From an ecological point of view, is it better to choose a glass or a plastic container? Is recycled glass better for the environment than recycled plastic? Are plant-based polymers really greener? Actually, the answers that the average consumer can get to these questions are sometimes far-fetched. "Comparisons on packaging alone are too often based on a limited number of criteria (one or two),” regrets the French Packaging Council. Under such conditions, claiming that some packaging types would be more virtuous than others does not make sense. For the French Packaging Council, only comparisons that take into account all environmental impacts are likely to provide true information.

Life-cycle assessment

According to the Council only environmental impacts assessments conducted with complete life-cycle assessment (LCA) are likely to provide “accurate, objective and thorough environmental information,” as required by French law n°2009-967 of August 3rd 2009, called Grenelle I.

These assessments are based on standardized tools (ISO 14040 and 14044) and must be: multi-step (i.e. concerning the entire lifecycle of the product, from extracting raw materials and generating resources to final elimination, without leaving out production stages and utilization) and multi-criteria (i.e. taking into consideration a sufficient number of environmental impacts).

As far as packaging is concerned, the most generally investigated environmental impacts are are: climate change (greenhouse gases emissions, including CO2), water eutrophication, aquatic eco-toxicity, the exhaustion of non-renewable natural resources, non-renewable energy consumption, water consumption, air acidification, loss of biodiversity, production of non-recovered waste (ultimate waste). “The most common tools for carrying out thorough LCAs use six criteria on average (with a minimum of four),” the Council adds.

However, the French Packaging Council reminds that, despite their interest, LCA calculations very often give results with 10-15% margins of error. “That means that any differences that are smaller than this margin are by definition relatively insignificant.”

Low relative share

Furthermore, packaging often account for a small fraction of the problem and their environmental impact cannot be assessed independently from its use by the final consumer. According to the Council, the relative share of packaging in the various environmental impacts is usually low (approximately 10% for food).

“So general conclusions on the packed product should be avoided when packaging has much less of an impact than its contents.”

Fair information

Thus, according to the French Packaging Council, the comparison between packs made from different materials, is fair, objective and complete information only where:

- the two packaging deliver the same value in use to the consumer/user (same features and usage characteristics) for the packed product.

- a full multi-criteria LCA was conducted,

- all examined impacts vary significantly in the same way (beyond error margins).

A clarification that was definitely needed in a context where consumers express high concerns towards environmental issues but low confidence towards industry claims.