Metal Bioaccumulation and Potential Health Risk Assessment in Different Tissues of Three Commercial Fish Species (Merluccius merluccius, Mullus barbatus, and Pagellus erythrinus) from Edremit Bay (Aegean Sea), Turkey.

Metal levels and potential health risk assessment in muscle, liver, and gills of three fish species (Merluccius merluccius, Mullus barbatus, and Pagellus erythrinus) from the Edremit Bay were investigated in spring and autumn 2015. Metal concentrations (Hg, Cd, Pb, Cr, Cu, Zn, Mn, and Fe), metal pollution index, and bioaccumulation factors in P. erythrinus were observed to be generally higher than those in M. barbatus and M. merluccius. Tissue was the main factor that might be responsible from the variations of metals in fish species according to ANOVA and PCA. Hg concentrations in M. barbatus and P. erythrinus were greater than threshold limits defined by international authorities; however, no carcinogenic risks were found for Cd and Pb levels. According to the results, the bay has been negatively influenced by human activities, and further research on monitoring of the biota and sediments is recommended for Edremit Bay and similar coastal areas under human pressure.

A comparative study of two HPLC methods for dissolved monosaccharide analysis in seawater using 2-amino benzamide and 2-amino pyrazine as pre-column derivatization reagents.

Two reversed-phase HPLC methods for molecular analysis of dissolved free monosaccharides in seawater were investigated comparatively by optimizing chromatographic separations and pre-column derivatization reactions. Monosaccharides derivatized with 2-amino benzamide or 2-amino pyrazine, and reduced with 2-picoline borane or 2-dimethylamino borane. According to results of optimization, separation performance, and detection limits, 2-amino benzamide method gave better results than 2-amino pyrazine method. Among 12 monosaccharides tested, it was possible to quantify glucose + galactose, galacturonic acid, glucuronic acid, xylose + arabinose, ribose, mannose, and N-acetyl-d-glucosamine with detection limits between 1.2 and 11 nM with intra-day repeatability of 2-9% and inter-day repeatability of 3-9%. The optimized method has the same level of detection limit with a widely used anion exchange chromatography method. Besides the preliminary results reported in this study, it may be possible to achieve higher sensitivity and to detect more monosaccharides by the use of shorter and narrow-bore columns at different polarities in further studies.

Seasonal variations of multi-biomarker responses to metals and pesticides pollution in M. galloprovincialis and T. decussatus from Homa Lagoon, Eastern Aegean Sea.

Biomarkers (CAT, SOD, GPx, and AChE) were investigated in hepatopancreas and soft tissues of mussels (Mytilus galloprovincialis) and clams (Tapes decussatus) in response to metal and pesticide pollutions in Homa Lagoon. Mussel and clam samples were seasonally collected in January, May, August and November 2015. According to the results, higher metal concentrations determined in the soft tissues of both species in January. Hepatopancreas was found to accumulate higher levels of metals than soft tissue. Metal deposition potential in clams were higher than mussels. Pesticide levels were below detection limits in clams. In mussels, only 4,4'-DDE was detected in soft tissues and hepatopancreas in November. Highest AChE, CAT, SOD and GPx activities in mussels were determined in January. On the other hand, maximum AChE and CAT activities in clams were found in November. Seasonal variations of metals and biomarker levels might be related to species-specific physiology and environmental conditions.

Distributions and Sources of PAHs and OCPs in Surficial Sediments of Edremit Bay (Aegean Sea).

In this study, levels, distributions, and sources of polycyclic aromatic hydrocarbons (18 compounds) and organochlorine pesticides (19 compounds) in surface sediments of 14 stations from Edremit Bay (Aegean Sea) were investigated in April and November 2015. ΣPAH concentrations (0.65-175 ng/g) in Edremit Bay sediments indicated low pollution. ΣPAH levels were decreased in the order of inner (81.1 ± 47.0 ng/g), northern (48.4 ± 15.9 ng/g), and southern (19.0 ± 15.8 ng/g) bays. p,p'-DDE was the only organochlorine pesticide detected in Edremit Bay sediments and found between nd to 1.16 ng/g dw. According to sediment quality guidelines, PAHs and p,p'-DDE levels in Edremit Bay were below the threshold effect level, effect range low, and threshold effect concentration limits and the sediments have no potential ecological risks. Two- to 3-ring PAHs were found at higher levels than 4- to 5-ring PAHs. Molecular PAHs ratios and Principal Component Analysis-Multiple Linear Regression analyses indicated combustion of wood-coal and vehicle emissions might have contributed to PAH levels in the bay.

