Assessing chemical contamination in the coastal waters of the Adriatic Sea using active mussel biomonitoring with Mytilus galloprovincialis

A novel approach to assess temporal baseline levels of trace metal contamination in the mussel M. galloprovincialis in the Mediterranean, Marmara and Black Seas

This study reports, for the first time, the baseline levels for fifteen trace metals in M. galloprovincialis tissue from around the Mediterranean, Marmara and Black Seas. The environmental quality in the surrounding seawater was assessed i.e., a mussel farm was investigated by using CF and DC indices, and the water quality was qualified as good for the aquacultural activities. A strong Cu-regulation in the transplanted mussels was observed and it ranged between 3.20 and 3.60 μg/g d.w. The highest bioavailability and bioconcentration of the particulate Fe fraction could present a health risk to consumers with a low risk level (1 < THQ < 9.9). Cr is considered the limiting metal for mussel consumption (< 2 kg/day). The metal contamination gradient was assessed using TEPI and TESVI indices that identified seven reference stations on the large scale and revealed that Cd is the most investigated metal in the literature databases, and found that Pb was the most bioavailable contaminant in the areas examined.

Polychlorinated biphenyls in mussels, small pelagic fish, tuna, turtles, and dolphins from the Croatian Adriatic Sea waters: an overview of the last two decades of monitoring

This review summarises our two decades of polychlorinated biphenyl (PCB) monitoring in different marine organisms along the eastern Adriatic Sea. The aim was to gain an insight into the trends of PCB distribution in order to evaluate the effectiveness of past and current legislation and suggest further action. Here we mainly focus on PCB levels in wild and farmed Mediterranean mussels, wild and farmed bluefin tuna, loggerhead sea turtles, common bottlenose dolphins, and small pelagic fish. The use of artificial intelligence and advanced statistics enabled an insight into the influence of various variables on the uptake of PCBs in the investigated organisms as well as into their mutual dependence. Our findings suggest that PCBs in small pelagic fish and mussels reflect global pollution and that high levels in dolphins and wild tuna tissues raise particular concern, as they confirm their biomagnification up the food chain. Therefore, the ongoing PCB monitoring should focus on predatory species in particular to help us better understand PCB contamination in marine ecosystems in our efforts to protect the environment and human health.

Trace Metals in the Mussel Mytilus californianus from the West Coast of Baja California, Mexico

This study assessed the concentrations of trace metals in tissues of Mytilus californianus from the west coast of Baja California, Mexico, during the cold and warm seasons. The concentrations of silver, cadmium, copper and zinc in mussel tissues were measured using Atomic Absorption Spectrophotometry. Silver concentrations ranged from 0.03 to 0.48 µg/g dry weight (d.w.) with significantly higher values registered at sites close to densely populated areas. Cadmium, copper, and zinc concentrations ranged from 0.57 to 7.83 µg/g d.w., 3.71 to 621 µg/g d.w., and 57.54 to 124.55 µg/g d.w., respectively. According to the WHO, values of copper and zinc were within acceptable limits. The maximum values of cadmium, however, exceeded the recommended limits set by the European Commission (2014). The human health risk of the metals analyzed was low (THQ and HI < 1). The regular monitoring of trace metals in M. californianus is recommended for a more definitive evaluation of contaminants.

Untargeted Metabolomics Analyses and Contaminant Chemistry of Dreissenid Mussels at the Maumee River Area of Concern in the Great Lakes

Bivalves serve as an ideal ecological indicator; hence, their use by the NOAA Mussel Watch Program to monitor environmental health. This study aimed to expand the baseline knowledge of using metabolic end points in environmental monitoring by investigating the dreissenid mussel metabolome in the field. Dreissenids were caged at four locations along the Maumee River for 30 days. The mussel metabolome was measured using nuclear magnetic resonance spectroscopy, and mussel tissue chemical contaminants were analyzed using gas or liquid chromatography coupled with mass spectrometry. All Maumee River sites had a distinct mussel metabolome compared to the reference site and revealed changes in the energy metabolism and amino acids. Data also highlighted the importance of considering seasonality or handling effects on the metabolome at the time of sampling. The furthest upstream site presented a specific mussel tissue chemical signature of pesticides (atrazine and metolachlor), while a downstream site, located at Toledo's wastewater treatment plant, was characterized by polycyclic aromatic hydrocarbons and other organic contaminants. Further research into the dreissenid mussel's natural metabolic cycle and metabolic response to specific anthropogenic stressors is necessary before successful implementation of metabolomics in a biomonitoring program.

