Food Packaging And Storage: What Are The Different Types of Plastics? What Do Plastic Recycle Codes Tell you? Guide to Understanding Plastics
Upon hearing that BPA-free does not automatically mean safer, it lead me to research plastic a little further.
What types of products are made out of Polycarbonate Plastic? Re-usable water-bottles, water cooler jugs, and CDs and DVDs are the ones we are most familiar with. Until recently, baby bottles and sippy cups contained BPA.
- In 2011, the United States generated almost 14 million tons of plastics as containers and packaging, aboutt 11 million tons as durable goods, such as appliances, and almost 7 million tons as nondurable goods, for example plates and cups.
- Only 8 percent of the total plastic waste generated in 2011 was recovered for recycling
After reading this article, it really made me think about the products I use.
The research by doctors from California Pacific Medical Center in San Francisco is part of a growing body of evidence looking at the negative health effects of BPA, a plastic hardening chemical found in food containers, cans and even sales receipts, as well as methylparaben, a lesser-known preservative found in cosmetics and personal care products.
In the latest study, researchers took noncancerous breast cells from high-risk patients, grew them in a laboratory and found that once the cells were exposed to bisphenol A and methylparaben, they started behaving like cancer cells.
Tamoxifen, a drug designed to prevent or treat cancer, slows down the growth of both healthy and cancerous breast cells and ultimately leads to their death. But when tamoxifen was introduced in the lab, the cells exposed to the two chemicals kept growing and didn’t die, said Dr. William Goodson, senior clinical research scientist at California Pacific Medical Center Research Institute and lead author of the study.
According to this University of Texas study, published in Environmental Health Perspectives, it confirmed that almost ALL plastics leach hormone-disrupting chemicals, even those who are labeled BPA-free.
Inside the arrow recycle symbol, is a number. Polycarbonate (PC) recycling code is usually #3 or #7. You may find that a BPA- free product also has the #7; thus it is may be polycarbonate or Polyethersulfone (PES) or a mix of different types of resins , but does not contain BPA. But, I have to wonder, does that mean it contains BPS or other hormone-disrupting chemicals? Because there are no labeling required, we don’t know what is used to replace the BPA component and what additives are used to make the end product?
Plastic is all around us. Realistically, it is hard to avoid or completely eliminate all plastic… and in some situations, not always practical to use glass, but whenever possible, it just seems like the prudent thing to do would be to limit your use of plastic items.
Avoid plastic whenever possible, but let’s review the different types and the most prevalent ones found in most of our everyday items.
Plastic Recycling Symbol #1: PET or PETE, polyethylene terephthalate
Typically all one-time use, disposable water bottles are made of PET. I also found that Soda, salad dressings, spice bottles, and peanut butter containers have the #1.
Look for yourself. Next time you are at the grocery store, or check the products you have at your house now–flip the bottle over and look at the recycle code number. Do you see the #1?
- PET bottles don’t contain bisphenol A, according to the National Association for PET Container Resources (NAPCOR), a trade association for the PET plastic industry. Scientific research on the potential for PET bottles to leach harmful substance is sparse.
- Report low leaching levels but
- Not everyone buys that line, however. William Shotyk, a geochemistry professor at the University of Heidelberg, has published two studies (here and here) that show that antimony, a potentially toxic trace element, leaches from PET bottles over time. This doesn’t mean there is a clear health risk, Shotyk says. But, he adds, “I would say it’s something to think about.”
- Antimony oxides (primarily antimony trioxide) are used as fire retardants for plastics, textiles, rubber, adhesives, pigments, and paper. (1)
PET is widely used and it is inexpensive, lightweight and easy to recycle.
Have you ever left bottled water in your car, and then later you took a sip and it taste plastic-y?
Plastic Recycling Symbol #2: High-Density Polyethylene Plastics (HDPE)
Mostly found in non-reusable items, such as
- Milk jugs
- juice containers
- some yogurt containers
- household containers- laundry and dishwasher detergent, bleach bottles, shampoo and
- some water bottles are made from HDPE.
It is reported to have low leaching levels, but not sure how much it has been tested.
