Toxic metals in tissues of fishes from the Black Sea and associated human health risk exposure.

The anthropogenic activities in the Black Sea area are responsible for toxic metal contamination of sea food products. In this study, several toxic metals: cadmium, lead, nickel, chromium, and copper were quantified in different tissues (digestive tract, muscle, skeleton, skin) of nine fish species (Neogobius melanostomus, Belone belone, Solea solea, Trachurus mediterraneus ponticus, Sardina pilchardus, Engraulis encrasicolus, Pomatomus saltatrix, Sprattus sprattus, Scorpaena porcus) by using atomic absorption spectrometer with a high-resolution continuum source and graphite furnace technique (HR-CS GF-AAS), and the risk of fish meat consumption by the young human population was evaluated. These metals are used in high amounts in industries located near the coastline such as shipyard construction and industrial plants. Toxic metal accumulation depends on fish feeding behavior, abiotic conditions, metal chemistry, and animal physiology. For instance, cadmium was measured in the muscle of the investigated species and average values of 0.0008-0.0338 mg kg-1 were obtained. The lowest average value of this metal was measured at benthic species N. melanostomus and the highest at the pelagic predator T. mediterraneus ponticus. Generally, the highest metal concentration was measured in the digestive tract that has the role of biofilter for these contaminants. The risk of contamination is significantly reduced by avoiding the consumption of certain fish tissues (digestive tract and skin for copper and skeleton for nickel). An estimation of the dietary metal intake to young consumers was realized for each of the studied species of fish from Romanian, Bulgarian, and Turkish waters, during the period 2001-2014 in order to evaluate the risks of chronic exposure in time due to metal toxicity. This estimation is important for the prevention of chronic exposure due to metal toxicity. Food exposure to studied metals showed a negative trend for Romania, Turkey, and Bulgaria based on the data provided by this study. The young consumers were highly exposed to these elements during the 2001-2006 period as proven by the results from this study.