Gut feeling says plastics are bad for the environment – but are the alternatives really better?
We all know the images of plastic in the oceans, animals trapped in plastic or with plastic in their stomachs, and the concerns about microplastics accumulating in living beings
Policy has started to address plastic through legislation and regulation but is the gut feeling confirmed by life cycle assessments?
Reality is of course more complex and life cycle assessments show replacing plastics often leads to significantly higher CO2 emissions. For metals and glass, considerably more energy is required in production and in subsequent transport
Plastics can frequently score points against natural materials. A comparison of a polyethylene shopping bag, which is now banned in Europe, with a cotton shopping bag came to a clear conclusion: the cotton shopping bag would have to be used 100s of times before it could equal the environmental balance of a polyethylene shopping bag used once. Plus, the cotton bag is never to be washed or the impacts of the washing process must be added on top
The reasons are the agrochemicals used in cultivation and the complex production process for the yarn, fabric and bag
In France, plastic film is now to be banned from protecting vegetables but this has the danger of higher CO2 emissions due to increased food losses and a reduction in the quality of the vegetables
Fruit and veg are living plants, constantly interacting in complex ways. In supermarkets, they are still photosynthesising, making new compounds, breaking down others and even emitting growth regulators that affect the behaviour of neighbouring crops on the shelves around them
Understanding these incredibly sophisticated interactions and how to control them has led to ingenious inventions including wrapping, that have dramatically extended the shelf life of crops. Waste has been slashed and nutritional quality and flavour improved.
A recent study looked at cucumber production and found that plastic packaging was responsible for only 1 per cent of the total environmental impact of this food, yet each cucumber thrown away because it spoiled has the net environmental impact of 93 plastic wraps
Of course, this is not to say that plastic films are useful in every case – but when they are beneficial for quality and CO2 footprint, they should stay! If we want to achieve a sustainable future, we need differentiated science-based guidelines and political regulations, not decisions that primarily satisfy the gut feeling of consumers and politicians!
If the plastics are produced from renewable carbon – bio-based, CO2-based or recycled – instead of the mainly used fossil carbon, their balance looks even better because the carbon is kept in a circular economy
If we’re going to use plastics, let’s use the right ones!
Do you agree we should be more specific about sustainable solutions?