A Comparative Life Cycle Analysis of Plastic and Paper Packaging Bags in the Philippines

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1 A Comparative Life Cycle Analysis of and Packaging Bags in the Philippines * Jose Bienvenido Manuel M. Biona Mechanical Engineering Department, Center for Engineering and Sustainable Development Research (CESDR), De La Salle University, 2401 Taft Avenue, 0922 Manila, Philippines jose.bienvenido.biona@dlsu.edu.ph Aristotle T. Ubando Mechanical Engineering Department, Center for Engineering and Sustainable Development Research (CESDR), De La Salle University, 2401 Taft Avenue, 0922 Manila, Philippines aristotle.ubando@dlsu.edu.ph Jeremias A. Gonzaga Mechanical Engineering Department, Center for Engineering and Sustainable Development Research (CESDR), De La Salle University, 2401 Taft Avenue, 0922 Manila, Philippines jeremias.gonzaga@dlsu.edu.ph Hazel Claire Tan Center for Engineering and Sustainable Development Research (CESDR), De La Salle University, 2401 Taft Avenue, 0922 Manila, Philippines tanhaste@gmail.com Abstract Various cities in the Philippines have started to prohibit the use of plastic bags and packaging materials in favor of paper products for waste disposal and management reasons. This study evaluated the soundness of these initiatives based on life-cycle analysis (LCA) framework. While a number of studies have looked at similar issues in other countries, results may not be entirely valid in the Philippines due to different variations in energy and material supply chain and waste disposal practices and system. Considering the usual products being purchased by a Filipino family and the amount, 12 liter sando bags and 14 liter paper bag capacity were used as the functional units for the research. Comparison of the impact assessment was done by looking into the cradle-to-grave processes of the two bag materials. The study covered disposal to land, air and water effluents and included the global warming, acidification, ozone depletion and human toxicity impact areas. A modified EDIP was used for the life-cycle inventory and results show that out of the four impact factors, three favored the use of plastic bags. Future studies may be done on other impact factors as well as on other bag materials. This study was commissioned by the Department of Environment and Natural Resources (DENR) to aid policy development in waste management in the country. Keywords Life Cycle Assessment, Philippines, bag, bag, Waste Management I. INTRODUCTION s and polystyrene foams are widely used as packaging in the Philippines. Due to their imperviousness to water, plastics and polystyrene foams have become the preferred materials for use in different establishments like groceries and restaurants. Though easy to manufacture and are quite versatile, their applications after disposal pose a problem as decomposition of such materials takes centuries. In a waste analysis characterization survey (WACS) conducted on March 2009 in Payatas, Quezon City, Philippines, it was found that the approximate generation of residuals in that major city in Metro Manila was about 248 tons per day. Of these residuals, 62% were plastic sando bags [1]. This is just one of the many major cities in Metro Manila and estimating the total consumption of the whole country, it can be said that a good amount of plastics are being disposed of in landfills every day. In 2011, the Senate Bill No [2] on the Total Bag Ban Act was passed into law, prohibiting the sale, distribution, and use of plastic bags in groceries, restaurants, and other establishments. Compared to plastics, paper products are more environmentally friendly as they are made of natural materials which are also easily degraded or recycled. However, considering the usage now that paper packaging is replacing plastic packaging, it is definite that there is some form of impact on the environment for this usage. In order to fully understand these impacts, life cycle assessment (LCA) was conducted. LCA is an internationally standardized method in assessing the environmental effects of processing of products from cradle to grave [3]. What makes this method ideal is that it provides a systems approach to examining the environmental impacts of certain materials and information obtained allows for a wider perspective in viewing the overall environmental issues involved [4]. Many studies have already been done using the LCA method in other countries to guide the government in policy making [5]. Previous LCA study was conducted for the evaluation of supermarket carrier bags in the United Kingdom [6]. However, the results are not valid for the Philippine setting as the raw material and energy sources vary from one country to another. In this study, the impact of different packaging materials in the Philippines was determined using LCA. Analysis took into account the energy

