Routine drinking water analysis

Importance of the Topic

Water quality directly impacts human health and ecosystem stability. Reliable monitoring of anion concentrations in drinking water is essential to comply with regulatory standards and prevent adverse effects from contaminants such as nitrate or sulfate.

Objectives and Study Overview

This study evaluates an economical ion chromatography system (Eco IC) for routine determination of major anions in drinking water. The aim is to verify robustness, sensitivity, and compliance with local and international guidelines using real water samples.

Instrumentation

• Eco IC ion chromatograph with conductivity detector and Metrohm Suppressor Module
• Metrosep A Supp 17 150/4.0 anion separation column
• 863 Compact IC Autosampler for automated injection
• MSM Rotor A suppressor rotor
• Inline ultrafiltration unit for sample pretreatment
• MagIC Net 4.0 Professional software for data acquisition and compliance

Methodology

Drinking water samples were directly injected or filtered inline to remove particulates. Anions were separated isocratically using a sodium carbonate/bicarbonate eluent at ambient temperature. Post-column chemical suppression reduced background conductivity, and a high-performance conductivity detector quantified analytes based on calibration curves ranging from 0.05 to 100 mg/L depending on the ion.

Main Results and Discussion

Calibration showed low detection limits in the low µg/L range. Analysis of Swiss drinking waters revealed chloride (7–23 mg/L), nitrate (7–9 mg/L), and sulfate (5–35 mg/L). Fluoride was detected at 0.05–0.09 mg/L; nitrite, bromide, and phosphate were below quantification limits. Repeatability was within acceptable limits, and all samples met local (TBDV 817.022.11) and EPA standards.

Practical Benefits and Applications

The Eco IC platform offers low capital and running costs, minimal maintenance, and straightforward operation. Its automation capabilities and inline filtration make it suitable for high-throughput labs, water utilities, and academic training.

Future Trends and Opportunities

Further integration of inline sample preparation, coupling with mass spectrometry for broader analyte coverage, and development of remote or portable systems could expand application to environmental surveillance and real-time monitoring.

Conclusion

The Eco IC method demonstrates robust, cost-effective analysis of major anions in drinking water, ensuring regulatory compliance and supporting public health goals.