Bioaccumulation of heavy metals in marine organisms from the Romanian sector of the Black Sea

Abstract

The aim of this research was to study the accumulation of heavy metals (cadmium - Cd, lead - Pb, chromium - Cr, nickel - Ni, and copper - Cu) from water and sediments into living tissues of relevant marine species from different trophic levels of a food web, representative for shallow waters of the Romanian Black Sea Coast where the main anthropogenic impacts exist. The heavy metals concentrations were analysed by using an Atomic Absorption Spectrometer with graphite furnace, the results being further used to calculate the bioconcentration factors for a few key taxa like green and red algae, molluscs and fishes. Seven sampling sites influenced by anthropogenic pollution sources (municipal wastewater treatment plants and diffuse sources) were considered and a total of 300 samples were analysed for the period 2011-2012, this being the first unitary study for the Romanian Black Sea marine ecosystem. In 2011 and 2012 there were no significant differences between the sampling areas considering the heavy metals concentrations in water. For the sediments significant differences were observed between sampling sites for some heavy metals, namely Pb in 2011 and Pb, Cu and Cd in 2012, the highest concentrations being registered in the southern sector of the Romanian Black Sea shore, where the anthropogenic pollution sources are represented by the harbour and wastewater treatment plants. The values of the bioaccumulation factors (BCFsed) shows that algae are good accumulators for Cu>Pb>Ni>Cr>Cd, in comparison with BCFwater where the order of heavy metal accumulation was different: Cr>Ni>Pb>Cd>Cu. Molluscs have higher bioconcentration factors for Cu and Cd for sediments and for Cu and Ni for water. Rapana venosa accumulated more Cd and Cu. For fishes, Pb, Cu and Ni had the highest values in the tissues of benthonic species Mullus barbatus. In bivalve molluscs and fishes, in the majority of cases, there were not recorded exceeding mean concentrations as compared to the maximum allowed concentrations for Cd and Pb.

Cadmium tolerance and accumulation characteristics of wetland emergent plants under hydroponic conditions

“…The capacities of the four plants to accumulate Cd were evaluated based on the Cd uptake per plant, the bioaccumulation factor (BCF), and the translocation factor (TCF). BCF this study is dened as the ratio of total metal concentration in shoots to that in water, which is an indicator of the ability to uptake and transport metals to the shoots; 20,21 TCF is dened as the ratio of heavy metal concentration in the shoot to that in the root. 22…”

First data on three bivalve species exposed to an intra-harbour polymetallic contamination (La Rochelle, France)

“…Statistic correlation tests were carried out to investigate relationships between inorganic pollutants and specific activity of biomarkers in order to determine the best bioindicator species for longer-term studies in the La Rochelle harbour. Indeed, it now seems necessary to bridge both, bioaccumulation and enzymatic data, which have not been covered together in previous reports on bivalve species in harbours (Caro et al, 2015;Hussein and Khaled, 2014;Walker and MacAskill, 2014;Jebali et al, 2014;Conte et al, 2015;Jitar et al, 2015;Walker and Grant, 2015).…”

Laboratory tests for the phytoextraction of heavy metals from polluted harbor sediments using aquatic plants

“…The BCF is calculated using the formula: BCF=Concentration of metal in the plant/Concentration of metal in water (Jitar et al, 2015).…”