“I’m really unsure about your move to compostable plastic”.

“I’m really unsure about your move to compostable plastics”. That was the opener for Alastair to slide into our Dms.

But unlike most unsolicited messages, with over 25 years in the waste and recycling industry Alastair actually knew what he was talking about. Head of climate positivity and CEO Rob immediately hit him up for a chat. The result? A rethink of on our packaging and how we wash out that used yogurt pot…

"I spent the day out on the on the trucks yesterday.

I try and do it slightly less than quarterly. Just go out with the [recycling truck] drivers and go and spend time with them to understand what’s going on at the coal face. I’ll also do a day on the picking line three or four times a year.

It’s really important to see what's coming through in the recycling. So when I’m talking to customers about the reality of recycling. It's like, you know, when someone asks “why should I wash my recycling?” I can say, well, there’s a human actually picking through it. So there's a bit of kindness to this for a start. Secondly, if you were picking it, would you pick the nice clean one or the one that's covered in five-day old yogurt?

It kind of makes people think right okay, so there's a reality to all this. Once you throw it magic doesn't happen. It's a lot more than that."

Presca packaging.

"Currently you use a compostable mailer but the problem with compostable plastic is the net nutrient deficit that you create. From taking plants to refining the material to create a polymer, then to put that back in the soil at a net nutrient loss and the high amount of carbon output for doing that, doesn't really sit very well.

We know that nutrients are running out in the world, and we're overshooting the amount of nutrients we've got so then that's the base point.

The second issue is the availability of composting and how quickly compostable materials break down. The ideal reason to have a compostable material or biodegradable is if it's likely to be littered. So, if there is a high likelihood that your packaging is going to be littered then okay, it breaks down in the environment over the amount of time. But that’s not happening here.

The best chance of a compostable plastic to break down is in an In Vestibule Composting (IVC) system which is with added heat – it’s an unnatural environment and it will break down pretty quickly, on the timespan of days to a couple of weeks - it's a quick process.

But compostable plastics that go through that still don't break down well unless they've been shredded. So you need to add another energy source of running a machine to shred the stuff before it goes in and there's not a wide network of IVC facilities around the UK.

The other type of composting is windrow composting, which is literally lines of vegetable matter outside, this creates its own heat and then it breaks down as a normal compost heap might do. Compostable plastics just won't break down in the timescale of this so it doesn't work in that environment.

Then looking at home composting, I just wouldn't feel comfortable with putting plastic into my composter with it going directly into the soil and added to that it will take a long time to break down if the conditions aren’t right.

Finally if the compostable plastic was to go into the film recycling at the supermarket it would downgrade that recycling stream and that would absolutely add risk into everyone else's recycling. This is same with the water soluble plastics as well– they will downgrade other recyclable material. Looking at other options I think glassine is probably the least effective. There’s a lot of energy that goes into producing this type of paper (whether from recycled or virgin sources). To get a more tear resistant, semi waterproof very fine paper like glassine you add an extra amount of pressing, heating and energy use.

There’s a lot of energy upfront, and also a bit more difficult to recycle. If it doesn’t break down in the recycling chamber within a set amount of time it will just be taken off as a waste stream. That’s the problem with coffee cups they take three times longer to break down than normal paper and card.

Then you're onto the bio based plastic which potentially can be good.
The main question is the resources that go into it. There's a place in Brazil who make a polymer that is a byproduct of sugar cane by-products. As long as this is genuine byproducts then there is a good net carbon reduction. So actually not a bad option."

Back to bags?

"For me the best idea is probably to go for a traditional polybag with as high recycled content as possible. You can get up to 100% recycled poly which is widely recyclable and doesn't downgrade any waste streams it goes into.

With all of these things, the idea is to go to as narrow a band of materials that are going into production as possible. This way you've either got poly propylene, or LDPE that you can be pretty sure is going to get recycled. The wider the range of materials that go through a recycling line the harder it is to pick out the recyclables. But if you narrow what the production is, then you're going the right way about it. That’s why I’d recommend a very recyclable bag like a poly-bag made from the highest recycled content you can use.

There are plenty of supermarkets that will take film plastic bags for recycling now, and these are all listed on the Recycle Now website. You put in your postcode and they will tell you all of the places that will take plastic film.

The best thing that you can do with film is put it into one of those schemes, and it gets sent for recycling. It's better than composting because you have massively increased the chance of that recycling of that material.

Ultimately the only difference between this bag and the other is the person that's buying it. They're the person that has the control to recycle (or not).

If you do the work to ensure your packaging is most recyclable then as the customer they have the choice to recycle it, and you have to give them the information as to how they can do it.

And that message?

You know, it was never coming from a judgmental point of view. It's just I think it's a really good challenge to look at packaging – it’s a fascinating one."


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