Commercial Fisheries Research Articles

Some features of natural spawning and problems of artificial reproduction of the cherry salmon Oncorhynchus masou (Brevoort, 1856)

The article discusses certain aspects of the dispersal and biology of cherry salmon, Oncorhynchus masou (Brevoort, 1856). It is noted that the species is the southernmost within the Pacific Salmon family and is also the only member of the Oncorhynchus genus whose habitat is exclusively in Asia. The decline in the number of cherry salmon across their range has been highlighted, and the main underlying factors have been identified. Some features of cherry salmon spawning run in various parts of their range are examined. A long stay of spawners in fresh water before spawning with preservation of feeding behavior is noted, which makes the species an extremely compelling object of recreational and commercial fishing. Some features of natural reproduction, such as spawning timing and fertility, depending on the habitat and size of the spawners, are indicated. The issue of preserving and restoring the species population is touched upon; the most appropriate method of its implementation is the artificial reproduction of the young with subsequent release into the natural habitat. The paper highlights a number of obstacles to the implementation of such programs, such as the undeveloped technology for growing young masu salmon and the difficulty of optimizing the temperature regime at hatcheries. As one of the limitations to increasing release volumes, it is indicated that masu salmon belongs to a species that have a long freshwater period, with the young spending up to three years in the river. A large number of juvenile masu salmon in the river leads to insufficient food supply and high mortality. In order to overcome this factor, it has been proposed to conduct research aimed at stimulating the smoltification of hatchery salmon fingerlings. This measure will allow significantly increasing the number of smolt and the return rates of spawners, which can be removed without affecting the natural populations.

Real-world waste dispersion modelling for benthic integrated multi-trophic aquaculture.

In real-world situations, marine fish farms accommodate multiple fish species and cohorts within the farm, leading to diverse farm layouts influenced by cage dimensions, configurations, and intricate arrangements. These cage management practices are essential to meet production demands, however, farm-level complexities can impact model predictions of waste deposition and benthic impact near fish cages. This is of particular importance when the cages are used for integrated multi-trophic aquaculture (IMTA) with benthic feeders, where this waste not only affects environmental conditions but also provides a potential food source. The Cage Aquaculture Particulate Output and Transport (CAPOT) model incorporated multiple species, cohorts, and cage arrangements to estimate waste distribution from a commercial fish farm in the Mediterranean between October 2018 and July 2019. This spreadsheet model estimated dispersion for individual fish cages using a grid resolution of 5 m x 5 m. The study categorized discrete production periods for each fish cage every month, aligning with intermittent changes in biomass and food inputs due to different cage management practices throughout production. This approach facilitated the use of detailed input data and enhanced model representativeness by considering variations in cage biomass, food types, settling velocities, and configurations. Model outputs, represented in contour plots, indicated higher deposition directly below fish cages that varied monthly throughout fish production cycles. Deposition footprints reflected changes in cage biomass, food inputs, and farm-level practices reflecting this real-world scenario where aquaculture does not follow a production continuum. Moreover, cohort dynamics and cage movements associated with the cage management practices of the fish farm influenced the quantity and fate of wastes distributed around fish cages, revealing variability in deposition footprints. Clearly, these findings have important implications for the design of benthic IMTA systems, with species such as sea cucumber and polychaetes. Variability in waste deposition creates challenges in identifying where the benthic organisms should be placed to allow optimal uptake of waste to meet their food requirements and increase survivability. Evidently, models have an important role to play and this study emphasizes the need for representative input data to describe actual food inputs, cage biomass changes, and management practices for more representative farm-scale modelling and essentially to improve particulate waste management. To effectively mitigate benthic impacts through IMTA, models must quantify and resolve particulate waste distribution and impact around fish farms to maintain a balanced system with net removal of wastes. Resolving farm-level complexities provides vital information about the variability of food availability and quality for extractive organisms that helps improve recycling of organic wastes in integrated systems, demanding a more representative modelling approach.