2 and material inputs compiled from the different stages of production and disposal. Data obtained was used to determine the life cycle impact assessment of the different packaging products using the Environmental Design of Industrial Products (EDIP) method. A modified impact factor was used to include the different conditions with which the disposed materials are exposed to. Limitations to this study include the use of only two types of packaging materials, specifically, plastic sando bags, and paper. In addition, discharge standards for certain chemicals related to production are based on data obtained from other countries due to unavailability of local discharge standards. Results obtained in the study would provide a better perspective on the actual impacts of each packaging material which may guide the legislative in the waste management policy development in the country. II. LIFE CYCLE ASSESSMENT METHODOLOGY The functional units of this particular study were 12 liter sando bag and 14 liter paper bag capacity. These functional units used in this particular study were based on the amount of material to carry a similar set of goods while the composition were considered based on the commonly purchased goods of a Filipino family. In order to identify clearly the areas that are covered in plastic and paper packaging material LCA, a system boundary was specifically established. The different processes from cradle-to-grave for plastic packaging material is shown in Fig. 1 while for paper packaging material is shown in Fig. 2. Each of the process found in Figs. 1 and 2 accounts for the consumption of fuel and electric, and the emissions generated for both paper and plastic bags. The carrier bag raw material supply shares for local and imported materials are shown in Table 1 for plastic bag and Table 2 for paper bag. In this case study, recycling was not considered to isolate the impact of virgin production for both plastic and paper bags. A threeleveled material and energy source framework was adapted as shown in Fig. 3 to account the fuel and electricity consumed together with the emissions generated during the pre-bag production processes for both plastic and paper. The three levels of material and energy sources represent the regions where the raw materials originated based from MIT supply chain mapping website [7]. Level 1 represents the Philippines where the raw materials were shipped for the bag production. Level 2 represents the countries where the raw materials were manufactured such as: polyethylene for plastic bag and pulp for paper bag. Level 3 represents the raw material extraction and preparation for plastic bag, and farming and wood production for paper bag. Since each level came from a different country, the fuel consumed to transport the raw materials were calculated based on the shipping distance of each of the countries involved from Sea-Distances.Org [8]. For shipment of raw materials through land and pipe transmission, the distances were acquired from Google Maps [9]. Recycled Crude Oil Refined Petroleum Raw Material Extraction Raw Material Preparation Monomer Ethylene Polyethylene Bag Distribution Waste Transportation Polymer Bag Natural Gas Processed Natural Gas Fig. 1 bag cradle-to-grave process flow. Landfill Thrown in wastewater Burn at site Composted at source The country source of raw materials and energy were categorized into its location based on the seven regions South East Asia and the Pacific, East Asia, South and Central Asia, Europe, North America, Latin America and Caribbean, and Middle East and North Africa. The prorated distances from level 3 to level 2 countries for each raw materials and energy were calculated from these equations: y T = Σy (1) y / y T = n (2) D n = P (3) P T = ΣP (4) where y is the amount of shipped raw materials/energy fuel, y T is the total shipped raw materials/energy fuel, n is the normalized shipped amount for a given raw materials/energy fuel, D is the shipping distance from the source country to the receiving country, and P is the prorated distance of a given raw materials/energy fuel at a combination of source and receiving country, P T is the total prorated distance for a given region..