Environmental organic contaminant body burdens and GC-MS based untargeted metabolomics in mediterranean mussels from Port Phillip Bay, Australia☆

Mussels were collected from four coastal sites around Port Phillip Bay, Australia in Mar and Apr 2021). Body burdens of Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were measured and the possible sources of toxicants discussed. In addition, a gas chromatography-mass spectrometry (GC-MS) based untargeted metabolomics analysis was performed using the mantle tissues of mussels. Correlations between the results of contaminant body burdens and metabolic variations were investigated. The results demonstrated that high accumulations of low-molecular-weight PAHs were found in mussels. High body burdens of PCBs and OCPs were only found at mussels from the site close to the river mouth. Some of the metabolic pathways were correlated with the accumulation of PAHs. No correlations were found between PCB and OCP accumulations and metabolic abundances. According to the food and environmental standards of the European Union (EU), the PAH, PCB, and OCP accumulation in mussels in this study are a serious food safety concern.

Elements in Soft Tissues of the Young Mediterranean Mussel Mytilus galloprovincialis Lam. 1819 Collected in Sevastopol Bay (Crimea, Black Sea): Effects of Age, Sex, Location, and Principal Morphometric Parameters

Although the mussel Mytilus galloprovincialis has been known for decades as an excellent bioindicator of trace element pollution in the marine environment, there is still no information on the effects of a suite of its principal morphometric parameters and age on trace element levels in soft tissues. In this work, using inductively coupled plasma mass spectrometry, we studied the contents of 72 elements in soft tissues of M. galloprovincialis aged 0.5-4, which were sampled at three stations within a relatively small water body, Sevastopol Bay. Significant effects of age and sampling location on the element contents and soft tissue dry-to-wet weight ratio were discovered. The effects of sex were not significant. It was presumed for the first time that the decrease in element content in the soft tissues of young mussels can be associated with the decrease in physiological needs for elevated contents of essential elements and intracellular water with age. Combinations of six principal morphometric parameters showed that a function of as few as three parameters (soft tissue dry weight, whole mollusk weight, and shell height, with by far the greatest contribution of the dry-to-total weight ratio) formed significant correlations with the contents of the largest possible number of elements (69-88% of the total number). For the first time, it was shown that linear discriminant analysis and canonical analysis of principal coordinates can be successfully used for tracing the exact origin of mussel samples within such a small water area. Canonical analysis of principal coordinates proved superior in the correct classification of the samples.

Effect of in-house cooking in Mytilus galloprovincialis and Trachurus trachurus: Lipid and fatty acids quality and polycyclic aromatic hydrocarbons formation

Cooking effect (grilling - barbecue, oven-cooking, frying, boiling and microwaving) on lipid and fatty acids (FAs) in mussel Mytilus galloprovincialis and fish Trachurus trachurus was investigated. The levels of priority PAHs were also evaluated as well as the potential risk associated with their consumption. Cooking increased lipid content, reaching the highest value in fried product with 13.2 and 5.6 g/100 g in mussel and fish, respectively. The n-3/n-6 ranged from 0.15 to 5.31 in mussel and from 0.29 to 5.35 in mackerel. In both species, frying and oven-cooking negatively affected FAs composition as shown by the lipid quality indices. However, FAs profile exhibited by species after cooking remained beneficial for human health. Concerning PAHs, levels ranged from 31 to 78 μg/kg in M. galloprovincialis, and from 8.4 to 25 μg/kg in T. trachurus. The minimum and maximum values were found, respectively, in the raw product and after barbecue cooking with charcoal placed at 4 cm away from the seafood. The carcinogenic benzo[a]pyrene was detected only in mussels after barbecue cooking. Risk assessment of dietary exposure to PAHs, calculated by the Hazard Quotient and Cancer Risk, showed that the consumption of cooked seafood should not be a concern for human health.

