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The Future is (Bio)Plastic?“There’s a great future in plastics. Think about it.” That wasthe advice whispered in Dustin Hoffman’s ear in the 1967 film“The Graduate.” Fifty years later, the one area of the plasticsindustry whose future still looks bright is bioplastics.According to insiders, the bioplastics industry could be worth$20 billion by 2020. 310 Current worldwide use of bioplasticsamounts to just over one half-million metric tonnes in 2010,which could fill the Empire State Building five times over.While use is expected to rise to 3.2 million metric tonnes by2015, 311 this is still only a sliver of the 200 million tonnes ofplastic resin produced every year 312 (although some analysts saythat it is technically feasible to switch up to 90% of plastics tobio-based feedstocks). 313For the plastics industry going green is as much about themarket opportunity to improve their image as hedging againstrising oil prices. Consumers often assume (and the plasticsindustry would like them to believe) that bioplasticsautomatically meet a gold standard in environmentalprotection, a break from the toxic legacy of vinyl, bisphenol A(BPA) and polystyrene products now filling up the world’slandfills and oceans. Despite attempts to market themselves as‘earthy’ and ‘close to nature,’ bioplastics producers are largelythe same polluting agribusiness and chemical corporations:Cargill and ADM – which sew up most of the world’s graintrade between them – are also two of the biggest players inbioplastics, controlling the Natureworks and Mirel lines,respectively. DuPont, DSM, BASF and Dow Chemical –four of the world’s largest chemical companies – are also keyplayers.Plastic bottles Photo: Shea BazarianDo Bioplastics Biodegrade?Some bioplastics – such as ADM’s Mirel bioplastic and thosemade by Plantic – do break down in the environment or inhome composters, while other bioplastics, even some marketedas compostable, may prove difficult to break down except overa long time. This is particularly true for biobased plastics thatreplicate existing petroleum-derived chemicals. DuPont’sSorona for example makes no claims to break down in theenvironment nor does Braskem’s bio-based Poly VinylChloride (PVC) and Polyethylene. The leading bioplastic,Cargill’s polylactic acid (PLA) sold under the brand‘Natureworks’ is one so-called ‘compostable’ plastic that doesnot break down in home composters, or in the environment,but needs to be hauled away to industrial high-heatcomposters.Nor is it clear how fully the biodegradable bioplastics breakdown. Close studies of so-called degradable plastics haveshown that some only break down to smaller, less visibleplastic particles, which are more easily ingested by animals.Indeed, small plastic fragments of this type may also be betterable to attract and concentrate pollutants such as DDT andPCB. As one plastics industry insider has observed “designingdegradable plastics without ensuring that the degradedfragments are completely assimilated by the microbialpopulations in the disposal infrastructure in a short timeperiod has the potential to harm the environment more that ifit was not made to degrade.” 314Can Bioplastics be Recycled?Theoretically bioplastics can be recycled, but, in reality, thereare few if any recycling facilities that will separate out new biopolymersfrom other plastics. Cargill Natureworks, forexample, insists that PLA can in theory be recycled. In reality,this plastic is likely to be confused with PolyethyleneTerepthalate (PET) used for plastic bottles and so can actuallyhamper recycling efforts by contaminating existing recyclingstreams. In October 2004 a group of recyclers and recyclingadvocates issued a joint call for Natureworks to stop sellingPLA for bottle applications until key questions related torecycling PLA were addressed. In January 2005 the companyput in place a moratorium on selling “additional” PLA forbottle production, but began selling PLA for bottles again,claiming that the levels of PLA in the recycling stream weretoo low to be considered a contaminant. Bioplastics inpackaging in North America are supposed to carry the number7 “chasing arrow symbol,” though industry protocols stipulatethat the symbol must be inconspicuous enough that it doesn’taffect consumers’ buying decisions. 315ETC Group 52 www.etcgroup.org