TON Vanadium

New Thermo Scientific (Finland) automated TON Vanadium 2-reagent system application for Gallery and Aquakem discrete analysers provide an excellent alternative to measure Total Oxidised Nitrogen (TON), a sum of nitrate and nitrite, from water samples. In the TON Vanadium method nitrate is reduced to nitrite by vanadium chloride. The method allows the TON measurement also from sea water or other high salinity matrixes. This offers a significant advantage compared to the commonly used TON method based on hydrazine reduction. Theoretical MDL with Thermo Scientific TON Vanadium application for sea water samples is as low as 0.68 µg/l. The other commonly used method for the determination of TON is reduction of nitrate to nitrite by cadmium. However cadmium being toxic, handling of the cadmium column may pose risks to the users. By using discrete analysis technique and TON Vanadium method, reagent consumption is minimised and cadmium related toxic waste is eliminated. The vanadium chloride method showed excellent correlation to cadmium and hydrazine reductant methods, with all sample types, sea water, natural water and waste waters.