Compostable 12oz clear cold cups are made from PLA, (polymer made from plants). These disposable cups are great for cold beverages such as iced coffee, iced tea, smoothies, and water. They are suitable for cold liquids, freezer safe. Not microwavable. PLA products should be stored in a cool place below 110° F and out of direct sunlight. These are certified compostable in a commercial facility, which may not exist in your area