Mercury concentrations in plaice, flounder and dab from Belgian continental shelf waters (1971-1990)

Results obtained during a survey of 20 years on plaice (Pleuronectes platessa) and 15 years on flounder (Platichthys flesus) and dab (Limanda limanda) are reported. With flounder, two periods could be distinguished. In 1975-1981, higher mercury concentrations (0.38 mg/kg on average) with rather large variations were noted. From 1982 on, concentrations fluctuated around the same mean value (0.23 mg/kg). A gradual decrease of mercury levels in plaice was observed during the twenty years' monitoring period. The mean concentration in 1990 (0.06 mg/kg) was only one third of that of 1971 (0.18 mg/kg... Mehr ...