by Catherine Haug, April 12, 2013
(photo, right, from Wikipedia)
If you are a recycler, you know that there are not many plastics that we can recycle here in the Flathead. In fact, about the only plastic we can recycle here are the white or semi-transparent milk jugs (code #2).
But did you know that paying attention to the recycle codes on plastic containers could help reduce your exposure to estrogenic and other toxins in the plastic?
You’ve probably heard me say that ALL plastics are toxic (not just BPA/BPS). One study (4) proves that at least 95% of all plastic products tested were positive for estrogenic activity. I maintain the other 5% are also suspect for some type of toxicity, if not yet proven.
The codes to avoid are #3, #6 or #7 (these have red headings in the descriptions below). Those that are generally considered ‘safe’ (but still have potential toxicity, or may be toxic in ways that have not yet been discovered) are #1, #2, #4, and #5. See below for more about each code, and how to find them on a product or container. (image, left and below, from TheDailyGreen.com (11)
In this article I discuss:
- The seven plastic recycle codes and potential toxic risk for each;
- “Green” and biodegradable plastics;
- Tips to reduce plastic use.
Plastic recycle codes
How to find the codes:
The code is a triangle of three arrows, with a number inside the triangle (see image, left, from TheDailyGreen.com (11)). It may also include the resin abbreviation below the triangle; e.g., V for #3.
The code is typically found on the bottom of containers; it can be more difficult to find on other objects like toys, and it may also be quite small so that you need a magnifying glass to find it.
On clothing, it is usually printed on the tag that has cleaning instructions, but may instead be on the removable tag.
Plastic #1: Polyethylene Terephthalate (PET or PETE)
Generally considered safe, but the toxic heavy metal antimony is used during the manufacture of PET, which can then leak from the plastic into the food/beverage in the container. And the longer the container sits on a shelf (in a warehouse, store or your pantry/refrigerator), the greater the dose of antimony. Exposure of the container to to sunlight, higher temperatures, and varying pH levels affects the level of toxicity. (2)
Another potential toxin comes from brominated compounds. Bromine is especially toxic to the nervous system, and can trigger psychological and psychotic symptoms. (3)
The chemical name Terephthalate implies that phthalates are used in the plastic, and could leach into liquids stored in these containers. See Code #3, bellow, for more about phthalates.
PET is most commonly used for (8, 11):
- bottles for soft drinks, sport drinks, water, juice, mouthwash;
- containers for condiments (ketchup, salad dressing, peanut butter, jams and jellies);
- containers for supplements;
- polar fleece and other fibers;
- tote bags, straps;
- furniture, carpet;
- paneling.
Plastic #2: High Density Polyethylene (HDPE)
This plastic has been found to release estrogenic chemicals. See NOTE about “hormone disruptor” and “estrogenic toxicity” below.
HDPE is most commonly used for (8,11):
- milk, water and juice bottles;
- “jars” for powdered food supplements; e.g., protein powders, lecithin
- bottles for laundry detergents, cleaning supplies and shampoo;
- grocery bags and cereal box liners;
- containers for supplements;
- floor tile, drainage pipe, lumber:
- benches, picnic tables;
- doghouses, fencing.Read more: http://www.thedailygreen.com/green-homes/latest/recycling-symbols-plastics-460321#ixzz2QTV0yiXz
Plastic #3: Polyvinyl Chloride (PVC)
We are all familiar with PVC, as it is used for water pipes in modern building construction. But is one of the more toxic types of plastic and I don’t want to drink water that has passed through a PVC pipe. It also shows up in other things that you might not suspect – like artificial Christmas Trees. PVC degrades over time, giving off toxins in the process. For this reason, I’ve gotten rid of all my artificial Christmas garlands and trees, as my cats love to chew on the fake needles which are PVC.
The most common toxins in PVC fall under the family name of phthalates. These are used to soften the plastic, but they also are used in some cosmetics and shampoo products. Phthalates are known to be “gender bending.” They also disrupt the endocrine systems of wildlife, “causing testicular cancer, genital deformations, low sperm counts and infertility in a number of species, including polar bears, deer, whales and otters, just to name a few.”(8) They can also cause these same problems in humans, especially infants and children whose bodies are still developing. See NOTE about “hormone disruptor” and “estrogenic toxicity” below.
Phthalates used in soft flooring have been linked to chronic diseases including allergies, asthma and autism.
