Plastic Bottle Education
Plastic bottles were uncommon until the late 1940's. They remained expensive until the invention of high density polyethylene in the 1960's. Popularity then zoomed among both the manufacturers and consumers because plastics were light in weight and cheaper to make.
The controversy about plastic safety is eternal, not only because of health issues, but also because of environmental concerns. Here's what we need to know. Note that it's not a good idea to refill any plastic bottle, especially with chlorine laden tap water.
PET polyethylene terephthalate is really a misnomer because it does not contain polyethylene. It really doesn't contain phthalates, either. It's used in soft drink, water, and salad dressing bottles, and in peanut butter, pickle, and jelly jars. Only about 30% of the planet's PET is used for bottles; most is used to make synthetic fibers. The antimony used as a catalytic agent in PET's manufacture can leach into the contents if exposed to extremely high heat or to the microwave. Rating: GOOD not known to leach chemicals suspected of carcinogenesis or hormone disruption.
HDPE high density polyethylene is used in milk, water, and juice bottles, in yogurt and margarine containers, and in grocery and trash bags; occasionally in toiletries and water pipes. Rating: GOOD not known to leach harmful chemicals into the contents.
PVC polyvinyl chloride is found in plastic cling films (from the deli, for example), occasionally in juice bottles, in water and sewer pipes, and if unplasticized, in vinyl siding. Traces of the plasticizers, most often phthalates, leach into the foods. Rating: BAD plasticizers (phthalates) can disrupt normal hormone function and possibly cause cancer.
LDPE low-density polyethylene is used to make frozen food bags (the low-density is bendable), squeeze bottles for honey and mustard, cling films, and flexible lids. Rating: O. K. it doesn’t leach anything, but is difficult to recycle.
PP polypropylene may be found in reusable microwave containers, in kitchenware, yogurt and margarine tubs, some ketchup bottles, and Legos. Because it's resistant to fatigue, it's used to make hinges on flip-top lids. Rating: O. K. its manufacture is somewhat hazardous, but it doesn't leach any cancer causing or hormone disrupting chemicals.
PS polystyrene is commonly found in egg cartons, packing peanuts, disposable cups, plates and trays, and some cutlery. It's one of the most widely used plastics. Foam insulation is made from PS. Rating: BAD because it is made from suspected carcinogenic substances and may be neurotoxic, despite its approval for food use. Never put any acidic beverage into a Styrofoam cup. Wine may dissolve it, and fats may absorb it. That means using no cream in coffee.
Other means polycarbonate, ABS, or BPA, none of which should be used for food contact. It has been used to make baby bottles, water bottles, eating utensils, and linings for metal cans. It may also appear inside juice boxes. It was invented in the 1930's in the search for synthetic estrogens. It is a hormone disrupter that simulates the physiological activity of estrogen. It will leach into the contents. Rating: BAD because it also affects neurological function, weight management, infant development and behavior, dopaminergic systems, thyroid hormone receptors, prostate function, and DNA methylation.
That PET has the term terephthalate is misleading. Terephthalate is not the same thing as phthalate. The former comes from terephthalic acid, chemical formula C6H4(COOH)2. The latter comes from phthalic acid, formula C6H4(CO2H)2. The chemical difference is easily seen.
The American Chemistry Council asserts that phthalates are not used to make beverage bottles or any other type of plastic food-contact product. Phthalates, or rather orthophthalates, are used to make PVC flexible, as found in shower curtains and vinyl flooring.
(Enneking, 2006) A concern about PET is the leaching of antimony, a catalyst in PET manufacture, into the contents of the bottle. Any residue can be removed by washing. Some remains in the material, being released if heated.