DNA Barcoding Revealed a High Percentage of Mislabeling in Commercial Fish Products: The First Empirical Survey in South Texas

Seafood mislabeling is a widespread problem that have produced a growing distrust of seafood industry. In this study, we examined the prevalence of mislabeling in fish samples from regional markets in the greater Houston area and close-by coastal communities. A total of 63 fish fillet samples were purchased, labeled, and stored at -20˚C in individual packages until DNA extraction. DNA fragments of roughly 700 base pairs encoding cytochrome oxidase I (COI) were PCR-amplified from each DNA sample. With 99.6–100% nucleotide identity in the GenBank and BOLD databases, all samples were correctly identified at the species level. The scientific names identified by DNA barcoding were matched with legally acceptable market names using the US Food and Drug Administration (FDA) Seafood List. Out of the 63 samples examined, 13 samples (20.6%) were mislabeled. Moreover, 24 samples (38.1%) did not use the acceptable market names, indicating that the FDA policy is poorly implemented in seafood industry. The first DNA barcoding survey this area warranted the need of continuous monitoring and the dissemination of the regulation combined with taxonomic knowledge.

Marine protected areas and fishing community well-being: An example from statewide socioeconomic monitoring of the California MPA network

As marine protected areas (MPAs) continue to proliferate as an ocean conservation tool, it is important to understand their socioeconomic outcomes, both in the short-term following implementation and in the long-term as they become a more permanent part of the ocean landscape. This paper presents results from an effort to conduct long-term socioeconomic monitoring of commercial fishing communities in relation to California's statewide MPA network, which was fully implemented in 2012 and consists of 124 MPAs covering 16% of state waters. To assess commercial fishing community perceptions of well-being and outcomes from the MPA network, we held virtual focus groups in 18 major port-based commercial fishing communities across California with a total of 85 participants from 2020 to 2021. Focus groups had both quantitative and qualitative components, with participants rating their fishing community and engaging in discussions on topics related to their environmental, economic, and social well-being and MPA outcomes. Results revealed that perceptions of fishing community well-being varied throughout the state, but were overall low. Key areas for improvement included recruitment and retention of participants in the fishing industry, availability and maintenance of key fishing infrastructure, and access to harvestable resources. Fishing community perceptions of the management and outcomes from the MPA network were overwhelmingly low across the state with little variation. Common reasons for participant dissatisfaction included perceptions of negative ecological and livelihood outcomes from the MPAs and a perceived lack of clear MPA management goals in addition to poor communication of those goals. Overall findings highlight the value of collecting community well-being data in coordination with long-term socioeconomic MPA monitoring to understand the greater context in which MPAs are received. A well-being approach to socioeconomic MPA monitoring also broadens policy pathways that could help improve outcomes from and beyond MPAs to support overall fishing community health.

Evaluating the unexplored recreational fishing in the Turkish Black Sea: socio-economic significance and environmental impact

Marine recreational fishing, a globally popular outdoor activity, has deep cultural roots and ecological implications. This study, conducted between 2021-2022, explores marine recreational fishing practices along the Turkish Black Sea coast. It analyzes fisher numbers and demographics, fishing effort, fishing methods, and species caught and released. Furthermore, the research sheds light on the economic dimensions, emphasizing the substantial contributions of recreational fishing to local economies. Notably, responsible practices, such as catch-and-release initiatives, demonstrate anglers’ awareness of conservation efforts. Within the Turkish Black Sea region, an observed 18.5% participation rate among a population of 24.5 million implies the presence of approximately 4.5 million marine recreational fishers. Annually, this translates to nearly 30 million fishing days, accompanied by a total expenditure of 400 million Euros. However, it’s imperative to handle these figures cautiously as the timing of the screening survey during the COVID-19 pandemic may have influenced the high participation rate, introducing a potential bias. A detailed examination of a Turkish marine recreational fisher engaged in Black Sea fishing reveals an average annual catch of 16.5 kg of retained fish and 1.2 kg of released fish biomass. When extrapolated to the larger population of 4.5 million fishers, this culminates in a noteworthy landing biomass approaching 74,000 tons. The study unveils that marine recreational fishers in the Turkish Black Sea predominantly target commercially important species, resulting in a retained biomass surpassing commercial landings in 2021. This prompts concerns about potential impacts on crucial commercial fish stocks, underscoring the imperative inclusion of recreational fisheries in stock assessments. The research, providing essential insights into the intricate dynamics of recreational fishing, lays a foundation for well-informed policies and practices that concurrently promote environmental conservation and the continuation of this valued leisure activity.

