Single-use plastic bag alternatives result in higher environmental impacts: Multi-regional analysis in country with uneven waste management

Single-use plastics (SUPs) have been the focus of plastic pollution control, and limiting their use while shifting to other alternatives have been widely promoted in various countries. This study tries to verify the life cycle environmental performances of single-use plastic bag and its alternatives under different scenarios in real world. China is chosen as case study, where provincial variability is prominent in waste disposal, and strictest plastics ban has issued lately in this worldwide biggest market. The study found that HDPE plastic bags have relatively lowest environmental footprints regarding to Acidification Potential, Global Warming Potential, Chemical Oxygen Demand, Eutrophication Potential, Fossil Fuel Depletion Potential and Water Use. Sticking to current waste treatment, large-scale promotion of degradable products will increase environmental impacts by 1.4-22.6 times nationwide. Xinjiang has highest impact of using plastic bag at household level, due to its long-distance transport and high landfill ratio. Henan and Hebei will trigger the most significant changes in Global Warming Potential of 4.6 and 4.4 times if single-use plastic bags are all replaced with other alternatives. Uncertainty and sensitivity test further prove the robustness of results, and extends geographical implications of the findings. These suggest that introduction of new alternatives requires systematic deployment with full life cycle thinking, and SUPs pollution control should be a holistic transformation. Reducing bag weight while ensuring carrying capacity, purchasing local products to shorten transportation distances and shifting towards cleaner energy sources are synergetic ways to reduce the environmental impact of single-use plastic products.