JESSICA STANDLEY NATHAN JAMES BO XIAO CARBON NEUTRALITY UNST 421 SPRING 2010 THE PLASTIC BAG

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1 JESSICA STANDLEY NATHAN JAMES BO XIAO CARBON NEUTRALITY UNST 421 SPRING 2010 THE PLASTIC BAG PROJECT Our group challenged itself to find a way to reduce disposable bag usage on the Portland State campus. We researched the usage of disposable bags at select retailers and researched the carbon emissions from these bags from production and transportation. Based on our research we came up with a proposal to reduce the usage of these disposable bags. Lastly, we surveyed Portland State students on usage and possible effects of our proposal. INTRODUCTION What are plastic bags; a convenience, a nuisance, a problem, dangerous? They are all of the above. They were made for convenience, they are now and nuisance because of the unbelievable numbers that are used and produced per year. They are a problem because they take nearly 1000 years or more to break down and they also require the use of petroleum, crude oils, and natural gases which are non- renewable resources 1. And they are dangerous for our environment because of the energy and carbon emissions they make during the production and distribution. They also are responsible for over 100,000 sea turtle and other marine animal deaths. These animals ingest them because they mistake them for food and they get entangled in them because these bags are flooding their waters 2. HISTORY The shopping plastic bag first made its way into our life for convenience when retailing stores like JC Penny and Sears switched to plastic merchandise bags in 1974 after the first commercial manufacturers for the plastic grocery bag was introduced in Shortly after, the plastic bags began to be used in grocery stores. The plastic bag didn t just appear out of nowhere. It all began in 1957 when bags for small foods and sandwiches were introduced. In 1958, the brown paper bag was beginning to be replaced by plastic poly dry cleaning bags. In 1966, the plastic produce bags were introduced into grocery stores 1. NUMBERS What began with small numbers has now turned into a mind blowing over 500,000,000,000 (500 billion) plus plastic merchandise, grocery, and biodegradable bags used annually worldwide. That is over 1,000,000 used per minute. Some of the biggest culprits are Australia and Ireland per capita. Before they began to make changes and fix the problem it was said that the average in these countries were using around 320 bags per person 2. Americans are around 200 per person 3. TYPES Petroleum, crude oils, and natural gases are extracted from the earth and used for the production of polyethylene. Polyethylene is than used to make plastic bags. Some types and their uses are: LLDPE: Merchandise bags(not grocery), plastic sheets, toys 4 LDPE: Packaging wraps, containers 5 HDPE: Grocery bags, bottles, plastic lumber, PVC 6 Biodegradable plastics are another option for plastic bags, bottles, packaging wraps, containers 7. They are produced with starches and polymers which are earth friendly. They take 9 months to five years to biodegrade and this process does not leak toxins into the earth like plastic. Carbon is emitted during the production phase of the ingredients, and distribution, but there are no carbon emissions during the biodegrade stage 8.

2 PRODUCTION It takes 1.75 kg of petroleum to make 1 kg of HDPE which makes 167 bags grocery bags. This same amount of petroleum used will make 0.3 kg of LLDPE or LDPE which makes around 55 bags. This is enough petroleum to power a car for 12 miles 11. With the amount of bags made per year, if we were to stop the production of the bags all together, it would be enough petroleum to power cars for around 50,560,696, (billion) miles per year. If 1.75 kg of petroleum will make 167 HDPE and power a car for 12 miles, then the amount of petroleum used to make 400,000,000,000 (amount assumed) HDPE bags will power a car for 28,742,514, miles. And the amount of petroleum used to make 100,000,000,000 (amount assumed) LLDPE bags will power a car for 21,818,181, miles. TRANSPORTATION The transporting of these bags is another reason why the bags are dangerous for our environment. According to a LCA (Life Cycle Analysis) done in 2002, 67% of HDPE bags are coming from Hong Kong, 34% of LDPE and LLDPE are coming from Hong Kong, and 100% of biodegradable bags are coming from Italy 9 (the numbers of manufacturers for biodegradable bags have increased since this study). These numbers means that some bags are traveling around 7000 miles just to get to us in America. END OF LIFE At the end of the life of the plastic bags is the worst part of the problem with the plastic bag. For the plastic grocery bag, they are able to be recycled at local grocery stores. These are than used for the making of plastic lumber and more plastic bags, but only 1-5% of these actually make it to the grocery stores for recycling 10. The LLDPE and LLDPE bags do not have a recycling program. They are just thrown away. The LCA done in 2002 brings the end of life assumptions into perspective 9 : HDPE 75.5% in landfill 1-3% recycled.5% littered 19% reused LLDPE/LDPE 80.5% in landfill 0% recycled.5% littered 19% reused BIODEGRADABLE 70.5% in landfill 10% compost.5% littered 19% reused PORTLAND STATE UNIVERSITY At Portland State University the Biodegradable bags are being used at both the Student store and the Green Line store on campus. At the Bookstore, they use the LLDPE because of its thickness and ability to carry extra weight. Here are the locations of the distributor and manufacturers of the bags used at PSU. 12 Green Line: - Use approx. 10,000 to 20,000 biodegradable bags per year - ECM Biofilms Located in California and manufactured in Ohio - Ohio to California = approx. 2,000 miles - California to Oregon = approx. 800 miles 13 Student Store: - Use approx. 3,000 biodegradable bags per year - Trellis Earth bags Located in Portland and manufactured in China - China to Oregon = approx. 7,000 miles 14 Book Store: - Use approx. 50,000 to LLDPE bags per year

