This dataset contains the results of chemical analyses of water, sediment, and marine bivalves (Mytilus spp.) for residues of submerged munitions, which were taken during various field excursions to three wrecks from the First and Second World Wars in the North Sea: KW58 (Belgium), SMS Mainz (Germany), and UC30. Water and sediments were collected using CTD rosette water samplers and Van Veen sediment grabs (SMS Mainz), or by divers (KW58 and UC30). The mussels for mussel monitoring were collected near the island of Sylt (Germany) and exposed in cages on the wrecks for several weeks. Samples were frozen immediately on board and transferred to the lab for examination. All samples were analyzed for the explosive 2,4,6-trinitrotoluene (TNT) and its two primary metabolites, 4-amino-2,6-dinitrotoluene and 2-amino-4,6-dinitrotoluene, using gas chromatography tandem quadrupole mass spectrometry (GC-MS/MS).