Analysis of Tapwater Contaminants by FTIR and EDX Spectroscopy

Importance of the Topic

Tap water contaminants pose health and maintenance challenges in residential and commercial plumbing systems. Rapid identification of particulate deposits and material fragments is critical for ensuring water quality, diagnosing component degradation, and guiding timely remediation. Combining infrared spectroscopy and electron dispersive X-ray analysis offers a versatile approach for characterizing organic and inorganic constituents of tap water deposits.

Study Objective and Overview

This study demonstrates the application of attenuated total reflection Fourier transform infrared spectroscopy and energy dispersive X-ray spectroscopy to identify unknown contaminants collected from shower head filters. Two types of particulates were examined, with the goals to determine chemical composition, trace the origin of materials, and recommend corrective measures.

Methodology and Instrumentation

• Sampling Protocol Collection of black and white particulates from tap water outlet filters during routine maintenance.
• FTIR Analysis A single-reflection ATR unit was used to acquire mid infrared spectra, which were matched to a reference library of known tap water contaminants.
• EDX Analysis Qualitative and quantitative elemental mapping was performed under vacuum conditions, with spectra collected at 15 kV and 50 kV acceleration voltages.

Used Instrumentation

• FTIR System IRAffinity-1S with MIRacle10 germanium prism ATR accessory Resolution 4 cm⁻¹, 40 scans, Happ-Genzel apodization, DLATGS detector
• EDX Detector EDX-8000, Rhodium target X-ray tube, vacuum atmosphere, beam diameters of 1 mm and 3 mm, integration time 100 s per channel, polypropylene support film

Key Results and Discussion

• Contaminant A The dark fragment was identified by FTIR as ethylene propylene diene rubber containing talc and kaolin additives. EDX confirmed major elements including carbon from the polymer, silicon and aluminum from fillers, chlorine from residual disinfectants, and trace metals such as copper and zinc from corroded components.
• Contaminant B A white particle matched a vinyl chloride-vinyl acetate copolymer in the FTIR library. EDX analysis revealed dominant carbon and chlorine, with minor contributions of metal ions consistent with degraded seal materials.
• Source Attribution Physical comparison and spectroscopic library matching traced Contaminant A to a rubber gasket within the shower assembly, while Contaminant B likely originated from aged sealant in water supply connections.

Benefits and Practical Applications

This dual-style analysis allows rapid pinpointing of contaminant chemistry and origin without extensive sample preparation. It supports maintenance decision making in plumbing systems, enhances water quality diagnostics, and helps manufacturers improve material selection for durability.

Future Trends and Potential Uses

• Integration of hyperspectral imaging with ATR accessories for spatially resolved contamination maps
• Development of real-time in situ ATR probes for continuous monitoring at critical water outlets
• Advances in low vacuum or environmental EDX to analyze hydrated samples without dehydration artifacts
• Machine learning driven spectral libraries to automate contaminant classification in water systems

Conclusion

Combining FTIR ATR spectroscopy with EDX analysis offers a powerful workflow for identifying and tracing the origin of tap water particulates. The approach delivers both organic material identification and elemental fingerprinting, enabling effective maintenance strategies and quality control in plumbing infrastructure.

References

• Shimadzu Application News No. X255