Sunday, May 4, 2008

Water Bottles - Part 2 of 2


I remember something from back when I got my small, medium, and large water bottles, but there were a few things that I didn't bother to learn and others that I've forgotten. Besides, that was several years ago and information has a way of becoming outdated as new developments are made and new information is disseminated.

Plastic items that can be recycled if proper facilities exist have an international recycling resin identification code inside the recycle symbol of three arrows chasing each other around in the form of a triangle. This symbol may be found on the bottom of plastic bottles and other items.

Following are the symbols for the various categories for plastic and a discussion pertinent to each code:

Also labeled as PET, is polyethylene terephthalate. These containers are almost the best for flavor and odor. Common uses are beverage bottles from .5 liter water bottles to 2 liter soda bottles, shampoo bottles, jars for food such as peanut butter, plastic film, and microwavable packaging. PET bottles have the most common resin used in disposable bottles, are the most recyclable, are able to substitute for coal in power plants, and the recycled products are able to be used to make clothing such as Polar fleece. The myths about them are flying indiscriminately.

One baseless rumor is that PET bottles should be used only once because they can leach chemicals such as DEHA, a known carcinogen, and benzyl butyl phthalate (BBP), a potential hormone disrupter. The problem with this is that DEHA is not in PET bottles, at all, yet even respected publications such as National Geographic's Green Guide are helping spread the rumor. The other part of the myth, about BBP, isn't mentioned in any credible source that I've found. Because those that warn against it are the same that warn about DEHA, until I learn otherwise, I'm going to believe it's another myth, an instance of guilt by association especially since another Green Guide article says that PETE bottles do NOT leach toxins.

The other reason we shouldn't reuse PET bottles that I've read and heard about, and seen on various television programs is because bacteria builds up and they're hard to clean. Strangely enough, none of the advisors ever say the same thing about other bottles such as plastic canteens or other bottles that are similarly shaped. Along with other things I've learned, it's as though they want to keep us buying these bottles continuously for some reason (company profits?), wasting our money, and disregarding the horrendous amount of pollution that results.

A valid concern that isn't mentioned as often as the myths is about antimony. Antimony trioxide, a catalyst often used in the production of PET, remains after production and migrates out of a bottle into food and drinks. Even though its toxicity is low, the Swiss Federal Office of Public Health and, several years later in 2006, a team of geochemists at the University of Heidelberg headed by William Shotyk, investigated the amount of antimony migration. Both studies found that small amounts of antimony migrate from the PET bottles into water, but that the health risk is negligible compared to the tolerance level set by the World Health Organization.

What's important to us is that antimony continues to leach out over time. That means it's actually safer to reuse PET bottles than it is to consume the original liquid because they've been sitting for a while as antimony leaches out and accumulates. For this reason, we need to be sure to check the expiration date to ensure the original beverage hasn't been in the container too long and discard the liquid if it has. It's ironic that the conventional advice is to use a PET bottle only once, yet it's that first time that is most likely to contain the largest amounts of what we don't want to ingest.

Although safe, acetaldehyde may be unpleasant. Normally a colorless gas that forms in PET through the "abuse" of the material such as high temperatures and high pressures, acetaldehyde remains dissolved in the walls of the container and then diffuses into the product stored inside, altering the taste and aroma. It is safe, fruit juice has it naturally, but since water has no other flavors to conceal it, acetaldehyde in water simply tastes bad.

High Density Polyethylene containers are considered to be safe and non-leaching. They're freezable, translucent or opaque, and somewhat firm. They're used for things such as gallon jugs of water and milk and detergents.

Also labeled as PVC, polyvinyl chloride or vinyl should NOT be considered as safe for food or beverages because it has been linked to occupational cancers. Vinyl chloride is recognized by the WHO's International Agency for Research on Cancer (IARC) as a human carcinogen.

Use one of the safe plastics instead of #3. It is no longer used in children's toys in many places although some adult toys are still made of it. If you've heard or read about the dangers of plastics and dioxins and phthalates, this is it, Number 3, vinyl or PVC. It's commonly used for plumbing and building materials such as plastic pipes, electrical conduits, and gutters. It's been ubiquitous in children's toys and teethers, and is in everything from cosmetics to outdoor furniture, including shower curtains, shrink wrap, water bottles, foods such as salad dressing, and liquid detergent containers.

If you find it as a water bottle or other food or beverage container, don't buy it because traces of the deleterious chemicals can leach out into food. Stores such as Target won't sell anything with PVC, and the state of California is considering banning it from being used for packaging consumer products. The European Union has already banned the most widely used plasticizer used in PVC, DEHP (di-2-ethylhexyl phthalate).

[Edited on May 13 to add this Note: I deleted Wal-Mart as a store that won't sell anything with PVC because I went to Wal-Mart last night, 5/12/08, and saw that the camping department has several rain coats and rain ponchos for children and adults that are made of PVC.]

Low Density Polyethylene is considered to be safe and non-leaching. It is flexible, almost unbreakable, and may be either translucent or opaque. Some of the many uses are dry cleaning bags, produce bags, trash can liners, food storage containers, water bottles, and computer components.

