Chicago’s new restriction on plastic bag use aims to reduce plastic litter, but it could also propagate the belief that paper bags are greener than plastic ones. Life cycle analysis of paper vs. plastic reveals that both options have environmental drawbacks. Some experts note the best answer to the supermarket “paper or plastic” question is - “neither.” “The science shows that moving from plastic to paper is not necessarily ‘greener,’” says Northwestern University’s Eric Masanet. Instead, it just shifts the environmental impact from decreasing litter to increasing resource use and greenhouse gas emissions. Masanet joins Kate Sackman from EcoMyths Alliance to make the comparisons. (Flickr: Beth/The Pittsburgh Tote Bag Project)