Maverick Enterprises
Biodegradable Plastics

CHOOSING A BIODEGRADABLE PLASTIC

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     When choosing the biodegradable plastic that you are going to use, you have to ask several questions in order to get the correct plastic:  how are you going to use the plastic? How is the plastic going to be stored and for how long?  Where this plastic product is going to be discarded so it will properly biodegrade?The following is a comparison of the positives and negatives of 3 biodegradable plastics .

 “Green Film”

 

 Positive

 1. Will biodegrade in landfills and as litter.
 2. Will compost (even in backyard composts).

 3.Will degrade if buried in a hole or in bodies of water.    
 4.
Can be safely recycled with regular plastics.    
 5.
Have no heat issues.    
 6.
Has no expiration dates.    
 7.
Leaves no harmful chemicals or metals behind after degrading.  8.Will not degrade when exposed to moisture.    
 9.
Will not break into pieces like oxy degradables. 
 10.When breaking down in landfills with anaerobic biodegradation, methane and water are produced. Although, uncaptured methane can contribute to global warming, according to the EPA, 75% of all the methane created in US landfills is being collected and then burned to create energy. It can now be money making project. Waste News, February 17, 2009. BMW in South Carolina is currently using methane from a nearby landfill to power their plant. Johnson and Johnson also does so. Methane is a cheaper source of energy at $.03-.045/kilowatt hour than windmills at $.11/kilowatt hour and solar power at $.60/kilowatt hour.    

 
Negatives:

1.Does not compost in 180 days as the required time period of ASTM 6400.
2.
Plastics other than polyethylene and polypropylene use petroleum. 70% of all plastics is the US (Polyethylene and polypropylene) use domestic natural gas for its development. Note: plastic bags use 1.5% of all the oil use in the US in one year. (US Energy Information Administration)    

Biobased corn products (PLA)

 

 

Positives:       

    1. Will degrade in commercial or municipal aerobic composting facilities in 180 days as required by ASTM 6400, but not in backyard composts or landfills. However, two commercial composters said that PLA and other ASTM 6400 utensils did not break down. They cited that the PLA  utensils needed to be crushed in order to compost. As they did not have the time or equipment to do so, they no longer accept PLA or products certified ASTM 6400.

Negatives:
  
1.Not sustainable- uses more fossil fuels than polyethylene as per “How Green are Green Plastics” in Scientific American”, Aug. 2000. The author states this belief on the cradle to cradle development of the product. Please consider the treatment of the soil before planting with a chemical, “Roundup”, which reportedly reduces the fertility of the soil; then the machine that plants the seed corn; then fertilization of chemicals; then the watering of the corn; then the harvest by machines; then the process where the corn is made into a finished product. NatureWorks’ website has an article that shows that their sustainability claims are based on buying renewable energy certificates. (“Sam's Club Partners with NatureWorks PLA to help the environment”, October 21, 2005.) Also this lack of sustainability is noted in Popular Science, Sept. 2007, where they state that one should not take “eco claims at face value. Companies may tout the value of natural fibers without mentioning some of the unnatural methods used to produce them. Take corn and bamboo for example. Both have the potential to be green, but environmental concerns remain.” “Concerns: Energy from fossil fuels goes into producing pesticides, herbicides and fertilizer for corn.”                        

          2.PLA will not degrade in landfills where most trash ends up. (NatureWorks tested their PLA using ASTM 5511 to prove this.) Normal plastics take 400 years to degrade in landfills. PLA which requires oxygen, moisture, and heat to degrade will probably last that long also. Landfills in the eastern US are nearly full and, according to the EPA, and PLA just adds to their filling up even quicker with their inability to break down in landfills.

