Researchers at the University of Pittsburgh have found that bioplastics are not the packaging problem solver they were originally considered to be. Instead, the processes required to manufacture them create more greenhouse gases than making them from petroleum.
Made from corn, starch and other renewable resources, bioplastics have long been cited as the solution to the planet's increasing demand for plastic in the face of depleting oil supplies.
However, the researchers analysed the life-cycles of seven petroleum-based polymers (the basis of 'regular' plastic), four biopolymers (bioplastics) and one hybrid, and checked each against standards of biodegradability, wastefulness, toxicity and energy efficiency.
They found that two of the sugar-derived polymers demonstrated signs of eutrophication, which occurs when overfertilised water can no longer support life. Furthermore, biopolymers were worse offenders than petroleum-based polymers for ecotoxicity and carcinogenic emissions.
The researchers also found that combining polymers into a hybrid plastic produced the most harmful results.
This study will cast more doubt over the ecological feasibility of bioplastics, as there have been concerns raised regarding the sustainability of the corn, starch and sugarcane used in their manufacture.
An increasing use of bioplastics by companies keen to 'green' their carbon footprint (Proctor & Gamble, for example, plan to package a range of its leading brands in sugarcane-based plastic from 2011) have led to worries that the use of crops will lead to a depletion of food supplies and drive up prices in developing countries.
Furthermore, waste awareness groups have expressed apprehension at the widespread use and marketing of bioplastics, fearing that consumers may regard them as a 'throwaway' product, thus exacerbating waste and landfill issues – bioplastics are only regarded as an environmentally-friendly packaging solution if composted properly. If they're mistakenly recycled, they are liable to cause problems at recycling facilities.
However, The Green Optimistic reports that while the same theory regarding atmospheric pollutants could be applied to biofuels, the solution doesn't necessarily rely on halting biopolymer production. Instead, we must now seek methods for more efficient and green farming, without the use of harmful fertilisers and chemicals.href="https://earthtimes.org/index.html">Technology News