Metal levels in sediments and caged mussels in one of the industrial zones of the Eastern Aegean Sea.

Caged mussels make biomonitoring studies possible with their ability to take up pollutants in the industrial zones. The goal of this study was applied to assess metal levels in the biomonitoring organism Mytillus galloprovincialis Lamark, 1819 for transplantation from three locations for two periods (2016-2018) in the industrial zone of the Eastern Aegean Sea. Metals were also determined in sediments; high concentrations of Hg, As and Zn in surficial sediments of Nemrut Bay can cause hazardous impacts on the aquatic environment with respect to sediment quality guidelines. The highest contamination factor (Cf) was calculated for Hg (Cf = 10), suggesting serious anthropogenic pollution in the study area. According to Pearson product-moment correlation analysis, As is not correlated with other metals due to As mainly originating from natural sources. Hg, Cd, Pb and Cu concentrations increased in the transplanted mussels during a field transplant experiment because of chronic pollution from industrial activities. Cumulative effects of both the oil refinery and shipbreaking industry cause higher uptake of Hg, Cd, Pb and Cu in sampling station 3 as a result of higher exposure levels in transplanted mussels. Mussel consumption was compared with provisional maximum tolerable intake from literature; the estimated provisional intake (EDI) for Cd, Hg and Pb does not exceed maximum levels; however, Cu and Zn exceed reference EDI values. Since Nemrut Bay is heavily influenced by industrialisation, it is not a suitable region for seafood production.

Monitoring of polycyclic aromatic hydrocarbons in transplanted mussels (Mytilus galloprovincialis) and sediments in the coastal region of Nemrut Bay (Eastern Aegean Sea).

Polycyclic aromatic hydrocarbons (PAHs) were determined in the coastal region of Nemrut Bay, Eastern Aegean. Sediment and caged mussels were evaluated for sixteen PAHs. High contamination was observed in the sediment sampling sites next to the petrochemical refinery. Low molecular weight PAH levels were dominant in the sediments and the ratio LMW/HMW were higher than one, indicating petrogenic origin pollution. The m-ERM-q values of the sediments were classified as high-priority sites near the refinery while other sites were categorized as medium-low sites. 4-ring PAHs were found to be dominant in the mussels. PAHs were originated from petroleum and mixed sources (petrogenic, pyrogenic) both two transplantation experiments. The assessment of human health risk based on the Carcinogenic `Toxic Equivalents suggested that the mussels have high capability to give rise to carcinogenic risks. PAH levels in the mussels were above the Recommended Total Carcinogenic PAH limits set by the European Union.

The structure of Mediterranean rocky reef ecosystems across environmental and human gradients, and conservation implications.

Historical exploitation of the Mediterranean Sea and the absence of rigorous baselines makes it difficult to evaluate the current health of the marine ecosystems and the efficacy of conservation actions at the ecosystem level. Here we establish the first current baseline and gradient of ecosystem structure of nearshore rocky reefs at the Mediterranean scale. We conducted underwater surveys in 14 marine protected areas and 18 open access sites across the Mediterranean, and across a 31-fold range of fish biomass (from 3.8 to 118 g m(-2)). Our data showed remarkable variation in the structure of rocky reef ecosystems. Multivariate analysis showed three alternative community states: (1) large fish biomass and reefs dominated by non-canopy algae, (2) lower fish biomass but abundant native algal canopies and suspension feeders, and (3) low fish biomass and extensive barrens, with areas covered by turf algae. Our results suggest that the healthiest shallow rocky reef ecosystems in the Mediterranean have both large fish and algal biomass. Protection level and primary production were the only variables significantly correlated to community biomass structure. Fish biomass was significantly larger in well-enforced no-take marine reserves, but there were no significant differences between multi-use marine protected areas (which allow some fishing) and open access areas at the regional scale. The gradients reported here represent a trajectory of degradation that can be used to assess the health of any similar habitat in the Mediterranean, and to evaluate the efficacy of marine protected areas.