Recreational fisheries selectively capture and harvest large predators

AbstractSize‐ and species‐selective harvest inevitably alters the composition of targeted populations and communities. This can potentially harm fish stocks, ecosystem functionality, and related services, as evidenced in numerous commercial fisheries. The high popularity of rod‐and‐reel recreational fishing, practiced by hundreds of millions globally, raises concerns about similar deteriorating effects. Despite its prevalence, the species and size selectivity of recreational fisheries remain largely unquantified due to a lack of combined catch data and fisheries‐independent surveys. This study addresses this gap by using standardised monitoring data and over 60,000 digital angling catch reports from 62 distinct fisheries. The findings demonstrate a pronounced selectivity in recreational fisheries, targeting top predators and large individuals. Catch‐and‐release practices reduced the overall harvest by 60% but did not substantially alter this selectivity. The strong species‐ and size‐specific selectivity mirror patterns observed in other fisheries, emphasising the importance of managing the potential adverse effects of recreational fisheries selective mortality and overfishing.

At-sea distribution of marine predators around South Georgia during austral winter, with implications for fisheries management

The sub-Antarctic island of South Georgia is surrounded by highly productive waters, supporting dense aggregations of Antarctic krill (Euphausia superba), a vital food source for globally important seabird and marine mammal populations. These waters also support a commercial fishery for Antarctic krill. Regular monitoring of key krill predator species is undertaken at South Georgia to detect any changes in the ecosystem in response to harvesting activities. This monitoring provides essential data but is focused on land-breeding animals during the austral summer, whilst the krill fishery operates exclusively in winter. Here, we report the results of at-sea surveys to investigate abundance and distribution of krill-dependent predators from winter 2010 and 2011, which represented a “poor” krill year and “good” krill year, respectively. Correspondingly in 2011 higher numbers of krill predators were observed; notably Antarctic fur seals (Arctocephalus gazella) across the northern shelf. Spatial overlap between fur seals and the krill fishery occurred mainly within the krill fishery hotspot to the north-east, highlighting the potential for locally high levels of competition. Cetaceans were observed during both survey years, but in low numbers compared to recent studies. Gentoo penguins (Pygoscelis papua) were the most frequently observed penguin species, showing an inshore distribution and almost no overlap with the krill fishery. Diving-petrels (Pelecanoides spp.) were the most abundant flying seabirds, observed across all transects, with particularly high densities to the south in early winter 2010. In conclusion, this survey provides valuable baseline data on the distribution of South Georgia’s predators during the winter months.

Vertebral chemistry distinguishes regional populations of Blacktip Sharks in the northern Gulf of Mexico

AbstractObjectiveUnderstanding the spatial connectivity of elasmobranch populations is critical for regional fisheries management. The Blacktip Shark Carcharhinus limbatus is abundant in coastal waters of the Gulf of Mexico (GoM) and important in recreational and commercial fisheries. Based on genetic and tagging studies, GoM Blacktip Sharks are currently managed under separate quotas between the eastern and western GoM (divided at 88°W), but no studies have used vertebral chemistry to assess the population structure of adult Blacktip Sharks.MethodsWe compared vertebral elemental signatures (barium [Ba], magnesium [Mg], manganese [Mn], strontium [Sr], and zinc [Zn]) for the first year of life with last occupied habitats (vertebral edges) in Blacktip Sharks collected from the western (Texas and Louisiana) and eastern (Alabama and Florida) coastal waters of the northern GoM.ResultWe found significant regional differences in Ba, Mg, Mn, and Sr vertebral edge signatures, suggesting ecological separation of Blacktip Sharks. Significant correlation between first‐year and edge signatures suggested a high degree of residency between life stages. Cross‐validated discriminant function analyses yielded highest regional classification accuracies when Florida sharks were grouped separately west of 88°W (90%), demonstrating the unique elemental signatures of eastern versus western GoM Blacktip Sharks under current management delineations.ConclusionCombined, these findings demonstrate that trace element markers can distinguish regional populations of Blacktip Sharks and provide a complimentary approach in addition to genetics and physical tagging to support current stock management efforts.

