Plastics vs. Biodegradable PSM
Wednesday, August 20th, 2008Debby Harris from Richmond, BC writes:
We are a Richmond, BC company that has been producing and selling guestroom amenities (toiletries) to upscale hotels, resorts, airlines and cruise ships for 20 years. We have been concerned about the environment for numerous years. In fact, in 1998 we developed and patented a compartmentalized recycling basket called the "Waste-Not-Basket" to drive guest recycling in hotel rooms. These are now sold to over 200 properties throughout North America.
More recently, we have been introduced to a new material called PSM (or Plastarch), a biodegradable product made from cornstarch resin. Today it is being produced for products such as shower caps, utensils, golf tees, garbage bags, toothbrushes, etc. However, we are concerned about its ability to biodegrade in landfills, and certainly don’t want to produce more methane gas or other noxious emissions than if we continued providing recyclable plastic bottles for our amenity programs.
Can you guide me to an authority on plastics who can give us the straight-goods on PSM and other biodegradable materials? We certainly want to contribute to improving our environment and value your opinions.
Lindsay replies:
Your business initiative to get hotels and others recycling sounds great. There are quite a few hotels that market themselves as "green" for this very reason. With respect to your question on bioplastics, it’s a good one, although not something the Foundation has researched. I can give you some information to get you started and then you’ll need to do a bunch more reading and asking around.
Issue 1: Using cornstarch or soy instead of petroleum to make plastic uses 3-4 times less Co2, and the production uses about 68% less fossil fuels.
Issue 2: Most bioplastic bags, containers, etc. won’t biodegrade under the conditions of a backyard composter. You’d have to quiz your supplier about this in detail. How biodegradable is it? How long does it take? Can people put it in their home composter or does it need to go to a specific facility? For instance, I’ve seen claims that one product that was 100% compostable and biodegradable breaks down within 3-6 months in a commercial composter or 4-5 months in a home composter. How long will they take to breakdown in a landfill is unknwon.
Issue 3: Cornstarch-based bioplastics can be made from GMO (Genetically Modified Organism). Half the corn grown in the U.S. is GMO. This is yet another layer.
It sounds like you need to find out how long these materials take to break down in a typical landfill, unless you’re certain they will go to a specific composting facility. Best of luck with your quest!