Mussel Tissue Research Articles

Combining microcavity size selection with Raman microscopy for the characterization of Nanoplastics in complex matrices

Nanoplastic particulates (pNP) are widely considered as being potentially harmful to the environment and living organisms while also being technically difficult to detect and identify in the presence of biological matrices. In this study, we describe a method for the extraction and subsequent Raman analysis of pNP present in the tissues of salt-water mussels. The process combines a step of enzymatic digestion/filtering to eliminate the biological matrix with a detection/identification procedure, which uses a micro-machined surface, composed of arrays of cavities with well-defined sub-micron depths and diameters. This sensor surface, exploits capillary forces in a drying droplet of analyte solution to drive the self-assembly of suspended nanoparticles into the cavities leaving the individual particles isolated from each other over the surface. The resulting array, when analysed using confocal Raman microscopy, permits the size selective analysis of the individual sub-micron pNP trapped in the cavities structure.

ANTIBACTERIAL ACTIVITY OF DIFFERENT EXTRACTS OF BLACK MUSSEL (MYTILUS GALLOPROVINCIALIS) FROM THE BLACK SEA, BULGARIA

Background: Over the past decade, there has been a growing interest in sea bivalves, which are an inexpensive and easily accessible source of high-quality proteins, lipids and secondary metabolites with antimicrobial and anti-fungal potential. Farmed Black Sea mussel (M. galloprovincialis) are promising objects for the study of their antimicrobial potential. Purpose: The aim of this work is to determine the antibacterial activity of different extracts from the Black Sea mussel Mytilus galloprovincialis tissues by using the disc diffusion method with cultures of Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. Material/Methods: Extraction of mussel tissues was done with different solvents: ethyl acetate (100%), methanol (100%), glycerol:water (50%, 1:1 v/v), ethanol (50%), acetone (70%), hot water. Antimicrobial activities of these extracts from Mytilus galloprovincialis was assessed by the disc-diffusion method. Results: Testing antibacterial activity of black mussels revealed that ethyl acetate extract showed the highest activity against Еscherichia coli (13 mm) and Klebsiella pneumoniae (11 mm) and no activity against Staphilococcus aureus. The glycerol: water extract showed growth inhibition effect against Staphylococcus aureus (11 mm) and Escherichia coli (10 mm), but no effect against Klebsiella pneumoniae. Conclusions: The preliminary information presented in this study showed that the Black Sea farmed mussel could be an interesting source of antibacterial compounds. The glycerol-water extracts of Mytilus galloprovincialis had low antimicrobial activities against Staphylococcus aureus and more important against Escherichia coli.

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.

Histopathology of the Foot, Gill and Digestive Gland Tissues of Freshwater Mussel, Lamellidens marginalis Exposed to Oil Effluent

We investigated the histopathological alterations in the tissues of freshwater mussel, Lamellidens marginalis in response to oil effluent. Based on the previous acute toxicity, two sub lethal [1/4th (11.88ppt) and 1/10th (8.55ppt)] concentrations of oil effluent (hydrocarbon) were prepared and exposed to mussels. In a first series of experiment, animals were exposed/accumulated for 30 days [Ist, 8th, 15th, 22nd and 30th days] by two sub lethal concentrations of oil. In a second series of experiment, oil exposed animals were thereafter transferred to clean water and kept in it up to 30 days [Ist, 8th, 15th, 22nd and 30th days] to assess the recovery pattern (depuration). At seven-day intervals, histopathological alterations were analyzed in foot, gill and digestive gland tissues of mussel. First series of experimental observation showed remarkable damages in foot (disorganized outer epithelium, necrosis of the cell, the formation of lumina, disorganized muscle bundle); in gill (disruption of gill filaments, odema formation, necrosis, dis-aggregated cilia) and in digestive gland (stoma, detached glandular epithelium, vertical clefts, presence of leucocytes, dense accumulation of luminal material) and also oil effluent inducement are confirmed with the aforementioned results. At second series of experiment, it was found that oil effluent tended to accumulate in tissues in a duration-dose-dependent manner. Tissue burden by oil effluent of mussels completely were restored at 30th day. The present experimental findings may be of early warning signals of oil effluent pollution. In conclusion oil effluent are highly toxic to the Lamellidens marginalis.