3 - Roplast Industries Located and manufactured in California (800 miles) CARBON EMISSIONS OF PLASTIC BAGS According to, Time for Change 16, for each kg of Polyethylene produced, 6kg of CO2 will be emitted (2kg of oil for energy and raw material, and for each kg of oil creates 3kg of CO2). In order to determine the amount of CO2 emitted for the production of the LLDPE bags used at PSU we look at information stated earlier which said that 1kg of petroleum will produce 0.3kg of LLDPE and this will make around 55 bags. The PSU bookstore uses 50,000 bags per year. If 0.3kg of LLDPE = 55 bags than kg of LLDPE = 50,000 bags x 6 = kg ( lbs) of CO2 emitted /0.3 = 909.1kg of petroleum used According to, ECM Biofilms 12 website, only during the production phase of the corns and starches do their bags produce any carbon emissions. This is not totally truthful. They fail to mention how much energy is used for packaging and transportation. Ton mile is a term that is used by Carbon Fund 15 which states that a ton of freight traveling one mile is a ton mile. This term is used to determine the amount of CO2 that is being emitted for a type of transport. Air Cargo = lbs of CO2 per TM Truck = lbs of CO2 per TM Train = lbs of CO2 per TM Sea Freight = lbs of CO2 per TM Zeppelin = lbs of CO2 per TM According to Sustainability Victoria, the weight in grams of the LLDPE is 18g and 5g for the biodegradable bags. With the miles we have for travel and the weight of the bags without the information of the package material, we can get a rough estimate of the carbon emissions of just the transportation of plastic bags for PSU. We can assume this is a one trip transaction and the only thing being hauled. Bookstore: 50,000 LLDPE bags traveling 800 miles, assuming by truck. 50,000 x 18g = 900,000g this is lbs (1 ton) Truck travel emits lbs of CO2 per TM. 800miles x = 260 lbs of CO2 emitted. Greenline: 3,000 bio bags traveling 2,800 miles. 2,000 by plane, 800 by truck. 3,000 x 5g = 15,000g this is lbs (0.015 tons) Plane travel emits lbs of CO2 per TM. 2,000 miles x = lbs of CO2 multiplied by because the weight was less than a ton x = lbs of CO2 emitted 800 miles x = 260 x = 3.9 lbs of CO2 emitted = lbs of CO2 emitted. Student Store: 10,000 to 20,000 bio bags traveling 7,000 miles, assuming by plane. 10,000 x 5g = 50,000g this is lbs (0.05 tons) Plane travel emits lbs of CO2 per TM. 7,000 miles x = 12,417.3 lbs of CO2 multiplied by 0.05 because the weight was less than a ton. 12,417.3 x 0.05 = lbs of CO2 emitted. If 20,000 bags than lbs of CO2 emitted. ~Assumption with sea freight: 50,000g (0.05 tons) Sea freight travel emits lbs of CO2 per TM.

4 7,000 miles x = 60.9 lbs of CO2 multiplied by 0.05 because the weight was less than a ton x 0.05 = lbs of CO2 emitted. If 20,000 bags than 6.09 lbs of CO2 emitted. Carbon Emissions from Plastic bags The biodegradable bags from the Student Store in the Smith Building are manufactured in China, while biodegradable bags from the Green Line are made in Ohio. The Student Store consumes an average of 15,000 bags annually. The Green Line just opened in January and has uses about 250 bags each month. Thus, the projected annual usage of bags is about 3,000. The annual consumption of bags for both stores is total 18,000. Since the weight of bag is 5 grams, then the total number of bags in pounds both stores use is each year. According to a study by Center for Design at RMIT University in Australia, 4.96 kg of carbon dioxide emits through the usage of electricity and fuel in order to produce 4.21 kg of starch- polyester 17. By assuming a linear relationship between carbon dioxide emission and the consumption of bags, the carbon emission for both stores is 234 lbs per year. Nitrous oxide releases in the growing process in the crops and methane emits in landfill, however; both emission of nitrous oxide and methane is a small fraction of total green house gas compared to carbon dioxide 18. Although the components of biodegradables bags (made in Italy) in Australia may be different than the one both stores currently use (made in China), the larger fraction of green house gas is still carbon dioxide in both cases. Table 1 The respective number of carbon emission of bags for each store due to production Student Store +Green Line Book Store Total Figure 1 Annual carbon dioxide emission of bags during the production process In Figure 1, Book Store has the most the carbon emission of bags due to production (3607.b lbs) while the combined carbon emission of Student Store and Green line is only 234 lbs per year. First, the plastic bags of Book Store are LDPE that needs

