The new amendment to the Drinking Water Ordinance has been in force since June 2023. In addition to changing the limits of existing parameters, new substances have also been included in the monitoring. For the determination of chlorite and chlorate in drinking water, Metrohm uses ion chromatography (IC) as the most suitable method. ISO 10304-4:2022-03 describes the determination of chlorate, chloride and chlorite in low-polluted water using IC. Using Metrohm's high-performance columns, the limit values of 0.070 mg/L chlorate and 0.20 mg/L chlorite described in the new Drinking Water Ordinance can be determined under the same chromatographic conditions as the other IC parameters required in the Drinking Water Ordinance (fluoride, chloride, nitrite, nitrate and sulfate).
Haloacetic acids (HAA) are usually formed as disinfection by-products during water treatment processes. Some HAA have been classified as potentially carcinogenic. Ion chromatography coupled with mass spectrometry (e.g., single- or triple-quadrupole mass spectrometers) is a powerful technique for addressing many challenging analytical tasks, such as measuring HLW in drinking water samples in the μg/L range.