Analytical monitoring of trinitrotoluene metabolites in urine by GC-MS. Part I. Semiquantitative determination of 4-amino-2,6-dinitrotoluene in human urine.

A routine procedure for the monitoring of occupational exposure to 2,4,6-trinitrotoluene (TNT) based on the semiquantitative determination of 4-amino-2,6-dinitrotoluene (4A2,6-DNT) in urine samples by gas chromatography (GC-MS) was developed. For calibration purposes, a standard sample of 4-amino-4,6-dinitrotoluene was prepared. Urine samples were collected from munition workers in a military plant in Hradec Kralove district. The samples were extracted into ethyl acetate, and analyzed by GC-MS without previous derivatization. The GC was equipped with a DB1701 column (30 m, 0.25 mm, 0.25 microm) for optimum separation. 4A2,6-DNT was detected at concentrations above the limit of quantitation (0.2 mg/L). This simple method is sufficient for the screening of high degree of TNT exposure and constitutes the first step of a broad project focused on this occupational medicine problem.