3 Seed plantation Farming Wood Wood Recycled Pulp Pulp Sheet Bag Distribution Waste Transportation Bag Fig. 2 bag cradle-to-grave process flow. Landfill Thrown in wastewater Burn at site Composted at source Table 1. bag raw material supply share. Bags Raw Materials Local Imported Supply Share Refined Petroleum 100% 0% Processed Natural Gas 100% 0% Ethylene 44% 56% Polyethylene Resins 29% 71% Recycled Resins/Bags 100% 0% Bag 100% 0% Table 2. bag raw material supply share. Bag Raw Materials Local Imported Supply Share Recycled Pulp 50% 50% Virgin Pulp 0% 100% Sheet 10% 90% Bag 90% 10% Level 1 Level 2 Regions Sources of materials & energy Level 3 Regions Sources of materials & energy Fig. 3: Framework of Philippine raw material and energy sources. The objective of this study is to determine the life-cycle environmental impact of plastic bag and paper bag using LCA methodology. Due to limited information on the actual lifecycle inventory (LCI) of the both plastic and paper bags in the Philippines, the LCI used in this study was based from Franklin Associates [10]. This information was then used to determine the LCA of plastic bag and paper bag using Environmental Design of Industrial Products (EDIP) 97 [11, 12]. A modified EDIP 97 was utilized in this study which covers emission related impacts and resource consumptions such as global warming potential, acidification, ozone depletion, human toxicity, and photochemical ozone creation. The global warming potential represents the equivalent carbon dioxide (CO 2 ) emissions from the combustion of fossil-based fuel of the whole production chain of the bags. The CO 2 emissions are directly related to climate change impact such as global warming potential (GWP) [13]. The acidification impact category represents the equivalent sulfur dioxide (SO 2 ) emissions from the combustion of fossil-based fuel of the whole production chain of the bags. Acidification signifies an increase in hydrogen ions (H+) delivered to a specific medium which causes change in its ph causing damage to the organic and inorganic material [13]. The ozone depletion potential represents the release of substances having the same effect as chlorofluorocarbon (CFCs). CFC-11 was chosen in EDIP 97 as a representative substance for other similar substances due to its large contribution to ozone depletion [13]. Human toxicity signifies the kg 1,4 dichlorobenzene (DCB) equivalent which are heavy metals emitted during the production of bags. The assessment of human toxicity is the measure of tolerable daily intake of such substances [14]. Lastly, photochemical ozone creation (POC) corresponds to the smog generated due to the emissions of nitrogen oxides (NOx) and other volatile organic compounds (VOCs). POC is expressed in terms of kg ethene (C 2 H 4 ) equivalent [15]. To compare the impact assessment of plastic and paper bags, the cradle-to-grave processes of the two

4 bag materials were simplified to five phases: 1) raw material extraction, 2) raw material preparation, 3) bag production, 4) utilization, and 5) disposal. For plastic bag, the raw material preparation phase consists of the raw material preparation, monomer production, and polymer production as indicated in Fig. 1. For paper, the raw material extraction phase consists of farming and wood production while the raw material preparation phase consists of the pulp and paper production as shown in Fig. 2. The transportation of the paper and plastic bags from the production sites to the distribution market were considered. The disposal method and its percentage considered in the study are shown in Table 3 [16]. Normalization of impact category and its weighing factor were not included in this study. Table 3. method considered. Method Bag Bag Disposed to Landfill/Dumpsite 83% 85% Buried in Pit 4% 3% Thrown in Waterways 5% 5% Burned 8% 7% III. RESULTS AND DISCUSSIONS The results of the comparative analysis between plastic and paper bags are shown in Figs. 3 to 6. The lower the value of the impact factors the lower the impact to the environment, which is the preferred result. In Figs. 3 and 4, the global warming potential and acidification clearly illustrates that plastic bag sounds more environmentally friendly compared to paper bag. Since paper bag requires fertilizer during the farming and plantation stage of trees, it has higher GWP. In addition, the GWP of the raw material preparation and the production phase of paper bag are much higher compared to the plastic bag by 2.48 times. For acidification, the presence of SO 2 equivalent emissions are seen in the raw material extraction for paper bag compared to plastic bag. In addition, higher acidification effects were seen for both raw material preparation and production phases for paper bags compared to plastic bags. The acidification impact of plastic bag is 2.49 times higher compared to paper bag. However, an analysis for a 20 year effect revealed that paper bag has no ozone depletion impact compared to plastic bag. Even though the ozone depletion impact of plastic are relatively lower compared to other impact factors having a magnitude of 10-12, paper bag is preferred in this impact factor with zero magnitude. A 20 year effect on human toxicity revealed that paper has greater impact compared to plastic bag especially by about 2.46 times. Just like in GWP and acidification impact category, human toxicity is relatively present in the raw material extraction phase for paper bag while minimal effects were seen in for plastic bag. Lastly for photochemical ozone creation, paper bag has adverse environmental impact compared to plastic bag by 2.48 times. Similar to GWP, acidification, and human toxicity, the photochemical ozone creation for all of the stages of paper bag production is relatively high to plastic bag. 2.50E E E E E E E E E E E E E E E E E E E E-13 Global Warming Potential (kg CO 2 eq./kg) Raw Material Extraction Fig. 3. Global warming potential comparative result. Raw Material Extraction Acidification (kg SO 2 eq./kg ) Fig. 4. Acidification comparative result. Ozone Depletion (20 yrs.) (kg CFC 11/kg) Raw Material Preparation Raw Material Preparation Raw Material Extraction Raw Material Preparation Fig. 5. Ozone depletion comparative result.

