Levent Bat

Context: The Black Sea faces continuous anthropogenic pressures, requiring updated baseline data to assess coastal benthic habitat resilience. Aims: This study evaluates the seasonal taxonomic composition, diversity and community structure of soft-bottom macrozoobenthos along the Sinop coasts. Methods: Benthic sampling was conducted at six stations (8–72 m) in May and November 2016 using a 0.1-m2 Van Veen grab. Community structure was analysed using diversity indices and the Turkish benthic index (TUBI). Key results: In total, 101 macrozoobenthic species were identified, including Neanthes acuminata, a new record for the Turkish Black Sea coast. May samples yielded 95 species (2763 individuals, dominated by Mollusca), whereas November yielded 71 species (1619 individuals, dominated by Polychaeta). Key dominant species across seasons included Nereis zonata, Capitella capitata, Lentidium mediterraneum and Amphiura chiajei. Amphibalanus improvisus was the only alien species. Conclusions: The region supports a diverse benthic community with clear seasonal shifts. However, the persistence of the opportunistic polychaete Capitella capitata suggests localised environmental stress. Implications: These findings provide critical baseline data for ecological status monitoring. Continuous tracking is essential to detect biodiversity trends and non-indigenous species arrivals in this changing ecosystem.

In this study, the concentrations of thirteen trace elements (aluminum (Al), arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), manganese (Mn), mercury (Hg), nickel (Ni), selenium (Se), and zinc (Zn)) were determined in the edible muscle tissues of three commonly consumed fish species (Oncorhynchus mykiss, Dicentrarchus labrax, and Sparus aurata). Specimens were obtained from farmed stocks harvested and delivered to fish markets in Sinop, Türkiye, on the day of collection, with sampling carried out on a monthly basis throughout April, May, and June 2024. Zinc and iron exhibited the highest concentrations across all species, while toxic trace elements remained at notably low levels, with Cd (0.005–0.006 mg/kg), Hg (0.015–0.018 mg/kg), and Pb (0.010–0.011 mg/kg) remaining strictly below the European Union maximum permissible limits of 0.05, 0.5, and 0.3 mg/kg, respectively. In addition, a comprehensive human health risk assessment was performed based on a mean daily per capita fish consumption of 19.72 g. The Target Hazard Quotient (THQ) for all evaluated elements and the cumulative Hazard Index (HI), which ranged from 0.0794 to 0.0818 across species, were well below 1.0, indicating negligible non-carcinogenic risk. Carcinogenic risks, evaluated via the Risk Index (RI), were negligible for Cr (1.35–2.35 × 10⁻⁷) and well within acceptable bounds for iAs (2.77–4.13 × 10⁻⁶). The quantitative outcomes of this investigation suggest that under the evaluated conditions, trace element concentrations in these aquaculture products remain within safe baseline levels, contributing meaningful data on food safety and ecological monitoring within the southern Black Sea region.

Echinoderms are one of the major marine invertebrates that can be found on the ocean bottom at each sea profundity from the intertidal zone to the deep zone. There are 5 classes in the phylum Echinodermata (Asteroidea, Ophiuroidea, Echinoidea, Holothuroidea and Crinoidea) even though members of the phylum share a fundamental structure, the biological characteristics of the classes vary greatly. Echinoderm samples comprising Asteroidea, Ophiuroidea, Echinoidea, Holothuroidea and Crinoidea were collected from two unexplored sites Gariyan and Bandari beach along the Jiwani, Makran coast Balochistan. A total of 170 echinoderm specimens were collected during the present study from December 2021 to December 2022. In total, 21 echinoderm species were identified, representing five distinct classes: Holothuroidea (8 species), Asteroidea (7 species), Ophiuroidea (3 species), Crinoidea (2 species) and Echinoidea (1 species). This study significantly expands the documented occurrence and abundance of these taxa along the Makran coast, providing an essential ecological baseline for future biodiversity research and conservation efforts in the region.

