The one fundamental fact that links all discussions about trying to do the best for planet Earth is things are rarely as simple as we would wish. This warning applies not only to discussions but also, more seriously, to actions as well.
An initiative that is being rolled-out in the UK and many other countries is to reduce the amount of plastic used for throw-away products such as carrier bags and drinking straws. The initial plan was to use fully recycled (and recyclable) materials but plastics are now being shunned completely in favour of different materials that are often plant-based.
For example, I was recently given a carrier bag that looked and felt like plastic but it was actually made from sugarcane. Interestingly, I was told that it might start to feel sticky if it got wet. Eager to find out more, when back at home I poured water on the bag and found there was no such effect, even after 24 hours. I then restarted the experiment with a wetted paper bag alongside: predicatbly, the water immediately started soaking into the paper bag. It is safe to say that whereas paper bags wouldn’t be good for carrying items in the rain, sugarcane bags seem to be perfectly viable.
All of which leads neatly to the issue of straws, which have long been made of plastic but are now available in more eco-friendly forms that offer two different approaches; biodegradable throw-away items (made of paper, for example) and reuseable items (such as those made from stainless steel).
According to research conducted at the University of Antwerp, published in the August 2023 issue of Food Additives & Contaminants: Part A (see below for details) many of these eco-friendly straws contain synthetic chemicals known as PFAS, which are both very durable and also potentially toxic. Of the 39 different brands of straws tested, all commercially available on the Belgian market and covering five different materials (paper, bamboo, glass, stainless steel and plastic) only the stainless steel straws had zero contamination.
What does this mean? Firstly, the (very low) levels of PFAS measured could be due either to deliberate additives, perhaps to provide water-proofing, or to unwanted contaminants that happen to exist in the environment. The latter explanation might appear more likely as the PFAS levels were highest in the plant-based straws (paper and bamboo) and could have been absorbed during growth. On the other hand, you might argue that paper and bamboo are precisely the materials that are most likely to need deliberate water-proofing.
Whatever the origin of the PFAS present, the second point of significance is that switching to plant-based materials does not ensure the absence of synthetic chemicals, leading the researchers to conclude: “The presence of PFAS in plant-based straws shows that they are not necessarily biodegradable and that the use of such straws potentially contributes to human and environmental exposure of PFAS”.
Plastic straws may well be bad for the environment but eco-friendly straws may only turn out to be “less bad” rather than “good”. Stainless steel straws might be the best option but are likely to require a higher energy input for recycling and manufacture. So perhaps the best answer is simply to use fewer straws, reserving them exclusively for young children and medical situations? Or would these be the worst places to use them if they contain even very low traces of potentially toxic chemicals?
As I observed at the outset, when it comes to trying to do the best for planet Earth, things are rarely as simple as we would wish.
For more details about the University of Antwerp research…
- a summary is available here (https://phys.org/news/2023-08-paper-straws-environment-plastic-versions.html)
- the full paper is available here (https://www.tandfonline.com/doi/full/10.1080/19440049.2023.2240908)
Mr Tarrant's physbang 'blog 