"Green" alternatives to throwaway plastics (part 2 of 2)

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2020/01/15 "Green" alternatives to throwaway plastics (part 2 of 2)

"Green" alternatives to throwaway plastics don’t always break down in sea water. But could they help to fix our food waste problem? (part 2 of 2)

Source from: https://www.bbc.com/future/article/20191030-why-biodegradables-wont-solve-the-plastic-crisis

Bioplastics might not solve our marine plastic pollution problem, but they are well suited to tackling another big environmental problem: food waste
While thin compostable plastics like carrier bags might break down in the ocean, the thicker and more robust PLA used to line coffee cups and make cup lids, clear plastic tumblers, drinking straws, and other food packaging is expected to act like traditional plastic in seawater, and won’t break down at all. So, are companies switching to biodegradable plastics that might not break down in the sea ‘greenwashing’? Not necessarily. These plastics might not solve our marine plastic pollution problem, but they are well suited to tackling another big environmental problem: food waste.

Cleaning up our act
The biggest potential area of impact for compostable plastics is in food service. From coffee cups to sandwich packaging to takeaway containers, putting food in compostable plastics means that – in an ideal world, at least – the plastic and any food waste still stuck to it can be composted together. It’s a triple win: reducing the amount of plastic being sent to landfill, preventing recycling from being contaminated with food, and at the same time making sure food waste is returned to the soil, not left to rot in landfill where it will release methane.

David Newman, managing director at the Bio-based and Biodegradable Industries Association (BBIA), says that he’d ideally like to see everything from tea bags to fruit stickers to condiment sachets have to be compostable by law, so that much more of our leftover food and the plastic it comes with can be processed at the same time. By reducing the amount of traditional plastics that contaminate food waste, we can at least ensure that some of that wasted food is eventually used as compost, rather than ending up in landfill or incineration.
There are some other applications suited to biodegradables, too.
Traditionally farmers have used polyethylene mulch sheets over crops to prevent weeds growing and to conserve water, with around half of this plastic ending up in landfill after it’s used. But since 2018, a new European biodegradability standard for these mulches means that farmers can buy plastic that they can plough back into the field safe in the knowledge that it will break down and not harm the soil.
Industry, too, is beginning to use bio-lubricants used to keep machines running smoothly rather than fossil fuel-based ones. “They're increasingly made from plant-based sources,” says Newman. “
If they spill, and all machine oils eventually spill, then they will not damage the environment.”

A load of compostables are going to end up incinerated, and a lot of plastics are going to end up in composting plants, it's just the way it is for the next two years or three years – David Newman
But while mulches and oils might break down in the environment, we know most food packaging does not. So how do we make sure compostable packaging is actually composted?

Demystifying the process
First, we need to fix the plastic’s image problem. Newman says that message shouldn’t be, “We're going to stop plastic pollution by using compostables,” but rather, “We're going to help the quality of soil for sustainability in the long term improve by using compostables,” he says. “Oh, by the way, we may reduce some plastic packaging as well.”
But he admits industry needs to demystify how compostables should be treated in order for this to work.

A clearer labelling system, similar to the way recyclability is marked on food packaging, is in the works, but it will take a few years to be implemented, he says. “In the meantime, it's clear that a load of compostables are going to end up incinerated, and a lot of plastics are going to end up in composting plants, it's just the way it is for the next two years or three years.”

At the moment, the UK’s waste system isn’t set up to handle compostables, at least at the household level. Though in-vessel composting facilities exist that could process compostable cutlery, coffee cups and more, councils don’t collect these items, so consumers are left with no option but to put them in the general waste where they’ll head to landfill or incineration. Some local authorities take compostable carrier bags if they’re used to collect food waste, but at some plants those bags are removed from the food waste before it’s composted.

Closed-loop schemes with a dedicated collection for compostable plastics, like the one launched with Vegware in the UK Parliament last year, offer some hope. But even they run into problems: an investigation published by Footprint in July this year revealed that in its first seven months, Parliament’s scheme had to send all of its compostable plastic to be incinerated, largely because of high levels of contamination.

It’s a problem worth cracking. If we do figure out how to properly process them, compostable plastics could lend a helping hand when it comes to traditional plastic recycling too.
Separating out food waste and associated compostable packaging into a different waste stream would mean the remaining recycling is kept away from coffee dregs, tea bags and other contaminants. “When you've got your food mixed up with everything, as we have in [the UK], everything is difficult to recycle,” says Newman.

Progress made by countries like Italy – where single-use bags for produce and baked goods must be compostable, and can be recycled as part of widespread food waste collections – shows that solutions to some of our plastic problems are there for the taking. “If you get your food waste done properly, as they have in several countries, everything else becomes easier to recycle,” says Newman. The challenge is to get all of the pieces of the puzzle to slot into place.

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