Nitrate ion is derived from protein etc. as a result of the decomposition by germs and bacteria and therefore, it isconsidered as an effective index to show human-induced contamination.The water quality standard value for nitratenitrogen is 10 mg/L or less. in general, about 0.1-1 mg/L of nitrate ion is contained in fresh water. This time, nitrate ionin mineral water was assayed by using the water quality analysis reagent kit for nitric acid (nitrate nitrogen) of KyorituChemical-check Lab. This reagent kit allows the analysis of nitric acid in fresh water in the absence of nitrous acid. U5100, when used with the reagent kit for nitric acid, allows easy analysis of nitric acid. Because of the automatic 6-cellturret, which is included in the standard installation, the sample switching can also be perfomed smoothly.