I did found this chart that shows the Overview of Chemical Resistance of Resins to Chemical Categories at 20°
|E||30 Days of constant exposure causes no damage. Plastic may tolerate for years.|
|G||Little or no damage after 30 days of constant exposure to the reagent.|
|F||Some effect after 7 days of constant exposure to the reagent. The effect may be crazing, cracking, loss of strength or discoloration.|
|N||Not recommended. Immediate damage may occur. Depending on the plastic, the effect may be severe crazing, cracking, loss of strength, discoloration deformation, dissolution or permeation loss.|
It looks like it depends on what the substance (liquid) is and what type of plastic it is put into, and also the conditions to which the product is subjected to (heat or cold and cracks) that all bods to the safety of an item.
Plastic Recycling Symbol #3: Vinyl (V) or Polyvinyl Chloride (PVC)
PVC. Many think pipes. Yes, most pipes are made from PVC, as well as some food packaging, cleaning products, shampoos, shower curtains, vinyl flooring and medical equipment.
Polyvinyl chloride, commonly abbreviated PVC, is the third-most widely produced plastic, after polyethylene and polypropylene. PVC is used in construction because it is more effective than traditional materials such as copper, iron or wood in pipe and profile applications. It can be made softer and more flexible by the addition of plasticizers, the most widely used being phthalates. In this form, it is also used in clothing and upholstery, electrical cable insulation, inflatable products and many applications in which it replaces rubber.
The issue with PVC is many report that it is toxic through its entire process. Because of its majority chlorine content, when PVC burns in fires two extremely hazardous substances, hydrogen chloride gas and dioxin are formed which present both acute and chronic health hazards to building occupants, fire fighters and surrounding communities. In addition, when PVC burns, some 100 different toxic compounds are produced.
According to the EPA, Dioxins” refers to a group of toxic chemical compounds that share certain chemical structures and biological characteristics. Dioxins can be released into the environment through forest fires, backyard burning of trash, certain industrial activities, and residue from past commercial burning of waste. Dioxins break down very slowly and past releases of dioxins from both man-made and natural sources still exist in the environment. Almost every living creature has been exposed to dioxins. Studies have shown that exposure to dioxins at high enough levels may cause a number of adverse health effects, including cancer. The health effects associated with dioxins depend on a variety of factors including: the level of exposure, when someone was exposed, and for how long and how often someone is exposed.
Acute (short-term) exposure to high levels of vinyl chloride in air has resulted in central nervous system effects (CNS), such as dizziness, drowsiness, and headaches in humans. Chronic (long-term) exposure to vinyl chloride through inhalation and oral exposure in humans has resulted in liver damage. Cancer is a major concern from exposure to vinyl chloride via inhalation, as vinyl chloride exposure has been shown to increase the risk of a rare form of liver cancer in humans. EPA has classified vinyl chloride as a Group A, human carcinogen.
If you have children, be sure to look at toys, lunch boxes and packbacks, as they may be made from PVC.
What are phthalates?
Phthalates are a group of endocrine-disrupting chemicals commonly used to render plastics soft and flexible. They are found in a wide variety of common products including plastics, cosmetics, pharmaceuticals, baby care products, building materials, modeling clay, automobiles, cleaning materials and insecticides. Phthalates are readily absorbed through the skin (Janjua, 2008) and can also enter the body through inhalation or medical injection procedures (Schettler, 2005).
Plastic Recycling Symbol #4: Low density polyethylene (LDPE)
Found in: shopping bags, dry-cleaning bags, frozen food bags, and some (squeezable) bottles and containers.
Curbside recycling for these types of bags are not available but some stores will take back plastic bags for recycling.
The quandary for paper or plastic exists for an Eco-minded person, but from all I have read, paper is “better” than plastic. Plastic bags need sunlight to degrade, as they are not bio-degradable.
What is the difference between the terms degradable and bio-degradable?
There are two primary differences between ‘degradable’ and ‘biodegradable’. Firstly, heat, moisture and/or UV exposure most often causes the degradation of a degradable product, whereas microorganisms degrade a biodegradable product. Secondly, degradable products tend to take much longer to break down into carbon dioxide, biomass and water.
Eventually degradable products would break down small enough to become bio-degradable… could take up to 500 years to be complete the process though.
So, recently I have been re-using my paper grocery bags. Once home, I unpack the items and then fold them up and put the empty bag(s) in my trunk. Therefore the next time I go shopping, I will have them. I need to start using the recyclable bags.