Horizon scan survey to identify key research questions to promote sustainability of the marine recreational fishery in Namibia

Horizon scan survey to identify key research questions to promote sustainability of the marine recreational fishery in Namibia

Cyanotoxins bioaccumulation by fish in an anthropized reservoir in central Mexico

The bioaccumulation of cyanotoxins has been well documented in exposed organisms including fish, which represent a potential route to cyanotoxins transfer to humans by consumption of contaminated food. We determined the bioaccumulation of neurotoxic saxitoxins and hepatotoxic microcystins in muscle and liver/viscera of native (Goodea atripinnis), introduced (Poeciliopsis gracilis), and commercially important (Oreochromis niloticus) fish in Santa Catarina, an anthropized reservoir in Central Mexico. Additionally, we calculated the potential risk of human exposure due to the consumption of the studied species. The Santa Catarina Reservoir showed some physical and chemical water parameters generally associated with cyanobacterial blooms (e.g., high phycocyanin, chlorophyll-a, dissolved phosphorus concentrations, and alkaline pH) with presence of cyanotoxins produced by the cyanobacteria genera Microcystis, Dolichospermum, and Planktothrix, which were found in dissolved and particulate (sestonic) fractions of water. Moreover, we detected the presence of saxitoxins and microcystins in the tissues of all species studied. The risk of intoxication for humans was lower for the consumption of Nile tilapia muscle than for the other analyzed species, whose consumption should be avoided since it exceeds the recommended daily intake of microcystins for a short-term (i.e., two-week exposure time). These findings are remarkable because commercial fishing in reservoirs and the consumption of these fish could represent a route to human exposure to toxins, particularly microcystins. Our results highlight the need for the detection of cyanotoxins and the evaluation of their bioaccumulation by fish in unstudied eutrophic waterbodies, to reduce the potential health risk for humans and the environment.

Review of: "Review of: Estimates of Atlantic Goliath Grouper (Epinephelus Itajara) Bycatch Mortality in Commercial Fisheries of the Southeastern Us From 2002 to 2022"

Review of: "Review of: Estimates of Atlantic Goliath Grouper (Epinephelus Itajara) Bycatch Mortality in Commercial Fisheries of the Southeastern Us From 2002 to 2022"

Excessive Eutrophication as a Chemical Barrier for Fish Fauna Dispersion: A Case Study in the Emblematic Tietê River (São Paulo, Brazil)

The Tietê River receives most of the effluents and diffuse wastes from the São Paulo metropolis (21.9 million inhabitants). The study aimed to assess the extent to which environmental changes affected the fish fauna. We compared, in rainy and dry seasons, three sites in Tietê and three in tributaries with much better water quality conditions. No physical barriers exist between the sites. Fish were sampled with gillnets (exposed overnight) and the assemblage’s ecological attributes calculated. Water depth, transparency, temperature, electrical conductivity, dissolved oxygen, turbidity, total dissolved solids, pH, redox potential, total phosphorus, total nitrogen, and chlorophyll were simultaneously determined. Low oxygen concentrations (near zero in the rainy period), and the opposite for nutrients and total solids, separated the predominantly hypereutrophic Tietê from the tributaries (PCA). Differences in the fish assemblages were also evidenced (nMDS), including a higher richness per sample in tributaries (11 to 14 spp.) compared to Tietê (3 to 4 spp.). Siluriformes with accessory breathing dominated in Tietê and the highly tolerant detritivorous Prochilodus lineatus (the main commercial fish) was the only species found in all sites. The species correlated positively with oxygen in the tributaries and with turbidity, redox potential, and nutrients in Tietê (DistLM) (rainy season). Recovery measures are urgently required.

Calibration of commercial fisheries echo sounders using seabed backscatter for the estimation of fishery resources.

