Tuesday, January 25, 2011

Reuse that PET bottle, please!

I try and minimize the time I spend at websites that cater to a "all plastic is evil" philosophy, (or anything close to it), but this one made me laugh (thank goodness, as doing so prevented me from crying). Like many blogs out there, the post was more or less a cut-and-paste of something from somewhere else that keeps getting posting around the web ad infinitum. [*] The title appears to be quite real however, because it is so meaningless: "Plastics Part 2: The world’s most popular PET" ???? To have a "most popular" item implies that one is choosing from a list of options, but unfortunately PET is not a list of options, it is only PET. Maybe the author thought that PET is an abbreviation for "polyester" and are unaware that is stands for "polyethylene terephthalate".

The post continues along nicely with generic information about PET and its uses. The last two paragraphs however, have some uninformed ideas that are repeated way too much. Like this one:
"One common way that plastic leaches (phthalates) is through heat and sun exposure–for example, leaving a bottle of water in the car, using a container or bottle multiple times (like when refilling a disposable water bottle, and/or using a bottle that has contained a food or beverage product for months or years, like a shelved bottle of mayonnaise or honey)."
Fine, diffusion (i.e., migration) of pretty much anything increases with heat, but if this is a concern, then reusing a bottle it the ideal way to go. The bottle has only a limited amount of whatever nasty in it, and the initial fill will remove some of it, maybe a lot of it if the product spent a long time between manufacture and consumption. When the bottle is refilled, there is potentially less material available for diffusion, and decrease in potential means that less will diffuse into the fill each time. Reuse the bottle enough and you will see exceedingly low levels of whatever the concern is. Considering that an objective of reducing plastic usage is to reuse when possible, I don't see why this so many people are against resue of a plastic bottle.

And then the last paragraph leads off with a misleading statement
"There has also been concern with the compound Bisphenol-A, which is regularly used in plastic products."
Since the rest of the post has been about PET, this makes it appear that BPA is a concern in PET, certainly not the case.

So much misinformation, so little time.

[*] In many cases, these seem to be autogenerated, probably with the idea of making money off the ads. The blog discussed here does not fit into this classification, as there real contributors listed on it.


Frank Van Haste said...

G'day, John!

Here's a thought; how about water in pre-leached bottles? Fill PET bottles and let them sit in the sun for six months so all the phthalates and BPA will leach out. Then empty them (with the H2O going to non-potable uses) and refill the now reduced-evil bottles with fresh water. Re-cap and sell at a premium. You could label 'em as phthalate & BPA-free!

Think there may be a business there?



John said...

You could give it a shot, but I'll pass. And since you just disclosed the idea, you've got a year from today to file the patent. (Or did you already see the potential months ago and already have an application on file?)

Anonymous said...

You chose to misrepresent the post on the "World's Most Popular PET" because of your bias towards plastic. The post reads "Polyethylene Therephthalate (PET or PETE) is a plastic resin in the polyester family. PET is most often produced for synthetic fibers, and containers for beverages, food and other liquids. Though it is not the most produced plastic internationally, it is one of the most identifiable and familiar plastics to us and one of the most widely-distributed around the world."
The title clearly has context and humor, which you missed entirely, and the author did not say PET was made from polyester.

John said...

Dear Anonymous,

(Sadly you are anonymous; ever notice how most people around aren't anonymous?)

Let me address the 3 issues that you raised.

1) "[I] chose to misrepresent the post...". No, everything is a direct quote from the article, and I included a link to give everyone a chance to confirm this.

2) "...[my] bias towards plastic". I certainly hope not. Yes, my education heavily emphasized polymers, and most of my career experience is in that area, but as a result, I am well aware of the limitations of plastics. If I were to propose and work towards making something from plastic when a ceramic or metal would be a better choice, that would be irresponsible of me. But at the same time, the opposite is true too - plastics should be used in many cases.

3) "The title clearly has context and humor..." I guess I'm still missing the humor. A double entendre on the word PET? Maybe, but why was it being made? The phase "The world's most popular pet" doesn't ring a bell to me. And being apparently humor impaired, this then means that I didn't "choose" to misrepresent the post either, does it?

Lastly, you didn't respond to two other criticisms that I had of the post - that reusing a plastic bottle will actually decrease your exposure to whatever undesirable (real or imaginary) chemicals can leach out of the bottle, and that BPA is not an issue with PET bottles. As I said in the original post, these ideas that I attacked are being repeated around the blogosphere way to much as they are not true.

Please feel free to respond again, anonymously even, but ad hominem attacks, even subtle one such as occurred here, are not welcomed.