Use of the spectrometric sum parameter for aromatic amines in the monitoring of a former ammunition plant

Aromatic amines are important metabolites of nitroaromatic explosives, henc e monitoring of aromatic amines' content at former ammunition plants is nec essary. Twenty years ago, a threshold limit value of 0.1 mu g/L for the sum of diazotizable aromatic amines in water distributed from the waterworks a t the former ammunition plant in Stadtallendorf/Hesse was established. This value is still measured with a spectrometric sum parameter, in which diazo tization and a subsequent azo coupling of the analytes are utilized. The su m parameter is well suited for the long-term monitoring of filter installat ions, and it allows very quick measurements and a non-target screening of a niline contents, both of which are important in research. Nevertheless, as several problems are associated with this parameter, we developed analytica l methods suitable for the determination of the most important single compo unds contributing to the overall sum. Initial results of these methods show that amphoteric anilines are of considerable importance in ammunition wast e but have been neglected up to now in official monitoring schemes. The sum mation of single compound contents in ammunition wastewater generally gives 3 to 6 times higher values than the spectrometrically determined sum, whic h is mainly due to the choice of the reference substance 4-nitroaniline in the sum parameter.