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September 25, 2005


Mitra Ardron

I think you've hit the mark here - PLA is more expensive, so it only really appeals to companies with a social conscience. But most of my clients don't want to switch to PLA if it means supporting GMO agriculture (I agree with you that there is no GMO in the plastic, but its certainly encouraging GMO growing to have a ready market for more corn).

If NatureWorks is serious about tackling the socially responsible market then it seems to me that they need to offer a GMO free product before PLA gets such a bad name that its hard for them to counter it later.

- Mitra Ardron

Rob Nathan

I know I am commenting on a blog posting from a long time ago, but your feedback (and your readers') would be appreciated.

I am an industrial designer and I have been working on PLA packaging at the company for which I work, Edge Ideas. Our main brand is SOLE Custom Footbeds (http://www.yoursole.com).

We have changed our PET packaging to PLA packaging. Originally we had made the packaging out of paperboard but it was not durable enough. We are actually one of a very small group of manufacturers to produce PLA packaging for a non-food-related product.

But we are now rethinking the change. The big question is, "What is the most environmentally sustainable packaging material?" PET, PLA, or would paper or a different biopolymer be even better? Perhaps Metabolix's Mirel biopolymer? The EU is working on Sustainpack to figure out a total packaging solution, but results of this are years away. What about right now?

• We have had to add 5% or so strength modifiers to the PLA so that it is durable enough for our application. Adding the strength modifiers means that the package is no longer certifiably compostable. Since it is not compostable, it will all end up in landfills, where the vast majority of PET ends up as well, regardless of recycling efforts. There are no PLA recycling projects yet.
• PLA still uses less energy than a comparable PET package.
• PLA produces less carbon dioxide and uses slightly less water than PET.
• PLA uses less petroleum since there is none used in the actual packaging, though it still uses petroleum-based fertilizer to grow the corn, to drive the tractors, etc.
• By using PLA some think that we are supporting GM corn, which comes with its own set of environmental and health concerns. NatureWorks has an offset program that I just found out about and that we will hopefully begin to use. They track every ounce of resin that a company uses, translate it into bushels of corn that would be needed and will then buy that amount of conventionally grown corn. Therefore, our PLA may not have been made entirely from non-GM corn, but the amount of corn we are using is at least going into the stream of PLA and someone will be using it. This is the same as green power offset programs using wind power and the like. If Natureworks’ customers in North America asked for PLA from non-GM corn, like their European customers already do, then NatureWorks would only buy non-GM corn.

Is there a "best" material, or is this a question of doing what may be the best for now, as we wait for a full packaging system to be developed, that is more sustainable from cradle to grave?

What do you think of the question? Any input would be greatly appreciated.

Thank you,
Rob Nathan

Carl Zamecnik

My company makes food packaging from PET and Polypro. We had looked at PLA for several projects, but were hesitant to put out a product that softened at 114F, and needed to be shipped to customers in refrigerated trucks, and stored in climate controlled conditions. Pretty expensive. However no one counts the added energy required for that kind of handling. In addition, there's the biodegrading aspect we looked at, and were pretty shocked. The plastic doesn't biodegrade in landfills, in seawater, or in compost situations at home. If you read their claims carefully, they only degrade in "commercially managed" compost facilities that generate sustained heat of 140F, of which there are about 100 in the country, and only 25% of those take municipal waste. That means only a tiny fraction of that material will ever biodegrade the way they claim. In fact it has the same 100-1000 year life as regular plastic when landfilled. So where's the green?
We have been involved in a different approach that we are bringing to market, and that is Bio-PET. It is actually APET material with a proprietary addative that allows the plastic to biodegrade in landfills, composting (even backyard style), in seawater, in sewage sludge, and of course the "commercially managed" compost facilities. While this is conventionally made PET material produced from petroleum, we feel that it's afterlife is the real impact on the planet. We like the fact that this Bio-PET will completely degrade in 6 months to 5 years depending on bioactivity of it's environment. That sure is better than 100 to 1000 years. Plus, in landfills, it anaerobically degrades to produce methane. This methane is now an important resource at landfills, and is siphoned off and sold to heat homes, and even make ethanol.
And the impact on petroleum? Walmart is changing 114 million packages to PLA material, saving they say an estimated 800,000 gallons of gas. The U.S. used 138 BILLION gallons of gas in 2006. Saving 800,000 gallons amounts to about 5 ten thousandths of ONE percent savings. That's the biggest retailer in the world making a huge volume commitment to PLA usage, and the savings in petroleum is way too small to even see. I think the waste problem is the most pressing one here, and our Bio-PET seems to be a good answer for now. Check us out at www.candlamerica.com.

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