When the plastics industry promotes and widely circulates false and misleading claims about the environmental impact of paper bags in Canada, we have an obligation to defend ourselves, and to ensure that Canadians get all the facts.
What we find particularly offensive is the public parade of various European "life cycle" studies in support of the claim that paper bags are as bad or worse for the environment than plastic ones. None of these studies, in fact, reflect the realities of Canadian paper bag production. They are old, of varying quality and relevance, and not one of them includes Canadian data on how bags are actually made in this country.
1. The data is old.
Accurate data is critical to life cycle conclusions. The respected not-for-profit Institute for Environmental Research and Education (IERE) says all primary data (data gathered directly from actual bag-making operations, for example) "shall be no more than three years old." Secondary data (gathered from publications in the peer reviewed literature or grey literature such as government publications) "must be no more than 10 years old, unless it can be verified by an industry expert to be unchanged."
When we look at the European studies that the Canadian plastics industry loves to quote, however, and which is splashes all over its bag-specific website, we see every single one of them includes data that is over ten years old. The UK Environment Agency report (Date requirements and data quality 3.5 and Annex C Description of Inventory Data) was published in 2011 for the data year 2006, but in fact uses life cycle inventory data that stretches back to 1999 (17 years); and, the Scottish Report adjusts data from an earlier French study (Carrefour) whose data was "taken largely from the mid to late 1990s."
That's over 20 years ago. Around the time of the Million Man March in Washington DC or the murder trial of OJ Simpson, Jack Nicklaus winning the British Open, or former US vice president Al Gore helping push the Internet from academia into schools for the first time.
2. The studies vary in quality and relevance.
If you are going to quote life cycle assessments (LCAs) then at least quote the ones that are current (not old, as noted above) and ones that meet internationally acceptable standards for comparative analysis (ISO 14020, ISO 14021, ISO 14025, ISO 14040, ISO 14044, and ISO 14050).
Only two of the European studies cited were original LCAs. And both have problem areas which the authors and/or other life cycle practitioners have acknowledged. The Carrefour study was specific to France and how that country made and imported bags using data back in the 1990s, its relative treatment of greenhouse gas emissions at end-of-life has been questioned, and it used a different functional (measuring) unit that the other, later studies.
The UK study acknowledged that most plastic carrier bags were imported from Asia, but because no Chinese data-sets were identified, it modified average numbers supplied by the European plastics industry instead. Its Final Review statement also agreed that no clear comparison had been established based on the functional unit (thus not meeting a key ISO requirement).
And the Scottish Report, which the plastics industry says has, "some of the most credible data," was neither an original LCA nor peer reviewed, and acknowledged that its findings "cannot be used for a precise quantification of environmental impacts. This would require a full cycle analysis based on the Scottish situation, which is outside the scope of this study."
And here's the clincher!
3. There is no Canadian data in these studies.
We learn from these studies something about French, Spanish, Italian, Turkish, Malaysian, and Chinese bags but nothing about Canadian bags. We learn about France's energy grid (highly unclear) and China's energy grid (78% coal-burning at the time of one of the studies), but nothing about Canada's energy grid, which is quite different. And this is crucial because energy consumption is the major environmental impact category for every type of bag.
Life cycle experts like IERE say, "wherever possible, the electric grid data should represent the electricity purchased or generated by the local entity." If that data is not available, you move to aggregated regional or national data.
So, until Canadian energy data is used, as just one example, these studies have little relevance to Canada. The Canadian plastic industry tacitly acknowledges this when it rushes to point out that most Canadian plastic bags are not made from dirty coal or crude oil from China but rather from fossil fuel extraction in Alberta. But for some reason it doesn't extend the same Canadian-specific rights to the Canadian paper bag industry for its high used of leftover sawmill residues and renewable, carbon-neutral biomass.
It's not as if we haven't told them this before, numerous times. We have. Maybe, just maybe, incorporating this science and these facts into their public messaging to Canadians would seriously impact their preferred story line of paper bags being worse than plastic.
Hopefully, for its own credibility if nothing else, the plastics industry will to the honourable thing and delete these old and irrelevant-to-Canada studies from its website. And while it's at it, maybe, just maybe, it will cover off one key factor that these studies and its bags website don't address: the impact of bag litter on marine life, a growing environmental concern.
John Mullinder, executive director, PPEC, contributes regular posts on environmental and sustainability issues impacting the Canadian paper packaging industry.