Single and combined potential of polystyrene microparticles and fluoranthene in the induction of DNA damage in haemocytes of Mediterranean mussel (Mytilus galloprovincialis)

In this study, the possible 'vector effect' within the exposure of Mediterranean mussels (Mytilus galloprovincialis) to polystyrene microplastics with adsorbed fluoranthene was investigated by applying the multibiomarker approach. The major focus was placed on genotoxicological endpoints as to our knowledge there are no literature data on the genotoxicity of polystyrene microparticles alone or with adsorbed fluoranthene in the selected experimental organisms. DNA damage was assessed in haemocytes by comet assay and micronucleus test. For the assessment of neurotoxicity, acetylcholinesterase activity was measured in gills. Glutathione S-transferase was assessed in gills and hepatopancreas since these enzymes are induced for biotransformation and excretion of lipophilic compounds such as hydrocarbons. Finally, differences in physiological response within the exposure to polystyrene particles, fluoranthene, or particles with adsorbed fluoranthene were assessed by the variation of heart rate patterns studied by the noninvasive laser fibre-optic method. The uniform response of individual biomarkers within the exposure groups was not recorded. There was no clear pattern in variation of acetylcholinesterase or glutathione S-transferase activity which could be attributed to the treatment. Exposure to polystyrene increased DNA damage which was detected by the comet assay but was not confirmed by micronucleus formation. Data of genotoxicity assays indicated differential responses among the groups exposed to fluoranthene alone and fluoranthene adsorbed to polystyrene. Change in the heart rate patterns within the studied groups supports the concept of the Trojan horse effect within the exposure to polystyrene particles with adsorbed fluoranthene.

Comparison of cellular mechanisms induced by pharmaceutical exposure to caffeine and its combination with salicylic acid in mussel Mytilus galloprovincialis

Urban and hospital-sourced pharmaceuticals are continuously discharged into aquatic environments, threatening biota. To date, their impact as single compounds has been widely investigated, whereas few information exists on their effects as mixtures. We assessed the time-dependent biological impact induced by environmental concentrations of caffeine alone (CAF; 5 ng/L to 10 µg/L) and its combination with salicylic acid (CAF+SA; 5 ng/L+0.05 µg/L to 10 µg/L+100 µg/L) on gills of mussel Mytilus galloprovincialis during a 12-day exposure. Although no histological alteration was observed in mussel gills, haemocyte infiltration was noticed at T12 following CAF+SA exposure, as confirmed by flow cytometry with increased hyalinocytes. Both the treatments induced lipid peroxidation and cholinergic neurotoxicity, which the antioxidant system was unable to counteract. We have highlighted the biological risks posed by pharmaceuticals on biota under environmental scenarios, contributing to the enhancement of ecopharmacovigilance programmes and amelioration of the efficacy of wastewater treatment plants.

Long-term investigation of heavy metal variations in mollusks along the Chinese Bohai Sea

Biomonitoring is an effective way to assess the effects of pollutants on marine ecosystems. As an important fishing region in China, the Chinese Bohai Sea has been contaminated with heavy metals, posing great risks to seafood safety and human health. Herein, the spatiotemporal variations in the concentrations of seven heavy metals (As, Cd, Cr, Cu, Ni, Pb, and Zn) in 11 species of mollusks (658 samples) collected from the Chinese Bohai Sea were studied during 2006-2016. The concentrations of Cr, As, Cd, and Pb in approximately 41%, 100%, 71%, and 18% of the sampled mollusks exceeded the maximum permissible levels in aquatic products set by China, indicating that the mollusks were contaminated with varied concentrations of heavy metals. Except for slight fluctuations, no significant temporal variations were observed during the sampling period, suggesting a relatively stable status of these metals. Cluster analysis showed that oyster had higher bioaccumulation potential for Zn and Cu, whereas Mactra veneriformis, Rapana venosa, Meretrix meretrix, Chlamys farreri, and Mya arenaria had higher bioaccumulation potentials for Cr, As, Ni, Cd, and Pb, respectively. These findings are useful for biomonitoring and developing guidelines for seafood consumption in coastal regions. Significant relationships were observed between heavy metal concentrations in mollusks and socioeconomic indices (gross domestic product, per capita gross domestic product, and population amount), suggesting the effects of anthropogenic activities on heavy metal contamination. Our study established a good model to evaluate the risks of heavy metals and provided a sound scientific basis for controlling seafood safety in coastal regions.

