Benevo's plastic free, eco-friendly dog poop bags are made from cornstarch and decompose into harmless organic substances after use. EN13432 certified compostable poop bags. Not to be confused with cheaper degradable poo bags which breakdown into billions of tiny plastic particles. Some biodegradable dog poop bags take hundreds of years to biodegrade. EN certified poop bags disintegrate after 12 weeks and completely biodegrade after six months. That means that 90 percent or more of the plastic material will have been converted to CO2. The remaining share is converted into water and biomass.