Reduce Your Plastic Waste Footprint
A guest post by Michele Lee
It’s easy to feel conflicted about plastic.
On one hand, helpful plastic materials enable the modern lifestyle that we have all become accustomed to. Plastic packaging allows safe international food distribution and plastic films prevent the spread of bacteria & diseases in highly trafficked settings. Yet on the other hand, plastic waste is destroying our environment. Images of overflowing plastic trash mountains and plastic items choking our marine life continually haunt us all.
While it can feel overwhelming, there are some simple steps that we can take as individuals and small business owners to mitigate the impact of plastic waste. In this article, we describe the different types of common plastics used in packaging and rank each type from best to worst in terms of environmental impact. Maximizing “best” plastic purchases and minimizing the “worst” is an everyday step we can all take towards environmental stewardship.
Not all plastics are created equal
To understand how to deal with plastic waste, let’s first take a look at where plastic comes from. Most plastics are made from a class of materials called polymers. The name polymer comes from Greek origins: “poly” meaning “many” and “mer” meaning “part”. As the name suggests, polymers are created by putting together many repeating parts, and forming what’s known as a polymer chain. Think of these polymer chains as building blocks that can be combined to form the numerous plastic materials that we use every day.
By changing what you use as the single “mer” or monomer, you can give the whole material a different color, flexibility, or strength. These properties are also tweaked by changing how you order and combine the polymer chains. Evaluating sustainability of these materials then comes down to 1) safety of the building blocks that are used (hazard traits) and 2) if the building blocks can be taken apart and reused (recyclability). Some plastic materials fare much better than others.
Different plastic materials can be identified and separated using their unique recycling number, which is often molded or imprinted into the bottom of the container. We have ranked the most sustainable and least sustainable plastics below as a helpful guide when deciding what type of packaging to purchase.
#2 HDPE: Used in milk jugs, juice bottles, shampoo bottles, detergent tubs, some food packaging. #2 plastic ranks the highest because it is guaranteed to be recycled if put in the correct bin. Not only do #2 bottles have CRV value, helping them get picked and sorted out of landfill trash, but they also are very easy to be melted down and remolded into a new product.
#5 PP: Used in ice cream tubs, dip tubs, microwave dishes, and disposable plastic cups. #5 plastic ranks high because over 60% of city recycling facilities nationwide are set up to collect and recycle this plastic, ensuring that it most likely will not go to landfill. Additionally, #5 plastic does not use a high level of toxic “chemicals of high concern” during manufacturing and processing.
#1 PET: Used in water & soft drink bottles, salad domes, takeout clamshells, disposable plastic cups, and peanut butter containers. #1 plastic ranks high because it is the most common plastic to be collected and recycled by facilities nationwide, in addition to having a CRV value. While #1 plastic can easily be reprocessed into new products, it doesn’t rank as high as #2 & #5 because some toxic “chemicals of high concern” are used during material processing and can potentially leak into the environment.
#6 PS: Used in single use cold & hot drink cups, meat trays, take-out containers, and fragile packing material. #6 plastic ranks extremely high on the “bad” list because it is near impossible to reprocess #6 into a new product, resulting in almost guaranteed direct to landfill path. Recycling facilities must use costly manual or optical sorting techniques to remove this difficult material from recycling streams. Additionally, concerns have been raised nationally about the toxicity of chemicals found in #6 plastic, leading to a ban of these plastics in New York City, Washington, DC, and San Francisco, among others.
#3 PVC: Used in cosmetic containers, commercial cling-wrap, and some disposable take-out containers. #3 plastic ranks high on the “bad” list because of its low reprocessing value. Few recycling facilities are able to take #3 plastic, resulting in a landfill path similar to #6 plastic. Additionally, the manufacturing steps used in making #3 plastic contain small doses of potentially hazardous chemicals that can leach into the environment if not carefully controlled.
#7 Other: Used in water cooler bottles, flexible films, multi-material packaging, and take-out containers. #7 plastic is basically a catch-all category for the plastic that does not fit into the other categories. As a result, #7 often contains proprietary mixtures of multiple plastics that cannot be reprocessed or separated for reuse. For the majority of recycling facilities, #7 must be sorted out and sent directly to landfill.
Michele Lee is an MIT-trained materials engineer and PhD polymer chemist working to bring her academic knowledge into the world of industry. During her PhD, she invented and patented wearable sensor technology to prevent skin cancer. She currently advises a number of start-ups on the design & evaluation of new sustainable materials to support the cleantech revolution. Michele also volunteers at the Los Angeles Cleantech Incubator developing growth strategy and market insight for the Waste & Sustainable Materials sector. Connect with Michele via LinkedIn or email at firstname.lastname@example.org.
Additional Resources on Plastics
World Economic Forum, Ellen MacArthur Foundation and McKinsey & Company, The New Plastics Economy — Rethinking the future of plastics (2016, http://www.ellenmacarthurfoundation.org/publications).
Clean Production Action, The Plastics Scorecard: Evaluating the Chemical Footprint of Plastics (2014, https://www.bizngo.org/sustainable-materials/plastics-scorecard-full-report).