Is there a future for plastics?
August 30, 2018 by Jannick Schmidt
Plastic is a ubiquitous material with many benefits such as low price and weight and an extreme functional versatility. Plastics are pervasively used in modern society.
However, the uses of petro-based plastics present us with some serious problems. First of all, we are talking about huge amounts of plastics. The approximate global production is around 480 mio tonnes of plastics produced every year (2011 data) and is expected to double within the next 20 years. Currently the production of plastics accounts for around 3% of global GHG emissions.
Research from the past decade has demonstrated plastic contamination from micro-plastics being washed out as products are produced and used. Microplastics are now routinely found in marine food chains, and the situation in terrestrial and freshwater ecosystems might be the same, as recent research demonstrates. Furthermore most of us have seen troubling pictures of ‘macroplastics’ contaminating oceans, landscapes or cities around the world. Plastics in the environment cause serious ecological problems, but also represent a substantial economic challenge, as materials are wasted and fisheries and tourism are negatively affected.
In January 2018 a strategy to turn the ‘plastics economy’ into a circular economy was put forward by the European Commission as one of the solutions to the environmental problems of the production and use of plastics. In a circular economy, focus is on keeping the values in the economy for as long as possible by keeping them in the ‘loop’ by reuse and recycle initiatives, as well as to minimise the materials (waste) that goes out of the loop.
For plastics, special attention is on reducing the waste component, as around 95% of plastics are only used once. Improving designs and options for consumer sorting and recycling can be an important part of the solution. Similarly there is a potential to improve the economy of post-use plastics as the market lacks unified standards and infrastructure for reprocessing. A final approach that is often mentioned is to innovate various non-petro plastic systems, leading to products that are bio-degradable.
While the circular economy thinking intuitively makes sense to consumers and decisions makers, there are quite a few pitfalls seen from the life cycle assessment (LCA) perspective. When real life causalities are not appropriately investigated and considered, I am left with such questions as: Is recycling always a good idea? How do we compare single use vs. multiple use solutions? Are the alternatives to plastic really better for the environment?
Unfortunately, these questions are often not addressed. In the supermarkets, I begin to see bio products being labelled with blatantly incorrect claims, such as being 100% CO2 neutral. Let us remind ourselves that the old adage ‘there is no such thing as a free lunch’ is true here as well – producing and using bio plastics has environmental implications just as the petro plastics have.
Luckily, we have the tools to arrive at a more balanced view of the pros and cons by applying LCA that provide answers to the above question (and more). Some of my rules of thumbs are:
- Always consider the trade offs (What is being replaced? Pick the solution that is actually best for the environment, avoiding suboptimisation)
- For recycling, consider what is replaced (i.e., can reuse replace equal materials or products – avoiding down-cycling?).
- Biomaterials or products are not inherently free of GHG implications, land use effects, or biodiversity concerns (look at the full picture).
- Be critical – find the relation between causes and effects (e.g., marine litter is not caused by plastic production, but a missing waste management)
- Realize that sometimes more investigations are needed to reveal the true consequences of product choices.
As sustainability professionals, we need to support the decision makers and consumers to ask for truly sustainable designs and material choices. Sometimes this implies saying something that goes a bit against the grain.
It is important to distinguish between micro-plastic and “macro-plastic”. Micro-plastics, e.g., micro-beads used as scrubbers and micro-fibres from washing of synthetic textiles, pass unaltered through most waste treatment systems, and end up in the environment. Micro-beads have no options for recycling, and biodegradable alternatives are available. Thus, there are obvious reasons for banning such products, as has already been done for their use in cosmetics and personal care products in a number of countries.
For synthetic textiles and macro-plastics, the picture is quite different. When considering the alternatives, petro-plastic based products often turn out to be better for the environment, as long as it is collected and properly treated after use, so that it does not end up to decompose in nature. Capturing micro-fibres directly from the washing process therefore appears a necessity. When suggesting designs for recycling we need to make sure that fractions are clean or can be easily separated, so that downcycling is avoided as far as possible. In some situations switching to selling ‘a service’ though rental, instead of selling ‘a product’ can be a game changer, as rental comes with built-in repeated use of the product. Take-back systems also need to be investigated further, and those that actually work for the environment should be chosen over those that miss the point.
I believe there is a sustainable future for plastics, when we seriously consider the facts that we have at hand.
 Law K L 2017. Plastics in the Marine Environment. Annu. Rev. Mar. Sci. 9:205–29. https://www.annualreviews.org/doi/pdf/10.1146/annurev-marine-010816-060409
 Cole M, Lindeque P, Halsband C, Galloway T S 2011. Microplastics as contaminants in the marine environment: A review. Marine Pollution Bulletin 62(12): 588-2597 https://www.sciencedirect.com/science/article/pii/S0025326X11005133
 Rochman C M 2018. Microplastics research—from sink to source. Science April:28-29. https://www.science.org/doi/full/10.1126/science.aar7734
 Communication from the Commission to the European Parliament, the Concil the European Economic and Social Committee and the Committee of the Regions. A European Strategy for Plastics in a Circular Economy.