Meta-Analysis of a New Georeferenced Database on Polycyclic Aromatic Hydrocarbons in Western and Central Mediterranean Seafood

The aim of this work was to collect and harmonize the results of several studies achieved over the years, in order to obtain a database of georeferenced observations on polycyclic aromatic hydrocarbons (PAHs) in Western and Central Mediterranean seafood. For each observation, some information on the taxonomy and the ecology of the sampled species are reported, as well as details on the investigated hydrocarbon, and spatial and temporal information on sampling. Moreover, two health risk indexes were calculated for each record and included in the database. Through several statistical methods, we conducted a meta-analysis of the data on some of the species in this database, identifying trends that could be related to the biology of the investigated organisms, as well as to the physico-chemical properties of each hydrocarbon and to the oceanographic characteristic of this part of the Mediterranean. The analysis of the data showed that, at a consumption rate like the one typical of the Italian population, seafood caught from the area considered in the present work seems to pose a minimal risk to health. However, we also found evidence of an increasing trend of PAH concentrations in Mediterranean mussels, pointing to the need for constant monitoring.

Trends and potential human health risk of trace elements accumulated in transplanted blue mussels during restoration activities of Flekkefjord fjord (Southern Norway)

The monitoring of contaminants represents a priority to preserve the integrity of marine ecosystems, as well as to plan and to manage restoration activities in order to protect environmental and human health. In the present study, a 6-months active biomonitoring was performed to explore the levels of eighteen trace and toxic elements, including heavy metals (TEs; i.e. Al, As, Ca, Cd, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Sr, Ti, and Zn), accumulated in soft tissues of blue mussel (Mytilus edulis Linnaeus, 1758) individuals transplanted at different depths (5- and 15-m depth) in five locations within the Flekkefjord fjord (Southern Norway). As this area suffered a long-lasting contamination due to both organic and inorganic contaminants, a series of restoration activities were activated to tackle and to prevent potential risks for ecosystem and local population. Our results demonstrated that the levels of TEs accumulated in edible tissues of transplanted mussels in the Flekkefjord fjord were generally low before the beginning of the restoration activities. However, location- and time-specific differences in the accumulation of TEs were noted after the implementation of such activities. Interestingly, the levels of Fe and Mn significantly increased after the beginning of the restoration activities, likely because the release of these TEs from the slag used in such operations and/or resuspension of contaminated sediments. However, assuming that native mussels can accumulate the same TEs at levels measured in transplanted individuals, our results suggest a substantial safety for human consumption of native mussels from the Flekkefjord fjord, regardless of restoration activities.

Methylmercury and Polycyclic Aromatic Hydrocarbons in Mediterranean Seafood: A Molecular Anthropological Perspective

Eating seafood has numerous health benefits; however, it constitutes one of the main sources of exposure to several harmful environmental pollutants, both of anthropogenic and natural origin. Among these, methylmercury and polycyclic aromatic hydrocarbons give rise to concerns related to their possible effects on human biology. In the present review, we summarize the results of epidemiological investigations on the genetic component of individual susceptibility to methylmercury and polycyclic aromatic hydrocarbons exposure in humans, and on the effects that these two pollutants have on human epigenetic profiles (DNA methylation). Then, we provide evidence that Mediterranean coastal communities represent an informative case study to investigate the potential impact of methylmercury and polycyclic aromatic hydrocarbons on the human genome and epigenome, since they are characterized by a traditionally high local seafood consumption, and given the characteristics that render the Mediterranean Sea particularly polluted. Finally, we discuss the challenges of a molecular anthropological approach to this topic.

