I have been following with interest my colleague Heidi Tolliver-Nigro’s experiments in watching bags rot over at The Inspired Economist, and that got me thinking about biodegradable packaging, especially in the context of this article which recently came across my desk (thanks, Gail!):

Are biopolymers really delivering the eco benefits many claim? Perhaps not, according to a new study by University of Pittsburgh researchers. An article published by news syndicate ANI says the University of Pittsburgh study indicates bioplastics can produce a bigger carbon footprint than petroleum-derived plastics, due [to] farming and energy-intense chemical processing.

Economists and scientists often refer to “unintended consequences,” the subject of an excellent book published in the 1990s called Why Things Bite Back, as well as books such as the so-so The Armchair Economist that point out, among other things, that making cars safer can result in a greater number of fatal crashes. Go figure. It’s a counterintuitive logic that could also be used to explain why, if we stopped using paper or other forestry products, we might actually be dooming those same forests. That is, forests and other natural products that are meant to serve as industrial resources tend to be protected, at least by responsible companies. If those forests lost those protections, they might very well be replaced by strip malls and subdivisions. Anyway, the endeavor to create biodegradable or compostable packaging is certainly a noble one and while I have yet to read the study in its entirety, the lesson to take away from the news brief is that we should ensure that the means to get to a desirable end doesn’t negate any positive impact. (We see the same issue with regard to ethanol—a Scientific American article earlier this year highlighted the debate over whether ethanol production might have a net negative impact on the environment, in essence being no better than the petroleum processing it is meant to replace, at least in part.) I also happened across one of those headlines (from Packaging Digest) that made me go “wha?”:

New biodegradable bag made from CO₂ emissions

Hmmm...interesting idea. My mind was riven with images of cars' tailpipes blowing big bubbles that turned into bags. I doubt that’s what they were talking about. The news brief goes to add:

Melbourne packaging technology company Cardia Bioplastics Limited has developed a what it says is the world first biodegradable plastic bag created from a blend of CO₂ (carbon dioxide) emissions and starch. Chairman Pat Volpe said the company has successfully completed a first production run of the revolutionary carrier bags, known as CO2S – or, carbon dioxide plus a starch based renewable resource.

How does this work?

pollutant CO2 emissions are captured prior to being released into the atmosphere. This pollutant is then transformed into a polypropylene carbonate (PPC) polymer and blended with a renewable resource (starch), using the company’s new technology, to produce the Cardia Bioplastics CO2S™ resin. This product is then used to produce a completely biodegradable carrier bag.

On the surface, it sounds great: find practical uses for stuff we’re trying to get rid of. I’d be curious to know what the practical carbon footprint of this would be, and it’s a product worth keeping tabs on (so to speak) as commercialization draws nearer.