Plastic Recycling Symbol #5: Polypropylene (PP)
Found in: Tupperware and other storage containers, some yogurt and cheese containers. Most bottle tops are made from PP. Also, some baby bottles are now made from PP, rather than Polycarbonate (BPA)
I was glad to learn that Tupperware doesn’t contain BPA, as it appears that Polypropylene does NOT contain BPA.
It is reported to have low leaching. And appears to be better than #1, #3, #6 and #7. But, again, still plastic. And many times it isn’t the plastic itself that is harmful, but the additives that are used to make the end product.
Although it does say, Microwave and Dishwasher safe, if you are going to store your food in plastic (rather than glass) it probably makes good sense to just hand wash with warm water and mild soap (preferable a non-phosphate soap). As we have learned, plastic breaks down. Cracks and scratches, eventually could lead to plastic leaching into our foods.
Plastic Recycling Symbol #6: Polystyrene (PS)
Polystyrene can be soft (as in Styrofoam) or hard (as in plastic plates and silverware).
- Polystyrene is made from petroleum, a non-sustainable, non-renewable, heavily polluting and fast-disappearing commodity.
- Polystyrene is not biodegradable. It takes several decades to hundreds of years for polystyrene to deteriorate in the environment or in a landfill.
Polystyrene food containers leach the toxin Styrene when they come into contact with warm food or drink, alcohol, oils and acidic foods causing human contamination
Wait. So, the coffee that is served in Styrofoam cups, actually breaks down when heated? Houston, we have a problem.
Plastic Recycling Symbol #7: Other. Miscellaneous
Polycarbonate typically has BPA. If a product is labeled BPA- free, do they just replace it with BPS or another hormone-disrupting chemicals?! It is next to impossible to know what the miscellaneous #7 contains because labeling isn’t required.
I just checked my Nalgene bottle. BPA-free on the label, but #7 on the bottom. Their website says they, like the Eastman bottles, use copolyester, which is a plastic like substance similar to Polycarbonate but does not contain BPA. Is it safe? I don’t know. The company claims it is… but Eastman also used to claim BPA was safe.
With plastic and many other substances, we can only go on what we know at the time. That is why it is important to stay current with the most recent updates.
Researchers from the University of Texas at Austin, the Lombardi Comprehensive Cancer Center at Georgetown University, and the CertiChem and PlastiPure companies of Austin, Texas, recently published a study online in the March 2, 2011, issue of the journal Environmental Health Perspectives that addresses this need.
But BPA is only part of the story. For their study, the research team tested more than 500 BPA-free consumer products for other estrogenically active chemicals and found that 92 percent of the products readily leached the potentially hazardous compounds. Leaching was more common when products experienced ordinary stresses like dishwashing, microwaving and exposure to sunlight.
The most unsettling? The highest levels were detected from baby and water bottles using Polyethersulfone (PES) or polyethylene terephthalate glycol (PETG) with measurements at and above the level of the BPA-containing polycarbonate products those plastics replaced.
I thought this was a decent point:
Then there are the new plastics on the market for BPA-free bottles, can liners, and other such products. The Environmental Protection Agency (EPA) also has an effort underway through its Design for Environment program to examine the alternatives to the BPA-based thermal papers used in receipts, currency, and other similarly printed papers. But because the U.S. system of regulating chemicals relies primarily on information supplied by a material’s manufacturer, we know relatively little about these new plastics.
I know this post got to be rather long, seeing we went through the top 7 most used plastics. Hopefully you learned how to better understand the different types of plastics and how to read the recycle code, and let it help you decide which products to buy.
And even if you are skeptical about some of the studies and their conclusions that other plastic alternatives are not safe, perhaps the take away point is, plastic may have it purposes, but overuse and too much exposure could lead to potential health issues. The point I keep thinking about is, they told us BPA was safe, and considering the FDA has actually banned it (on some items) and a few other countries have declared BPA a toxic substance, I am now cautious of plastic and the newer plastic alternatives.
When you use plastic:
- avoid #3, #6 and be cautious of #7 because they are mixed resins that are not labeled, and they are not recyclable and may leach hormone-disrupting chemicals.
- do not heat, dishwasher or microwave plastic tupperware, even if it says it is “safe”. Plastic can break down and when that happens, the chemicals can leach into our food.
Do you still look at plastic the same?
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