There are many reasons why, over the last 60 years, plastic
has increasingly replaced other materials such as glass and metal. Plastics are
cheap and easily processed, allowing large amounts of design freedom including
shape and colour. They are low in weight, but high in strength, making lifting
and transporting easy while providing a hygienic and safe method of packaging.
However, despite the many positive attributes of plastic, it
does have negatives. Two important issues are the greenhouse gas emissions
resulting from its production and incineration after use, together with the
degradation of the natural environment due to plastic pollution.
How to address these challenges is an area of intense debate,
which, despite the stakeholder consensus on the need for action, results in
conflicting opinions on the best solutions. At the epicentre of the plastic
debate are the so-called single-use plastics and the use of plastics as a
packaging material.
So, what are the options for packaging? Revert to older
materials such as glass or metal? Consider new materials produced from
renewable plant-derived raw materials? Adopt compostable materials? Increase recycled
content? The options are manifold, and each one provides different benefits
while introducing new challenges.
At NNFCC, we have worked with many companies, including
packaging manufacturers and brand owners, to define and assess these options and
produce rational fact-based conclusions.
In a recent project, NNFCC worked with UK based clear
packaging producer Stäger to assess a range of material options available as sustainable
replacements to their current material of choice: PET plastic.
Stäger’s packaging can be seen on retail shelves showcasing food,
confectionery, cosmetics, and toiletries. With quality products requiring
quality packaging, the technical performance of the material is paramount. In Stäger’s
case, this means a transparent material capable of being folded with a high-quality
finish.
An initial screening exercise identified several candidates
worthy of further investigation, which included polylactic acid, cellulose
acetate, ‘biobased PET’ and the new PET alternative: PEF.
Each material option was considered in relation to its
performance characteristics, availability, cost, environmental impacts and fit
with near-term waste infrastructure and legislation.
For many consumers the link between plastic, crude oil, and
the climate creates a strongly negative perception about plastic products. The
shift to renewable plant-derived raw materials can break this perception link
and lead to real sustainability benefits. Each of the identified materials are
fully or partially produced from renewable raw materials and therefore fulfil
the desire to move away from crude oil.
It would however be incorrect to link the use of renewable
raw materials during the production of a product to any of its end-of-life or
waste disposal opportunities. In this respect, a plastic product produced from
renewable raw materials, correctly called a biobased product, could be as
durable as any petroleum plastic or as biodegradable as paper.
It is important that packaging materials are designed with
consideration for their eventual disposal. From an environmental perspective, the effective
recycling of a plastic product generally represents the preferred disposal
route. However, despite the fact that nearly all types of plastics can be
recycled, the majority are not. This is due to the complexity of waste
collection, the sorting of mixed plastics, issues with contamination preventing
recycling, and the resulting (often unfavourable) economics of recycled plastic
versus virgin plastic production.
Within some stakeholder groups there is a belief that
recycling issues point to the need to move towards biodegradable materials.
Although superficially attractive, biodegradable materials still require
defined disposal routes, since being biodegradable cannot be seen as a license
to allow waste products into the environment. It is also not a panacea for the
problem of plastic marine litter.
In respect to biodegradable packaging, this means that
packaging must be designed for, and capable of entering, food or garden waste
collections destined for composting facilities. The use of the compostable
packaging standard, EN13432, ensures the suitability of packaging for
composting although a range of other factors including facility acceptance also
influence the effectiveness of this route.
Stäger currently produces packaging incorporating 60%
recycled and 40% virgin-grade PET. Recycled PET has a considerably lower
environmental impact relative to virgin-fossil PET. The environmental benefits
of using recycled PET coupled with the high recycling rates for PET underpin
Stäger’s current sustainability strategy.
A shift from virgin fossil to virgin biobased PET would
enhance Stäger’s sustainability credentials. Considering a range of
environmental impacts, the move to biobased PET (with commercially available 30%
renewable content) would reduce the environmental impacts by over 10%. Furthermore,
the commercial development of PET with 100% biobased content is being actively
pursued by several leading brands including Coca Cola and PepsiCo, offering the
potential for greater environmental gains.
As a responsible packaging producer already producing
products with high recycled content, Stäger were keen to understand the options
to introduce compostable materials into their product offering. Although a
switch to cellulose acetate in Stäger’s applications does present some
technical challenges, it also presents the opportunity to switch to a
compostable product. Cellulose acetate is certified for both home composting (when
<0.106mm in thickness) and industrial composting.
Compostable products provide an alternative waste disposal
option ideal for products which are hard to recycle, such as mixed or food
contaminated products. If, however, recycling is considered feasible and
realistic, then the advantages of composting should be carefully weighed against
the benefits of recycling. Other important considerations include whether the
use of compostable packaging enables the effective management of other waste
i.e. diverting food waste from incineration or landfill; or what the likelihood
is of consumers placing the material in the correct disposal system.
Overall any material choice will come with positives and
negatives which need to be carefully balanced.
The environmental impacts of plastics can be reduced in both
production and disposal. During production, the use of recycled and/or
renewable raw materials should be assessed, and the product’s end-of-life
should be considered, ensuring that the product is easily recyclable or
compostable. Adopting a life cycle thinking approach to material choice and product
design ensures that sustainability is considered from the outset.
Ultimately the best way to reduced plastic pollution is to stop
polluting with plastic. Consumers, producers and governments should all take
responsibility and ensure that all plastic waste not only makes its way into
the appropriate waste facilities but also that the appropriate waste facilities
are in place.