Polypropylene is also considered to be safe and non-leaching. It is used for such common items as bottle caps, drinking straws, yogurt containers, cooking and eating utensils, and food, food storage and water containers. Also, appliances and car bumpers.

Polystyrene is not considered as one of the safe plastics because it can leach styrene, a possible human carcinogen according to the International Agency for Research on Cancer, into food. It is also suspected of disrupting hormones and affecting reproduction. The U.S. EPA monitors this toxin in America's drinking water. It is not easily recyclable and is blamed as being the second greatest pollutant behind aluminum. Several cities around the world, 20 in the U.S., have banned extruded PS. PS is commonly made into disposable cups, plastic tableware, meat trays, and carry-out food clamshell containers as well as packing peanuts and cases for cassettes and CDs. Extruded polystyrene is recognizable as Styrofoam and non-extruded PS, also known as expanded PS, is clear.

Since this covers everything not in #1 through #6, labels such as AS, PC, PLA, and SAN may be found instead of "Other." Be careful with this category because it contains both safe and unsafe plastics. I know of only four used for food or beverages of which three are considered to be safe:

1. AS (acrylonitrile styrene) is one of the plastics considered as safe. Despite its name, it has not been found to leach styrene. Being a plastic that's stronger, more rigid, resistant to temperature and chemicals, AS is commonly used in kitchenware such as dishes, bowls, utensils, and for dental products such as toothbrushes, as well as battery cases.

2. PC (polycarbonate), also sold as Lexan®. This is a great plastic because it is virtually unbreakable, is temperature-resistant, conveys and retains no flavors or odors and is available in a myriad of colors for many products ranging from baby bottles and sippy cups to water bottles to eyeglasses to riot shields to CDs to epoxy linings in tin food cans and some dental sealants. However, on April 14, the National Toxicology Program issued a Draft Brief on Bisphenol A (BPA) calling for comments by June 11, 2008.

On April 18, Nalgene bowed to its customers who have been concerned about reports of BPA leaching and is discontinuing its PC products in the next several months as is Playtex.

[Frankly, I suspect the NTP Draft Brief on BPA had more to do with Nalgene's decision because it had been defending its products containing BPA up to that point.]

Also on April 18, supposedly in response to Nalgene's announcement according to CNN, Health Canada announced that BPA is potentially harmful and may ban its use in baby bottles as well as take other measures.

As for retailers, outdoor co-ops, MEC in Canada and REI in the U.S., have pulled PC water bottles from their shelves and websites. Wal-Mart announced that it will discontinue selling BPA products for babies in Canada immediately. For the U.S., it will be in the following months. Both Wal-Mart and Toys "R" Us expect the baby products they sell to be BPA-free by the beginning of 2009.

The debate on BPA leaching from polycarbonate has raged for a number of years and the bottom line appears to be that if you want a PC container for food or beverages, you better hop to it and get what you want while it's still available.

Please note that when people or articles say, "Nalgene bottles," they're referring to the #7 PC bottles that leach BPA. But, Nalgene also makes containers out of the #2 HDPE, #4 LDPE, and #5 PP plastics that are considered to be safe, so there's no need to throw out the baby with the bath water.

3. PLA (polylactide acid) containers are safe plastics made from renewable resources such as corn and anything else with a high starch content like potatoes and sugar cane. They are everything that's good about plastic with only one negative: They melt when they get too hot. For example, you don't ever want to leave them in a car in warm weather or you'll return to a melted mess. In the same vein, you must follow instructions to hand-wash only because putting these in the dishwasher will cause a melt-down.

Although plant-based plastics can't be recycled, they may be composted in your backyard compost heap or in a city landfill. It takes about twelve days for PLA containers to decompose. Compare that to petroleum-based plastic which doesn't biodegrade and would take 100 years to photodegrade if it wasn't buried in landfills where it doesn't get the light and air needed to disintegrate.

4. SAN (styrene acrylonitrile) is the final plastic on this list that's considered to be safe. As with AS, the word "styrene" in the name does not mean that SAN products leach styrene. For example, Brita pitchers made of SAN have been tested by the National Sanitation Foundation (NSF) and there's been no evidence of leaching. As with AS, SAN is a higher quality plastic that's stronger, rigid, and resistant to chemical and high temperatures such as boiling water. Common uses are kitchenware, dishes, bowls, other food containers, toothbrushes, packaging material, computer products, and optical fibers.

To recap, the plastics that are bad for food and beverages are #3 V/PVC, #6 PS, and #7 PC.

#1 PET/PETE is bad because the original and subsequent beverages may sit long enough for antimony to leach out.

The plastics known as being safe are #2 HDPE, #4 LDPE, #5 PP, and #7 AS, PLA, and SAN.

I sincerely hope this helps. After reviewing everything and considering my needs, I ordered the 12 oz. ATB (#4 LDPE) bottle from Nalgene.

[On 5/22, I called about my order and was informed that PC products designed for children are no longer being sold, including the mini-ATBs that have PC only in the dust cap. I wrote to protest. In the meantime, I'm using a .5 liter stainless steel Thermos® that I bought six years ago for my hot tea.]


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