What is the common number 6 plastic?

The Truth About Plastic #6: Polystyrene and the Recycling Myth

When you see a tiny "6" inside the recycling triangle on a plastic item, you're looking at polystyrene (PS), commonly known as styrofoam—though that’s technically a brand name. This type of plastic is widely used in disposable coffee cups, takeout containers, packing peanuts, and even some disposable cutlery.

Despite the recycling symbol, polystyrene is one of the least recycled plastics in the world. Why? It’s lightweight but bulky, making transportation and storage inefficient. More importantly, recycling it requires significant energy to compress and process, which most municipal facilities aren’t equipped to handle. As a result, plastic #6 is rarely accepted in curbside recycling programs and often ends up in landfills or the environment.

Even when collected, polystyrene breaks down into microplastics over time, posing long-term ecological threats. It’s also derived from fossil fuels, contributing to carbon emissions from production to disposal. Some specialized facilities can recycle it, but they’re few and far between—making large-scale recovery impractical.

Because of these challenges, environmental experts often recommend avoiding polystyrene altogether. Many cities have already banned single-use foam products in favor of compostable or reusable alternatives. As consumers, choosing products in #1 (PET) or #2 (HDPE) plastics—which are more commonly recycled—or better yet, opting for glass, metal, or reusable materials, can make a real difference.

In short, that little number 6 might look recyclable, but in practice, it rarely is. Knowing this helps us make smarter, more sustainable choices—one foam cup at a time.