Janusz Guziur

Nickel in the muscle tissues of freshwater fish from north eastern Poland should not cause human health concerns

Excessive intake of nickel (Ni) is known to produce adverse health effects in humans, including carcinogenicity and allergenicity. The main route of exposure for humans is diet, including fish. There is, however, little information concerning Ni content in freshwater fish in Poland. The aim of the study was to determine the concentrations of Ni in meat tissues of three fish species from north eastern Poland and assess toxic potential to healthy and susceptible sub-groups of individuals. The settings for the study lakes span a range of anthropogenic influence from protected areas to a basin with a town and several villages and another one influenced by a pesticide tomb leakage. Fish were netted and kept frozen until analysis. After defrosting, the fish were filleted and minced. The ashed samples were dissolved in nitric acid and analyzed for Ni by flame atomic absorption spectrometry. Roach meat contained 6.6–23 µg kg−1 Ni, bream 9.5–178 µg kg−1, and carp 16.5–139 µg kg−1. These concentrations are low, indicating that the fish were not excessively contaminated with the metal. Consuming a 250 g portion of fish would result in an average nickel intake of 4 µg for roach, <10 µg for bream, and <20 µg for carp. These values represent only 0.4–2% of the maximum level that is likely to pose a risk of adverse effects as established in the USA. Consumption of fish from the study region need not necessarily pose a health threat.

Lead and cadmium content in the meat tissues of fish from water ecosystems in the vicinity of a pesticide tomb

Lead and cadmium content in the meat tissues of fish from water ecosystems in the vicinity of a pesticide tomb Lead and cadmium levels were determined in the meat tissues of roach, bream, and carp netted in a lake and in fish ponds threatened by a pesticide tomb and in control basins in northeastern Poland. Concentrations in roach ranged from 20 to 124 μg kg-1 of Pb and from 1 to 19 μg kg-1 of Cd. In bream they were from 4 to 280 μg kg-1 of Pb and 2 to 28 μg kg-1 of Cd, while in carp they were from 9 to 82 μg kg-1 of Pb and 2 to 260 μg kg-1 of Cd. The metal concentrations were low; no result exceeded admissible residue levels set forth by Polish law, and no evident contamination of fish by leakage from the pesticide tomb was detected.