Summary report on the developed sample preparation methods for the measurement of SMPs (< 10 μm) and NPs (< 0.1 μm) in complex food matrices: drinking water and milk. The methods will include (i) enrichment prior to analysis, (ii) selective removal of natural background organic/inorganic matter, (iii) size fractionation/isolation, and (iv) homogenisation and partition steps. The accuracy and efficiency of the developed methods will be optimised to demonstrate a negligible effect on the particle characteristics and polymer compositions of samples

This document summarises the development of measurement methods for characterisation of number and mass concentration, size and size distribution as well as chemical identification of nano- and sub-micro-meter plastics in bottled water and milk matrix. This included systematic evaluation of sample preparation strategies including strategies for spiking, enrichment, matrix reduction and fractionation, as well as spike stability in the matrix. Remaining gaps and challenges associated with the detection and characterisation of nano and sub-micro plastics in complex real-world food samples are also discussed here.

“The project 21GRD07 PlasticTrace has received funding from the European Partnership on Metrology, co-financed from the European Union’s Horizon Europe Research and Innovation Programme and by the Participating States.”
• Funder name: European Partnership on Metrology
• Funder ID: 10.13039/100019599
• Grant number: 21GRD07 PlasticTrace