Know Your Plastics

The numbers on plastic bottles actually refer to the type of plastic, not just the recycling method. Plastics 1, 2, and 4 are the easiest to recycle. Plastics 2, 4 and 5 are the least toxic. Stay away from plastics 3, 6, and 7 as much as you can.

#1: Polyethylene Terephthalate (PET). Often used for soft-drink and single-use water bottles. May leak antimony, a heavy metal.

#2 High density polyethylene (HDPE). Often used in opaque detergent bottles, juice bottles, hard plastic milk jugs and some plastic grocer bags.

#3: Polyvinyl chloride, or PVC. The problems with this plastic are that dioxins are produced during manufacturing and that they can contain heavy metals. See the documentary "Blue Vinyl" for more information. You can borrow it from me. Also, phthalates are often added to enhance flexibility. These are loosely bound and can be ingested when children chew or suck on toys made from PVC.

#4 Low density polyethylene (LDPE). Often used for see-through dry cleaning bags and produce bags.

#5: Polypropylene (PP). Often used in yogurt containers.

#6: Polystyrene, or styrofoam. Not recycled. Styrene molecules can get into your food if heated, if the food is acidic or fatty, or through cutting action with a knife or fork. You may also swallow some styrene when you leave those teeth marks on the cup.

#7: Anything that does not fit into categories 1-6, like polycarbonate. Not recycled. Some people mistakenly believe that polycarbonate is better to use than other plastics. This is not true. Although it appears to be more durable and is easy to reuse, it contains a chemical called bisphenol A.

Several scientists in the last couple of decades have had disturbing findings related to Bisphenol A. Bisphenol A (BPA) was originally invented as an estrogen replacement, but did not come into wide usage until the discovery was made in the 1950s that it made a good plasticizer. Plasticizers are added to plastics to improve their properties. Bisphenol A makes plastics clearer and more flexible. It is not well bound into the polymer; however, and it is soluble in water. This much is agreed upon by the scientific community.

The Centers for Disease Control published a study today on bisphenol A. You can read a synopsis here. They found the levels of BPA in Americans to be higher than the "safety threshold."

Another article tells the history of the research into the affects of Bisphenol A on mammals. Much of this story is also recounted in Theo Colburn's book Our Stolen Future.

At first, it wasn't clear exactly what the effects of this chemical were. To understand them requires a different understanding of toxicity than what we are used to. Traditional toxicity studies assume that it is the dosage of a chemical that leads to its effect. When it comes to a chemical like Bisphenol A, it is not the amount, but the timing of the exposure that is important. Because it is similar in shape to estrogen, the human body can mistake it for estrogen. One single molecule is enough to confuse the endocrine system. It is especially dangerous to developing fetuses and children. BPA exposure at a young age can lead to cancer, obesity, and fertility problems as an adult. (For this reason, I beg of everyone: do not feed babies with polycarbonate bottles- please use glass!) The effect on adults is less clear; however, some studies have found that exposure does lead to an increase in diabetes, obesity and cancer even in adults.

While independent and government scientists are getting results that would suggest that this chemical is dangerous, industry scientists are creating confusion by casting doubts on their results. Meanwhile, people around the world are consuming this product. As Ana Soto says in the article, “Now the industry will say that animals are not humans, which you can say as much as you wish, but that brings us to a situation; in order to know what is happening to humans, what are you going to do? Intoxicate pregnant women on purpose? In any case, we're already exposing people, because 95% of us have bisphenol A in our urine, so the experiment cannot even be done.”

Please avoid the use of plastics whenever possible. Every piece of plastic ever manufactured is still on the earth with us, and a lot of it is in the ocean. Plastic photodegrades into particle-size plastic shards that get mistaken for food by fish and mammals. Bioplastic is a good idea, but it does not degrade well in the ocean. A better solution is for federal, state and local governments to require take-back programs and require manufacturers to reuse or recycle what they make.