Variability of metabolic, protective, antioxidant, and lysosomal gene transcriptional profiles and microbiota composition of Mytilus galloprovincialis farmed in the North Adriatic Sea (Italy)

This study evaluates the transcriptional profiles of genes related to physiological responses in digestive glands (DG) of Mytilus galloprovincialis under the influence of seasonal changes of environmental variables, gender bias, and gonadal development. Composition of the DG microbiome was also explored. Mussels were collected across 7 months encompassing 3 seasons from a farm in the Northwestern Adriatic Sea. All gene products showed complex transcriptional patterns across seasons. Salinity, surface oxygen and transparency significantly correlate with transcriptional profiles of males, whereas in females temperature and gonadal maturation mostly explained the observed transcriptional changes. Seasonal variations and gender-specific differences were observed in DG microbiome composition, with variations resembling metabolic accommodations likely facing season progression and reproductive cycle. Results provide baseline information to improve actual monitoring strategies of mussel farming conditions and forecast potential detrimental impacts of climatological/environmental changes in the study area.

Monitoring of Polycyclic Aromatic Hydrocarbon Levels in Mussels (Mytilus galloprovincialis) from Aquaculture Farms in Central Macedonia Region, Greece, Using Gas Chromatography-Tandem Mass Spectrometry Method

A new sensitive and selective gas chromatography tandem mass spectrometry (GC-MS/MS) method was developed for the analysis of 26 polycyclic aromatic hydrocarbons (PAHs), including 16 Environmental Protection Agency (EPA) and 15 + 1 European Union (EU) PAHs, in mussel samples from aquaculture farms in Thermaikos and Strymonian Gulf, Central Macedonia Region, in three sampling periods. Concentrations were found at moderate to low values at all sampling sites, without exceeding maximum levels set by EU. Low molecular weight PAHs were predominant in all samples. Seasonal variation of the concentrations was observed; values were slightly higher in the winter period. Use of diagnostic ratios for potential sources of PAHs showed both petrogenic and pyrolitic origin. In comparison to other related studies of mussels from the Mediterranean Sea, Greek mussels cultivated in the studied gulfs are low in contaminants due to minimal environmental pollution effects. Low concentrations of PAHs are in compliance with the low values of other POPs which were found in the mussels.

Effect of physiological conditions and biochemical factors of mussels Mytilus galloprovincialis in radioactivity monitoring programs along the Algerian coast

A study was carried out to determine the activities of radionuclides (¹³⁷Cs, ⁴⁰K, ²²⁶Ra, ²¹⁴Bi, ²¹⁴Pb, and ²¹⁰Pb) and the levels of biochemical components (lipids, carbohydrates, and proteins) in mussels (Mytilus galloprovincialis) along the Algerian coast. The goal was to evaluate the effect of mussels' biological parameters on radionuclide concentrations, through two coastal water biomonitoring programs. The mussels were taken from three study areas on the Algerian coast: Kristel (Oran), Surcouf (Alger), and Collo (Skikda), for the passive biomonitoring program and transplanted from each study area into the control site of Surcouf. Biochemical components were determined by means of UV-visible colorimetric assays, while the activity concentrations of radionuclides were measured by gamma-ray spectrometry. The results showed that carbohydrates were the most abundant biochemical components (40-60%) compared with proteins (20-40%) and lipids (15-20%). ¹³⁷Cs activity concentrations were below the lower limit of detection (LOD) for all samples, while the high activities of ⁴⁰K are the result of its behavior as stabile potassium K which is extensively used in the metabolism of mussels reflects the conditional state of mussels. ²¹⁰Pb concentration reflects the conditional state of mussels (morphometric parameters and proteins content). The mussels' bioaccumulation capacity for radionuclides was found to be dependent on the growing site and the biomonitoring time period.

