Microplastics are environmentalism's hottest topic, with brands and governments pledging to combat the problem. But what is the plastics industry itself doing to address the issue?
Speaking today at SEPAWA Congress, PlasticsEurope representative Dr Christian Block called for a clearer definition 'microplastic', as well as strategies to combat the plastic litter that ultimately results in ocean microplastic pollution.
Microplastics refer to polymers – including thermoplastics, thermosets, elastomers and water-soluble or dispersible polymers – that are less than 5mm in diameter.
Block explained that there are two types of microplastic: primary – intentionally added to a product or the result of product usage; and secondary – the result of decomposition of macroplastics over time via oxidation, etc.
Perhaps surprisingly, in a 2018 study of emissions per gram per capita of Germans, the biggest source of microplastics by a long way was via the attrition of car tyres while driving.
Cosmetics was much further down the list, with the European cosmetics industry having reduced its microplastic usage by 97% by May 2018.
Macroplastic-derived microplastics accounted for just 25% of microplastic emissions in Germany, but Block noted that the ratio of primary to secondary microplastics would be different, for example, in Asia.
Representing his industry, Block stressed the need for a low-end cut-off point for microplastics size. The European Commission defines microplastics as anything below 5mm, but Block believes this should be from 5mm-1µm, "otherwise this opens the door to all polymers used to formulate soap and detergents", he said; these would include widely-used opacifiers, film-formers and bulking agents.
He applauded that the impact of microplastics on the environment was a growing area of research, but he called for more sound, robust scientific studies on the topic, rather than anecdotal ones.
One way the industry was trying to tackle the issue, he added, was through Operation Cleansweep, which addresses unintentional supply chain losses of plastic pellets when shipping from plastics manufacturers to converters. By the end of 2018, PlasticsEurope anticipates all its members will have signed up to the pledge.
Concluding, Block addressed the need for significant investment in waste management in growing global economies, to reduce the amount of plastic ending up as litter... and ultimately in our oceans as microbeads.