Many people don't know how to recycle milk cartons, as evidenced by this photo of three milk cartons erroneously placed in the paper bin at my office.
Here's the truth, taken straight from the Carton Council (the main organization for carton manufacturers in the US):
Cartons are made primarily of paper but also have a thin layer of polyethylene, or plastic. Shelf-stable cartons contain a layer of aluminum. As such, milk cartons should be recycled with plastic, metal, and glass containers. Ultimately, the cartons will be sorted separately at the recycling facility and disposed of properly.
This story is available exclusively to Business Insider subscribers. Become an Insider and start reading now. Have an account? Log in.(The New York City Department of Sanitation gives the same instructions.)
A few other surprising facts to keep in mind:
You don't need to rinse out cartons before recycling. (Of course, you may want to if worried about smells.)
You also should not flatten the carton. Sorters at recycling facilities will have an easier time identifying the object if it's in its standard form.

Watch: Every difference between UK and US Five Guys including portion sizes, calories, and exclusive items
ncG1vNJzZmivp6x7o8HSoqWeq6Oeu7S1w56pZ5ufonypu9Zmq6hlopqwuq%2FLoqWgZZ2euax5wpqpraeeqHpzfJBwZGs%3D