5 more energy to production and results in more carbon emission, while both Student Store and Green Line use biodegradable bags which are made from starch- polyester and results in less carbon emission. The total annual carbon emission for three stores is lbs. Table 2 The carbon emission of bags due to transportation for three stores Green Line Student Store Book Store Total Figure 2 Annual carbon dioxide emissions of bags due to transportation phase. In Figure 2, Green Line has the least amount of carbon emission due to transportation (57.31 lbs). Book Store comes in second with 260 lbs and Student Store has the highest amount of carbon emission ( lbs). The total carbon emission for three stores is lbs. The biodegradable bags (15,000) of Student Store are purchased from a company called Trellis Earth who obtains the bags from China 19. Thus, it take a very long flying mileages (7,000 miles) The bags of both Green Line and Bookstore(53,000) are manufactured in the U.S and are most by truck and part of it by airplane, which has short traveling mileages. Table 3 The total carbon emission of bags for the stores Production Transportation Total Figure 3 Total carbon emissions for three stores each year.

6 In Figure 3, the production of bags emits lbs carbon dioxide while the transportation of those bags results in lbs carbon emission. The total carbon emission for three stores is lbs each year. One reason the carbon emission due to production is more than the transportation is that the number of bags of Book Stores use each year is 50,000(3 times of more bags than the other two stores) and LDPE. IMPLEMENTATION OF CHARGE FOR BAGS IN OTHER PLACES In Washington, D.C. starting this year a five cent fee was placed on disposable bags. In the first month, estimated bag usage went from an estimated 22 million per month to an estimated three million. 20 We propose implementing a similar fee at the Student Store, Green Line Market and the Portland State Bookstore. SURVEY A survey was conducted with 100 students as follows: Do you use plastic bags from the bookstore? If no, what do you use? Back pack, tote, arms, shoulder bag? (finished) If yes, would you continue to use the bags if you had to pay $0.05 for them? (continue) How many bags would you say you use per term? What do you do with the bags after you are done with them? Reuse for trash liner Throw away into trash Litter Other Results: (26,000 students enrolled) 62% claim to not use bags (16,120 students) o 50% use backpacks o 19% use totes o 19% carry books and supplies o 12% use shoulder bags 38% of students at PSU use bags and with an average of 2 bags per student used per term (6 per year). Calculated out, this is in line with known usage. Our survey numbers calculate out to approximately 59,280 bags per year used at the bookstore. 44% of students could pay the $0.05 and continue to use the bags

7 56% of students claim they would discontinue their use which would decrease the amount of bags used down to 26,083 bags per year. Disposal after use shows: o 37% reuse as trash liner o 31% throw away o 13% reuse for cat litter o 13% reuse as bags o 6% recycle o 0% litter POSSIBLE CHANGES FOR PSU WITH CHARGE Based on the survey, the proposed fee would lead to a reduction of disposable bag usage down to approximately 26,000 per year. The fee would generate $1,300 dollars annually that could go towards funding carbon saving projects Carbon emissions from disposable bag usage from these retailers would drop by more than half PATH TO IMPLEMENTATION The Student Store in Smith has a contract with ASPSU. ASPSU negotiates retailer contracts every two years and could implement the fee. The Green Line Market could choose to implement the fee internally. The Portland State Bookstore is a private non- profit. It too could choose to implement the fee internally.

8 1 Packaging Knowledge Reusable Bags. The numbers Believe It or Not. 3 This is Money. The Life Cycle of a Plastic Bag. Daily Mail: February 27, density_polyethylene 5 density_polyethylene 6 density_polyethylene Nolan- ITU Pty Ltd. Biodegradable Plastics Developments and Environmental Impacts. ExcelPlas Australia: October publications/waste/degradables/biodegradable/chapter1.html 9 Sustainability Victoria. Comparison of Existing Life Cycle Analysis of Shopping Bag alternatives. Report #1. Page 10,11. Table 3-2. April 18, Reusable Bags. Recycling Can Fix it Right? 11 Nekton Bot. What is HDPE? Sonayi Ve Ticaret a.s ECM Biofilms Trellis Earth Roplast Industries Inc Time for Change. Plastic bags and plastic bottles CO2 during lifetime. Juerg. bags- and- plastic- bottles- co2- emissions 17,18 James, Karli., and Grant Tim (2005). Retrieved May 31, 2010, from 19 Trellis Earth (2010). Sustainability. Retrieved May 31, 2010, from 20 Craig, Tim (2010). Retrieved May 30, 2010 D.C. bag tax collects $150,000 in January for river cleanup dyn/content/article/2010/03/29/ar html?sub=ar