CPCB certified Lab tested by CIPET ISO 17088 100% Compostable carry Bags are made from biodegradable polymers derived from cornstarch. These bags does not contain any form of plastic and are completely compostable. Bags when comes in contact with soil, starts composting and the entire bag is converted to compost in 180 days leaving no trace. This are not even harmful for the environment in any way as tested.