A novel approach to assess temporal baseline levels of trace metal contamination in the mussel M. galloprovincialis in the Mediterranean, Marmara and Black Seas.

This study reports, for the first time, the baseline levels for fifteen trace metals in M. galloprovincialis tissue from around the Mediterranean, Marmara and Black Seas. The environmental quality in the surrounding seawater was assessed i.e., a mussel farm was investigated by using CF and DC indices, and the water quality was qualified as good for the aquacultural activities. A strong Cu-regulation in the transplanted mussels was observed and it ranged between 3.20 and 3.60 µg/g d.w. The highest bioavailability and bioconcentration of the particulate Fe fraction could present a health risk to consumers with a low risk level (1 < THQ < 9.9). Cr is considered the limiting metal for mussel consumption (< 2 kg/day). The metal contamination gradient was assessed using TEPI and TESVI indices that identified seven reference stations on the large scale and revealed that Cd is the most investigated metal in the literature databases, and found that Pb was the most bioavailable contaminant in the areas examined.

Sediment pollution: An assessment of anthropogenic and geogenic trace element contributions along the central Algerian coast.

Sediment cores from the central Algerian coast were collected to investigate the distribution, sources and risk of trace metals. The local geochemical background of metals was defined from the core S collected in an uncontaminated area of the coast. The anthropogenic inputs in Algiers Bay elevated Ag, Cd, Pb and Zn concentrations as their maximum were 3.1, 3, 2.1 and 1.8 times the background values, respectively. Meanwhile, increased contents of Arsenic (up to 21.1 mg/kg) were detected in all sites. Correlations and PCA suggest that lithogenic sources controlled metal deposition, while most sediment arsenic was agriculture-derived. Organic matter acted as a sink or source for some trace metals. According to EFs, the study area showed slight to moderate enrichment with respect to Ag, As, Pb, Cd, Zn and Cu, whereas they remained uncontaminated with Cr, V, Co and Ni. This study provides a needed baseline for future environmental investigations.

Occurrence, contamination level and ecological risk assessment of dissolved and particulate trace elements in rivers entering the southwestern Mediterranean Sea.

Metal pollution in rivers should not be overlooked before their entry into the sea. However, there are few studies for estimating such contamination in rivers entering the Algerian coastal waters. Semimonthly quantification of dissolved and particulate metals, near the mouths of two industrial-tainted rivers, El Harrach and Mazafran rivers, was carried out during a period of one year. All the trace metals analyzed are originating from anthropogenic sources (EF > 1.5), with higher contamination of dissolved Pb, Cd, Zn and Ni and a slight degree of contamination of particulate Cu and Zn (0 < Igeo < 1). Particulate metals show a stable complex with the particulate phase (e.g. 2 < LogKd < 6). The risk assessment results indicate that particulate Pb and Zn have a 33% likelihood of toxicity for adverse biological effects. A significant toxicity effect (ΣTUi >4) of the combined particulate metals (Pb, Cd, Cu, Zn, Cr, Ni and As) was primarily due to the higher particulate Cd, Zn, and Cr availability.

Effect of physiological conditions and biochemical factors of mussels Mytilus galloprovincialis in radioactivity monitoring programs along the Algerian coast.

A study was carried out to determine the activities of radionuclides (137Cs, 40K, 226Ra, 214Bi, 214Pb, and 210Pb) and the levels of biochemical components (lipids, carbohydrates, and proteins) in mussels (Mytilus galloprovincialis) along the Algerian coast. The goal was to evaluate the effect of mussels' biological parameters on radionuclide concentrations, through two coastal water biomonitoring programs. The mussels were taken from three study areas on the Algerian coast: Kristel (Oran), Surcouf (Alger), and Collo (Skikda), for the passive biomonitoring program and transplanted from each study area into the control site of Surcouf. Biochemical components were determined by means of UV-visible colorimetric assays, while the activity concentrations of radionuclides were measured by gamma-ray spectrometry. The results showed that carbohydrates were the most abundant biochemical components (40-60%) compared with proteins (20-40%) and lipids (15-20%). 137Cs activity concentrations were below the lower limit of detection (LOD) for all samples, while the high activities of 40K are the result of its behavior as stabile potassium K which is extensively used in the metabolism of mussels reflects the conditional state of mussels. 210Pb concentration reflects the conditional state of mussels (morphometric parameters and proteins content). The mussels' bioaccumulation capacity for radionuclides was found to be dependent on the growing site and the biomonitoring time period.

Environmental and human health risk assessment of trace metals in the mussel ecosystem from the Southwestern Mediterranean.

This study evaluates the geographical distribution of Pb, Cd, Cr, Ni, Co, Cu, Zn, Mn and Fe in wild mussels Mytilus galloprovincialis as well as in associated suspended particulate matter (SPM) and sediments from the Algerian coast. The bioaccumulation (metal concentrations in tissue), bioavailability (metal indices) and bioconcentration of trace metals from the adjacent environment were assessed. The computed pollution load index (PLI) indicates that the sediments are not polluted by these metals, except for Zn which shows a moderate level of contamination. All the metals in SPM samples are in a 'safe range' with respect to the computed degree of contamination (DC < 2). The target hazard quotients (THQ) and the hazard index (HI) values indicate a risk level with Fe. However, the Cr measured in mussels is considered 'extreme', according to the consumption rate limit for mussels (CRlim) which limits their consumption to 0.5 kg/day.