Acoustic methods are often used for fisheries resource surveys to investigate fish stocks in a wide area. Commercial fisheries echo sounders, which are installed on most small fishing vessels, are used to record a large amount of data during fishing trips. Therefore, it can be used to collect the basic information necessary for stock assessment for a wide area and frequently. To carry out the quantification for the fisheries echo sounder, we devised a simple method using the backscattering strength of the seabed to perform calibration periodically and easily. In this study, seabed secondary reflections were used instead of primary reflection because the fisheries echo sounders were not equipped with a time-varied gain (TVG) function, and the primary backscattering strength of the seabed was saturated. It was also necessary to use standard values of seabed backscattering strength averaged over a certain area for calibration to eliminate some of the effects of differences in seabed sediment and vessel motions. By using standard values of the seabed secondary reflections, the fisheries echo sounder was calibrated accurately. Our study can provide a reliable framework to calibrate commercial fisheries echo sounders, to improve the estimation and management of fishery resources.

¬Occurrence of Microplastic Ingestion by Commercial Fish Species from the Pangempang Estuary in Indonesia

The aim of this study was to assess the occurrence of microplastic in digestive organs (esophagus to intestine) of popular marine commercial fish species: Jack (Caranx SP.), blackspot snapper (Lutjanus fulviflamma), coral grouper (Epinephelus carallicala), golden snapper (Lutjanus johnii) and pickhandle barracuda (Sphyraena jello) from Pangempang Estuary in Indonesia. To separate the microplastic particles, each sample was digested using alkaline digestion solution, filtered on Whatman paper and then dried. Microplastic particles in the processed digestive organ contents were identified and enumerated using a dissecting stereo microscope. Microplastics were observed in 94 % of fish digestive organs sampled: 100 % jacks (n = 10), 80 % blackspot snapper (n = 10), 100 % coral grouper (n = 10), 90 % golden snapper (n = 10) and 100 % pickhandle barracuda (n = 10). In these fish samples we found in average of 41 ± 6.0, 26 ± 11.0, 15 ± 2.0, 11 ± 1.0 and 14 ± 2.0 SE microplastic particles per individual and an average of 499.5 ± 94.4, 501.5 ± 198.8, 83.6 ± 18.4, 79.8 ± 11.6 and 40.2 ± 25.0 SE microplastic particles per kg fish weight, in jacks, blackspot snapper, coral grouper, golden snapper and pickhandle barracuda, respectively. Fiber was the most dominant type accounting for 78.6 % of all observed microplastics. Microplastic beads were not detected. The correlation of the average consumed microplastic and the average fish weight per species showed a negative relationship (R2 = 0.36), but was not significant (p-value = 0.28). Our finding suggests that demersal fish like jacks, blackspot snapper and coral grouper may have ingested a higher quantity of microplastic particles compared to pelagic species like pickhandle barracuda. HIGHLIGHTS This study demonstrates the presence of microplastic particles in 5 commercially important fish in a tropical estuary of Kalimantan Island in Indonesia Fiber was the most dominant type of microplastic Demersal fish may have ingested a higher quantity of microplastic particles compared to pelagic species GRAPHICAL ABSTRACT

Rapid on-site authentication of three cockle species using real-time loop-mediated isothermal amplification (LAMP) assay

Cockles, crucial for commercial fishing and aquaculture, emerge as highly marketable shellfish. However, the morphological similarities among various cockle species are frequently exploited for shellfish fraud. In this study, we developed LAMP assays (end-point LAMP and real-time LAMP) to detect three commercially important cockle species: Tegillarca granosa, Anadara broughtonii, and Anadara kagoshimensis. The primers were designed based on mitochondrial DNA and used to develop LAMP assays. Exclusivity was assessed using 17 shellfish species, and no cross-reactivity was confirmed. The estimate of the detection limit was determined to be 0.0001 ng. The established assays were further refined to create an on-site real-time LAMP assay by combining fast DNA isolation with a real-time fluorometer for field application. The effectiveness of the on-site real-time LAMP assay was successfully verified using 38 commercial samples, with analysis accuracy confirmed using a DNA extraction kit. Consequently, the on-site real-time LAMP assay can complete the whole procedure, including DNA extraction, real-time LAMP reaction, and data analysis within a 45 min timeframe, maintaining the accuracy of detecting three cockle species from processed cockle samples in the field. Our method proves valuable for detecting shellfish fraud by identifying cockle species using samples of both raw and processed products in the field.

