Human hair is a biological sample that is, unlike blood, noninvasively collected and can be used in the assessment of element intake. Before analysis, hair samples need to be washed to eliminate external contamination, for which no standard procedure exists. The present study evaluated the efficiency of different processes for washing hair samples (by non-ionic detergent, acids, solvents, and their mixtures), including ultrasonication before ICP-MS element (As, Ca, Cd, Cu, Fe, Hg, Mg, Mn, Mo, Pb, Se, and Zn) analysis. All tested washing procedures using detergent or solvents were satisfactory, while nitric and hydrochloric acid solutions yielded to “released” and lost elements due to damaged hair (visible discolouration and hair impairment). The application of ultrasonication improved washing efficiency up to 10 %, depending on the tested element and washing procedure.; Ljudska kosa je biološki uzorak koji se, za razliku od krvi, skuplja neinvazivno i može rabiti u procjeni unosa elemenata. Prije analize uzorke kose potrebno je oprati kako bi se odstranila vanjska onečišćenja za što ne postoje standardni postupci. Istraživanjem je procijenjena učinkovitost različitih postupaka pranja uzoraka kose (neionskim detergentom, kiselinama, otapalima i njihovim mješavinama) uključujući primjenu ultrazvuka prije analize elemenata (As, Ca, Cd, Cu, Fe, Hg, Mg, Mn, Mo, Pb, Se, and Zn) metodom ICP-MS. Ispitivani postupci pranja bili su zadovoljavajući, izuzev primjenom dušične i klorovodične kiseline, pri čemu se elementi “otpuštaju” i gube zbog oštećivanja kose (vidljive su promjena boje i pucanje vlasi). Primjena ultrazvuka pospješila je učinkovitost pranja uzoraka do 10 % ovisno o ispitivanom elementu i postupku pranja.