Trends in microchemical detection methods for illegal adulterants and heavy metals in sports nutrition supplements

Sports nutrition supplements occupy an unstable boundary between food, performance culture, pharmaceutical exposure, and environmental contaminant control. Their matrices include protein powders, creatine products, stimulant pre-workouts, slimming capsules, plant extracts, tablets, functional beverages, and sexual-enhancement products marketed to physically active consumers. This review synthesizes trends in microchemical detection of illegal adulterants and heavy metals in these products, with emphasis on low-sample and low-solvent preparation, rapid screening, confirmatory mass spectrometry, elemental analysis, and multi-contaminant risk interpretation. The evidence base includes athlete supplement-use reviews, market-surveillance studies, targeted and non-target LC-MS/HRMS methods, Raman/SERS and paper-based sensors, ICP-MS/ICP-OES/XRF metal studies, and quantitative risk-assessment papers. Anabolic agents, stimulants, sibutramine, sildenafil analogues, SARMs, prohormones, diuretics, beta2-agonists, glucocorticoids, and 2,4-dinitrophenol are considered together with Pb, Cd, As, Hg, Cr, Ni, Cu, Zn, and other elements. Across the literature, the main trend is not replacement of laboratory confirmation by portable tools, but redistribution of analytical work: field screening, microextraction, and chemometric triage reduce sample and solvent burdens, while LC-MS/MS, HRMS, and ICP-based methods remain decisive for quantification, legal defensibility, and retrospective identification. Regulatory value increases when adulterant and metal data are interpreted jointly because the same product may carry anti-doping risk, acute pharmacological risk, and chronic elemental exposure.