PVC is most commonly used for (8,11):
- bags for bedding;
- shrink wrap;
- deli and meat wrap;
- Saran © and other plastic wrap;
- cooking oil bottles << this one is especially a health risk because many of its toxic contaminants readily leach into and dissolve in the oil
- plastic toys;
- medical equipment;
- blister-packs for medication;
- wire jacketing;
- siding, windows, piping;
- artificial holiday garlands and Christmas trees;
- soft, flexible plastic flooring, such as vinyl or those padded play-mat floors for kids (often used in day cares and kindergartens, too).
I encourage my butcher to wrap my meat and fish in butcher paper rather than meat wrap. On the rare occasion when I buy meat in meat wrap, I re-wrap it as soon as I get home, and I NEVER put clear meat-wrap in the freezer, as freezing causes it to break down faster, releasing the toxins into the food.
Plastic #4: Low Density Polyethylene (LDPE)
This is also considered a low-hazard plastic, and does not contain BPA. However, like HDPE, it may post risk of leaching estrogenic chemicals. See NOTE about “hormone disruptor” and “estrogenic toxicity” below.
LDPE is commonly used for (8,11):
- bags for bread;
- bags for newspapers;
- bags for fresh produce;
- household garbage bags;
- squeezable bottles;
- frozen food bags;
- coating of paper milk cartons and hot/cold beverage cups;
- clothing, carpet, furniture.
Plastic #5: Polypropylene (PP)
Another plastic considered food-grade, PP has a high-heat tolerance, which means it is unlikely to leach bad chemicals, but more testing is needed to study this. One study published Science, Nov 7, 2008 by McDonald, et. al., of the Department of Pharmacology, University of Alberta, Edmonton, Alberta: “Bioactive contaminants leach from disposable laboratory plasticware” (5), found that many of the toxic chemicals required for the manufacture of polypropylene will leach into water, including dimethyl sulfoxide (DMSO), and methanol (wood alcohol).
PP is used to make food grade containers for (8,11):
- yogurt, cottage cheese, tub margarines, and deli foods;
- ketchup bottles;
- caps, straws;
- take-up meals;
- medication containers;
- laboratory plasticware, such as test tubes, pipette tips, and multiwell assay or culture plates
Plastic #6: Polystyrene (PS)
Another name for polystyrene is Styrofoam, and is very common in our take-out culture. But some cities in the US have banned it within city limits. A movement among some Pacific Coastal cities in the early 1990s to ban its use caused MacDonalds and other fast-food chains to find another type of takeout container. However, it is still prevalent in many restaurants and is available in the picnic section of many grocers throughout Montana.
PS is made from styrene (vinyl benzene), which is a highly toxic substance that damages the nervous system and has been linked to cancer. While low levels of styrene are present naturally in many plants, including edible fruits and vegetables, the styrene used to make plastic is made from benzene, which is usually made from petroleum.
Polystyrene is known to leach styrene into water and foods, especially when it is heated (as by hot coffee or soup in a styrofoam cup).
Styrene is considered a “hazardous chemical” that is easily absorbed through the skin, lungs or eyes to enter the blood stream and circulate around the body. It’s metabolic products such as styrene oxide are also known to be toxic. The EPA describes styrene as a “suspected toxin to the gastrointestinal tract, kidney, and respiratory system, among others. … Chronic exposure to styrene leads to tiredness/lethargy, memory deficits, headaches and vertigo.” (9).
Polystyrene is widely used by the commercial and fast food industries as (8,11):
- cups, plates, bowls;
- take-out containers;
- egg cartons;
- meat trays;
- aspirin bottles.
It is also used as foam packaging for electronics and other devises for the home and business, and is used by many young children for art projects, a practice that I think should be discouraged.
Plastic #7: Other
Plastics that don’t fit into the previous categories, or are made from more than one of the above categories, are coded #7. Wikipedia (1) indicates that polycarbonate and ABS (Acrylonitrile butadiene styrene) fall into this category. Lego bricks are an example of ABS.
Because it is difficult to know what is used to make the different plastics in this category, it is considered one to avoid. #7 plastics likely contain bisphenols (BPB, BPF, BPS, BPAF, and so on), which have been shown to be endocrine disrupters and have estrogenic activity. This is of special concern for infants and children whose bodies are still developing and so are at greater risk of harm. See NOTE about “hormone disruptor” and “estrogenic toxicity” below.
