Buzz
Earth Day is upon us once more, acting as a yearly reminder to continue the crucial practice of reducing, reusing, and recycling to ensure a better planet for the future.
While many are familiar with the concept of separating specific items from the rest of their waste, the full process of modern recycling remains somewhat enigmatic. From understanding the recycling symbol to deciphering the numbers on plastic containers, there’s a lot to uncover about how your waste can be transformed into something valuable.
A Global Icon With Deep Environmental Roots
The iconic recycling symbol—three interlocking arrows forming a triangle, with one arrowhead pointing towards the tail of the next—was designed in 1970 by Gary Anderson, a student at the University of Southern California, as part of a competition for the first Earth Day. Each arrow in the emblem symbolizes a key step in recycling: collecting recyclables after use, breaking them down and remaking them, and finally packaging new products in the containers.
Initially created as an inverted triangle, the symbol was later rotated to the familiar pyramid-like shape we see today.
The Number Game
In 1988, the American Society of Plastics Industry introduced the use of numbers within recycling symbols on plastic containers to aid in sorting. The "Resin Identification Code" assigns seven numbers to categorize the type of plastic used in each container, with higher numbers representing less frequently used plastics.
Here’s a guide to understanding each of the codes:
1. Polyethylene Terephthalate (PETE/PET) Commonly labeled as "PETE" or "PET," this resin is primarily found in soda bottles and containers for both food and non-food products. When not used in containers, it's also known as polyester (yes, the fabric used in your jackets). It’s one of the most commonly accepted plastics in curbside recycling programs, though the amount of usable material left after recycling is quite small.
2. High Density Polyethylene (HDPE) HDPE, the second most common resin for plastic bottles, is a tough, durable material with strong chemical resistance. It’s the go-to plastic for products like milk and juice bottles, household cleaners, and trash bags. It's easy to break down and reform, which makes it highly efficient in recycling. Most curbside programs happily accept HDPE products.
3. Polyvinyl Chloride (PVC) PVC, discovered in the 1800s, is widely used in construction, especially for pipes and plumbing, thanks to its strength and resistance to chemicals. However, it releases toxic carcinogens when burned, making it less appealing for recycling. Consequently, most curbside recycling programs don’t accept PVC items.
4. Low Density Polyethylene (LDPE) This plastic is becoming more popular for products like squeeze bottles and grocery bags. LDPE plastics are strong, which is why they are often used as sealants. While it wasn’t initially accepted by curbside programs, LDPE is now more commonly recycled.
5. Polypropylene (PP) Known as one of the safest plastics available, PP is used for squeeze bottles, bottle caps, and straws. It's also used for reusable food-storage containers. With an extremely high melting point, PP is ideal for heat-exposed items. Like LDPE, more curbside recycling programs are now accepting products made from PP.
6. Polystyrene (PS) Often referred to as styrofoam, this plastic is not only extremely challenging to recycle, but it also releases harmful toxins over time into anything stored in it—and even more when burned. Commonly found in disposable trays, egg cartons, and cups, polystyrene is seldom accepted by curbside recycling programs due to the environmental hazards and recycling difficulties it presents. Simply put, it’s one of the worst offenders in the plastic world.
7. Everything Else There are many other types of plastics, but most aren’t easily recycled in curbside programs. This category serves as a catch-all for plastics that could potentially be broken down and repurposed, but are often better off being reused or reformatted in ways that don’t involve chemical processes. This includes materials like bulletproof plastic and large water jugs from office coolers, and it's typically excluded from curbside recycling programs.
Safety In Numbers
For those curious about which plastics are safe to reuse without risk, it’s generally accepted that HDPE (2), LDPE (4), and PE (5) can be reused multiple times for food-related items. These plastics are resistant to chemicals, do not degrade easily, and don’t leach harmful substances into their contents.
This story first appeared in 2013.
