Differences in Trace Element Content between Non-Indigenous Farmed and Invasive Bivalve Mollusks of the South African Coast

contents of 23 trace elements (Sc, V, Cr, Mn, Fe, Co, Zn, As, Se, Br, Rb, Sr, Mo, Ag, Sb, I, Ba, La, Ce, Sm, Eu, Hf, Ta) were quantitatively determined in soft tissues and shells of mass non-indigenous bivalve mussels—farmed Pacific oysters (Crassostrea gigas) and farmed and wild invasive Mediterranean mussels (Mytilus galloprovincialis) at the Atlantic coast of South Africa. The study revealed that the contents of the majority of elements in the soft tissues of both species were higher than those in the shells. The tissues of wild invasive Mediterranean mussels contain higher levels of a range of trace elements comparing to farmed mussels. The tissues of Pacific oysters contain much higher levels of almost all elements studied compared to the tissues of Mediterranean mussels. Higher content of zinc in the mussels and oysters from Saldanha Bay may evidence anthropogenic pollution of the bay’s ecosystem by this metal, which necessitates continued monitoring of levels of potentially toxic metals. Both alien species, and especially Pacific oysters, may serve as reliable biomonitors for trace elements in marine ecosystems. Both species are rich in essential elements and provide nutritionally-valuable seafoods.

Assessment of Mercury in Diagnostic Biomaterials of Different Population Groups in Urban Areas of the Moscow Region

The results of a survey of different population groups in urban areas of the Moscow Region (industry workers, residents of areas with increased anthropogenic load of mercury and conditionally pristine areas, cohorts of pregnant women and children) to assess the contents of mercury in samples of various diagnostic biomaterials taken during the course of research are presented. Mercury concentrations in venous and umbilical cord blood, urine, hair, and nails were determined by means of instrumental neutron activation analysis and cold vapor atomic absorption spectrometry. Peculiarities of selection, transportation, storage, and preparation for analysis of samples of hair, nails, urine and umbilical venous blood are described. The determined concentrations of mercury in the studied diagnostic biomaterials are compared with normal and thresholds values. Although increased mercury concentrations were observed in some cases, no significant exposure of mercury was evident in general in the study towns. A positive correlation between the degree of consumption of seafood during pregnancy and a high content of mercury in the analyzed diagnostic biomaterials was shown.

Estimation of Mercury Intake from Consumption of Fish and Seafood in Russia

Data on the mercury concentration in freshwater and marine fish and seafood on the territory of Russia are presented. The level and pattern of the fish and seafood consumption in various regions of Russia are found from the analysis of open statistics. Regions with the maximum and minimum consumption of fish products are established. Mercury intake from these products in a human organism is calculated. It is shown that at the current level and pattern of the diet in Russia fish cannot be a source of high mercury concentrations in a human organism.