Combined evaluation of multi-biomarkers and metal bioaccumulations in two different fish species (Sparus aurata and Chelon labrosus) from Izmir Bay, Türkiye (Aegean Sea): Spatial, temporal and tissue-specific approaches.

Biomarkers were investigated to assess the effects of metal accumulation in Sparus aurata and Chelon labrosus in the Izmir Bay. Fish were collected from the Inner and Outer Bays in November 2020 and May 2021. According to the metal and biomarker measurements found in the organs, it was observed that the levels were higher in the liver and gill tissues than in the muscle tissues. Significant differences between tissues were found for all metals and biomarkers. In addition, biochemical biomarkers were found to be significant predictors of metal bioaccumulation. Histological changes were observed in liver and gills in each species and location. Although the metal levels determined according to the health risk assessment were below the threshold limits, the As levels for the lifetime cancer risk were within the limits to be considered. In conclusion, this study will provide robust results for its related study area.

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.

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.

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.

Distribution of aliphatic and aromatic hydrocarbons in red mullet (Mullus barbatus) and annular sea bream (Diplodus annularis) from the Izmir Bay (eastern Aegean).

Polycyclic aromatic and aliphatic hydrocarbons were analyzed in red mullet and annular sea bream from the Izmir Bay. These fishes were selected because of their multitude, wide distribution and common use in the Turkish diet; they were sampled and analyzed in 2000-2001 and 2004-2005 periods at five locations by trawling. Red mullet showed higher PAHs and aliphatics than annular sea bream. PAH levels for red mullet and annular sea bream ranged from 202 to 556 and 78.7 to 415; aliphatics ranged from 834 to 2,420 and 436 to 1,724 ng/g dw, respectively. Molecular ratios showed pyrolitic inputs for PAHs, biogenic and anthropogenic inputs for aliphatics. The carcinogenic PAH, benzo(a)pyrene, was detected in most fish samples in levels ranged between 22.2 and 64.1 ng/g dw. The average PAH contamination level was within the "moderate" category in fish from Izmir Bay. Results indicate the needing of a systematic monitoring program in order to provide accurately assessment and management of risks for the regional population.