Nangs. Those little steel bulbs of nitrous oxide you drop on the ground because littering at a festival isn't littering, right? Because festivals employ people to pick up nangs and then recycle them… right? Wrong. Because although they do get picked up, and although nangs are made from very recyclable steel, they're not recyclable.
"The problem is that in order to recycle them, a scrap metal dealer needs to be able to crush them," explains Amie Green, owner of Green Chief Recycling. "But if you have just one unopened canister, it will actually cause an explosion. So despite the material being very valuable, it poses too much of a risk."
Green Chief Recycling is a business based in New South Wales. They're contracted to clean up after all the big festivals, and Amie explains that on average she and her team will collect somewhere between 500 kgs to a tonne of empty nangs. And then, because nangs are too dangerous to be recycled, they usually end up in landfill.
This in itself isn't an issue. Nangs are made from fairly inert materials so they have little environmental impact. But as Amie explains, "The problem here is the amount of energy raw materials used in creating the canisters, for only one purpose."
It takes a lot to produce a container that can safely hold highly pressurised gas. For this reason, nang bulbs are made from 3mm thick galvanised steel. Notwithstanding the fact that so much steel could go to better use, the smelting process produce heaps of greenhouse gas. According to the Intergovernmental Panel on Climate Change's Fourth Assessment Report, one tonne of steel can produce 1.25 to 3.8 tonnes of carbon dioxide. With nangs being the 7th most popular drug in the world, a lot of CO2 is pretty needlessly going into the atmosphere.
Then there's all that steel we're putting in the ground. Based on Amie's weight estimates, it's not unreasonable to assume that Australia is burying at least 10 tonnes of spent nang canisters every year, which is equal to the weight of around seven cars. Nangs are also galvanised, meaning they're coated in zinc to prevent them rusting, which gives them a lifespan of between 50 and 75 years.
The question is, will any of this change any time soon? Amie says that she's found one person who can recycle them, but they're not loudly advertising their services. And not knowing which recyclers are nang-ready means that most scrap metal dealers refuse to take nangs, as well as any scrap that has nangs mixed in.
"After festivals we have a lot of scrap metal to deal with, so we actually have separate [nangs] from the rest of the recycling. It's really sad, especially when you consider the amount of time and manpower used to separate them, that they just end up in landfill."
So if you feel so inclined, and want to make up to $2 a kilo, call around some recyclers and ask if any will take your spent nangs. You could get rich. Otherwise, in the very least, just stop doing nangs and talking about the state of the world. Because you're not helping.
Follow Sam on Twitter