Small quantities of degradable plastic films as low as 2 percent can cause "significant, detrimental impacts" to the quality of plastics recyclates, according to a new peer-reviewed industry study.
The findings of the study, commissioned by European Plastics Converters (EuPC), the Brussels-based trade body, are likely to reignite the debate surrounding the presence of bio-degradable plastics in the recycling stream.
EuPC said it had commissioned independent industrial tests which had been conducted by Wolfgang Stadlbauer of the Transfer Centre for Polymer Technology in Austria.
Tests focused on four different mixtures of degradable plastic bags and one virgin LDPE recycling material and were conducted during a six month period, during which more than 9.45 tonnes of plastic carrier bags were processed and more than 3,700 measurements were taken, EuPc said.
"Although all the materials could be processed, the results show that even in quantities as low as 2 percent, degradable plastic films cause significant, detrimental impacts to the quality of plastic recyclates.
"These impacts are not only detrimental in terms of mechanical properties of the recycled material, but also involve visual impacts on the newly produced film," EuPc said in a statement.
The Brussels organization has subsequently called on legislators and waste management authorities across the European Union to push for increased separation and collection of degradable plastics.
Alexander Dangis, EuPc's managing director, said: "Over the past years, there has been considerable concern in Europe surrounding the effects of bio-degradable plastics on recycling streams.
"These test results now prove that separate collection of degradable plastic products is needed in Europe if we want to further develop recycling streams and work towards a circular economy."