The adult cestodes Monobothrium wageneri and Bothriocephalus scorpii from the intestines of their respective final hosts, tench (Tinca tinca) caught in the river Ruhr, Germany, and turbot (Scophthalmus maximus) collected from two sampling sites on the coast of Gdansk, Poland, were analyzed for lead and cadmium by atomic absorption spectrometry. Both cestode species contained significantly higher cadmium contents than did the muscle, liver, and intestine of their fish hosts. Whereas M. wageneri also contained several times more lead than did the organs of tench, B. scorpii showed nearly the same lead burden as did the liver and intestine of turbot. Posterior sections of B. scorpii comprising gravid proglottids contained significantly higher concentrations of lead and cadmium than did the anterior proglottids.