However, a suspicion of co-elution arose, and when another analytical instrument technique (Hydride generation atomic fluorescence spectroscopy (HPLC-HG-AFS)) was applied, concentration of inorganic arsenic was approximately three times lower in a certified reference material, TORT-2.
Aftur á móti kom í ljós, þegar annarri efnagreiningartækni (HPLC-HG-AFS) var beitt á sýni af stöðluðu viðmiðunarefni (certified reference material), að styrkur ólífræns arsens mældist þrisvar sinnum lægri.