Plastic Containers for Food and Water

Why do we continue to eat and drink out of plastic containers, when we have known for 80 years that plastics have hormonal effects in the body? Even health-conscious people often drink their two liters of water per day from a plastic bottle.

Some wildly popular water bottles are made of polycarbonate.

Recent news articles have pointed out public health concerns regarding exposure to a known estrogen-mimicking plastic called bisphenol A, or BPA. In fact, in April 2008, the Canadian Government took strong measures to prevent exposure of infants and the environment to BPA.

While Bisphenol A was first synthesized in 1891, the first evidence of its estrogenicity came from experiments in the 1930’s feeding BPA to ovariectomised rats (Dodds and Lawson 1936, 1938). Another compound invented during that era, diethylstilbestrol, turned out to be more powerful as an estrogen, so bisphenol A was shelved… until polymer chemists discovered that it could be polymerized to form polycarbonate plastic. Unfortunately, the ester bond that links BPA monomers to one another to form a polymer is not stable and hence the polymer decays with time, releasing BPA into materials with which it comes into contact, for example food or water.

Minimizing Exposure to BPA

Bisphenol A migrates into foods and liquids most readily at high temperatures; so keep plastic containers at room temperature or colder. Most plastics also migrate more readily under acidic conditions; so never use plastic to store acidic foods or drinks (soft drinks, coffee, citrus of any kind, vinegar-containing foods, tomatoes, pickles, etc.) All plastics are subject to degradation in the presence of oils and fats; so never use plastic to store fatty foods or drinks (milk, salad dressing, meats, oils, nut butters, shortening, etc.) Plastics degrade with time and become less stable, so throw away your water bottles and plastic food containers after six months. Of course, that just moves the problem out of your kitchen and into the landfill — best to not buy plastic containers in the first place!