Formation and determination of organohalogen by-products in water. Part III. Characterization and quantitative approaches

Used as oxidizing biocides, halogen-containing oxidizing agents react with naturally occurring organic matter as well as inorganic compounds, leading to the formation of a wide range of organohalogen by-products (OXBPs). Despite the increase in the number of quantified OXBPs and the improved sensitivity of analytical methods, the mass balance (MB), defined as the percentage of known halides attributed to known, quantified OXBPs divided by the adsorbable organic halide (AOX) values, remains significantly below 100%. As a result, the toxicological and ecotoxicological effects of exposure to OXBPs cannot be assessed precisely. It is crucial to identify new and unknown OXBPs and to increase the scope and sensitivity of the analytical techniques employed. This article aims at providing the reader with a critical overview of the different analytical methods currently employed for OXBP characterization and MB improvement.