Friday, 1 June 2012

Back to it: Recycled or Degradable?

One of the things I'm often forced to consider when researching packaging policies is the question, what is better: recycled plastic or biodegradable plastic? It's the kind of question that can only be tackled with a pro/con list and even then the scales have a tendency to come out looking pretty balanced. In a previous post on the subject, The Fine Plastic Line, I came down on the side (just) of recycled plastic, because it means putting waste plastic back into the system rather than putting it into the ground. And this is why I supported Waterstones' bag policy, the company I work for, who sourced recycled plastic for their bags.

Mystery policy change...
Or, at least, they used to. Because I recently noticed two changes in the bags we're receiving in our store. Firstly, the littlest, greetings card-sized bags are no longer nice, traditional, brown recycled paper. Nope, only plastic ones are available now. And secondly, the texture of the plastic bags are different (large, medium and small alike). More glossy, less dusty. This is because, as further inspection revealed, they are no longer made from recycled plastic. They are now classed as degradable plastic, sourced from a company called EPI Global.

Ok, so for starters, here are two important terms. They sound pretty similar, but actually have quite different consequences.

1. Degradable. This applies to a plastic that is designed to "undergo a significant change in its chemical structure under specific environmental conditions" (source:, leading to the point where it can no longer technically be defined as a 'plastic'. In other words, it simply breaks down to a certain point whereby it no longer resembles it's original form, e.g. is a pile of little pieces instead of a whole plastic bag.

2. Biodegradable. "A degradable plastic in which the degradation results from the action of naturally-occurring micro-organisms such as bacteria, fungi, and algae" (source: as above). In other words, it's broken down by living organisms. In the process of this, the organisms will consume and thus convert the materials' component parts into other things such as living material or gas.

These are two distinct processes and should not be confused. Degradable does not mean the material has gone, it simply means it doesn't look like it did before; it might have a slightly different chemical structure than it did before, but that doesn't necessarily equate to its being harmless. Biodegradable, however, is, in my opinion, much better and more valid - biodegradable is good because it means that the chemicals/materials are available for nature to make use of. Organisms aren't able to use or break down the chemicals in traditional plastics because the molecules are so tightly bound together they can't break them apart - and that's why plastic waste is such a massive problem, there's nowhere for it to go, no way for it to be cycled back into the world's natural systems. So, if anyone is wondering about buying a plastic that is marked as degradable, make sure it is biodegradable, otherwise it's pointless.

EPI Environmental Products Inc.EPI Global and TDPA
So what do EPI Global do? Well, they market a chemical called TDPA. TDPA stands for 'Totally Degrdadable Plastics Additives'. It's a chemical that plastics manufacturers can add to their product - e.g. a plastic bag - that, after a certain period of time, will catalyse that product's degradation. That means its presence will considerably increase the speed at which the bag will break down into smaller pieces. TDPA causes (a) the long polymer molecules that constitute plastic to be broken down into shorter molecules, and (b) promotes oxidation. The oxidation (i.e. oxygen groups attach themselves to the polymers) causes the molecules to became hydrophilic (i.e. attractive to water) and small enough to be eaten by micro-organisms, thus available for biodegradation.

Now, I've always been a bit suspicious of claims about biodegradable plastic. I can't help but wonder whether the science works in reality, whether it holds up its end of the bargain once the plastic is in the real world, being subjected to real and changeable environments. Sure it may work in the lab where everything is controlled and the perfect conditions are provided, but I know the real world rarely functions in quite the same way as a laboratory. This is one reason why I generally go for recycled over biodegradable. Another reason is that I don't think its sensible to be making plastic items out of virgin plastic (i.e. brand new plastic resin), given as (a) we're up to our knees in it already, and (b) making plastic is a dirty business that uses valuable resources.

And back to Waterstones
The truth is, I'm not sure how I feel about Waterstones' policy change when it comes to plastic bags. I guess I'm disappointed, mostly because I haven't seen anything about the decision on either their internal or external CSR (corporate social responsibility) pages - in fact, on their policy continues to incorrectly state that the company uses recycled plastic for their bags. The company was bought out nearly a year ago by a Russian oligarch, and a new MD, James Daunt, installed. He's been making lots and lots of interesting and exciting changes to the business, but I'm disappointed that CSR seems to have slipped off the radar a little bit. If I was given the opportunity, I'd love to get more involved in this at a head office level, because at the moment there doesn't seem to be much opportunity for the average bookseller to get their voice heard about environmental concerns at the higher level. When I tried, a couple of years ago, to question their wrapping paper choices, I never got a response. I absolutely understand that Mr Daunt has a lot of much more pressing business concerns, but that doesn't make CSR any less important.

So, I'd like to know:
1. Waterstones, why have you changed your bag policy? What information made you decide to discontinue the small paper bags, and switch all plastic bags away from recycled to degradable?

2. EPI Global, can I see your plastic biodegradation for myself?

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