It’s easy to think that plastic is plastic, but the truth is that there are so many types, and they all behave in different ways. Some are worse for the environment, and some are worse for our health. What’s a regular nonchemist to do? Read this plastics primer, for starters!
Make sure to download this printable PDF to keep this information handy in your kitchen.
Plastics by the numbers
If you look at most plastic packaging, you’ll often see a number (#1 to #7) in the middle of triangular arrows; that’s a resin code, and it tells us what type of plastic it is. Contrary to popular belief, this resin code is not a recycling symbol and doesn’t mean the item is recyclable.
#1 (PETE/PET)
A bit about it
Polyethylene terephthalate is often a firm plastic that’s used for single-use items such as water bottles.
Recycling
It’s relatively easy to recycle.
Health
It is thought to leach a suspected carcinogen called antimony, especially at high temperatures.
#2 (HDPE)
A bit about it
High-density polyethylene is typically a hard plastic (such as for medicine bottles, milk jugs, or detergent bottles) but other times is a bag, such as cereal box liners.
Recycling
Generally, firm #2 plastics are easily recycled, but box liners are less recyclable.
Health
Compared to other plastics, it is considered a safer option.
#3 (PVC)
A bit about it
Polyvinyl chloride is very challenging to identify, as it can be found in a variety of consumer goods and is often not labelled. It can be found in some, but not all, soft plastics such as shower curtains, rain gear, cling wrap, school supplies, and children’s toys, as well as pipes.
Recycling
Technically recyclable, but very rarely accepted except at specialty locations.
Health
PVC can leach numerous chemicals, including chlorine and phthalates (which are known reproductive toxins). Its manufacturing also releases harmful chemicals.
#4 (LDPE)
A bit about it
Low-density polyethylene is sometimes a hard plastic, but is known for being the quintessential grocery bag.
Recycling
Technically recyclable, but notoriously challenging, as it tends to get caught in sorting equipment and cause safety issues. Plastic bags are also considered a cheap material with little value and too much contamination, meaning that they’re often shipped abroad to countries such as Malaysia, which are now pushing back and refusing our plastic garbage. Plastic bags are not often accepted in curbside pick-up recycling programs.
Health
Compared to other plastics, it is considered a safer option.
#5 (PP)
A bit about it
Polypropylene is typically a hard plastic used for things such as yogurt tubs and food storage containers.
Recycling
Generally, #5 plastics are widely recyclable.
Health
Compared to other plastics, it is considered a safer option.
#6 (PS)
A bit about it
Polystyrene is often known as Styrofoam or foam. This lightweight material is used as packing material, takeout containers, some disposable cups, egg cartons, meat trays, and even yogurt containers. (Note that it doesn’t always look like foam.)
Recycling
Technically recyclable, but not always accepted except at specialty locations, where it may be densified to press out the air that makes polystyrene foam bulky to ship to processors.
Health
It has been shown to leach styrene and other toxins.
#7 (OTHER)
A bit about it
This category is a catch-all, so it includes all plastics not previously mentioned (including polycarbonate plastic—BPA).
Recycling
Technically recyclable, but very rarely accepted except at specialty locations.
Health
Since this is a catch-all category, it’s nearly impossible to say. For information about BPA, or bisphenol A, see the sidebar.
Are bioplastics better?
Bioplastics—plastics made from plants— and biodegradable plastics often pose as eco-friendly solutions.
Vito Buonsante, plastics program manager at Environmental Defence, explains that some plastics are made from plants, but this doesn’t make them biodegradable, and some are not bio-based but are still biodegradable. (Note that degradable just means it will break down into smaller pieces.)
Plus, compostable plastics require very specific conditions with light, microbes, and heat. They won’t break down in landfills, but also do poorly in the oceans. Typically, they require industrial composters, which consumers don’t have access to.
“Generally, bioplastics are a scam,” says Buonsante. “They cause a lot of confusion and give the wrong signal to people. In most cases, it makes things worse because it’s often not recyclable, but there’s no way to tell the difference between it and conventional plastics.” This means that the recycling will be contaminated and will all become garbage.
“We also need to consider the point of compost, which is to create new, high quality soil. Even if they can be composted, plastics don’t increase the value of the soil,” he says.
So, what do we do?
“Remember that recycling is expensive, and it’s a business—there needs to be a market to buy the product,” says Vito Buonsante, plastics program manager at Environmental Defence. Even though it is counterintuitive, virgin plastic is often cheaper than recycled plastic. Much of what we think is recyclable is not: as of 2015, approximately 6,300 metric tonnes of plastic waste has been generated globally, only 9 percent of which has been recycled.
The best advice is to refuse, reduce, and reuse when possible. Here are a few tips.
- When shopping, bring grocery shopping bags as well as cloth bags for unpackaged foods.
- Choose unpackaged foods, such as loose produce, bread from the bakery section, and bulk goods.
- Research recycling rules in your community so you know which products are best to purchase and how to treat the plastics you obtain.
- Make an “on-the-go kit” that includes a water bottle, travel mug, and cutlery.
Handle with care
When it comes to the health considerations of using plastic, it depends on how we treat it. Plastics are very sensitive to their environments and can leach estrogenic chemicals if they become stressed by heat or UV damage. New research is showing that most plastics—even the ones considered safer options—leach chemicals.
Refrain from washing plastics in the dishwasher or microwaving or boiling plastics. According to Vito Buonsante, “microwave-safe means it won’t melt, but not that it’s safe.”
See also BPA Explained for more valuable insights!
