TOC Analysis of Bottled Water Using the Fusion UV/Persulfate TOC Analyzer
Abstract
This application note demonstrates the Teledyne Tekmar Fusion UV/Persulfate analyzer’s ability to measure low levels of TOC in five popular bottled water brands. Bottled water samples varied in source and purification methods including: two natural aquifers, one vapor distilled, one reverse osmosis, and one two-stage microfiltration/UV light disinfection. All results had a 10% window of accuracy, based on a certified check standard concentration, and a precision of 7.0% or less, based on the calculated %RSD of samples and standards run in triplicate.
Introduction
Total Organic Carbon (TOC) is an indirect measurement of water cleanliness and purity, because a variety of contaminants including bacteria, biological matter and foreign material, contain carbon. Five bottled water brands were chosen for TOC analysis using the Fusion UV/Persulfate TOC analyzer. The UV persulfate oxidation technique is well-suited to drinking water analysis because of its reduced carbon background when compared to traditional combustion systems and few interferences, unlike membrane conductivity and color-metric techniques. 1 Designed specifically for drinking water applications, the Fusion has a detection limit of 0.2 ppb and provides intuitive features such as “auto-calibration” which creates a calibration curve from a single stock standard and “intellidilution” which automatically dilutes and reanalyzes samples that exceed the calibration range. Additionally, the Fusion TekLink software is fully 21 CFR 11 compatible and includes a password protected user account management system with permissions; versioned methods, calibrations, schedules, and reports; electronic signatures and other required software functions.