Environmental pollution resulting from the rapid increase in human population, urbanization, intensive use of chemicals in agriculture, and industrial development has reached a level that threatens natural life today. Trace elements are one of the most important factors causing significant levels of pollution in the environment and are added to marine ecosystems in high concentrations because of both natural cycles and non‐cycle factors. While essential metals show functional properties by entering the structural composition of living organisms at low concentrations, it is known that non‐essential metals do not have any biological function. Deficiency or high concentrations of metals, which are required in trace amounts by living organisms for vital events, and the effect of toxic metals at low concentrations cause disturbances in metabolic and physiological events, accumulation in tissues and organs, and are transported to higher trophic levels at increasing values through the food chain, ultimately causing significant environmental and health problems. The aim of this study was to determine the concentrations of Al, Cr, Mn, Fe Co, Ni, Cu, Zn, As, Cd, Hg, and Pb in the muscle tissues of Squalus acanthias , Raja clavata , and Dasyatis pastinaca from the southern Black Sea. By focusing on these non‐commercial but ecologically important top predators, the study contributes to the assessment of ecological risks and management strategies for the region.

This study evaluates the accumulation of trace elements (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, Hg, and Pb) in the muscle tissues of six commercially important fish species (Scophthalmus maximus, Merlangius merlangus, Mullus ponticus, Trachurus mediterraneus, Engraulis encrasicolus, and Sprattus sprattus) harvested from multiple locations across the Sinop and Samsun coasts of the southern Black Sea during the 2023–2025 fishing seasons to assess potential human health risks. Element concentrations were quantified using inductively coupled plasma mass spectrometry (ICP-MS) and compared against national and international food safety standards. Results indicated that essential elements, particularly Fe and Zn, exhibited the highest concentrations, while Co and potentially toxic elements (Cd, Pb, As, and Hg) remained at lower levels. Although significant geographical variations in accumulation were observed between sampling locations, inter-species differences were relatively minor. Human health risk assessments, including Estimated Daily Intake (EDI), Target Hazard Quotient (THQ), and Carcinogenic Risk (CR), revealed that all THQ values were well below 1, indicating no non-carcinogenic concerns. Furthermore, CR values for As, Cr, and Pb fell within the acceptable range (10⁻⁶ to 10⁻⁴) defined by the U.S. EPA. Consequently, fish consumption from these regions poses no unacceptable risk, though localized element elevations suggest a need for enhanced environmental monitoring of pollution sources.

This study presents a comprehensive toxicological and dietary risk assessment of potentially toxic and essential trace elements (Cd, Hg, Pb, Cu, Zn, and Fe) in the muscle tissues of European sprat (Sprattus sprattus Linnaeus, 1758) obtained from the local fishermen in Samsun, Black Sea. Element concentrations were quantified using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The mean metal concentrations followed the decreasing order of "Fe">"Zn">"Cu">"Pb">"Hg">"Cd" . All investigated elements were substantially below the maximum permissible limits established by both the European Commission and the Turkish Food Codex, highlighting a clean safety profile. Human health risk assessments were evaluated using the Estimated Daily Intake (EDI), Target Hazard Quotient (THQ), and Total Target Hazard Quotient (TTHQ). The individual THQ values for all elements were well below the critical threshold of 1.0, with the highest risk contribution stemming from mercury (83.3%). The cumulative non-carcinogenic risk index (TTHQ) was exceptionally low 1.34×10-2, indicating that lifetime dietary consumption of S. sprattus from the southern Black Sea poses no chronic health hazards to consumers. These baseline findings highlight the nutritional safety of small pelagic fishes in the region and underscore the importance of continuous bio-monitoring program designs for Black Sea fisheries.

The purpose of the present study was to investigate the levels of toxic (Pb, Hg, Cd) and essential (Cu, Zn) heavy metals in the edible tissues of Chelon auratus (Risso, 1810) purchased from fish markets in Sinop in October, November, and December 2023. In the muscle tissue of the fish, essential metals were found at much higher concentrations than toxic ones. Among the three toxic metals, Pb had the highest concentration, while Cd had the lowest. The concentrations of toxic metals in C. auratus tissues were below the maximum acceptable limits; the target hazard quotient values for Hg, Cd, Cu, and Zn were below 1, and the risk index for Pb was 0.21. In conclusion, the golden grey mullet is considered safe for human consumption.