Don't put compostable plastics in green bin, Metro Vancouver says

Just because an item says it is compostable, doesn't necessarily mean you can toss it in your green bin. And as Vancouver considers requiring all single-use items be recyclable or compostable, some in the industry say the infrastructure isn't there yet.
Metro Vancouver says do not place compostable plastics like straws and paper-based dinnerware in your green bin. (CBC)

The take-out cup and straw from your local juice shop may say "compostable" on it, but that doesn't necessarily mean you can toss it in your green bin.

"There seems to be confusion about compostable plastics," said Karen Storry, a senior engineer with Metro Vancouver.

"Even if they are labelled compostable, they may not be accepted at local facilities."

Compostable products on the market include things like straws and other dinnerware made from either paper or PLA- polylactic acid- which are made from natural resources like corn and look like traditional plastic.

Storry says paper based products can be put in curbside collected green bins, but she doesn't know of any of the region's municipalities that accept the plastic-looking compostable items and that goes for bags too.

Metro Vancouver says businesses selling items in compostable containers need to make sure the company collecting their organics can process that type of material. (David Donnelly/CBC)

These items are growing in popularity as cities like Vancouver are looking at requiring all single-use items be recyclable or compostable, and businesses look to make a smaller environmental impact.

In order for compostable plastic containers to break down they need specific conditions at the composting facilities, including high temperatures, bacteria to quickly break them down and a longer period of time to complete the process.

Storry says there are only a few facilities locally that can do it.

That means it is up to businesses who have to contract their own green bin collection company to make sure they can.

"For businesses that are switching to compostable plastics," said Storry, "It is important for them to check to make sure that, at a minimum, it is accepted."

'There is no clear science to say it is remarkably better'

In a statement, the City of Vancouver says the facilities that handle its curbside green waste will filter out the compostable plastics and send them to the dump.

The question is what happens to them then under conditions very different than a compost heap. Lacking in high temperatures and the bacteria that eat away and breakdown compostable items.

"When we talked to researchers and looked into the science of ... is it better in a landfill to have regular plastic or compostable plastic items, it was inconclusive, said Storry.

"There is no clear science that says it is remarkably better to have one or the other."

Compostable plastic should not be placed in green bins, according to Metro Vancouver. (Don Marce/CBC)

Compostable plastics are also not recommended for backyard compost bins, that likely don't get hot enough. And are considered contaminates and removed from recycling processes.

So,  what do you with the cup you just brought home? If you live in a strata, check whether the company collecting your buildings organics will accept them. You can also try taking it back to the store or restaurant you bought it from and make sure its green bin collector can process it.

'It's a bit of the wild west out there'

The Compost Council of Canada says while it believes these items are a good step, the lack of infrastructure is posing a challenge for the industry. The council is a non-profit that advocates for organics composting and represents facilities.

Executive director Susan Antler says facilities have to operate under strict conditions of what can be inside their end product before it is sold as compost, so they have to be extra cautious about what goes in, adding a traditional plastic straw can look just like a compostable one.

"The compost facility is saying we can't distinguish one from the other, so we don't want any," Antler said.

These straws look like plastic but are made from renewable resources like corn. (Don Marce/CBC)

The other issue, she says, is whether items being sold as compostable actually are. She says some companies have gone through the process of being certified to prove they will break down in compost facilities. But there are some who haven't, and she says the federal government should do more to verify the claims.

"It is a bit of a wild west out there, and so, that is why we are keen on saying certified compostable because then the company and product have invested in the process to say we are not going to do any harm in the compost process," Antler said.

"But at this point there aren't a lot of screens on that."

The other issue she says is funding. Recycle B.C. collects fees from any company that produces packaging of any kind and right now that money can only be used to pay for recycling programs.

Antler wants to see those funds put toward composting.

Metro Vancouver says this issue is one that will have to be looked at by all levels of government.


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