World Centric compostable cold cups are made from NatureWorks Ingeo™, which is derived from plants grown in the USA. Cups meet the most stringent scientific requirements for biodegradability and compostability, and are ASTM D6400-99 certified for "compostable plastics." Cups are as light and strong as plastic, but fully biodegrade when composted. Best used for beverages below 110°F. Must be stored below 110°F and away from heat, hot surfaces and direct sunlight.