Plastic comes in many shapes and sizes – where did it come from and where will it go? Each year around 252,000 tons of plastic ends up in New Zealand plastic landfills. Plastic bottles take 400 years to degrade because it slowly disintegrates. Plastic is either recyclable, non-recyclable, biodegradable, or something in-between. Plastic is made from hydrogen and carbon atoms that are processed into a series of molecules called polymers. ‘Poly’ means many, hence why the scientific name behind plastic starts with ‘poly’.
Bio-based plastics are made from natural and renewable resources such as wood, sugar, starch and vegetable oils. They are increasing due to environmental issues such as the depletion of fossil fuels and a preference for renewable resources. ‘Biodegradable’ means the plastic breaks down naturally and is less destructive to the environment compared to normal plastic, however, it is important to note that biodegradable is an ambiguous term. New Zealand does not have any standards set for biodegradable plastics or compostable plastics so universal standards are often used as a guideline for an acceptable standard of biodegradable – no impact on the soil, composting or agriculture.
Plastic production uses around four percent of the global oil production that is created with energy from fossil fuels. Plastic that ends up in a landfill leaves environmental damage, and is a waste of resources that could be used to create fuel, heat and electricity. Modern technology is exploring ways to utilize plastic landfill waste however is still a long way from being able to handle the plastic produced let alone begin reducing existing plastic landfills. Due to global issues such as the depletion of fossil fuels, people need to understand their product waste. Here is a list of the different plastics in New Zealand, and their respective recycling codes.
- Plastic composition – polyethylene terephthalate (PET)
Products are lightweight and clear, and products look clean and pure. There are advantages being that they do not break easily and maintain the shelf-life of edibles. PET is partially bio-based but not biodegradable.
Applications: soft drink bottles, sports bottles, food trays, condiments/ food jars. Because it does not react to food and water, it is strong and durable, and comes with a low price that makes it a feasible solution.
Remade: into RPET that is the most widely recycled plastic in the world that is used for products such as fabric for T-shirts, long underwear, athletic shoes, luggage, sheet and film, sweaters and fibrefill for sleeping bags and winter coats.
- Plastic composition – high-density polyethylene (HDPE)
Products are sturdy, translucent or opaque, and can be easily recycled.
Applications: water bottles, milk bottles, cleaning products, personal cosmetics, laundry detergent and bleach bottles.
Remade: toys, soda bottles, trash cans, traffic cones.
- Plastic composition – poly vinyl chloride (PVC)
Products are made from salt and oil – a composition that is the most produced plastic-synthetic in the world.
Applications: packaging/ wraps such as takeaway containers, chemical dispensers, plumbing pipes, flexible packaging. It is biologically, chemically, water and fire resistant that makes it suitable for many products.
Remade: PVC is rarely recycled due to the additives such as phthalates and dioxins, or the pipe material is reused into other pipe applications such as drainage coil. As PVC can rarely be reused most of it is dumped into plastic landfills.
- Plastic composition – low-density polyethylene (LDPE)
One of the most commonly produced plastics.
Applications: stretch film, shrink wrap, bubble wrap, zip-lock bags, grocery bags, squeezable bottles.
Remade: floor tiles, compost bins, trash cans, paneling, furniture, shipping envelopes, garbage can liners
- Plastic composition – polypropylene (PP)
Products are semi-rigid, translucent with good fatigue resistance.
Applications: hard containers, medicine bottles, takeaway containers, bottle caps, refrigerated food containers, yogurt and margarine containers, drink cups.
Remade: Mixing bowls, cases, oil funnels, shipping pallets, spatulas and cutting boards, watering cans.
- Plastic composition – polystyrene (PS) and expanded polystyrene (EPS)
Applications: styrofoam cups, plastic plates/ cutlery, food containers, small hard-wearing bottles.
Remade: insulation, picture frames, holdings, egg cartons, foam protective packaging.
- Plastic composition – other (composite)
Products: composites are made from two or more different materials that are blended together to produce a new material.
Applications: milk/ fruit juice cartons, roofing, oven bags, cases.
Poly Lactic Acid (PLA)
A natural, plant based plastic that is made from natural resources, such as corn. This falls under the bioplastics industry that is low-carbon but uses natural resources such as corn. Compared to petroleum-based plastics, PLA can be constantly renewed and creates 63% fewer greenhouse gases. However, the label ‘biodegradability’ has different functions for different PLA plastics – some biodegrade with oxygen and ultraviolet radiation, others compost, and the rest require industrial composting processes. It is important to remember if the bio-plastic requires ultraviolet radiation to degrade it is unlikely to happen at the bottom of a plastic landfill.
Applications: coffee cups, lids, straws, disposable utensils, takeaway containers.
Remade: plant-derived plastics used in food packaging as ‘biodegradable’ ‘compostable’ or ‘recyclable’ (providing it is in a controlled environment).