Trace Element Concentrations in Mussels (Mytilus galloprovincialis) from the Gulf of Trieste, Slovenia

Abstract

ABSTRACT The concentrations of the trace elements zinc (Zn), arsenic (As), manganese (Mn), copper (Cu), chromium (Cr), nickel (Ni), cobalt (Co), cadmium (Cd), lead (Pb), mercury (Hg), and iron (Fe) were examined in Mediterranean blue mussels (Mytilus galloprovincialis) from the Northern Adriatic Sea to determine whether there were site differences and seasonal variations in metal concentrations and to evaluate the potential health risks of consumption of these mussels to humans. Mussels were collected between January and October 2015 from three Slovenian shellfish harvesting areas and from a lighthouse near Debeli Rtič. The concentrations of elements were determined using inductively coupled plasma mass spectrometry. The amount of each element decreased in the following order: Fe > Zn > (As, Mn) > (Cu, Cr) > (Ni, Co) > (Cd, Pb) > Hg. Statistical analysis revealed that time, that is, the month of sampling, significantly affected the concentrations of elements in mussels (P < 0.05). The concentrations of Cr, Mn, Fe, Ni, Hg, and Pb were highest between January and March and lowest between May and September. The concentrations of other elements in mussels were not higher or lower for several consecutive months, but occasionally (some months) lower or higher content was detected. The sampling site had a statistically significant effect only on the content of Cd, Pb, and Hg in mussels (P < 0.05). The lowest level of these elements was found in mussels from Seča, and the highest levels of Hg and Pb were found in mussels from Debeli Rtič. Debeli Rtič is, among all sampling points, closest to the outflow of the Soča River that brings heavy metals into the Northern Adriatic Sea from a closed Hg mine. Because the concentrations of Pb, Cd, and Hg in all analyzed samples were below the maximum level permitted by Commission Regulation No 1881/2006, mussels were suitable for human consumption.