A new survey of recycling facilities across the U.S. has found that many plastic items put into recycling bins are not being recycled.

The survey found that only 15% of 367 recycling recovery facilities accepted plastic clamshells, and only a small percentage took things like plates, cups, bags and trays. None of the facilities could process single-use coffee pods.

Each recyclable plastic container is labeled with a number inside a triangle symbol. That number indicates the type of plastic that product is made from.

Facility operators said there is still recycling demand for bottles and jugs labeled #1 or #2, like plastic water bottles and milk containers. That means producers are still willing to use these types of plastics to make new products.

But demand is almost nonexistent for plastics labelled with numbers 3 to 7, a category known as mixed plastics.

You can read more about the survey here.