Levels of trace metals and effect of body size on metal content and concentration in Arctica islandica L. (Mollusca: Bivalvia) from Kiel Bay, Western Baltic

The levels of four trace metals (Cd, Cu, Pb, and Zn) in the whole soft body and in different organs of the ocean quahog Arctica islandica were evaluated from four stations in Kiel Bay, Western Baltic. The relationships between the contents and concentrations of these metals and body size (weight and length) were also investigated. Double logarithmic plots of metal contents and concentrations against dry body weight and shell length, respectively, show straight-line relationships. The results indicate that smaller individuals have higher concentrations of Cu and Zn, two essential metals, while larger individuals have higher concentrations of Cd and Pb, two non-essential metals. The calculated regression slopes of metal content against dry-body weight revealed that Cd and Cu appear to be affected by maturation since two different slopes are observed for both metals before and after maturation. This was not obvious for Pb and Zn. Pooled slopes of metal content against dry-body weight for all animal sizes indicated that Cu and Zn have a one common slope of (0.82) and Cd and Pb another common one of (1.51). Plots of metal concentrations against shell length indicated also that Cu and Zn have one common slope of (−0.54) and Cd and Pb another one of (1.56). Moreover, it was possible to calculate one final slope of (1.53) for Cd and Pb from both content/weight and concentration/length plots. This indicates that A. islandica may have one metabolic strategy for the essential metals and another for the non-essential metals

Fahrtleiterbericht über die 37. Reise von FS "Poseidon" [POS37], 5.3. bis 10.3.1979

Fahrtgebiet: nördliche Nordsee, Skagerrak, Ziel: Forschungs- und Sammelfahr

Trace metal accumulation in hair and skin of the harbour seal, Phoca vitulina

Skin and hair samples of harbour seals (Phoca vitulina) found dead along the west coast of northern Germany in 1988 were analysed for total mercury, cadmium and lead. Cadmium and lead concentrations were below the detection limit in most skin samples. The mercury content of the hair (median: 23.1 μg g−1 wet wt) was several magnitudes higher than the mercury content of the skin (0.27 μg g−1 wet wt). Mercury concentrations in hair samples were significantly higher than lead concentrations (0.54 μg g−1 wet wt), which significantly exceeded cadmium levels (0.09 μg g−1 wet wt). Female seals revealed lower cadmium concentrations in the hair than male seals. Accumulations of metals with age were observed for cadmium and lead in hair samples and for mercury in skin samples of male seals. A connection between metal accumulation and pigmentation or rather moult was clearly recognizable

Eine bakterielle Inaktivierung des Steroidhormons Ecdysteron

Aus einer wäßrigen Lösung des Crustaceenäautungshormons Ecdysteron wurden Bakterien in Reinkultur isoliert, die das Hormon abzubauen vermögen. Die mögliche Bedeutung der bakteriellen Inaktivierung des Ecdysterons wird diskutiert. A bacterium which is able to degrade the crustacean malting hormone ecdysterone was isolated from an aqueous solution of the hormone. The possible significance of this inactivation by bacteria is discussed