Greenhouse Gas Impact of Styrofoam Trays

A few people asked me to post what we learned about Styrofoam trays. Here is some of the information, although I did not get a specific answer to my question. I was not able to find any calculators, or reliable information for how much GHG is reduced by eliminating disposable Styrofoam lunch trays without a weight. On Friday I did run across the EPA's model, but needed the weight. It also didn't have the option to enter "tons reduced" for mixed plastics. (http://epa.gov/climatechange/wycd/waste/calculators/Warm_home.html) I also came across a few facts located within some scientific reports about polystyrene. It looks as though these reports were written within the polystyrene industry. These are the ONLY sources that I was able to find that mention any specifics about the amount of GHG produced by polystyrene. *Expandable polystyrene typically contains between 3-7% by weight of pentane. Consequently, the manufacturing of 1000 pounds of expanded polystyrene could emit 30 to 70 pounds of pentane. (http://www.huntsman.com/polymers/Media/TEC_I_002.pdf) *Estimates from these literature sources show that between 90 and 420 kilogram-equivalents of carbon dioxide are produced from each kilogram of material (polystyrene/plastics) through the degradation process. This increase in carbon dioxide release can significantly affect the GHG production in sensitive areas such as southern California (Krause 2006) (www.smgov.net/cityclerk/council/agendas/2006/20061205/s2006120507-D-3.p df) I decided to look up polystyrene tray providers online to see if I could find an approximate weight. At Pactiv, I found that 500 trays weigh 13.5 pounds. That would mean that each tray weighs approximately .027 pounds; and that 150,000 trays (those not used at ISD) would total about 4,050 pounds of polystyrene, just a little over two tons. Based on the facts above, that would mean that the manufacture saved 120-280 pounds of pentane from being produced. Since 4,050 pounds is equal to about 1,840.9 kg that would mean that 165,681-773,178 kg of C02 from the degradation process were not released through the degradation process of 150,000 lunch trays.

For future reference, Portland Public Schools did a report called "Environmental Costs and Benefits of Switching from Polystyrene Disposable Ware to Polycarbonate Permanent Ware". You can purchase it for $2 by contacting Renn Harris, Supervisor, Environmental Services, Portland Public Schools, PO BOX 3107, OR 97208; (503)249-2000. Here is a small portion of what it discusses: A study by the Portland, Oregon, public school system concluded that switching the school system from polystyrene to reusable polycarbonate foodware would, over a five-year period, save 11 billion BTUs of energy. It would prevent 248,000 pounds of solid waste and 60,000 pounds of airborne emissions (chiefly, pentane, a greenhouse gas and contributor to smog, and sulfur dioxide, and acid rain pollutant). It would increase water consumption by 10,600,000 gallons and produce 39,500 pounds of waterborne waste. The amount of water used, equivalent to the domestic consumption of 38 households, could be reduced with water-efficient washing machines. (http://www.ejnet.org/plastics/polystyrene/nader.html ) If this will come up again, it might be worthwhile to contact them and get a copy to learn what method they used for getting those figures. Avoiding Use of Styrofoam Trays: The following information came from a PowerPoint that can be found at: http://www.ereciclaje.com/cultura/Styrofoam%5B1%5D.ppt called "Cradle to Grave: The Life Cycle of Styrofoam" Even by reducing Styrofoam use, the best option is to avoid the manufacture and use of Styrofoam all together. Here are a few reasons why: The chemical components that make up Styrofoam are bad for our health. Benzene is the most toxic of the chemicals used to produce Styrofoam and it is listed on the Hazardous Substances list. It is thought to lead to cancer as well as a number of other health related problems. You can't get rid of Styrofoam. It takes over 500 years to dissolve, and while it is lightweight it still represents 25%-30% of landfill space nationwide. There are very few recycling centers and the state of WA doesn't have one. Transporting Styrofoam products creates a lot of GHG. Due to the locations of production plants over 80% of the US gets its Styrofoam from over 500 miles away. That results in C02 emissions from freight trucks and oil-to-groundwater seepage pollution.