Danish study finds plastic bags have lowest environmental impact

When you take into account the science as well as the manufacturing processes involved, plastics tend to have a lower overall impact on the environment than other materials. That is what the Danish Environmental Protection Agency discovered and published in a study that analyzes the environmental impact of the production, use and disposal of grocery carrier bags currently available at Danish supermarkets.

Seven materials—low-density polyethylene (LDPE), polypropylene (PP), recycled polyethylene terephthalate (rPET), polyester, biopolymer, paper, cotton and composite—and their variations were analyzed in terms of their environmental impact in compliance with international standards ISO 14040 and ISO 14044. Different end-of-life options were taken into consideration, including incineration, recycling and reuse as a waste bin bag before incineration. For all carrier bag alternatives, the assessment took into account the impact of the place of production of the bag and its packaging (assumed to occur in Europe), transportation to Denmark, use and disposal, which could occur in Denmark or within Europe.

With regard to production and disposal, the study found that lightweight LDPE carrier bags provide the overall lowest environmental impact according to most environmental indicators, when not considering reuse. In particular, between the types of available bags, LDPE carrier bags with a rigid handle are preferred. Effects of littering for this type of bag were considered negligible for Denmark, the report concluded.

The study also stated that “reusing the carrier bag as a waste bin bag is better than simply throwing away the bag in the residual waste, and it is better than recycling. Recycling can potentially offer benefits in the case of heavy plastic bags, such as PP, PET and polyester. Reuse as a waste bin bag is most beneficial for light carrier bags, such as LDPE, paper and biopolymer.”

EuPF, the EU-level trade association based in Brussels representing European Plastics Converters, welcomed the analysis.

Click here to read the full report.