Informing policy on grocery carrier bags: Evidence from a life cycle sustainability assessment

Abstract

The environmental impacts of plastic waste have received significant attention from both policy makers and the general public. A number of countries have banned certain single-use plastic products, including plastic carrier bags. However, alternatives to plastic carrier bags come with their own set of impacts. The economic, social and environmental impacts associated with plastic bags should be assessed alongside those of the various alternatives, across their respective life cycles. This paper presents results from a Life Cycle Sustainability Assessment of 16 different grocery carrier bag options in South Africa. The aim was to compare the bags in terms of environmental and socio-economic performance, and to inform policymakers, retailers and the general public about which type of bag is “best” in the South African context. Environmental indicators were based primarily on the ReCiPe 2016 impact assessment methodology. However, current life cycle assessment methodologies exclude indicators relating to the impacts of plastic pollution. We therefore developed a new indicator, namely persistence of plastic material in the environment, as a proxy for impacts associated with plastic pollution. We also added two key socio-economic indicators; namely employment and affordability. Overall, reusable plastic bags (particularly the 70 µm HDPE bag) perform better than singleuse bags, assuming that they are reused at least 3 to 10 times. The best performing singleuse bag is the common 24 µm HDPE bag with 100% recycled content. Biodegradable bags perform poorly overall, except on the plastic pollution indicator. Single-use bags perform best in terms of employment, particularly paper bags.