Traces of Inorganic Explosives in the Sewer System - A Review

This review focuses on the presence and the expected concentration of ions related to inorganic explosives in wastewater/sewage. The ionic composition of waste water treatment plant (WWTP) influent has been frequently reported, but has been limited to a few inorganic anions and cations. Identified concentrations of ions in wastewater are 5 - 200 mg/L for major ions, 0.1 - 217 μg/L for heavy metal ions and 0.014 -1.6 mg/L for some also explosive related anions. The discussed methods to monitor wastewater/sewage over an extended period of time look promising, but need to overcome pre-treatment and sampling issues (filtration, dilution) and also the selectivity and sensitivity needs to be improved. The most promising method is based on sequential injection capillary electrophorese coupled with capacitive-coupled contactless conductivity detection (SICE- C4D) and is capable of simultaneous detection of cations and anions with an LOD of 0.005 to 0.061 mg/L, and more importantly portable and automatable. The data provided for this work shows that the levels for the ions of interest cover a broad range, from values under the limit of quantification (