Total mercury content in the California ribbed sea mussel Mytilus californianus from the west coast of Baja California, México: Levels of contamination and human health risk

We analyzed spatial and temporal variations in total mercury concentration (THg) in Mytilus californianus from the west coast of Baja California, México, and assessed the potential risk for human health. The sites from the northern zone showed the highest levels of THg over the entire three years of study, however, no significant differences among years were found. The highest level of THg (0.110 μg/g d.w.) was recorded in 2010 at Bajamar (SS2), and the lowest (0.011 μg/g d.w.) in 2007 and 2008 at Eréndira (SS4) and Los Ojitos (SS7), respectively. The estimated daily intake (EDI) values for adults through mussel consumption were lower than the oral reference dose (RfDo) and the acceptable daily intake (ADI) values established by the USEPA and the FAO/WHO, respectively. The target hazard quotient (THQ) values were <1.0, indicating that mercury concentrations in M. californianus are not likely to pose a risk for human health.

Spatial trace element bioaccumulation along with consumer risk simulations of Mediterranean mussels in coastal waters of Turkey

Turkey borders three seas and the most populous locations are squeezed into the coastal territories. Thus, organisms living in these aquatic territories are under longstanding anthropogenic pressure. Hence, this study investigated the consumption outcomes leading to potential child and adult health risks along with the spatial distribution of As, Cd, Cr, Cu, Ni, Pb, V, and Zn in the Mediterranean mussels (Mytilus galloprovincialis) sampled at 23 different stations from the Black Sea, the Sea of Marmara, and the Aegean Sea coastal waters of Turkey. The mean concentrations of trace elements found in the Mediterranean mussels followed Zn (39.75 mg kg^-1) > Cu (1.95 mg kg^-1) > As (1.84 mg kg^-1) > Pb (0.99 mg kg^-1) > Ni (0.65 mg kg^-1) > Cr (0.62 mg kg^-1) > V (0.47 mg kg^-1) > Cd (0.08 mg kg^-1). Factor analysis revealed that trace elements were mostly derived from anthropogenic sources. Pb values were found to be above the permissible European Union limits at 10 sampling stations. While the estimated weekly intake did not exceed the Joint FAO/WHO Expert Committee on Food Additives limits, the target hazard quotient for As was found >1 for children. The lifetime cancer risk (CR) for adults and children was unacceptable (>10^-4) at high consumption rates for As according to US Environmental Protection Agency. Monte Carlo simulation confirmed a CR to adult (62.98%) and children (97.24%) mussel consumers caused by As.

Sex- and sexual maturation-related aspects of the element accumulation in soft tissues of the bivalve Mytilus galloprovincialis Lam. collected off coasts of Sevastopol (southwestern Crimea, Black Sea)

Mussels are widely used to monitor trace element pollution, but the role of their sex and sexual maturation in the element accumulation was not comprehensively studied and the number of elements under consideration never exceeded three dozen. In this work, concentrations of 67 elements in different tissues of females and males of the Mediterranean mussel are determined. Statistically significant differences are obtained in the element composition of analogous tissues of mussel males and females and in gonads of the same sex at different sexual maturation stages. The significantly higher concentrations of some elements found in gonads of females (Mn, Zn, As) and males (P) at most of the sexual maturation stages suggest essentiality of these elements in the reproduction. Elements exhibit several accumulation patterns in gonads during the ripening, with the most general one being the accumulation after spawning. Indications of a new phenomenon of circulation of most elements in gonads over the reproductive cycle are obtained, with the element concentrations decreasing at the first two stages and increasing at the posterior stages. Principal component analysis shows that the differences in the element accumulation are mainly due to the element uptake pathways and sexual differentiation. The most important identified factors determining the decrease in concentrations of tissue elements are their redistribution over mussel's body, biomass dilution, sequestration, and release with gametes. Five detected non-overlapping clusters of the non-normalized element concentrations in the pooled mussel tissues are associated with macroelements, two groups of trace elements, and two groups of ultratrace elements.

