Paper or Plastic? A Comparison of the Carbon Emissions of Grocery Bags

Paper and plastic grocery bags, as well as reusable bags (non-woven polypropylene), all can be used to carry out purchases from the store. While these different bag types serve essentially the same function, how do their environmental impacts differ? One way to measure environmental impact is by examining a bag’s entire life cycle. A product’s life cycle encompasses various stages starting with the extraction of raw materials, going through production and then use, and ending with a waste management option (e.g. landfill or recycling). Life cycle assessment is a tool to evaluate one or more impact areas of a product over its entire life cycle. In this comparison, carbon emissions are the measure of environmental impact. Several scholarly articles about life cycle assessments of plastic, paper, and reusable bags were reviewed and their findings compared. The results of this research indicate that if all bag types were used only once, then a plastic bag would have the lowest carbon emissions. However, if paper bags were reused four times and reusable bags were used at least eleven times, then they could achieve lower carbon emissions than a plastic bag. Measuring environmental impact is complicated, and looking at carbon emissions to calculate environmental impact only highlights one problem area related to effects on the environment. Looking at other impact areas, such as water pollution, might yield different results regarding which bag type has less environmental impact.