Biomonitoring study of trace metals (Al, As, Li) in mussels from Al Hoceima coastline of Moroccan Mediterranean Sea

Mytilus galloprovincialis are commonly used as heavy metal biomonitors across the world. In the present work, the contents of three elements (Al, As, Li) were analyzed in Mytilus galloprovincialis using Inductively Coupled Plasma – Optical Emission Spectrometry (ICP-OES 720-ES). Samples of soft tissues are collected monthly in 2020, from three sites of the mussel farming facilities installed in the Al Hoceima Sea. The decreasing order of the mean element contents in mussel tissues was Al > As > Li. The lowest values of metallic elements were found in summer and the highest contents were indicated in winter. Positive correlations were indicated between these elements and chlorophyll a indicating the importance of diet for the bioaccumulation of metals in mussels. In addition, our results show that the temperature and the salinity increase with the decreasing of metals bioavailability suggesting the influence of chemical properties and physical kinetics changes in the solution. On the other hand, the strong correlations observed for metal contents in mussel tissues can be elucidated by their common sources. The results of this study may be useful in the use of M. galloprovincialis, in the environmental biomonitoring studies.

Bioaccumulation and health risk assessment of trace elements inMytilus galloprovincialisas sea food in the Al Hoceima coasts (Morocco)

The monthly variations in metal concentration of Cadmium (Cd), Zinc (Zn) and Chromium (Cr) were determined in tissues ofMytilus galloprovincialisand seawater obtained from the mussel farm installed along the Al Hoceima coasts, during the sampling period of 2018. The heavy metals encountered in the bivalves were higher than those observed in their environment with a decreasing order of Zn > Cr > Cd. The results also showed a decreasing trend for the metals studied during the summer sampling campaign. The maximum values were obtained during the wet periods. The monthly variations in trace metals observed in the mussel tissues were due to environmental parameters and the physiological state of the bivalves. Our results revealed that the average concentrations of pollutants found inM. galloprovincialiswere below the limits allowed by the Food and Agriculture Organization of the United Nations (FAO) which are 2.0, 1000 and 1.0 mg/kg, for Cd, Zn and Cr, respectively in molluscan shellfish for human consumption. Therefore, the trace elements present in the tissues of Al Hoceima shore mussels do not represent a risk to human health associated with their consumption, even during the period of their maximum bioaccumulation. Our work highlights the potential use ofMytilus galloprovincialisin the Biomonitoring of metallic pollutants in this region of the northern Moroccan coasts.

Higher bioavailability of Cu and Zn in the eastern part of Johore Causeway: Will the pattern remain the same beyond 2030?

The purpose of this paper is to discuss Cu and Zn concentrations in Perna viridis soft tissues from the western and eastern parts of Johore Singapore Causeway. The polluted eastern portion of the Causeway had greater levels of Cu and Zn in different areas of the soft tissues of mussels than the western part. This indicated the eastern section of the semi-enclosed Causeway had higher Cu and Zn bioavailability than the western part. With some reports of high metal levels in the eastern part of the Causeway from 2015 to 2018, it is predicted that there will be a plausible constant source of anthropogenic metal contamination in the eastern part of the Causeway beyond 2030 if anthropogenic activities are not effectively controlled.

Effects of ultrasound on invasive golden mussel Limnoperna fortunei mortality and tissue lesions

Biofouling by the invasive golden mussel Limnoperna fortunei deleteriously affects artificial water systems, but few effective, environmentally friendly antifouling strategies exist. We propose ultrasound for control of this invasive mussel and report minimum exposure times to kill juveniles and adults at ultrasonic powers ranging 300–600 W from a fixed distance of 8.5 cm. Analysis using a PMA + RT-qPCR assay revealed the formation of tissue lesions in response to ultrasound, with gill tissue more prone to injury than adductor muscle tissue. Shell microstructure determined using scanning electron microscopy (SEM) + energy dispersive X-ray spectroscopy (EDS) is plywood-like, with a thicker shell and increased numbers of prism and nacre layers in adult mussels that provide greater resistance to ultrasound, reducing mortality and tissue lesions. Our results suggest L. fortunei biomass could be effectively reduced by ultrasound, especially for early life-history stages without, or with only immature shells.

