ALUMINUM, GLASS, OR PLASTIC, WHICH SHOULD YOU FAVOUR?
March 1, 2020
A jar of tomato sauce, can of tomato sauce, and plastic bottle of tomato sauce all sit on a shelf at the grocery store. There may be many aspects to consider about these different products when deciding which to purchase. Maybe the brand name, ingredients, if it is organic, where it was made, the price. But have you ever considered the packaging?
Packaging of products is important to consider, especially through the transition to less packaged foods. Some packaging can be just plain difficult to avoid unless you have time to prep the entire basis of your stocked cupboards. So when we come across a packaging decision between products that are otherwise the same, how should we choose?
Food for the pantry is usually packaged in one of three materials: Glass, plastic, and aluminum. Each is recyclable, meaning they can be reprocessed and turned into a new raw material again. Each is also convenient in the way they are able to preserve food and prolong shelf life while also cutting out extra prep time for us while cooking. Each of these materials also has positive and negative environmental impacts that are essential parts of food prep consideration. Knowing how each material is harvested, processed, and recycled can help us make more informed decisions about which food packaging we choose to support.
Aluminum is made from a material called Bauxite Ore (essentially a type of rock), which is harvested from the soil of tropical and subtropical regions using a process called strip-mining. The harvest of bauxite can be quite detrimental to the ecosystems and can also be energy intensive. Strip-mining isn’t always unsustainable, but without doing prior research on what resources companies are using for their products, it would be hard to know if it was harvested economically or not.
Although this may not seem like a great start, aluminum does have a lot of positives to the material once it is in circulation. Aluminum can be recycled almost without losing any material in the process, and it can be continually turned into new products over and over again, indefinitely. In fact, 75% of all aluminum ever produced is still being used and reused today.
What about the other 25%? Well, this is approximately the amount of aluminum that ends up in landfill or wild spaces. And of course if material like this ends up in a place where waste collects, sits, and leaches chemicals, it obviously never makes it to a place where it can be made into something new and is therefore a waste of good bauxite.
Recycled aluminum is often mixed with new raw material when it is created into other packaging, and using the recycled aluminum saves about 90% more energy in processing compared to using the raw bauxite material and turning it into alumina.
Glass is the front face of the zero waste community, partially for good reason, but it does have some downfalls too.
First off, glass is made from melting sand (or silicon dioxide) at extremely high temperatures of about 1700 degrees celsius. It is essentially changing into liquid sand that turns transparent when cooled. When glass is being made, new clean sand is mixed with recycled glass and soda ash and limestone. Those last two ingredients reduce the melting point to help save energy and strengthen the material while creating new glass.
Our everyday glass used for bottles and packaging is known as soda-lime-silica glass. Like aluminum, it can be recycled endlessly without any deterioration and adding recycled glass into the mix lowers energy and carbon dioxide release in the creation process. It also reduces the need for new material, for every 1kg of recycled glass, it replaces 1.2kg of raw silicon dioxide.
However, getting recycled glass in a ready-to-melt form requires a lot of processing and there is often a line up for glass sandblasting. Single stream recycling, where all recycled material is collected together, also makes the glass processing a little more intensive through sorting and sending the crushed glass to be processed. These details make glass more expensive to produce causing the processing facilities for new glass creation to be limited and is also why recycling facilities have to send glass to other locations instead of sourcing it locally.
Glass too has its pros and cons, but one last note to add is how easily it can be reused and repurposed before actually sending it to be recycled. If you are using your glass resources correctly, you may never have to buy a container or glass sealing jar again.
Lastly, comes plastic, made from polymer which is created from oil. Plastic is both one of our greatest and most devastating inventions. It has allowed us to have many medical and technological advances, took some of the pressure off of the wood industry, and made products more affordable. But it also created a life of disposability, pollution affecting all parts of the world, and toxins that leach into our food and natural environment.
Every year about 17 million barrels of oil are used to make new plastic, which releases more greenhouse gas emissions than over half a million vehicles on the road for a year. Recycling plastic and using it for product creation takes much less energy than producing plastic from raw material.
Plastic is very cheap to produce compared to aluminum and glass, which means it’s a lot more popular for a packaging material among large companies. This also means that through recycling, it doesn’t bring in much revenue and can cause some major issues through the variety of different plastics that can be created from polymer.
Plastic packaging often has a number on it somewhere that represents the type of plastic it is through its chemical makeup. A lot of those plastics can not mix together when being melted down into new material. Everytime plastic is made into new plastic, it also degrades. Low grade plastics such as that of a plastic water bottle (made from polyethylene) can only be recycled up to ten times before it can only be made into string for use in clothing. After that, it can no longer be recycled to be turned into new material.
The material value of plastic always decreases, right from the first time it is created into a bottle, and only 9% of all plastic worldwide is recycled, meaning most of our plastics end up in places it shouldn’t. After use, we see plastic as valueless, which is the reason the current production rate of new plastics will out pace that of recycling.
Which Should You Choose?
Taking into consideration all the benefits and consequences of buying aluminum, glass, and plastic, I’m sure you might be thinking the ideal choice is actually to pass on all three! But unfortunately that is just unrealistic. We can all do our part to reduce our use of packaged products, and still even I find I buy many canned, jarred, and bottled products for my pantry.
Every product we use affects the planet in some way, through habitat invasion, mining of raw materials, their carbon footprint, and energy of material production. Which product you choose to purchase will reflect what you prioritize most, aluminum for example being a material that is easy to recycle on a local scale. Or glass, having the lowest material extraction impact and no chemical toxins leaching into the environment. Or even post-consumer plastic packaged products supporting reuse and recycling efforts. The difference between aluminum, glass, and plastic is in the way we value the product packaging in its afterlife, once the food product has been used and we are left with only what it came in.
Aluminum is seen as a highly recyclable product (which it is) and is fairly simple to understand that it is recyclable. All aluminum is essentially the same and there are no confusing numbers on the packaging making us wonder what to do with it.
Glass is extremely reusable and could take on many different lives after it holds a sauce or beverage without us having to transform the material. We see it as a useful container that looks, for the most part, quite visually appealing.
Plastic on the other hand is created into so many different shapes, sizes, colours, and qualities used for so many things that we view it as valueless. Bags and dressing bottles seem non durable for more than one use. Straws and cups are convenient for a second and then we probably won’t use them again. We can’t make something cool and resell it. We don’t want to reuse it because of the chemicals some plastics carry. It has become so normal for a cheap product to be sold in a bottle, that the value lies in the product and never in the packaging too. Therefore once the product is gone, so is the packaging’s value, and plastic is viewed as if it can not be used again… for example, recycled.
If we value plastic differently, our plastic pollution problem may not be a problem of the future.
Although there are differences between aluminum, glass, and plastic, their afterlife should be treated the same. Hopefully this comparison study shed some light on the production of each material, providing the opportunity for more informed purchasing decisions. If nothing else, reducing our use of all three when we can is the key to a world with less waste and appreciation for what these materials provide us.