used for bottled drinking water. Water Res. 42: 551–556.
World Health Organization. Water Sanitation Health: Antimony in drinking water. Accessed 1 October, 2014. http://www.who.int/water_sanitation_health/dwq/chemicals/0304_74/en/index9.html
Fan YY, Zheng JL, Ren JH, Luo J, Cui XY, Ma LQ. (2014). Effects of storage temperature and duration on release of antimony and bisphenol A from polyethylene terephthalate drinking water bottles of China. Environmental Pollution 192:113-20.