5 2.50E E E E E+00 Human Toxicity (20 yrs.) (kg 1.4- DCB eq./kg) Raw Material Extraction Raw Material Preparation Fig. 6. Human toxicity comparative result. Photochemical Ozone Creation (kg ethene eq./ kg) 1.80E E E E E E E E E+00 Raw Material Extraction Raw Material Preparation Fig. 7. Photochemical ozone creation comparative result. The impact of the utilization and the disposal phases were relatively minimal for all impact categories for both materials. Four out of five impact factors favored the use of plastic bags over paper bags. The results of this study shall aid policy makers in the Philippines to revisit the Total Bag Ban Act of IV. CONCLUSIONS A comparative life-cycle assessment was conducted to evaluate the impact performance of plastic and paper bags in the Philippines. A global supply chain specifically for the Philippines was developed and utilized to assess the impact of the raw materials and energy from cradle-to-grave. A modified EDIP was used for the life-cycle inventory of the comparative study. The results revealed that plastic bag has lesser environmental impact compared to paper bag based on global warming potential, acidification, human toxicity impact, and photochemical ozone creation categories. The results of this study shall aid policy and decision makers in the Philippines to revisit the Total Bag Ban Act of Future works involve the inclusion of the non-woven polypropylene bags in the analysis together with adding impact factors such as eutrophication, photochemical ozone, fresh water and marine ecotoxicity in impact assessment. Recycling of bags, prioritization weights of impact factors, and uncertainty analysis shall also be included in future studies. ACKNOWLEDGMENT The authors would like to acknowledge the DOST-IDTI and Department of Environment and Natural Resources (DENR) for funding this research. REFERENCES [1] A.M. Monsada. Waste s Recycling Technologies in the Philippines. UNEP-AIST Workshop on Waste s Management, March 01-04, 2011, AIST Tsukuba Center, Tsukuba City, Japan, Accessed on October 1, Workshop%20in%20Tsukuba%20March%202011/11_Waste Recycling_Philippines.pdf [2] Senate Bill No on the Total Bag Ban Act of 2011, Philippines, Accessed on October 1, [3] R.R. Tan, A.B. Culaba, M.R.I. Purvis, J.Q. Tanchuco. Life Cycle Design, Planning, and Assessment. Web-Based Green Products Life Cycle Management Systems: Reverse Supply Chain : pp Information Science Reference, New York, USA, [4] C. Chaffee, B. Yaros. Life Cycle Assessment for Three Types of Grocery Bags - Recyclable ; Compostable, Biodegradable ; and Recycled, Recyclable. Boustead Consulting & Associates Ltd, Accessed on October 1, [5] P. Roy, D. Nei, T. Orikasa, Q. Xu, H. Okadome, N. Nakamura, T. Shiina. A review of life cycle assessment (LCA) on some food products. Journal of Food Engineering 90(1): p. 1-10, [6] C. Edwards. Life Cycle Assessment of Supermarket Carier Bags. Environment Agency, Horizon House, Deanery Road, Bristol, BS1 5AH, Accessed on October 1, ment_data/file/291023/scho0711buan-e-e.pdf [7] A.J.G. Simoes, C.A. Hidalgo. The Economic Complexity Observatory: An Analytical Tool for Understanding the Dynamics of Economic Development. Workshops at the Twenty-Fifth AAAI Conference on Artificial Intelligence, Accessed on October 1, [8] Sea-Distances.Org. Port Distances. Sea Distance / Port Distances - online tool for calculation distances between sea ports. Accessed on October 1, [9] Google Maps. Distances of two locations. Google Maps, Accessed on October 1, ,15z [10] Franklin Associates. Life Cycle Inventory of Packaging Options for Shipment of Retail Mail-Order Soft Goods. A report prepared for Oregon Department of Environmental Quality and U.S. EPA Environmentally Preferable Purchasing Program, USA, Accessed on October 1, 2014.

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