Microplastics and nanoplastics do not yet pose a widespread risk to humans or the environment, except in small pockets. But that evidence is limited and the situation could change if pollution continues at the current rate. This is the verdict of a group of experts chaired by professor Bert Koelmans from Water and Sediment Quality at WUR, in an Evidence Review Report published today by SAPEA. Their report will inform the forthcoming Scientific Opinion from the European Commission’s Group of Chief Scientific Advisors, due in 2019. The Opinion in turn will be delivered directly to European Commissioners to help inform policy-making.
The SAPEA report’s authors draw on a comprehensive examination of the best available evidence from the natural sciences and computer modelling, as well as social, political and behavioural sciences. They highlight that microplastics – tiny particles under 5mm in length – are already present across air, soil and sediment, freshwaters, seas and oceans, plants and animals, and in several components of the human diet. These particles come from a variety of sources, including plastic products, textiles, fisheries, agriculture, industry and general waste.
The report also notes that, in controlled experiments, high concentrations of these particles have been shown to cause physical harm to the environment and living creatures, including inducing inflammation and stress. However, the authors point out that concentration levels measured in the real world are well below this threshold – though there are also limitations in the measurement methods currently available.
Professor Bart Koelmans, chair of the SAPEA working group that wrote the report, said: “The evidence about nano- and microplastics remains uncertain, and it is by its nature complex, but so far there is no good reason to think they pose widespread risks to humans or the environment. Of course, a lack of evidence for risk doesn’t mean we should assume that there is no risk. But one thing is for certain: concentrations of microplastics in the environment are increasing. If we keep polluting at the current rate, we will have a real problem in the future.”