Microplastics are small plastic fragments which are hard to see without a microscope. The bigger parts can measure between 1 and 5 millimetres, but the smaller fragments can be up one thousandth of a millimetre.
"Normally, a sieve is being used to detect microplastics", explains Frank Vanhaecke of UGent, "but that makes it hard to find the smallest parts. The method that we are using (ICP mass spectometry, editors' note) was originally developed to measure concentrations of dissolved metals in liquids. However, we have proved that it can also be used to trace the smallest microplastics."
Kristof Tirez of VITO says that the new method allows scientists to map in detail how many microplastics there are in a sample of water: "The number, the size and the dispersal. And the method is very fast: we can measure one thousand parts within a minute."
The method now has to be finetuned to apply it to polluted water, coming from a river, for example. Until now, the Flemish researchers have only tested liquids to which they had added the microplastics themselves.