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.

Environmental impact of fish farming: assessment of metal contamination and sediment geochemistry at three aquaculture areas from the eastern Aegean coast.

Metal contamination and geochemistry of surface sediments were assessed at three aquaculture sites from the eastern Aegean coast. The chlorophyll degradation products and organic carbon levels were used as indicators of eutrophication status. In Akköy, higher Hg, Pb, and Cd levels were observed around the cages, while maximum concentrations of other elements were determined at stations situated near the Büyük Menderes River estuary. Metal concentrations were less than the central Aegean coast background levels other than Zn, Ni, and Cr in Akköy. Several approximations have been utilized to evaluate potential toxicity of sediments and sediment quality guidelines (SQG) were used to estimate the risks for aquatic life. Ni was the only metal with concentrations exceeding all SQG values, which indicates the highest adverse biological effect in Ildir, Akköy, and occasionally toxic in Güllük. Based on QPEL and QTEL, Ni and Cr were the predominant metal contaminants in all areas. Similarly, Cr and Ni account for the most of the all sediment toxicity in the aquaculture areas according to toxic risk index. It is concluded that sediments around the fish farms are affected by growing input of elements because of aquaculture activity. The levels of chlorophyll degradation products showed oligotrophic and mesotrophic conditions in the three studied aquaculture areas.

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.

Potential risk assessment of metals in edible fish species for human consumption from the Eastern Aegean Sea.

The levels of Hg, Cd, Pb, Cr, Cu and Zn were measured in the tissues of four edible fish species namely: Diplodus annularis, Pagellus erythrinus, Merluccius merluccius and Mullus barbatus, collected from the Turkish Coast of the Aegean Sea. Except for D. annularis, the levels of Cd and Pb in all fish tissues sampled in Aliaga Bay in 2009 were above the tolerable limits according to the Food and Agriculture Organization of the United Nations (FAO). Hg in P. erythrinus and M. barbatus were higher than the maximum permitted limits (FAO), while D. annularis and M. merluccius were lower than the limit for biota in the district of Aliaga. Although the Target Hazard Quotient (THQ) values for Cd, Pb, Cu, Cr, Zn in all fish samples were lower than 1.0, the THQ for Hg levels were higher than 1.0 for most of the samples. According to the THQ values, M. merluccius may be consumed in moderation from Aliaga Bay, while the consumption of M. barbatus and P. erythrinus collected from Aliaga Bay are potentially hazardous to human health due to the Hg concentrations. Fish collected from Izmir Bay can be consumed safely.

Heavy metal concentrations in surficial and core sediments from Izmir Bay: an assessment of contamination and comparison against sediment quality benchmarks.

The levels of heavy metals were determined in surface and core sediments from the Izmir Bay in 2009. The highest concentrations of As, Cr, Cu, Ni, Pb and Zn were found in the inner bay due to industrial activities. In contrast, maximum levels of Mn, Co, Fe and Al were observed in the outer bay, due to geochemical structure. Cu, Pb, Zn, Ni, As, Cr and Co levels in the upper layer of core sediments were higher than the mean background values of bottom sediments. The enrichment of Cr, Mn, Pb, Zn, Cu and As in the bay seems to be driven by anthropogenic sources. It was found that the sediments in Izmir Inner Bay were generally polluted heavily with Cu, As, Ni, Cr, Pb and moderately with Zn according to the numerical Sediment quality guidelines of the USEPA.

Distribution and sources of polycyclic aromatic hydrocarbons in Cilician Basin shelf sediments (NE Mediterranean).

This study corresponds to preliminary work representing an initial assessment for spatial distribution of polycyclic aromatic hydrocarbons (PAHs) in the Cilician Basin coastal sediments. The concentrations of PAHs in shelf sediments were determined from the three different regions of Cilician Basin (Eastern Mediterranean) in 2011. Concentrations of PAHs were low 5.43-271 ng g(-1) with respect to other coastal sediments in the Mediterranean and these results could be compared with concentrations found in open sea areas. PAH composed mainly of pyrolytic four and five-ring compounds. An abundance of high molecular weight PAHs indicated that atmospheric particles and urban aerosols are the major input route of hydrocarbons in the Cilician and Lattakia Basins. PAH levels were assessed in accordance with numerical Sediment Quality Guideline (SQG) of the USEPA. The results showed that no samples exceeded biological thresholds to pose biological impairments.

Marine organic pollutants of the Eastern Aegean: aliphatic and polycyclic aromatic hydrocarbons in Candarli Gulf surficial sediments.

Aliphatics and PAHs were determined in sediments from the Candarli Gulf in 2009. Aliphatics ranged from 3.88 to 24.7 µg g(-1) while aromatics varied between <4.15 and 405 ng g(-1) (dw). PAHs ranged from a relatively low to a moderate PAHs pollution compared to other urbanized coastal areas worldwide. 3-ring PAHs were most abundant in the sampling area. Both pyrolytic and petrogenic PAHs were present in most samples, although petroleum derived PAHs were dominant at the stations situated near the refinery and petrochemical, metal industry and pyrolytic sources were mainly prevalent in the estuary of Bakircay River. The ratio of UCM to n-alkanes and CPI values in station 6 indicate that the main contribution to petroleum hydrocarbon contamination is via oil and its products. PAH levels at all sites were below the ERL and ERM except fluorene. The results indicated that the sediments should have no potential biological impact except stations 6 and 14.

Aliphatic and polycyclic aromatic hydrocarbons in the surface sediments from the Eastern Aegean: assessment and source recognition of petroleum hydrocarbons.

MATERIALS AND METHODS: Aliphatic and polycyclic aromatic hydrocarbons (PAHs) were determined in surficial sediments from the Aegean Sea in the Eastern Mediterranean in 2008. RESULTS: Total aliphatic hydrocarbons (n-C12 to n-C35) ranged from 330 to 2,660 ng g(-1) dry weight (dwt), while aromatics (19 PAHs) varied between 73.5 and 2,170 ng g(-1) dwt. Total concentrations of both aliphatic hydrocarbons and PAHs ranged from a relatively low to a moderate PAHs pollution compared to other urbanized coastal areas worldwide. PAH consisted mainly of pyrolytic four- to five-ring compounds. Both pyrolytic and petrogenic PAHs are present in most samples, although petroleum-derived PAH are dominant at Izmir Inner Bay (IIB) and Dardanelles Strait, and pyrolytic sources are prevalent in other sampling sites. A high contribution of perylene, a diagenetic originated PAH, to the total penta PAHs was found greater than 70% in Meric River Estuary, Dikili Bay, Candarli Bay, and Gokova Bay sites. CONCLUSION: The spatial distributions of aliphatic hydrocarbons and PAHs indicated that urban runoff and transport from the continental shelf is the major input pathway of anthropogenic and biogenic hydrocarbons from terrestrial sources in the near-shore area. PAH levels at all sites were below the effects range-low (ERL) and effects range-median (ERM) values except fluorene. The average and maximum fluorene concentrations exceeded ERL, but below ERM, in the IIB. Meanwhile, the concentration levels of naphthalene, fluorene, phenanthrene, fluoranthene, pyrene, benzo[a]anthracene, and chrysene were higher than threshold effect level values at the same site, but all these compounds were significantly lower than the probable effect level values. The results indicated that the sediments should have potential biological impact.