A Few Perspectives on Compostable and Degradable Plastics

1. A Few Perspectives on Compostable and Degradable Plastics David Allaway Oregon Department of Environmental Quality (503) 229-5479 allaway.david@deq.state.or.us

2. Degradable “Bioplastics” Plastics PE from biological sources (e.g. Braskem) Oxo- degradables PLA

3. Sustainable Packaging Coalition’s “Definition of Sustainable Packaging” • Beneficial, safe & healthy for individuals and communities • Meets market criteria for performance and cost • Sourced, manufactured, transported, recycled using renewable energy • Maximizes use of renewable or recycled source materials

4. Sustainable Packaging Coalition’s “Definition of Sustainable Packaging” (continued) • Manufactured using clean production technologies and best practices • Made from materials healthy in all probable end of life scenarios • Physically designed to optimize materials and energy • Effectively recovered and utilized in biological and/or industrial “cradle-to-cradle” cycles

5. The Landfill “Problem” “More than 60 million plastic, petroleum-based water bottles end up in landfills every day, that’s almost 40 billion annually. Once there, they will last for centuries . . .”

6. DEQ’s Life Cycle Analysis of Drinking Water Delivery Options • Widespread belief: recycling prevents/avoids/negates the environmental impacts of consumption • Somewhat true, but how much? • Existing studies aren’t specific to North America, lack transparency, and/or aren’t comprehensive • Oregon’s bottle bill expansion • Lots of interesting packaging questions Regardless, DEQ’s study is less about water, and more about comparing disposal, recycling, and prevention

7. DEQ’s LCA of Water Delivery • 3 basic systems: • Lead contractor: Franklin Associates

8. Subscenarios • “Water bottles” (single-use) • 25 subscenarios • 21 from local sources (<150 miles to retail) • 4 PLA, 17 PET • 4 “imports” (Maine, France, South Pacific) • 3 PET, 1 glass • “Home office delivery” (“HOD”) • 11 subscenarios • Tap water • 12 subscenarios • Subscenarios include “best” and “worst” cases for each system

9. Variables: single-use water bottles • Bottle material (PET, PLA, glass) • Bottle weight (mass) • Bottle volume • Recycled content (PET only) • Bottle molding energy • Cap weight • Corrugated packaging weight • Film packaging weight • Water source type and treatment technologies

10. Variables: single-use water bottles (continued) • Distance: bottle molding to filling • Distance: filling to retail • Ocean transport: weight-based or discounted allocation • Distance: retail to home • Trip fuel use allocation • Chilling (at home) • Recycling rate • Recycling allocation method • PLA composting • PLA landfill decomposition

11. Disclaimer! • DEQ’s study is still in process • External critical review is not yet complete • Study is not yet ISO compliant • Use/cite results at your own risk! • DEQ requests that you not cite this study until it has been finalized and published

12. Contribution Analysis (GHGs): Single-Use Bottles (Draft Results) net: 1,121 926 1,080 1,171 Lbs CO2e per 1,000 gallons “Baseline” = PET, half-liter, 13.3 g, 0% recycled content, purified municipal water, 50 miles to retail, on-site molding, 5 miles home-to-retail, co-purchase w/19 other products, no chilling, 62% recycling

13. Contribution Analysis (GHGs): Single-Use Bottles (Draft Results) net: 1,121 775 1,135 w/o wind credits: 1,121 1,106 1,465 Lbs CO2e per 1,000 gallons PET “baseline” 62% recycling PLA, 62% compost, 100% decay in landfill PLA, 62% compost, 0% decay in landfill Assumes no cross-contamination between PET and PLA; no land use impacts

14. NatureWorks/OWS Testing of Ingeo Pellets at 21 oC. Source: NatureWorks LLC

15. NatureWorks/OWS Testing of Ingeo Pellets at 35 oC. Source: NatureWorks LLC

16. What else do we know about PLA and landfills? • Internal landfill temperatures can exceed 50 oC. • Gas generation continues for decades (wet) or centuries (dry) • PLA degradation is temperature and moisture dependent. • Below 50 – 55 oC., degradation is very slow. • Above 50 – 55 oC., with moisture, degradation is very fast. • PLA has a two-step degradation pathway: • Polymer chains are broken down via hydrolysis to smaller molecules • Micro-organisms consume the smaller molecules as food.

17. Comparison of PET and PLA(with wind energy credits) (draft results) PET = 100 Assumes no cross-contamination between PET and PLA; no land use impacts

18. Comparison of PET and PLA(w/o wind energy credits) (draft results) PET = 100 Assumes no cross-contamination between PET and PLA; no land use impacts

19. LCA Conclusions (Draft) • At 62% diversion and 38% disposal (94% landfill, 6% combustion): • PLA and PET are comparable in many impact categories • PET has lower eutrophication potential • PLA has lower ecotoxicity and smog potential • PLA has lower acidification potential only if wind energy credits are included • PET has lower respiratory effects potential only if wind energy credits are not included • Global warming potential depends on wind energy credits and the fate of carbon in landfills

20. Concluding Thoughts • DEQ’s LCA assumes no cross-contamination of PET and PLA recovery. • There are excellent reasons to protect PET recycling • However, protecting existing recycling should not create insurmountable barriers to innovation in materials • DEQ’s LCA is limited to water bottles. • No consideration given to co-benefits (PLA) of food waste composting. • DEQ has not evaluated recycling of PLA.

21. More Concluding Thoughts • Majority of impacts are upstream • PLA is a relatively immature technology and NatureWorks will likely continue to reduce environmental impacts . . . • . . . however, so will PET producers . . . • . . . and there are other bioplastics in development. • Need better understanding of fate of PLA in landfills. • Public perception to the contrary, degradability in landfills is not necessarily desirable.