  1. Can break down in temperatures over 110 degrees such as in trucks or warehouses. Thus they require storage in temperature controlled warehouses and being shipped in temperature controlled trucks using more energy. ("Smart care program describes how to handle PLA containers" from Packexpo, May 19, 2006) 
  2. Have expiration dates of about 24 months.
  3. Cannot be recycled with normal recyclable plastics. This has greatly affected plastic recyclers in the US according to articles in Plastic News.             
  4. There are only approximately 100 commercial and municipal compost facilities in the US, mostly in California and the Northwest-Oregon and Washington, so most biobased plastics do not end up in these sites where they can properly compost properly. According to an article in California "Ventura County restaurants have nowhere to send biodegradable tableware", March 20, 2009, illustrates the problem with PLA products. The restaurant owners wanted to do right by the environment by buying PLA products, but have no where to dispose of them so they end up in the landfill where they last as long as normal plastic- hundreds of years. 
  5. Because of the extensive growing of corn for PLA and ethanol, food costs have increased 10 to 13% according to the Dept. of Labor, for the year ending in June, 2007. The price of meat, cereal, chicken, pork, cheeses, flour, vitamins, and milk have leaped. Perdue and Smithfield Farms have both stated that the increase in cost of cattle feed has caused them to increase prices. Lance Foods announced on February 21, 2007 in an article in The Charlotte Observer, that there is less wheat being grown as farmers have switched to growing corn, thus increasing flour costs 30-40% in the last quarter alone.
  6. The extensive growing of corn and the heavy fertilizing it requires has polluted aquifers in the Midwest according to the Salt Lake Tribune. The aquifers were also being depleted with the heavy watering needed for corn.
  7. The nitrogen used in fertilizers for corn is also polluting rivers and the Gulf of Mexico. Corn requires heavy use of nitrogen in its fertilizing which has run off the fields into rivers and down the Mississippi into the Gulf of Mexico. This nitrogen feeds microscopic organisms that deplete oxygen levels as they die. The Gulf now has a dead zone 8,543 square miles according to Nancy Rabalais of the Louisiana University’s Marine Consortium. This area equals the size of New Jersey. And, unfortunately, this area is expanding. The dead zone has resulted in a 40% reduction in the number of licensed fishermen and shrimpers since 2001. The Chesapeake Bay has also been affected. (Taken from Bloomberg News, July, 2007 and the National Geographic, July 2008.)
  8.  According to life-cycle reports done by Franklin Associates in December, 2007, a HDPE container consumes less energy, produces less post-consumer solid waste, and generates fewer greenhouse gas emissions than containers made from corn-based PLA. (Please note: Franklin Associates have prepared many reports in the past for the EPA.)
  9. PLA/ethanol is creating more global warming pollution than gasoline according to the  Environmental Defense Org., November, 2007.
  10. GMO corn (found in most PLA products) kills the larvae of beneficial pollinators, including the Monarch butterfly, and other beneficial insects. It fails, for example, to kill the African Cotton Worm, but kills the beneficial Green Lacewing that eats Cotton Worms. Insects develop resistance to the engineered Bt toxin over time, threatening to render natural Bt sprays useless for organic farmers — a tool allowed as a last resort.
  11. GMO corn threatens organic farmers and a sustainable environment. Pollen drift and genetic contamination reduce biodiversity. (Packaging and Plastics, July, 2006, by Natalie Reitman-White and Bob Doppelt.
  12. A recent article from the World Bank states that 75% of the increase in food prices is because of corn used for biofuels. The US claims of 3% are way off. One would also have to include any corn based plastics as they are also using corn that would normally be used for food. The Guardian; July 4, 2008, Aditya Chakrabortty
  13. Smithfield Foods’ CEO C. Larry Pope, stated that the problems his company currently face are due to the high cost of corn, not to the recession. (Chapter 11 reorganization) “Profits are down because of the recession. We’d be doing fine if corn prices hadn’t skyrocketed.” The Virginia-Pilot, Feb. 12, 2009
  14. NatureWorks has been cited by the state of Nebraska for air pollution. They were guilty of emitting organic compounds (VOC) and hazardous air pollutants above the permitted levels- Plastic News, Dec., 2006.
  15. A Professor of Bio-polymers, Stephan Gilbert, states the use of certain bioplastics come with "unwelcome ethical consequences". Materials used to make bioplastics such as cornstarch and sugarcane are important sources of food. Using them for packaging is causing food costs to increase. Since some are not biodegradable in the soil and require special treatment for proper disposal, it makes little sense to use them in the first place. Food Production Daily, 2009.
  16. GMO corn fed to rats resulted in damage to several organs in the body: liver, heart, and lungs. (Natural Foods Merchandiser, Jan. 2010, “GM corn causes organ damage”. It only took 4 1/2 months for this damage to occur. This should raise red flags to consumers as the leaching that does happen with packaging, such as is the case of BHT, can happen with PLA. The study was published in the International Journal of Biological Science: “A Comparison of the Effects of Three GM Corn Varieties on Mammalian Health”, www.biolsci.org
  17. Germany’s Institute for Energy and Environmental Research stated in June, 2009, that oil-based plastics, especially recycled ones, have a better life-cycle analysis than compostable plastics. This is due to biobased plastics having “less favorable environmental impact profiles than other raw materials examined.”
                 Oxy Degradable Products 

Positives:
  1. Will degrade into pieces of plastic when exposed to sunlight, heat, or mechanical stress. (meets ASTM 6954-04)
  2. Good for countries with litter problems

 

Negatives:
  1. Will not degrade in landfills according to many studies including the one done by Loughborough University in 2009. It stated that evidence showed that it will not degrade in anaerobic conditions, such as those found in landfills. 
  2. While degrading, it separates into small pieces that can blow away before degrading completely thus polluting neighboring area. It could be eaten by animals, birds, or fish, which could kill them or greatly harm them by doing so.
  3. Will degrade when exposed to high temperatures in warehouses or on trucks.
  4. Come with expiration dates of approximately 12-24 months.
  5. Some oxy degradables leave dangerous chemicals such as cadmium in the soil after degrading.
  6. Germany’s IK Plastic Packaging Association states that oxy degradables do not meet biodegradability/degradability standards and will not longer be considered as such. (March 2006) As Germany is a leader in biodegradability, one cannot ignore such findings.  
  7. According to the Sydney Morning Herald, January 17, 2008, tests done on EPI oxy-degradable bags showed that they do not degrade any faster than normal plastic bags. It revealed heavy metals are the catalyst in making them degrade which are left behind. Environmentalists say this makes them potentially worse than regular plastic.
  8. Professor Gerald Scott wrote an article for bioplastics 03/09, after being asked to do so for Symphony Environmental Technologies, about oxo-degradables. In this article he states that oxo-degradables are not marketed for composting. He also states that they not designed for landfill biodegradation as it will not break down anaerobically (without oxygen) which is required for biodegradation in landfills. “It is intended to address the environmental problem caused by plastic waste which gets accidentally or deliberately into the open environment,” said Professor Scott. It does this by fragmenting into small pieces.