Exposure in the uterus to bisphenols can result in chromosomal errors in a developing fetus, causing “spontaneous miscarriages and genetic damage.” (8)
Bisphenols have also been implicated in “leading to decreased sperm quality, early puberty, stimulation of mammary gland development, disrupted reproductive cycles and ovarian dysfunction, cancer and heart disease.” (8)
BPA exposure has been linked with general and central obesity in our adult population, and with insulin resistance, considered a precursor to type-2 diabetes and possibly also Alzheimer’s. (6,7)
Examples of this code (8,11):
- three- and five-gallon water bottles;
- certain food containers;
- toys (e.g., legos);
- ‘bullet-proof’ materials, sunglasses, DVDs, iPod and computer case;
- signs and displays;
- nylon. (12)
NOTE about “hormone disruptor” and “estrogenic toxicity:”
These terms are used in the code descriptions that follow, and mean the substance can potentially disrupt your hormones, or alter the structure/function of your cells, and thus pose risks especially to developing fetuses, infants and children. This type of toxicity can also cause cancers.
Estrogenic toxicity is specific to the hormone ‘estrogen,’ and means that the substance mimics estrogen or binds to estrogen binding sites. Many types of cancers are estrogenic, the most common being a type of breast cancer. Note that animals are also affected by estrogenic toxicity; for example, fish in the ocean where waste-plastics congregate.
Estrogenic toxicity may also be ‘gender bending’ – causing males to become more female (both in physical makeup and behavior).
“Green” and Biodegradable Plastics
I am not convinced that biodegradable plastics are the solution to plastic pollution. Many are not so readily biodegradable in landfills, but do degrade better in an active compost pile.
Neither am I convinced that plastics made from food oils (soy, corn, canola, etc) are any safer than those made from petroleum. Many of the same chemicals required for manufacturing the plastic resins from petroleum are also required to make the resins from vegetable oils. And many of those chemicals are toxic.
One of the harms of petroleum-derived plastics is the release of Volatile Organic Compounds (VOCs), and these may also be released by vegetable-derived plastics.
Some recycled plastics are turned into new plastics; perhaps the most common is the polyethylene plastic in water and pop bottles (#1 and #4 plastics), which is turned into fibers used for insulating clothing, carpets and more. While this does reduce the production of new plastics, it doesn’t diminish our addiction to plastics; nor does it erase the toxicity of the original plastic.
Tips to reduce plastic use
The following is from Mercola (8), with Cat’s notes in square brackets []:
- Use reusable shopping bags for groceries [and avoid using plastic bags for produce; bring your own paper bags or make cloth bags for this purpose. You can also save a plastic bag to bring with you, but these do degrade with use so I advise reusing only once.]
- Bring your own mug for coffee.
- Bring drinking water from home in glass water bottles, instead of buying bottled water. [Especially important in cars, as plastic water bottles exposed to heat in a closed-up car leach more toxins than those kept in a cold place. Glass is not known to leach any toxins.]
- Store foods in the freezer in glass mason jars [or meats in butcher paper] as opposed to plastic bags and plastic wrap.
- Take your own non-plastic container to restaurants for leftovers.
- Request no plastic wrap on your newspaper or dry cleaning.
- Avoid disposable utensils [and this goes for plastic stir sticks for hot beverages, as well].
- Buy foods in bulk when you can [then store in glass mason jars as 1st choice; reused #2 plastic ‘jars’ from powdered supplements like protein powder as 2nd choice.].
- Replace plastic [and melamine] kitchenware with glass or ceramic alternatives.
- Use stainless steel or high-heat-resistant nylon for utensils in-lieu-of plastics. [Many of these utensils are now available made from silicon. I’m wary of these; not much study has yet been done on toxicity of silicone plastics. See my note about silicone plastics, below].
A note about silicone plastics
Silicon is an element directly below carbon on the periodic table, and behaves much like carbon in chemical reactions. Chemical resins similar to those made from carbon, oxygen and hydrogen can be made from silicon, oxygen and hydrogen, and these include the plastic resins. Because carbon and silicon are so similar, I suspect that there would be similar toxicity from their plastic versions.
Silicon is found in sand and is a major component of crystal, glass and ceramics, which are time-tested substances that have been used by humans for centuries. But silicone resins are fairly new in human history.
References
- Green Plastics: An Introduction to the New Science of Biodegradable Plastics
- Water Research, Volume 42, Issue 3, February 2008, Pages 551–556
- Environment International Volume 38, Issue 1, January 2012, Pages 45–53
- Environmental Health Perspectives March 2, 2011 (Epub Ahead of Print)
- Science. 2008 Nov 7;322(5903):917.
- Environmental Research 2011 Aug;111(6):825-30.
- The Journal of Clinical Endocrinology and Metabolism. 2012 Feb;97(2):E223-7.
- Mercola: How to Recognize the Plastics That are Hazardous to You
- Wikipedia: Styrene;
- Wikipedia: Plastic Recycling
- TheDailyGreen.com: What Do Recycling Symbols on Plastics Mean?