Natural Polonium-210 in Bivalve Species in Peninsular Malaysia Waters as Recent Pollution Indicator

Po-210 is an alpha rays emitter in U-238 decay series and a natural radionuclide found in the ocean, and bivalve is the best biological indicator compared to the other organisms because of their feeding methods that are filter-feeding and suspension-feeding. They are able to accumulate toxic substances from marine environment in their tissue and researches were conducted in edible tissues of Meretrix meretrix, Perna virid, Glauconome virens, Anadara granosa, Anadara ovalis, Pholas orientalis, Donax sp., Polymesoda bengalensis, Phapia undulata, and Tellina virgate. Result showed Po-210 activity distributions were ranging from 2.61 ± 1.50 to 517.46 ± 56.64 Bq/kg. The lowest value of Po-210 activity recorded in Anadara granosa and the highest value recorded in Donax sp. Small-sized of bivalve species contained higher Po-210 activity than the larger one. Higher Po-210 contents in bivalve obtained from the west coast of Peninsular Malaysia might be closely related to anthropogenic factors from the coastline. This study also found that Donax sp. is able to be a good indicator of environmental pollutants as it accumulates Po-210 in higher concentrations than other bivalve species. Donax sp. can be found in several parts of Malaysia and available in large quantities but it appears to be seasonal. While for seafood safety monitoring, Anadara granosa is capable of becoming a good benchmark for seafood security as it found in most parts of Malaysia. It is not seasonal and a kind of Malaysian favorite seafood.

Heavy metal spatial and temporal trends (2008-2018) in clams and mussel from Adriatic Sea (Italy): Possible definition of forecasting models

In 2008-2018, 1458 georeferenced samples of clams and 343 of mussels were harvested in Italy from classified areas along Marche coast and analyzed within food-safety monitoring plans. Pb, Cd, V, Ni, Cr, and As median levels (mg kg^-1) were 0.09, 0.08, 0.29, 0.77, 0.35, and 2.35 in clams and 0.16, 0.15, 0.46, 0.48, 0.25, and 3.34 in mussels. The reported levels were comparable with the published ones, and Hg always fell below LOQ (0.025 mg kg^-1). Pb and Cd datasets, based on quarterly results, show a decreasing trend in clams and constant baseline value for mussels. Time-trends and forecasting models represent an asset to predict emerging food safety/security risks. The metal levels in mussels and clams from the same area allow environmental safety assessment and thus enable the evaluation of contaminants in both water column and sediment. Monitoring of elements that are not regulated may help in preserving food and environmental safety.

Microplastics and their associated organic pollutants from the coastal waters of the central Adriatic Sea (Italy): Investigation of adipogenic effects in vitro

Even though microplastic (MP) pollution in aquatic environment is nowadays widely studied, a huge gap of knowledge exists on their actual biological effects. In this study we first reported environmental baseline data on the occurrence and characterization of floating MPs in Italian coastal waters of the Central Adriatic Sea by using a standardized monitoring protocol. Further, we analyzed the concentrations of MP-associated chemicals and evaluated their potential adipogenic effects using 3T3-L1 preadipocytes. MPs were found in each sampling stations showing the highest abundance (1.88 ± 1.78 items/m³) in the sites more distant from the coast with fragments as the most common shape category. All targeted organic pollutants (i.e. polychlorinated biphenyls - PCBs, polycyclic aromatic hydrocarbons -PAHs, organophosphorus - OP, and organochlorine - OC pesticides) have been detected on the surface of the collected MPs. The highest concentrations of PAHs were found on MPs from inshore (i.e. <1.5 NM) surface waters with low-ring PAHs as dominant components. Similarly, MPs from inshore waters had higher ΣPCB concentrations (64.72 ng/g plastic) than those found in offshore (i.e. >6 NM) waters (10.37 ng/g plastic). Among pesticides, all measured OPs were detected in each sample analyzed with pirimiphos-methyl as the most representative compound. For OCs, the sum of all concentrations of congeners was higher in coastal with respect to offshore waters. Moreover, in vitro 3T3-L1 screening of MP extracts indicated potential metabolic effects resulting in both adipogenesis and lipid uptake/storage.

