Which Shrink Film Is Most Environmentally Friendly? Bio-Sourced, Compostable or Biodegradable?
When you are sourcing the right packaging for your products, there’s a lot to consider. Price, aesthetics and durability are important, as well as whether it’s hygienic enough or offers adequate protection. However, one major and growing concern is the impact of our packaging on the environment, particularly when it comes to choosing a plastic flexible like shrink film. We all want to do what’s best for the planet, but there’s so much confusing and sometimes contradictory information around the topic, how do you know you’re choosing the right material?
WRAP (Waste and Resources Action Programme) UK is a body that is working alongside our government to bring about a sustainable, resource-efficient economy, focusing on waste reduction and a REDUCE, REUSE, RECYCLE model. WRAP advocate a Full Circle Economy as the most sustainable and environmentally friendly way forward – a system where the stage of ‘waste’ is eliminated and replaced by ‘recycling’, leading back into the ‘resources’ stage where materials are made back into their original form for reuse.
Using the Full Circle Economy model, we have evaluated three types of plastic flexibles to see how they stack up:
This is defined as a material that is derived from a renewable resource and composed from polymers derived, in whole or in significant part, of biological sources e.g. starch, sugarcane, cellulose, oils, lignin etc.
Our PE B-NAT shrink film, manufactured by Bollore and ©Braskem, is a perfect example of a bio-sourced plastic flexible. It is formed from a base of 46% sugarcane ethylene in a process where the sugarcane is ‘squeezed’ five times. The first two squeezes produce pure sugar for the food supply chain. The last three squeezes produce an ethanol bi-product which is unfit for human consumption and is processed into the base for our B-NAT shrink film, rather than being wasted. Harvested in Brazil, the operation barely impacts on any arable land at all, utilising only 0.02% of land for sugarcane production, and is located over 1200 miles away from any rainforest.
Once B-NAT shrink film reaches the end of its useful life, it can be recycled in the UK (SPI code 04) using existing recycling streams back into the full circle economy.
A major benefit of switching to a bio-sourced plastic, besides the green credentials, is that they possess properties which are identical to conventional plastics derived from fossil fuels; yet they help to reduce a product’s carbon footprint. Work is underway right now to keep increasing the percentage of bio-sourced material in our film.
This is understood as ‘a product that can be broken down by microorganisms (bacteria or fungi) into water, naturally occurring gases like carbon dioxide (CO2) and methane (CH4) and biomass.’ Biodegradables should be able to decay naturally, breaking down within a defined period of time. Biodegradables are commonly perceived by the public to be the ‘greenest’ form of packaging. However, the reality is not quite so clear cut and WRAP’s official documentation advises a cautious approach, stating: ‘The fact that a plastic is described as biodegradable does not mean that it should be freely released into the environment in an uncontrolled manner. The speed, method and nature of biodegradation differs between materials and users should question the behaviour of biodegradable materials before using them in any application.’
Physics tells us that ‘nothing is lost, nothing is created, everything is transformed’. Unfortunately, plastic cannot simply disappear. The biodegrading process involves microorganisms breaking down the material, merely transforming it into plastic micro particles which are toxic for our planet. Tiny plastic fragments make their way into oceans, are eaten by plankton and in turn are eaten by fish. By the time fish reach our food chain, this problem of our own making is very much back to haunt us.
Furthermore, because biodegradable plastics are made to break down after consumption, they cannot be recycled, breaking the full circle economy loop. Resources perpetually have to be pumped into the manufacturing stage to ensure a continued supply of the material, using fuel and energy and emitting CO2 and other harmful emissions.
Again a popular choice for the environmentally conscious, compostable packaging materials are designed to decompose in industrial or home composting systems, leaving no toxicity in soil. Sounds great! However, very specific conditions have to be met before the plastic will decompose in an industrial system including elevated temperatures of 55-60°C, high relative humidity and oxygen presence. As such, compostable plastics that end up in a landfill or simply discarded at the side of a roadside will not break down, despite the common misconception that it will compost in any environment. Although home composting requires less demanding conditions, there is no current regulated standard for testing and certifying these materials and very little regulation over their disposal.
This requirement for precise conditions in the composting process creates further challenges. WRAP UK have advised that processing compostable waste should not be collected with dry recycling because it can disrupt and compromise current recycling streams. RecycleNow concur, stating that ‘Compostable and biodegradable bags are not designed to be recycled and if they enter the recycling system can potentially cause quality issues in the recycled material.’ In order to accept these materials, recycling sites must have a separate composting step for the treatment of digestate fibre, else it will be removed during pre-treatment and sent to landfill. Currently only 52 (3%) of recycling plants in the UK have the appropriate streams needed for compostables, suggesting the infrastructure is not currently in place for its widespread uptake.
Like biodegradable plastics, compostable alternatives also do not meet the full circle economy requirements championed by WRAP. As they are intended to decompose at the end of their useful life, they cannot be recycled back into the circular loop, therefore compostables continue to use more and more energy and resources in the production stage.
…and so the most eco-friendly is?
Not every packaging application is suitable for all types of plastic flexible use, although bio-sourced films are very flexible. Furthermore, many alternatives to fossil-based plastics have positives and negatives, making it very hard to decipher which is the best solution. Inconsistencies in recycling facilities and recycling messages across the country cloud the answers even further.
However, considering all factors, at YPS we believe that the most sustainable film types are recyclable bio-sourced plastic flexibles. The recycling facilities are in place already and they fit into the full circle economy vision. Our bio-sourced solution, B-NAT, is kinder to the planet in the production stage and we are constantly looking to improve it’s credentials. The rest of our range of shrink films are fully recyclable with OPRL approval and we are supplying ultra-thin films where possible to reduce overall volumes of plastic in our packaging.
For more information about environmentally friendly packaging solutions, call 01924 441355 to speak to our shrink film experts.