It’s time to get pragmatic about plastics in packaging

Authors: Caroline Potter, VP of Sustainability and Elizabeth Clark, Sustainability Consultant

Single-mindedly backing one packaging material (e.g. paper) over another (e.g. plastic) in the name of environmental sustainability misses the point. In fact, it only serves to distract from the seriousness and complexity of the issues that industry must tackle. Read on to find out why a more balanced perspective is needed.  

Consumer goods companies are frequently challenged on their use of plastic packaging. Many have made pledges on sustainable packaging which include targets for overall plastic reduction.

Plastic is a controversial material, but it’s also versatile and effective, facilitating cheap, functional, and highly convenient packaging solutions. Low weight and high strength mean it’s transportable, stackable, and resilient to damage, while its durability and low permeability can support longer freshness of perishable goods, helping to reduce waste. Carbon footprint assessments of plastic packaging are frequently better than those for packaging made from alternative materials too. This is partly due to its lightweight and the fact that less material may be needed to satisfy the same functionality requirements.

When sustainability is considered holistically, plastic can sometimes be a better packaging choice if the right type is selected. However, plastic pollution remains a problem and steps are being taken to reduce how much is used, including the United Nations Environment Programme negotiations for a global plastic treaty.

Alternative packaging materials need careful consideration

From a consumer goods perspective, various strategies have been employed to reduce plastic packaging. Decreasing the amount used per pack is one measure and switching to paper or compostable plastic materials is another. However, this is a complex area. The pros and cons of different approaches require careful consideration, as the following three examples show:

1) From rigid to flexible plastics

Switching from rigid to flexible plastic enables a reduction in the amount used per pack. However, it replaces a material that may be readily recycled (depending on the location) with one that is much harder to recycle. Use of flexible plastic for food products can also be viewed negatively by consumers as it can make the contents look less appealing. This was the case recently when UK supermarket Sainsbury’s swapped its rigid minced beef packaging for a flexible plastic. Some consumers were critical of the change, complaining about the more compact shape of the vacuum-packed product, noting that it also led to reduced functionality.

2) From plastic to paper

Various surveys have shown that consumers prefer paper/cardboard packaging and plant-based, compostable packaging to plastic due to their perceived sustainability. However, the true picture for environmental sustainability is often more nuanced.

For paper to function as an effective packaging material it often needs a coating, which is generally made of plastic. This can affect its recyclability. Uncoated, non-contaminated paper can be readily re-pulped and reused, but this is not the case for papers coated in a laminate or a wax. Organisations such as the Waste and Resources Action Programme (WRAP), Confederation of European Paper Industry (CEPI), and American Forest and Paper Association (AFPA) offer guidance on the amount of plastic that can be managed without hindering the recycling process. This is often presented as the percentage contained in an individual package, but the proportion in the whole system also has an impact.

Variations between recycling infrastructures in different countries present further challenges. In markets without separate collection for different types of packaging material, small wrappers are likely to slip through sorting machines (this is not an issue for markets where paper is collected separately to glass, aluminium, and plastic).

In addition, a widespread surge in the use of paper could contribute to deforestation. More scrutiny is being placed on deforestation in supply chains, as the recent  EU Regulation on deforestation-free supply chains indicates.

We elaborate on this matter and other material options, such as aluminium, in our whitepaper, Reducing plastic waste: why choosing the right material isn’t as simple as you think.

A plastic bag drifts in the clear blue ocean as a result of human pollution. Perfect for ocean conservation theme. (This bag was collected and taken out of the ocean)

3) From plastic to compostable materials

Compostable plastic materials are being developed and access to separate organic waste collection is increasing, but challenges remain. For example, some materials advertised as compostable don’t really degrade fast enough – particularly in home composting conditions. A citizen science initiative in the UK, The Big Compost Experiment, found that 60% of biodegradable and compostable plastics certified as ‘home compostable’ did not fully disintegrate.

Polylactic Acid (PLA) is one of the most well-known industrially compostable plastic materials. However, it requires very specific temperature, moisture, and microbial conditions to biodegrade. Some industrial composters are unconvinced that the material is suitable for their facilities. What’s more, organic waste collection does not usually permit the inclusion of compostable packaging.

Plant based and bio-based plastics are another option. But their production requires bioresources, and depending on the source this could contribute to loss of biodiversity and land, as well as water pollution.

These factors are further considered in our packaging innovation whitepaper, How to take a strategic approach to the evolution of packaging. It highlights three critical checkpoints to bring shape and structure to the innovation journey: Defining the purpose, Considering your material and design choices, and Reimagining the end of life.

The plastic recycling paradigm

When it comes to the recycling of plastic packaging, consumers’ willingness to participate and dispose of the material properly is a critical factor. There is a widespread need for better collection and sorting of plastics for more effective recycling, but this is not the whole answer either. Constraints include the degradation of materials after mechanical recycling, resulting in loss of desirable properties such as strength and transparency. Chemical recycling is a possible alternative. This can be defined in different ways but when it reduces plastic to its base components it can enable the creation of new materials. Further development is required before this approach can be applied at scale however, and it also uses considerable energy. It may form part of the solution, but it’s currently positioned below mechanical recycling in the waste hierarchy.

With no panacea, pragmatism is key

Finding ways to limit the amount of plastic entering the environment is vital, but there is no universal solution. Sustainability credentials of alternative packaging materials must be evaluated and interrogated on a case-by-case basis. Otherwise, despite the effort and investment, businesses may simply end up switching one damaging solution for another.

Find out more about our sustainability consulting services drawing on the skills and expertise of scientists, engineers, and regulatory specialists. 


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