Source Apportionment Assessment of Marine Sediment Contamination in a Post-Industrial Area (Bagnoli, Naples)

The area of Bagnoli (Gulf of Naples, central Tyrrhenian Sea) has been heavily exposed to pollution for over a century due to the presence of industrial sites along its coastline. The aim of this study is to analyze contaminant concentrations (i.e., heavy metals and hydrocarbons) in seabed sediments through a statistical multivariate approach. Multivariate methods permit us to describe the pollution dynamics affecting the area and distinguish between anthropogenic and natural pollution sources. Additionally, the association between contamination patterns and the wave climate characteristics of the gulf (i.e., wave period, direction, height, power, and energy) is investigated. The study confirms that the main contamination source in the Bagnoli bay is anthropogenic activities (i.e., former steel plant and sewage discharges) for the majority of investigated pollutants. It also provides evidence, however, for the potential co-existence of multiple anthropogenic and geogenic sources of arsenic and other metals that may be originating also from the water-rock interaction and submarine volcanic emissions in the Phlegraean area.

Seasonal distribution of cadmium, lead, nickel, and magnesium in several tissues of mussels from the Algerian coasts

This study aims to investigate the distribution of heavy metals (Cd, Pb, Ni, and Mn) in different organs of two marine mussel species, Perna perna collected from Figuier site and Mytilus galloprovincialis sampled from Sercouf and Algiers port sites of the Algerian coast. Thirty individuals (>5 cm length) were seasonally sampled over a 1-year period from each site, and condition index (CI) and gonado somatic index (GSI) of mussels were calculated. The gill, digestive gland, rest of soft tissues, and gonad were accurately isolated and heavy metal contents were analyzed by ICP-MS. Heavy metal results, expressed on μg/g dry weight, ranged from 0.1 to 2.6 Cd, 0.1 to 17.15 Pb, 0.36 to 25.7 Ni, and 3.68 to 74.76 Mn. Thus, typical distribution of studied metals in various organs of mussels was found. In fact, the digestive gland followed by gill revealed significantly high metal concentrations. However, gonad showed low heavy metal contents. Different patterns of heavy metal distribution in various organs of mussels were found at the three sampling sites. High levels of Cd, Pb, Ni, and Mn were detected in mussels of Sercouf, Algiers port, and Figuier sites, respectively. According to the Algerian and European norms, mussels collected from all sites were healthy except those of Algiers port sampled in autumn and winter seasons where lead contamination was found.

Organochlorines Accumulation in Caged Mussels Mytilus galloprovincialis—Possible Influence of Biological Parameters

The accumulation of organochlorines (OCs) in mussel tissue depends on the physiological and biochemical status of the organism and its interaction with the environment. Mytilus galloprovincialis, 2- and 1-year-old mussels, sampled from Mali Ston Bay, a reference area, and transplanted to Kaštela Bay in cages, were used for the assessment of OC levels and influence of biological parameters on accumulation. Results of bimonthly exposures during one year highlighted that OC accumulation decreases with increasing mussel age. Polychlorinated biphenyls (PCBs) and p,p′-dichlorodiphenyltrichloroethane (p,p′-DDTs) increased, while organochlorine pesticide (OCP; i.e., HCB, lindane, heptachlor, and aldrin) variations were very low. Statistical analysis generally did not confirm the significant effect of lipid content on the accumulation of OCs in mussel tissue. OC levels in mussels were below the maximum permitted levels for human consumption (European Commission).

Mytilidae as model organisms in the marine ecotoxicology of pharmaceuticals - A review

Growing production and consumption of pharmaceuticals is a global problem. Due to insufficient data on the concentration and distribution of pharmaceuticals in the marine environment, there are no appropriate legal regulations concerning their emission. In order to understand all aspects of the fate of pharmaceuticals in the marine environment and their effect on marine biota, it is necessary to find the most appropriate model organism for this purpose. This paper presents an overview of the ecotoxicological studies of pharmaceuticals, regarding the assessment of Mytilidae as suitable organisms for biomonitoring programs and toxicity tests. The use of mussels in the monitoring of pharmaceuticals allows the observation of changes in the concentration and distribution of these compounds. This in turn gives valuable information on the amount of pharmaceutical pollutants released into the environment in different areas. In this context, information necessary for the assessment of risks related to pharmaceuticals in the marine environment are provided based on what effective management procedures can be developed. However, the accumulation capacity of individual Mytilidae species, the bioavailability of pharmaceuticals and their biological effects should be further scrutinized.