What's better, glass, plastic or aluminium?! It's not the one you think...

Is glass really all it's cracked (hah) up to be?

This is the transcript for the podcast episode. If you prefer to listen, you can here: https://open.spotify.com/episode/1n14vX73EwrLalPEogsDGX?si=Ixy8KPNHSFq3fABwGXSoHA (and the video is on our YouTube channel).

Welcome back - I had a couple of weeks off this pod to focus on the business one, not through any real plan, but because I got kinda overwhelmed with all of the stuff I had to do. So sorry, but we're back and this is one of my fave episodes. It's taken a lot of research, and a lot of that reading made me really quite angry about the way we (read: corporations) do things, but it was very interesting. Because today, we are talking about what is actually better for our environment; plastic, glass or aluminium packaging. And one of those is the absolute worst. It just may not be the one you think it is... So to put together this pod, I used a tool called a life cycle analysis - or LCA. These reports looks at all the inputs, and outputs throughout the er, entire lifecycle of something, in comparison to something else.

Now this pod is going to engender lots of comments along the lines of 'but what about plastic in the ocean', which is absolutely a massive problem. But it's not the only problem associated with these packaging options, but it's one people almost exclusively worry about. Because we see it. We see it in sad pictures of turtles and seabirds. We see it in rivers clogged with rubbish. And that is devastating of course, but it means we don't look further upstream at the energy and resources used to make the alternatives, which lead to just as much destruction, in fact, arguably more. It is difficult to quantify the cost (in not just money) of plastic ending up in our environments, and of course, our bodies because we don't yet know with certainty the harm it's causing.  But it does mean these LCAs do struggle to include this. One LCA does contain a way to measure this issue, which I will get to. But this pod is going to focus on the whole thing - so you can make much more informed decisions, next time you buy a drink. Because when we know more, we do better. A lot of you probably think reaching for the glass bottle over the plastic one is the better option. Well, it's not. Now before you get outraged - listen on.

We use 2 billion drinks containers here in Aotearoa - every year.

Today, PET or polyethylene terephthalate (which is a plastic) accounts for about 70% of that number. I'll rip the bandaid straight off. All of the LCAs I read (and I read all I could find), said that plastic bottles have a lower impact than glass when considering all inputs.


Specifically, out of the two, R-PET, or recycled PET, is the best option, followed closely by virgin plastic, followed by recycled glass, then virgin glass.

Glass is the worst option because it requires so much energy to make, recycle and it's weight makes it energy intensive to transport. It has the highest (by a country mile) acidification potential which is bascially it's contribution to things like acid rain, which is yes, still a concern we just don't talk about it much. Essentially it means it contributes things like sulfur dioxide, nitrogen oxides and dioxides to the air. These are bad.  Worse still, glass has the biggest global warming potential - or the rate that it contributes to climate change.  It has the greatest impact on eutrophication - which is essentially overly enriching water sources with nutrients - like how we talk about nitrates in our water. It leads to algal blooms and dead zones and huge damage to both fresh water and oceans. It is also considered the most toxic to human health, aquatic health, and terrestrial health. Now when I say glass has the highest impact - in each of those categories, glass is enormously impactful versus the next closest - which is recycled glass.

So how much glass is recycled?

21% of glass is recycled globally but it's better for drinks containers at 32%.

About 42% of the glass collected Aotearoa is recycled into bottles - this is predominantly in Tamaki Makaurau Auckland. Elsewhere it's downcycled into things like roads and paving stones.

So yeah. Glass... ain't good.

However, if we considered ONLY disposal, which as I have mentioned most people do, glass is the best option. But we really need to move on from that consideration.

One of the LCAs I have makes use of something called a Marine Litter Indicator, taking into consideration the possibility of the packaging ending up in our oceans.

So what is that possibility?

Annually, we produce about 350m tonnes of plastic waste.

In 2019 globally, we recycled 9% of all plastic, incinerated about 20%, mismanaged 25% and landfilled the remainder. Mismanaged effectively means 'litter'. 

About 0.5% of that plastic waste ends up in the ocean. That figure sounds small, but its still about 2.5 million tonnes of plastic. And it is estimated that is lower than in reality, but it's a hard thing to measure.

So chances are good that the plastic will end up in the landfill, or our environment somewhere, where of course it doesn't break down, but gradually breaks up into micro plastics. Which are now found everywhere on earth.

BUT, if we look at it's earlier lifecycle, plastic is better than glass in every other measure. Even if you reused a glass bottle 8 times, which statistically doesn't happen, it still uses more resource per use, than using a plastic bottle once.

So that's both simple, and not at all simple.

Because glass sucks throughout it's entire lifecycle, though yes, recycled is a little better and recycling rates are... okay ish.

