TY - JOUR A1 - Altmann, Korinna A1 - Portela, Raquel A1 - Barbero, Francesco A1 - Breuninger, Esther A1 - Camassa, Laura Maria Azzurra A1 - Velickovic, Tanja Cirkovic A1 - Charitidis, Costas A1 - Costa, Anna A1 - Fadda, Marta A1 - Fengler, Petra A1 - Fenoglio, Ivana A1 - Giovannozzi, Andrea M. A1 - Haugen, Øyvind Pernell A1 - Kainourgios, Panagiotis A1 - von der Kammer, Frank A1 - Kirchner, Markus J. A1 - Lomax-Vogt, Madeleine A1 - Lujic, Tamara A1 - Milczewski, Frank A1 - Moussawi, Mhamad Aly A1 - Ortelli, Simona A1 - Parac-Vogt, Tatjana N. A1 - Potthoff, Annegret A1 - Reinosa, Julian J. A1 - Röschter, Sophie A1 - Sacco, Alessio A1 - Wimmer, Lukas A1 - Zanoni, Ilaria A1 - Dailey, Lea Ann T1 - Characterizing nanoplastic suspensions of increasing complexity: Inter-laboratory comparison of size measurements using dynamic light scattering N2 - Understanding the potential human health risks associated with micro- and nanoplastic exposure is currently a priority research area. Nanoplastic toxicity studies are complicated by the lack of available, well-characterized test and reference materials. Further, many nanoplastic test materials are inherently more polydisperse and heterogenous in shape compared to polystyrene beads, making accurate and representative size distribution measurements particularly challenging. The aim of this study was to conduct an inter-laboratory comparison of dynamic light scattering measurements, the most commonly used particle sizing method for nanomaterials. Using a published standard operating procedure, size measurements in water and a standardized cell culture medium (CCM) were generated for spherical, carboxy-functionalized polystyrene nanoparticles (PS-COOH; 50 nm; benchmark material), and for increasingly complex in-house produced spherical poly(ethylene terephthalate) (nanoPET) and irregular shaped polypropylene (nanoPP) test materials. The weighted mean of hydrodynamic diameters of PS-COOH dispersed in water (55 ± 5 nm) showed moderate variation between labs (coefficient of variation, CV = 8.2%) and were similar to literature reports. Measurements of nanoPET (82 ± 6 nm) and nanoPP (182 ± 12 nm) in water exhibited similar CV values (nanoPET: 7.3% and nanoPP; 6.8%). Dispersion of PS-COOH and nanoPET in CCM increased the CV to 15.1 and 14.2%, respectively, which is lower than literature reports (CV = 30%). We conclude with a series of practical recommendations for robust size measurements of nanoplastics in both water and complex media highlighting that strict adherence to a standard operating procedure is required to prevent particle agglomeration in CCM KW - Nanoplastics KW - Reference materials KW - Polypropylene PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-644571 DO - https://doi.org/10.1039/d5en00645g SN - 2051-8153 SP - 1 EP - 15 PB - Royal Society of Chemistry (RSC) CY - Cambridge AN - OPUS4-64457 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -