Plastics made out of Cargill Dow's corn-resin pellets break down in an industrial compost facility in about 45 days. (NEWSCOM)
EarthTalk: How green is corn-based plastic?
Pro: It’s compostable. Con: But only in an industrial composting facility.
By The Editors of E Magazine | July 11, 2008 edition
Q: What are the environmental pros and cons of corn-based plastic as an alternative to conventional petroleum-based plastic?
– Laura McInnes, Glasgow, Scotland
A: Polylactic acid (PLA), a plastic substitute made from fermented plant starch (usually corn), is quickly becoming a popular alternative to traditional petroleum-based plastics.
As more and more countries and states follow the lead of China, Ireland, South Africa, Uganda, and San Francisco in banning plastic grocery bags responsible for so much “white pollution” worldwide, PLA is poised to play a big role as a biodegradable replacement.
Proponents tout the use of PLA – which is technically “carbon neutral,” in that it comes from renewable, carbon-absorbing plants – as another way to reduce emissions of greenhouse gases in a warming world. PLA also does not emit toxic fumes when incinerated.
But critics say that PLA is far from a panacea for dealing with the world’s plastic waste problem. For one thing, although PLA does biodegrade, it does so very slowly. According to Elizabeth Royte, writing in Smithsonian magazine, PLA may well break down into its constituent parts (carbon dioxide and water) within three months in a “controlled composting environment,” that is, an industrial composting facility heated to 140 degrees F. and fed a steady diet of digestive microbes. But it will take far longer in a compost bin or a landfill packed so tightly that no light and little oxygen are available to assist in the process. Analysts estimate that a PLA bottle could take anywhere from 100 to 1,000 years to decompose in a landfill.
Another issue: Because PLA differs from regular plastic, it must be kept separate when recycled, lest it contaminate the recycling stream. Being plant-based, PLA must go to a composting facility, not a recycling facility. And that points up another problem: Only 113 industrial-grade composting facilities exist across the US today.
Another downside is that PLA is typically made from genetically modified corn, at least in the US. The world’s largest producer of PLA is NatureWorks, a subsidiary of Cargill, which is the world’s largest provider of genetically modified corn seed. With increasing demand for corn to make ethanol, let alone PLA, it’s no wonder Cargill and others are experimenting with plant genetics to produce higher yields. But the environmental and human-health impacts of genetic modification are still largely unknown.
PLA has promise as an alternative to conventional plastic once the means of disposal are worked out. For now, unless you’re certain that PLA bottle will end up in an industrial recycling plant, PLA may not be much better than plain old plastic. Meanwhile, consumers might do well by switching to reusable containers: using cloth bags, baskets, and backpacks for grocery shopping (most chains now sell reusable bags for less than a dollar apiece), and refillable bottles for beverages.
Got an environmental question? Write: EarthTalk, c/o E – The Environmental Magazine, Box 5098, Westport, CT 06881. Or: earthtalk@emagazine.com
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Comments
2. Mike Daly | 07.12.08
Why is there never any discussion on Oxo biodegradable technology? We all know there are shortfalls in Hydro (corn) technology; namely only works in controlled compost (113 sites in U.S. vs +15,000 landfills), emission of methane gas which is 23 times worse than CO2 and has to be 3-5 times higher than it’s replacement plastic.
Oxo technology is certified by ASTM6954 to work in compost, landfill and on land (as litter). While not tested, it will also work in our waterways; both fresh and salt).This technology uses an additive that can control how long before it degrades, so items can be recycled easily. There is no emission of methane gas. The release of CO2 is slower than Hydro products. The beauty is they just put an additive into plastic and dependant on the formula can control when an item breaks down with more effectiveness. The cost is minimal because you use plastic, plastic manufacturing with one step difference; cost increase is single digits over plastic. It seems to me this product will allow us to eliminate a problem with counter bags that are important to certain cities, foam cups, bowls, carryouts, etc that is important to other cities and ineffect would work on shrink wrap used by manufacturers and retailers in huge quantities, plastic packaging used by chip, candy,*******, cereals, bread, etc. Produced by the same facilities that make plastic now, there wouldn’t be any shortage of production or manpower as Hydro Technology.
All this seems so logical to me and the research is so easy to accesshttp://oxobio.org/ http://www.biodeg.org/available.htm Why aren’t we discussing this option?
3. Jacqueline | 07.12.08
Hey everyone. I think it is great that everyong can help out our environment. Just some small things have its advantages. I know this great company called GreenSak that sales recycled, cotton, grocery bags at a great price! Anything to help out Mother Earth.
