Researchers from Vrije Universiteit Amsterdam recently published a Nature Medicine review on micro- and nanoplastics (MNPs) in humans, arguing that rigorous analytical practice is essential for credible exposure and health assessments. Their message starts well before the instrument: sampling must be plastic-free, with field and procedural blanks, clean-air handling, and transparent reporting of containers and transfers. Too often, these basics are applied inconsistently, limiting comparability and confidence. Sample digestion then has to remove the biological matrix without altering the polymers. Hot nitric acid can damage plastics or coagulate blood; strong alkali may depolymerize PET; enzymes are gentler but selective and costly. Even foaming oxidants can drive particles onto vessel walls and decrease recoveries. Systematic validation, with negative and positive controls, plus tracking of blanks and recoveries, is essential. On instrumentation, Py-GC-MS offers mass quantification, but lipid co-pyrolysis can mimic polymer markers (e.g., alkenes for PE), demanding rigorous cleanup, polymer-specific markers, and support from more advanced methods such as high-resolution mass spectrometry and multivariate calibration. Spectroscopic methods, meanwhile, count and size particles yet miss much of the nano-range, whereas mass methods quantify load but not particle metrics. The authors call for harmonized, dual-modality workflows that co-report mass and particle data, anchored in consistent QA/QC across labs.