What Do Those Recycling Symbols and Codes Mean?

iStock.com/ChrisSteer
iStock.com/ChrisSteer

Earth Day is here again, serving as an annual reminder of the need to reduce, reuse, and recycle our way to a better planet.

When it comes to the last part of that familiar three-”R” mantra, most people know enough to separate certain items from the rest of their garbage, but much of our modern recycling routine remains a mystery. From the recycling symbol itself to what those numbers on plastic containers actually mean, there's a lot you can learn from your trash before it becomes someone else's treasure.

An International Symbol With An Earthy Origin

The universal recycling symbol—three folded arrows that form a triangle, with the head of one arrow pointing to the tail of the next—was created in 1970 by University of Southern California student Gary Anderson as part of a contest tied to the very first Earth Day. Each arrow of the design represents one of the steps in the recycling process: collecting the recyclable goods after use, breaking them down and reforming them, and then packaging new products in the containers.

Originally designed as an inverted triangle, the symbol was later rotated to the pyramid-like orientation commonly used now.

The Number Game

The American Society of Plastics Industry first began using numbers inside the recycling symbols on plastic containers in 1988 as a way to assist with sorting them. The "Resin Identification Code" uses seven numbers to identify the type of synthetic material used to manufacture the container, with the higher numbers representing less commonly used plastics.

Here's a primer on each of the codes:

1. Polyethylene Terephthalate (PETE/PET)
Usually accompanied by the letters "PETE" or "PET," this resin is generally used for soda bottles and other containers for edible and non-edible goods. When it's not being used to manufacture containers, you might recognize it by another name: polyester. (Yes, it's the stuff that insulates your jackets.) It's also one of the most widely accepted forms of plastic in curbside recycling programs, though the amount of useable material available for new products after breaking down this plastic is relatively small.

2. High Density Polyethylene (HDPE)
The second most widely used resin for plastic bottles, HDPE is a stiff, strong material with a high resistance to chemicals, which has made it the go-to plastic for food items like milk and juice, as well as household cleaners and trash bags. It's also easy to break down in the recycling process and easy to reform, making it one of the most efficient consumer plastics. Most curbside recycling programs have no problem with accepting products made from this plastic.

3. Polyvinyl Chloride (PVC)
First discovered in the 19th century, PVC is commonly used in building materials today—especially pipes and plumbing material—due to its strength and chemical resistance (although it's occasionally used for some household products). It has a nasty habit of releasing highly carcinogenic toxins into the atmosphere when it's burned, so recycling is a significantly less appealing option for PVC disposal, and it's usually not accepted by curbside recycling programs.

4. Low Density Polyethylene (LDPE)
This plastic is becoming more common today, especially for manufacturing squeeze bottles and grocery bags. Plastics made from LDPE are usually very strong, and they're regularly used as sealants because of this quality. While they weren't included in curbside recycling programs at first, plastics made from LDPE are now becoming more commonly accepted.

5. Polypropylene (PP)
Regarded as one of the “safest” plastics produced today, PP is generally used for squeezable bottles, bottle caps, and straws. Along with LDPE, it's also used for food-storage containers that can be reused over time. It has an extremely high melting point, so it's one of the best consumer plastics for items that will be exposed to heat. Like LDPE, it's becoming more common for curbside recycling programs to accept items made from this plastic.

6. Polystyrene (PS)
More commonly known as styrofoam, this type of plastic is not only notoriously difficult to recycle, but it's also been shown to leach dangerous toxins over time into anything packaged in it—and even greater amounts of toxins when it's burned. This is the resin usually found in disposable serving trays, egg cartons, and cups, and it's rarely accept by curbside recycling programs due to the danger it poses and the difficulty of recycling it. Basically, this is the worst of the bunch.

7. Everything Else
There are countless other plastics, but very few of them are easily recycled in curbside programs, making this category the catch-all for everything that could conceivably be broken down and reformed, but might be better off reused or reformed in some way that doesn't require a chemical process. This category encompasses everything from bulletproof material to those large water jugs on office coolers, and is rarely included in curbside recycling programs.

Safety In Numbers

For anyone wondering which plastics are safe to reuse in their current form, it's widely accepted that HDPE (2), LDPE (4), and PE (5) can be reused multiple times for edible items, as they're generally resistant to chemicals, haven't been shown to degrade, and don't leach dangerous substances into their contents.

This story first ran in 2013.

2624-Year-Old Cypress Tree Discovered in North Carolina Swamp

iStock/earleliason
iStock/earleliason

National Love a Tree Day on May 16 is a day to appreciate all the world's trees, but a bald cypress recently identified in North Carolina is especially deserving of recognition. As Live Science reports, scientists date the tree to 2624 years old, making it one the oldest living non-clonal trees on Earth.

For their study, recently published in the journal Environmental Research Communications, a team of researchers studied the rings of trees in North Carolina's Black River swampland to learn more about climate history in the eastern United States. Bald cypresses are known to have impressive lifespans, but after analyzing specimens in the Black River's Three Sisters Swamp, an area that's notable for its long-lived trees, the scientists discovered that cypresses can grow to be even older than previously believed. The 2624-year-old cypress tree they found predates the Great Wall of China and the Roman Empire. Other remarkably old trees, including a 2088-year-old cypress, were also identified in the same grove.

The North Carolina cypresses are old, but there are other types of trees that can grow to be much older. Clonal tress are genetically identical plants that reproduce asexually from a single ancestor. Old Tjikko, a clonal tree in Sweden, has a root system that dates back 9550 years.

Despite all that North Carolina's bald cypress trees have endured, their lives are under threat. The swamp where the 2624-year-old tree stands is located just 6.5 feet above sea level, which means that floods driven by climate change could damage its habitat. And though the grove is in a protected area, industrial runoff and logging that's happening nearby could impact the trees' health. North Carolina is considering establishing a Black River State Park where the trees grow to further protect the ancient natural wonders.

[h/t Live Science]

This Beverage Maker Lets You Enjoy Carbonated Drinks Without Hurting the Environment

Sparkel
Sparkel

Whether you're preparing breakfast before you head off to work or looking for something to wash down lunch, procuring the perfect beverage is vital. If it's a carbonated drink, though, with that comes the carbon dioxide emissions that arise every time you hear that classic "fssst" sound from cracking one open. These emissions are actually quite harmful to the environment.

But thanks to the newly unveiled Spärkel, curating carbonated drinks can be done without using CO2 or any artificial ingredients.

"If you walk into any grocery store, the explosion in the popularity of sparkling drinks is plain to see with more choices and flavors than ever before, but why buy off-the-shelf when it is healthier, cheaper, and more fun to create your own drinks at home?" Darren Hatherell, CEO of Spärkel, said in a press release. "With Spärkel, we created a system that lets people use the freshest ingredients and convenient carbonation process to experiment and unleash their creativity in a way that is kind to their wallet and the environment."

Users can place any kind of ingredients they wish—berries, citrus, cucumbers, etc.—along with their drink of choice—water, tea, cocktails—into the 25 oz. (750 mL) bottle and choose what level, from one to five, of fizz they'd like to have added to their drink. The sealed chamber generates CO2 naturally from a sachet of Spärkel Carbonator powder, which is "made of a special granulation of citric acid and sodium bicarbonate." The CO2 bubbles are cycled through the liquid, and within a couple of minutes, you have a completely personalized sparkling drink.

On top of all that, the beverage maker is suitable for any number of usages from water and juices to cocktails. It also comes in nine different colors—black, white, gray, yellow, orange, red, blue, green, and pink—so it can match up with whatever kitchen palette you have.

To get your hands on the Spärkel, check it out on Indiegogo, where it's available for a pre-sale price of $59.

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