Danijela Joksimović

Trace metal concentrations in Mediterranean blue mussel and surface sediments and evaluation of the mussels quality and possible risks of high human consumption

The concentrations of trace metals (Fe, Zn, Mn, Ni, Cu, Co and Cr) were determined for the first time in Mediterranean blue mussels (Mytilus galloprovincialis) and surface sediments. The mussel and sediment samples were collected from five sites on the Montenegrin coastal area (southeastern Adriatic Sea) in the fall of 2005 and 2006. The collected samples were digested with a microwave digestion system. The maximum Fe, Zn, Mn, Ni, Cu, Co and Cr mean concentrations in the mussel samples were 603.0, 345.0, 85.0, 18.9, 17.2, 9.1 and 4.2mg/kg of sample dry weight, respectively. The maximum Fe, Mn, Cr, Ni, Zn, Cu and Co concentrations in the sediment samples were 40867, 943.0, 382.0, 336.0, 67.2, 24.8 and 16.9mg/kg of sample dry weight, respectively. A correlation between the metal levels found in the mussel soft tissues with those found in sediments, for both 2005 and 2006, could be established, except for the levels of Zn observed.

Can the origin of some metals in the seagrass Posidonia oceanica be determined by the indexes of metals pollutions

To assess metal pollution, Fe, Mn, Cu, Zn, Pb, Ni, Co, As, Cd, and Hg contents in samples of the seagrass Posidonia oceanica and surface sediment, collected at eight locations along the Montenegrin coast, were determined. The metal pollution index (MPI) and metal enrichment factor (EF) were then calculated. MPI and EF were lower in sediment than in P. oceanica at the same locations. This was very evident for EF values of Hg and Cd. Based on the Pearson’s correlations and EF values, it was possible to conclude that the last two metals’ content in the seagrass did not originate from the crustal sources or natural weathering processes.

Comparative assessment of cardiac activity and DNA damage in haemocytes of the Mediterranean mussel Mytilus galloprovincialis in exposure to tributyltin chloride

This study gives an insight in sensitivity of heart rate (Hr) of Mytilus galloprovincialis as a physiological biomarker. Impact of tributyltin chloride (TBT-Cl) on Hr was studied in parallel with evaluation of mutagenic, genotoxic and cytotoxic potential of TBT-Cl (10, 100 and 1000μg/L) within 96h treatment in static conditions. Mutagenic potential was assessed by SOS/umuC assay while genotoxicity was assessed in haemocytes of M. galloprovincialis by using the comet assay and the micronucleus test. Benzo(a)pyrene (B(a)P) was used as a positive control. Hr variations detected in TBT-Cl treatments can be linked to data obtained in the genotoxicological assays indicating that Hr can be considered and used as a reliable physiological biomarker for detecting the presence of organotin compounds. However despite the observed genotoxic potential of B(a)P, a noteworthy Hr response was not observed which further questions the potential of Hr in the detection of different types of pollutants.

Determination of trace metals in Mytilus galloprovincialis along the Boka Kotorska Bay, Montenegrin coast

The concentrations of six trace metals, cadmium (Cd), copper (Cu), chromium (Cr), lead (Pb), zinc (Zn) and mercury (Hg) were determined in the soft tissues of the mussel Mytilus galloprovincialis and bottom sediments collected from the coastal area of Boka Kotorska Bay (Montenegrin coast). The mussels and sediment samples were collected at three sites along the Boka Kotorska Bay from the autumn of 2014 to the winter of 2016. The concentrations (mg/kg dw) of these metals in the mussel samples ranged from 1.01 to 2.87 for Cd, 6.08 to 13.2 for Cu, 1.37 to 3.55 for Pb, 85.6 to 241 for Zn, 0.72 to 4.05 for Cr and 0.098 to 0.269 for Hg. The concentrations (mg/kg dw) of these metals in the sediment samples ranged from 0.16 to 0.39 for Cd, 4.32 to 48.2 for Cu, 7.02 to 49.8 for Pb, 22.0 to 158 for Zn, 93.1 to 317 for Cr and 0.035 to 0.497 for Hg. The metal content in the mussel samples and the metal content in the sediment collected from three locations over four different seasons were analyzed using the Pearson correlation coefficient (r) and cluster analysis (CA). A correlation between the metal levels found in the mussel soft tissues with those found in the sediments, for both 2014 and 2015, were established. The metal pollution indexes (MPI) for the sediment and mussels were compared, indicating that the most polluted sediment was at the location Institute of Marine Biology Kotor (IBMK) and the most polluted mussels were sampled from the Zanjice location.

Human exposure to trace elements via consumption of mussels Mytilus galloprovincialis from Boka Kotorska Bay, Montenegro

In order to assess human health risks via consumption of potentially toxic mussels, the concentrations of Al, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Ni, Pb, Sr, Zn and Hg were studied in Mytilus galloprovincialis collected from the coastal area of Montenegro. By two approaches for the human health risk assessment (HHRA), considering oral reference doses by the United States Environmental Protection Agency (US EPA) and provisional tolerable intakes by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), it has been revealed that despite the fact that trace element levels do not exceed the defined limits for mussels, they can be limiting factors for the mussel consumption. Specifically, it was noticed that the levels of Co, Pb, Cd and Li could be the limiting factors for the consumption of mussels from this coastal area. Al and Li data obtained in this study are especially important since these two elements have not been previously studied in M. galloprovincialis. Furthermore, taking into account the significant differences in concentrations of elements in different seasons, the study confirmed the starting assumption that in the calculations for the HHRA the average concentrations of elements in samples taken in different seasons during a longer period should be used.

The impacts of seawater physicochemical parameters and sediment metal contents on trace metal concentrations in mussels—a chemometric approach

The concentrations of Al, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Ni, Pb, Sr, Zn, and Hg were studied in Mytilus galloprovincialis collected from the coastal area of Montenegro. The impact of seawater temperature, salinity, dissolved oxygen, total organic carbon (TOC), and metal content in sediment samples on the metal contents in mussels collected from three locations in four different seasons was analyzed by a Pearson correlation coefficient (r), principal component analysis (PCA), and cluster analysis (CA). These analyses were used to discriminate groups of samples, elements, and seawater parameters, according to similarity of samples chemical composition in different seasons, as well as the impact of seawater parameters and surface sediment composition on the mussels’ element concentrations. Synergistic interactions occurred between seawater TOC, Fe, and Al concentrations in mussels. Compared with other studies, which are usually performed under constant laboratory conditions where mussels undergo only one stress at a time, this study was performed in nature. The analyses showed the importance of considering simultaneously acting environmental parameters that make determining of separate impacts of each factor selected very difficult and complex.

Marine Chemistry of the Boka Kotorska Bay

Currently, in the country and abroad, numerous investigations focused on analysis of environmental protection and improvement, particularly water as a sensitive and limited resource, are being conducted. One of main environmental tasks is water quality monitoring, i.e. monitoring of the possible presence of harmful substances as well as determining their concentrations in water. Monitoring of marine environment trace metals pollution, which represent a basis for the control of pollution of the marine environment, is usually limited not only by performance and detection limits of the existing analytical techniques, but also by the general lack of interest, since rivers and oceans have for quite some time been used for disposal of various wastes.