Bioplastics – are they for real?

I had an interesting meeting earlier today. I was invited to meet with Zhaotan Xiao, the President of the Singapore-based Asia-Pacific office of RWDC Industries. RWDC Industries have been in the news in Singapore of late through their development of a polyhydroxyalkanoates (PHA)-based drinking straw, which is being suggested as a commercially-viable alternative to conventional plastic straws. PHAs are polyesters, a type of hydrocarbon, that are produced by several types of microorganisms, such as the bacterium Cupriavidus necator, through fermentation of vegetable-derived oils and sugars. They can be mixed with other compounds (e.g. calcium carbonate) to form single-use plastic-like substances that unlike plastics from petrochemicals are biodegradable over relatively short timescales. In fact at today’s meeting we were told that a drinking straw made from PHA would completely biodegrade once released to the environment in as few as 12 weeks. Aside from straws, Zhaotan also showed us PHA-derived, bioplastic-backed paper ~ the kind of material that in its petrochemical-derived form is extensively used, including in the manufacture of disposable coffee cups. According to Zhaotan the PHA-derived bioplastic commodities we were shown have the potential to be produced at scale and at a cost that makes them commercially viable.

All sounds great. Should we be wowed? Has RWDC found the answer to the global problem of single-use plastic pollution? Even if everyday disposable commodities can be made at low cost from biodegradable plastic, is that really the answer? Waste is still waste, surely, even if it does biodegrade? What about the energy that has been used to produce a commodity that is simply thrown away after a single use, or at best a relatively few uses? What about all the embedded pollution in producing single use items, especially given that all plastic items, even those made from biodegradable bioplastics, contain additives, to make the plastic more malleable, more heat-resistant, less combustible etc – and those additives (e.g. Biosphenol A, or BPA) may be even more harmful than the plastic?

The development and use of PHA is an example of Green Chemistry in operation. No doubt Green Chemistry, or the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances, has some of the answers to questions regarding environmental pollution. Green Chemistry – or at least the promise of finding environmentally friendly ways of maintaining or even allowing an increase in consumerism – runs the risk of moral hazard, however. What if none of these proposed solutions actually work, while the prospect of them actually working has persuaded us that we don’t need to change our behaviour to make fewer demands on our environment? What happens then?

PHA is not a new discovery, as Zhaotan was happy to acknowledge at today’s meeting. I hope that RWDC goes on to fulfill all its early promise. If it doesn’t, however, it will not be the first producer of bioplastics to run into trouble because it promised more than it could deliver ….. Only a couple of months ago, shares were suspended in the Italy-based Bio-On company, which produces “environmentally-friendly bioplastics” including a PHA-based replacement for plastic microbeads used in cosmetics etc, having been accused on the Reuters website of being “a massive bubble based on flawed technology and fictitious sales”! Hopefully bioplastics will provide a real alternative to petrochemical-based plastics, but don’t let that distract us from the real source of the global plastic pollution problem ~ our extremely wasteful use of the world’s resources, however quickly the commodities they are used to produce eventually degrade.

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