A survey of metal concentrations in marine sediment cores in the vicinity of an old mercury-mining area in Karaburun, Aegean Sea.

The aim of this study was to assess the historical trends of metal concentrations in coastal sediments in the vicinity of an inactive mining area, find background values and contamination levels of metals around the Karaburun peninsula, and then search for other sources of mercury in marine sediment cores using multivariate statistical analysis and report the potential ecological risks from that metal contamination. Surface sediment samples were taken from seven stations. Water depths were less than 20 m (coastal area) at stations KB07 and KB08. The depths at stations KB01, KB02, and KB03 were between 20 and 40 m, and stations KB05 and KB06 were more than 40 m (open area). In surface sediments at depths between 20 and 40 m, Mo, Cu, Pb, Zn, Ni, Co, Fe, Cd, Ti, Zr, Sn, As, Y, and Hg levels revealed higher contamination factors (Cf) compared to those of the coastal and open areas. Also, sediment samples were taken for historical records at stations KB01 and KB02 for 2012. Metal concentrations of Cu, Zn, Ni, Co, As, Sb, Cr, Ba, Ti, Al, and Hg in the sediment core samples were significantly higher during the Holocene (~5700 BC to 2000 B.C.) and Medieval Warm periods (~1000 A.D. to 1400 A.D.) and tended to decrease towards the Little Ice Age (2200 B.C. to the birth of Jesus Christ). Background concentration of Hg in sediment was found as 1.67 µg/g around the Karaburun peninsula. Average EF values higher than 20 were identified for As, Hg, Sb, and Ca. Ni and Hg levels were found above the PEL values. It was determined that the accumulation effect of Hg coming from the mafic rocks due to erosion in the marine environment was higher than that of Hg coming from the mine. The factor analyses showed an association between Hg, Ni, and Co. This reveals the importance of the contribution of mafic rocks reaching the marine environment by wave erosion. According to the factor analyses, high concentrations of Pb, Zn, Cd, As, Sb, Ba, Ti, and Zr were detected in the lithogenic sources.

Spatial variations in polycyclic aromatic hydrocarbons concentrations at surface sediments from the Cyprus (Eastern Mediterranean): relation to ecological risk assessment.

The objective of the present study was to evaluate the distribution, sources, origins, and environmental risk assessment of polycyclic aromatic hydrocarbons (16 US EPA priority pollutants) pollution in 23 surface sediments from Cyprus coast. The mean total polycyclic aromatic hydrocarbons (PAHs) concentrations in the sediments from Gemi Konagi, Girne and Gazi Magusa areas were found 47, 52 and 50 ng/g, respectively. Molecular ratios and principle component analysis indicated that PAH pollution originated mainly from fossil sources, with higher pyrolytic contributions. The 2-3 ring PAHs were dominant in Cyprus sediments. Concentrations of PAHs observed in this study were compared with available soil quality guidelines and the concentrations were lower than the guideline values. The guideline values suggested that the Cyprus sediments were likely to be not contaminated by toxic PAH compounds.

Polycyclic aromatic and aliphatic hydrocarbons pollution at the coast of Aliaga (Turkey) ship recycling zone.

Aliaga Bay is one of the most important maritime zones of Turkey where shipping activity, shipbreaking industry, steel works and petrochemical complexes exist together. Polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons in sediment of the Aliaga Bay were investigated to evaluate an environmental risk assessment from PAHs contamination in 2009-2010. Aliphatic and PAHs diagnostic ratios were showed to be mainly petroleum-originated and pyrolitic contaminations, respectively. The TEL/PEL analysis suggests that Aliaga sediments were likely to be contaminated by acutely toxic PAH compounds.

Heavy metals contamination levels at the Coast of Aliaga (Turkey) ship recycling zone.