Plastic is vastly superior in every measure except disposal.

I think the obvious solution here is to make manufacturers and brands using plastic pay a small tax (it could be less than 1c per unit) to build more infrastructure. I remember having a chat with then Prime Minister Jacinda Ardern and asking why that wasn't happening. I honestly can't remember her answer, but I do remember being disappointed by it at the time - I thought it was rather noncommittal.

Anyway, it is worth adding into the discussion here that we cannot recycle our way out of the plastic crisis. Three major reasons; firstly, the quantities are breathtaking and we don't have the infrastructure. Two, is that it doesn't stack up commercially to do so, so why would anyone build that infrastructure because it's not a viable business and three... most plastic is not really recyclable as it loses it's properties as it goes through the process and becomes much less useful. Oil companies knew this was the case decades ago but put millions of dollars into PR campaigns encouraging us to recycle to - guess what - make us feel guilty for the plastic pollution! So yeah, just another evil thing those absolute pieces of shit did.

Is there a conclusion to be drawn from this? I think so.

If you are going to buy a bottle of drink because you need one, go for plastic. Then reuse it and reuse it and reuse it. Or, if you are hell bent on glass, try find one that has recycled content then reuse it, reuse it, reuse it. Seeing a theme?

Someone will point out the health concerns associated with plastic bottles - well these are hard to quantify as we just don't know, so yeah, something else to be mindful of for sure, but glass has those health implications too - it's just further up the line and you don't see it.

Now, if we look at aluminium, the 'infinitely recyclable' miracle metal, the stats are much better. But, it's a wee bit complicated.

75% of all aluminium ever made is still in use today, which is a fantastic success story.

Let's narrow it down to drinks cans.

Globally, we use 180 billion cans every year. 

Making cans out of recycled aluminium uses 95% less energy than mining the ore and making virgin aluminium.

Your can is usually made of between 60-70% recycled content. 

The international aluminium group says 50% of all cans are recycled, which is actually a decrease in recent years and is heavily dependent on infrastructure near you.

Without question, aluminium is a superior material - even when it's recycled. For those thinking about the plastic liner on the inside - as the recycling process reaches very high temperatures the plastic is effectively  removed.

It's not perfect.

Aluminium containers score worse than plastic (but still better than glass) when we look at things like marine and freshwaste ecotoxicity due to the mining and processing and they are a smidge worse in human toxicity measures, but overall, a better choice.

There are stats for days honestly, so I've picked the most relevant and included the LCAs in the show notes for you to read should you want to know more.

So, clear as mud?

If it was me, and I needed a drink, I'd go for a can first, then a plastic bottle and I'd skip the glass entirely. And I say this as someone who is clearly, not a fan of plastic. I've largely dedicated my professional life to giving people better options. But it's not the worst option when you bear the whole thing in mind.

Most importantly though, I am trying to point out that none of them are 'good'. Including aluminium cans.

At the end of the day, reuse is the best option. Obviously.

But this is also a huge behavioural trend for many. This debate right here is why I decided to create Incrediballs.

I thought briefly about retiring after I quit Ethique. I thought about spending time on the dying coral reefs, buying a sail boat and floating around in my favourite place in the world - the ocean. It took less than an hour to realise that is absolutely not what I wanted to do, and that I would pursue this idea of packaging-free drinks. Because we need to change this and I believe I can help. Because I do believe Ethique helped change the beauty industry and whilst the industry still needs to change a shitload more, the conversations are happening. We need massive change in the way we consume, not just knee jerk reactions like switching from plastic to glass. Cus if we all did that, man would we be in for a world of pain.

And for those listening along wondering why I don't just tell people to drink water - and out of their tap, I am an idealist, but I understand people. People don't want to change. They don't want to give stuff up. They want a variety of drinks. They want healthy options. Everyone just drinking water isn't going to happen. Not to mention millions of people have greater access to coca cola than they do to safe tap water (which is a travesty I won't get into). Telling people to stop drinking other stuff is like telling everyone to stop travelling, or to stop eating meat. Yes, we should, but people can't, or won't. So we have to work within the bounds of reality, and make those realities less impactful, and more equitable. 

So the takeaway is this.

When we consider the entire lifecycle, all bottles, cans, jars suck at least a little. Some, a lot more than others. Unfortunately, glass seems to be the worst - across all measures - unless you solely care about disposal. And we know better than that now right?

So the best option is to do away with the container entirely. And grab an incrediball. Yes, this has secretly been an ad for Incrediballs this whole time. Okay, not really. But you can see the sense in them now right...?

For further info, links in the notes below.

Thanks for joining me, now go spread the word!