Long-distance migrations and seasonal movements of meagre (Argyrosomus regius), a large coastal predator, along the Iberian Peninsula coast

BackgroundThe meagre, Argyrosomus regius, is a large coastal predatory fish inhabiting waters from the north-eastern Atlantic and Mediterranean Sea, where it is targeted by commercial and recreational fisheries. Previous genetic studies have found an unexpectedly high population differentiation not only between the Atlantic and the Mediterranean, but also along the Atlantic coast. However, the reasons underpinning this genetic barrier remained unclear. Likewise, even though the species is amongst the world’s largest marine teleosts, knowledge about its movement ecology and migratory behaviour remains notably scarce, and primarily reliant on fisheries-dependent data.MethodsIn this study, we used a combination of acoustic telemetry and pop-up satellite archival tags to investigate the movements of 22 adult meagre (70–143 cm total length) along the Southwestern coast of the Iberian Peninsula.ResultsOur results strongly suggest that the previously reported genetic differentiation is not maintained by limited adult dispersal/movement, as hypothesized. On the contrary, we documented some of the longest individual annual migrations ever recorded for a coastal teleost, up to > 2000 km, with frequent back-and-forth movements between the West and Southern Iberian coasts. Moreover, their detected regional movement patterns support the existence of a marked seasonal behavioural shift, with individuals being less active and moving to deeper waters during winter, and are consistent with spawning philopatry associated to their summer reproductive movements. Finally, we identified putative aggregation areas that may harbour important feeding/overwintering grounds.ConclusionsThese findings shed new light on the movement and behaviour patterns of meagre that may be of particular importance for the conservation and spatial management of this species throughout its range, and open the door to further research on functional connectivity.

Coexisting in the Surf Zone: Age and Feeding Habits of the Spotted Seabass (Dicentrarchus punctatus) and European Seabass (Dicentrarchus labrax) on the Gulf of Cádiz Beaches (Southwest Iberian Peninsula)

Various commercial fish species utilize different coastal habitats as nurseries in their juvenile stages, with surf zones being particularly crucial due to the protection and abundant food resources they offer. Among the species that rely on these areas are the spotted seabass (Dicentrarchus punctatus) and the European seabass (Dicentrarchus labrax). This study aimed to investigate the age and feeding habits of surf zone specimens of these species and explore their environmental adaptations. The average size for D. punctatus was 16.94 ± 4.05 cm, and for D. labrax, it was 23.23 ± 6.30 cm. The length–weight relationship for D. punctatus was TW = 0.013*TL2.885 (parameter a: 95% CI: 0.012–0.014; parameter b: 95% CI: 2.854–2.917), and for D. labrax, it was TW = 0.008*TL3.095 (parameter a: 95% CI: 0.006–0.009; parameter b: 95% CI: 3.040–3.151). In both D. punctatus (79.20%) and D. labrax (75.92%), the predominant age classes were 1+ and 2+. Significant variations in age class abundance were observed in D. punctatus based on the time of day, lunar phase, and season, while D. labrax showed variations only by season. A diet analysis revealed that both species primarily consume mysids and fish, with D. punctatus showing dietary variations related to the time of day, lunar phase, and season, and D. labrax showing variations with the time of day and season.

