engleski

Bioaccumulation and intracellular distribution of trace elements in the liver of northern pike (Esox lucius L., 1758) from the Mrežnica River: the METABIOM project

The METABIOM project was designed to detect the consequences of increased metal exposure in aquatic biota in the Mrežnica River at the site of historical contamination originating from the cotton industry in Duga Resa in comparison to upstream and downstream locations. In northern pike (Esox lucius), increased hepatic bioaccumulation was observed at the former factory site for Ag, Bi, Cd, Cu, Rb, V, and Zn, which could be associated to higher concentrations of some elements in the river sediment and with higher portion of finer sediment fraction (<2 mm) at that site. Increased Mo, Tl, Mn, Co and As levels at the upstream site indicated possible agricultural origin. Cesium and Fe were the highest at downstream location. High metal presence in hepatic cytosols, indicating higher potential for toxic effects, was found for Cd, Cs, Cu, Rb (>90%), Ag, Bi, Co, and Zn (71-90%). For ten elements, the analysis by size exclusion HPLC revealed the molecular masses of cytosolic biomolecules which bind specific metals in E. lucius liver. The results indicated the predominant binding of Ag, Cd, and Cu to metallothioneins (MTs) and, thus, their presumable complete detoxification under studied conditions. Probable binding to MTs was also observed for Bi and Zn, which were, however, additionally present in the high (>100 kDa) and medium (30-100 kDa) molecular mass protein fractions. The results of the present study will contribute to better understanding of the impact of discontinued contamination sources on aquatic biota, as well as of metal bioaccumulation patterns in E. lucius.

fish ; metallothionein ; metals ; proteins ; size exclusion HPLC

nije evidentirano