Aliaga Bay is one of the most important maritime zones of Turkey where shipping activity, shipbreaking industry, steel works and petrochemical complexes exist together. Concentrations of heavy metals and organic carbon in sediment of the Aliaga Bay were investigated to evaluate an environmental risk assessment from metals contamination in 2009-2010. Comparison of the metal concentrations with average shale and Mediterranean background levels revealed that most of the samples from the Aliaga were polluted with Hg, Cd, Pb, Cr, Cu, Zn, Mn and Ni. It was found that Hg, Pb, Cu, Zn and Ni levels in Aliaga Bay exceeded the PEL values. Sediments, contaminated with Pb, Cr, Cu, Zn and Ni were considered as heavily polluted per the SQG.

A case study of trace metals in suspended particulate matter and biota before wastewater treatment plant from the Izmir Bay, Turkey.

The concentrations of trace metals (Cu, Zn, Mn, Ni, and Fe) from suspended particulate matter (SPM) and biota in Izmir Bay (Eastern Aegean Sea) were studied in order to evaluate the environmental impact of the anthropogenic metals before building of Wastewater Treatment Plant. SPM samples were collected in wet and dry periods from Izmir Bay. Metal concentrations in SPM (Cu, 0.36-2.19; Mn, 0.07-11.3; Ni, 0.43-7.81; Zn, 7.33-269; Fe, 1.00-266 µg dm(-3)) were comparable to those reported for other moderately polluted bays. Maximum metal concentrations in SPM were observed during summer season. SPM metal concentrations displayed a clear spatial trend with values increasing with proximity to urban centers. Cu and Zn concentrations in SPM were especially high in the inner bay. SPM were found to be contaminated by Zn. The vertical profile of Mn, Zn, and Ni concentrations in SPM had a maximal value at the upper layer and decreased to minimal value at the bottom layer of the inner bay in summer, in contrast to the observed pattern of Fe and Cu. Maximum Cu concentrations were obtained in Penaeus kerathurus. Also, maximum Zn and Fe concentrations were found in Mytilus galloprovincialis. Relatively high Cu levels were found in Sardina pilcardus and Mullus barbatus than other fish species. Besides, Cu levels were lower in Diplodus annularis and Merluccius merluccius. Finally, metal levels in biota tissues were lower than the limits of European Dietary Standards and Guidelines.

Sediment concentrations of heavy metals in the Homa Lagoon (Eastern Aegean Sea): assessment of contamination and ecological risks.

The concentrations of heavy metals and organic carbon in sediment of the Homa Lagoon which is one of the most productive lagoons and commercial important active fish trap in the Eastern Aegean Sea, were investigated in order to describe the temporal and spatial distributions of metals. These results were used to evaluate possible ecological risks that could be a problem for the environment of the lagoon in the future. Sediments were enriched with Cr, Ni and considered as heavily polluted per the SQG. The C(f) of Ni and Cr were presented moderate level of contamination in this area. The C(d) levels indicated moderate degree of contamination at station B, C, D and E due to agricultural drainage water, industrial and domestic wastewater, are transported by the Gediz River. Sediments from Homa Lagoon were most toxic for Ni due to exceedances of the TEL and PEL values.

Evaluations of heavy metal pollution in sediment and Mullus barbatus from the Izmir Bay (Eastern Aegean) during 1997-2009.

Izmir Bay is one of the great natural bays of the Mediterranean. The surface sediment and fish samples were collected during 1997-2009. The sediment concentrations of inner bay showed significant enrichments during sampling periods. Outer and middle bays exhibited low levels of metal enrichments except the estuary of Gediz River. The concentrations were generally higher than the background levels from the Mediterranean and Aegean except Cd and Pb levels gradually decreased. Metal EF is used as an index to evaluate anthropogenic influences of metals in sediments. Maximum metal enrichment was found for Hg in the outer bay, while Pb indicated maximum enrichment in the middle-inner bays. Metal levels were evaluated in sediments in accordance with the numerical SQG of the USEPA. The levels of fish tissues were lower than the results reported from polluted areas of the Mediterranean. The highest BAFs were detected for Hg and Cd in fish.