Economic trade-offs of harvesting the ocean twilight zone: An ecosystem services approach

The mesopelagic or ocean twilight zone (OTZ) in the ocean contains huge numbers of fish in a relatively pristine environment and may therefore attract interest as a commercial fishery. In this study we evaluate in economic terms, the likely trade-offs between the different services provided by the mesopelagic layer in the Bay of Biscay and the societal benefits of its commercial exploitation. Benefits arise mainly from the likely use of this group of species as raw material for producing fishmeal and fish oil. Costs are derived from the loss in climate regulating and cultural, services, but also from the loss in the provisioning service of other commercial species. To do so we compare the current non-exploited status with a situation in where mesopelagic fishes are harvested at levels capable of producing the Maximum Sustainable Yield. Results suggest that if mesopelagic fishes are harvested, a mean value of 1.2 million Euro loss in a year will be created in the Bay of Biscay, although in a range between 42 million Euro loss and 48 Euro million benefits. This uncertainty comes, mainly, from the limited existing knowledge of the mesopelagic fishes’ biomass but also from the uncertainty on the biomass of the rest of the species of the studied ecosystem. The large range indicates that a better understanding of the mesopelagic ecosystem is needed, however, results also show that ecosystem services under no exploitation provided by the OTZ could be more valuable than the fishmeal and fish oil that potentially could be obtained from the fishes harvested in this sea layer.

An extensive investigation on human risk associated with PAHs in fish and sediment in Bushehr, Northern of Persian Gulf

Here, a comprehensive study was designed to estimate the human risk assessment attributed to exposure of polycyclic aromatic hydrocarbons (PAHs)in sediment and fish in most polluted shore area in north of Persian Gulf. To this end, a total of 20 sediment and inhabitual Fish, as one of most commercial fish, samples were randomly collected from 20 different stations along Bushehr Province coastline. The 16 different components of PAHs were extracted from sediment and edible parts of inhabitual fish and measured with high-performance liquid chromatography (HPLC) and gas chromatography (GC), respectively. In addition, dietary daily intake (DDI) values of PAHs via ingestion Indian halibut and the incremental lifetime cancer risk (ILCR) attributed to human exposure to sediments PAHs via (a) inhalation, (b) ingestion, and (c) dermal contact for two groups of ages: children (1–11 years) and adults (18–70 years) were estimated. The results indicated that all individual PAHs except for Benzo(b)flouranthene (BbF) and Benzo(ghi) perylene (BgP) were detected in different sediment sample throughout the study area with average concentration between 2.275 ± 4.993 mg.kg–1 dw. Furthermore, Naphthalene (Nap) with highest average concentration of 3.906 ± 3.039 mg.kg–1 dw was measured at the Indian halibut. In addition, the human risk analysis indicated that excess cancer risk (ECR) attributed to PAHs in sediment and fish in Asaluyeh with high industrial activities on oil and derivatives were higher the value recommended by USEPA (10−6). Therefore, a comprehensive analysis on spatial distribution and human risk assessment of PAHs in sediment and fish can improve the awareness on environmental threat in order to aid authorities and decision maker to find a sustainable solution.

Evaluation of heavy metal accumulation and associated human health risks in three commercial marine fish species from the Aegean Sea, Türkiye

This study investigates the presence and concentrations of ten specific heavy metals in the muscle tissues and gonads of three commercially important marine fish species: Garfish (Belone belone), European barracuda (Sphyraena sphyraena), and Anglerfish (Lophius piscatorius) collected from the Aegean Sea in Türkiye. The results indicate variations in metal accumulation, both between genders and among species. The fish species tend to accumulate higher levels of heavy metals in their gonads than in muscle tissues (p<0.05). While Cr, Cd, and Pb were not detected, Zn, Cu, and Fe are the predominant metals in muscle tissues due to their essential biological roles. However, within toxic elements, Hg was predominant, and L. piscatorius, a benthic fish, exceeded its recommended safety limits. A health risk assessment suggests that except for L. piscatorius, consuming these fish species from the Aegean Sea is generally safe, with estimated weekly intake (EWI) values below permissible limits. Total Hazard Quotient (THQ) values for most metals are below 1, indicating no significant non-carcinogenic health risks for consumers. This study emphasizes the critical need for regularly monitoring heavy metal levels in marine fish from the Aegean Sea, Turkiye. While overall safety in consuming these fish is highlighted, exceptions exist, notably concerning Hg levels in L. piscatorius. Therefore, persistent monitoring of heavy metal concentrations, especially in L. piscatorius, is advised to ensure ongoing safety and mitigate potential risks of metal accumulation.