This article was originally published in the Teton Valley News on November 6, 2014. It is republished with permission. 

Have you ever wondered what the numbers on plastic products mean? The symbol is a part of a coding system developed in 1988 by the Society of the Plastics Industry called the Resin Identification Symbol System (RISS). The numbers tell you what kind of plastic was used to make the product. Here’s a breakdown of what that means in terms of recyclability and toxicity.

Number 1, Polyethylene Terephthalate (PET) or (PETE), is used to make beverage bottles and salad dressing bottles, and carries some risk of leaching phthalates or antimony. #1 plastic bottles are recycled locally.  Other #1 plastics, like those pesky lettuce tubs at the grocery store, contain dyes and additives and are not recyclable locally.

Number 2 – High Density Polyethylene (HDPE), is used in milk jugs, shampoo and detergent bottles, and shopping bags. It carries a low risk of leaching. #2 plastic bottles are recycled locally, and #2 plastic bags can be recycled at the entrance to Broulim’s.

Number 3 – Polyvinyl Chloride (PVC) or (V), is used in cling wrap, shower curtains, rubber duckies, medical equipment, siding, and piping. PVC should never be heated in the microwave or burned. Heating plastic releases endocrine disrupters into food and can cause developmental changes, and burning PVC releases toxins. PVC is rarely recycled.

Number 4 – Low Density Polyethylene (LDPE), is used in bread bags, shopping bags, dry cleaning bags, squeeze bottles, and some carpets and furniture. It has a low risk of leaching, and can be recycled at the entrance to Broulim’s.

Number 5 – Polypropylene (PP), is used for reusable containers (like Tupperware), bottle caps, clothing, and dairy containers. PP has a low risk of leaching and is relatively safe. However, it is not recycled locally due to a lack of markets nearby. Hard-core recyclers can mail their #5 plastics to a company called Preserve through “Gimme 5”. Shipping costs are not reimbursed.

Number 6 – Polystyrene (PS), is used in Styrofoam, meat packaging trays, red plastic Solo cups, and takeout food containers. PS leaches toxins, especially when heated, and is rarely recycled. Reuse foam packaging, and switch to more benign materials.

Number 7 – Other (OTHER). This category represents all plastics that don’t fit into the other categories, many of which did not exist when the RISS system was developed. One type of #7 plastic, polycarbonates, leaches Bisphenal-A and should be avoided. #7 plastics are rarely recycled.

In conclusion, #1 and #2 plastic bottles are recycled locally. #3, #6, and #7 plastics carry a high risk of leaching, are not recycled locally, and should be avoided. NEVER heat plastics in the microwave or burn them.

Many communities ACCEPT other types of plastic, but that doesn’t mean they RECYCLE them. Less valuable plastics are either thrown out or are shipped overseas, where they may or may not be recycled. Teton County’s Recycling Policy stipulates that we will do our best to only collect materials for recycling that we know are actually being recycled. Teton Valley Community Recycling urges you to continue recycling your plastic bottles and bags, and to avoid other types of plastic as much as possible.

Tanya Anderson is the executive director of Teton Valley Community Recycling. For more information, visit tetonrecycling.org.