According to the U.S. Department of Agriculture, Americans buy 6 billion gallons of milk a year. Each person consumes about 20 gallons; if you have young children in the house, chances are good that number is higher. No matter where you live, your milk should come packaged in one of three ways: paper cartons, plastic jugs or glass jars, all of which are highly recyclable. Most curbside programs will accept all types of milk containers (though if you buy milk in glass jars, you might plan to return them to the bottler for reuse). If they do not, there are other resources to ensure milk cartons stay out of your local landfill or incinerator.
What are milk cartons made of?The Carton Council, a trade association for the carton industry, reports that paper milk cartons are made of paperboard covered with a thin layer of food-safe polyethylene plastic (also known as PET or PETE or by the recycling number 1) on both sides of the paper. Shelf-stable milk cartons (those that do not require refrigeration until the seal has been broken) also have a thin layer of aluminum foil on the inside of the package. Other items that come in similar cartons include juice, egg substitutes and non-dairy milk (such as soy or almond milk). Milk also comes in #2 plastic containers, which are made of high-density polyethylene, or HDPE. Glass milk bottles are comprised of clear glass. Glass bottles were the only way to package milk in the 19th century. Milkmen delivered them to people’s doors daily, since there was no refrigeration and milk had to be consumed the same day. The paper milk carton was invented in the early 20th century, but took a long time to gain acceptance, since they could not be reused or sanitized. Plastic milk jugs made their first appearance in the 1960s.
How do milk cartons get recycled?Paper milk cartons can be separated from other types of paper and sent to paper mills, which turn them into new products. Plastic milk cartons can be melted down along with other #2 containers and turned back into new products as well. Besides bottles, #2 plastic can be used for floor tiles, lumber, even recycling bins. Glass bottles can be combined with other used glass, melted down and recast into new glass containers.
How to recycle milk cartonsMany curbside programs will accept milk cartons (both the paper and plastic kind). Check with your local provider to make sure, but since almost all curbside programs accept paper and #2 plastic, milk cartons are good candidates for your curbside bin or cart. Be sure to rinse them well and let them drain. This will cut down on sour milk odors in your recycling bin and the amount of smelly liquid that comes in contact with staff at the recycling facility. There are a couple questions about milk cartons you might ask your curbside pick-up provider:
- Whether the lids should be left on or off. In the past, the answer was always “no,” but recycling technology has changed and many municipalities want the caps on paper and plastic containers to stay in place. San Diego and Austin, TX, both request that caps be left on, while Ann Arbor, MI, and Canton, OH, want homeowners to remove the caps before placing them in the bin.
- Whether you should tear out the plastic spout in the milk carton. In some cities, such as Brattleboro, VT, the answer is yes, but this request is rare. Paper mills often have a screen to remove contaminants during the recycling process, and the plastic pieces will get caught in it.