4. Sarah | 12.20.08
Water News – Green Business Spotlight H2Om Water with Intention
Wow. After all of my internet surfing and blog posts, I finally came across a product that caught my attention. Just yesterday, I was browsing the bottled water section at Whole Foods when I came across a new brand with a really cool looking logo and labels that read “Joy”, “Peace”, “Health”, and “Prosperity” featuring instructions to visualize this intent while drinking the contents. Intrigued, I bought some and brought it home. It tasted fresher and cleaner than other waters - and hopefully my chosen intent (Prosperity, of course), will manifest.
Now, my curiousity was piqued even more so I chose to visit the company website. H2Om has a very interesting story to tell. The water itself comes from a natural spring water source in San Diego, from the 420,000 acre Cleveland National Forest. Bedrock mortars and metates indicate that Native Americans have enjoyed this spring for over 14,000 years - and it is filtered to a depth of 300 feet before rising to the surface through the hardened granite. The company then treats it with UV light, submicron filters it, and cleanses it with Ozone which is MUCH more efficient than chlorine at removing bacteria. The water is then treated with audio frequencies, sounds, music,color and light according to its intended purpose.
Scientific studies have shown that water is impressionable, and can hold intent or thought frequencies. As our bodies are 90% water, it makes sense to me that drinking this kind of water could have a positive impact.
Also from the company website:
“A portion of our proceeds will benefit the International Water for Life Foundation, the Love Planet Foundation, an environmental education organization dedicated to the protection of the planet for future generations.”
Awesome! And it was reasonably priced to boot.
It is refreshing to see that this Southern California company is leading the way and setting new standards in the bottled water industry while simultaneously inspiring people to participate in creating a better world by focusing their thoughts on creating positive intentions and eco awareness. So if you haven’t gone to the site while reading this, here is a rundown of H2Om Water with Intention.
What is H2Om?
H2Om is a natural spring water, no flavors or additives, bottled in a BPA-free PET1 bottle which is 100% recyclable. The positive themed labels are designed be used as a means to direct your focus towards creating intention. They serve as a reminder to activate your attention and create positive energy throughout your day.
H2Om’s commitment to you and the planet. First and foremost, H2Om has sourced the cleanest, most pure, high mountain spring water. (see my description above) The water emanates from a 4000 ft elevation and is naturally filtered through a granadorite rock formation. It is then brought down the mountain in a stainless steel transport vehicle, and ecologically filtered by UV light, sub micron filtration and then ozonated with Oxygen 3, the most healthy and natural way to clean water.
But wait… what about the plastic bottles? H2om’s BPA-free plastic bottle resin molds are manufactured in an eco-friendly hydro powered plant in Costa Rica, and the bottles are made locally in the US at their Los Angeles bottling plant. H2Om bottles contain no harmful chemicals that could leach into the water and are guaranteed to be Bisphenol-A and Phlalate free. The bottles are 100% recyclable, including the polypropolene labels. H2Om, in collaboration with it’s bottle manufacturer, is now testing the stability of an exciting new organic mineral that will be added to the plastic resin to break it down into nothing but water and oxygen after six months in the outdoor sunlight (coming soon). This will mean, whether in the ocean or landfill, the bottle will not contaminate or harm the environment. H2Om’s mission for sustainability is also represented by route managed deliveries, using tree free and 100% recycled papers and products, and having virtual offices, which are more energy efficient.
What about carbon emissions? In early 2007 H2Om became partners with CarbonFund.org. and was featured as one of their top 20 companies creating positive change on the planet while offsetting their entire carbon footprint. For more information on retail outlets or to order online visit http://www.H2OmWater.com
I am sort of a bottled water snob, but I do have this to say is, “I think this is a great product. The water tastes clean and pure. I actually followed the instructions and found some benefit to it. I also think it’s cool that the power of my purchase created some good on the planet, besides the good it did for me. Too bad there are not more companies following H2Om’s lead to educate, get people involved and be a part of creating something positive on the planet”
Try it out next time you’re in Whole Foods or your favorite health food market.
5. Tim Dunn | 01.22.09
There are a lot of problems with PLA - If we made all of the plastic disposable items used in the world every year, it would take one hundred million tons of corn to make it. That would lead to mass starvation in the third world, as that represents at least 10% of the world’s grain supply. Also, in landfills, PLA exudes methane when it decomposes-and methane is a potent greenhouse gas. It also takes a huge amount of diesel to grow, fertilize, ship, and process this corn. As a practical matter, it is also not recyclable. The alternative? Oxo-biodegradable plastics. See http://biogreenproducts.biz for full information. -Tim Dunn
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1. Jim Dodd | 07.11.08
Cargill does not produce or sell corn seed.