Direct Determination of Cadmium, Lead, and Zinc in Mussels by Two-Stage Probe Atomization (TPA) Graphite Furnace Atomic Absorption Spectrometry (GFAAS)

Seafood consumption may induce health risks due to its contamination by pollutants. In this study, the two-stage probe atomization technique (TPA) was combined with graphite furnace atomic absorption spectrometry (GFAAS) to develop a novel procedure for determining Cd, Pb and Zn in mussels collected in the Sea of Japan (Russia). The application of TPA eliminated organic matrix interferences during GFAAS determination of heavy metals and allowed significant reduction of the sample pretreatment processes. The procedure involved the formation of a suspension of treated lyophilized mussels that were inserted into graphite furnace. The limits of detection using the optimized conditions were 0.8, 10, and 0.4 ng/g for Cd, Pb, and Zn, respectively. Inductively coupled plasma – optical emission spectrometry (ICP-OES) was employed to characterize the accuracy of the developed technique. The concentrations of heavy metals in Crenomytilus Grayanus mussel tissues from Peter the Great bay did not exceed 8.2, 31 and 475 μg/g for Cd, Pb, and Zn and are considered to have no negative effects upon human health.

Mussel: a potential pollution indicator in the aquatic ecosystem and effect of climate change

The study of ecological indicators, defining and establishing the means of measuring the health of the environment, is of great importance. The most important elements of ecosystems are the biological components, and environmental impact assessment of ecosystems will therefore require that these components are seriously laid out. It is, for example, not sufficient to assess the water quality by the use of physicochemical parameters, although their determination can be carried out much more rapidly. There exists, in general, a relation between species composition and water quality. It is well known that mussels are extensively utilized as a biological indicator of pollution of both marine and freshwater ecosystems. The reason is that the mussel is a sessile, filter-feeding, and able to accumulate within its tissues many of the contaminants. In addition, mussels show a wide geographical distribution as they permit the survey of extensive coastal and inland areas. The contaminants accumulated in the tissues of mussels may cause a “stress syndrome” with alteration to their physiology. On the other hand, global warming does affect the pH level, especially the marine water resulting increase in acidity. This can be the outcome of the existing genetic variation in natural populations of mussels. They because allow themselves to adapt to declining pH levels in the aquatic ecosystem caused by carbon emissions. We, therefore, focus on the factors that possibly effect the mussel biodiversity in aquatic ecosystems in relation to climate change as well as pollution concerned.

Mussels get higher: A study on the occurrence of cocaine and benzoylecgonine in seawater, sediment and mussels from a subtropical ecosystem (Santos Bay, Brazil)

Data on the occurrence of cocaine (COC) and benzoylecgonine (BE) in marine environmental compartments are still limited, with few studies reporting superficial water contamination, mainly in tropical zones. In this sense, environmental data of these substances are essential to identify potential polluting sources, as well as their impact in costal ecosystems. The aim of this study was to evaluate the occurrence of COC and BE in seawater, sediment and mussels from a subtropical coastal zone (Santos Bay, São Paulo, Brazil), as well as to determine a field measured Bioaccumulation Factor (BAF). COC and BE were detected in all water samples in concentrations ranging from 1.91 ng·L−1 to 12.52 ng·L−1 and 9.88 ng·L−1 to 28.53 ng·L−1, respectively. In sediments, only COC was quantified in concentrations ranging from 0.94 ng·g−1 to 46.85 ng·g−1. Similarly, only COC was detected in tissues of mussels 0.914 μg·kg−1 to 4.58 μg·kg−1 (ww). The field-measured BAF ranged from 163 to 1454 (L·kg−1). Our results pointed out a widespread contamination by cocaine and its main human metabolite benzoylecgonine in Santos Bay. Mussels were able to accumulate COC in areas used by residents and tourists for bathing, fishing, and harvest, denoting concern to human health. Therefore, our data can be considered a preliminary assessment, which indicates the need to evaluate drugs (including illicit as COC) in environmental and seafood monitoring programs, in order to understand their risks on the ecosystem and human health.

Fatty Acids Distribution in Seston, Tissues, and Faecal Pellets of Blue Mussels Mytilus edulis L.

The n-3 polyenoic fatty acids (phytoplankton origin) dominate in the fatty acid composition of seston, which is a food source for bivalves; this indicates the predominance of diatoms in the seston composition. The distribution of the main classes of lipids and their fatty acids in the tissues of blue mussels depends on the mollusk body size. As the body size of the mollusk increases, the ratio of membrane lipids decreases, and high-energy saturated and monounsaturated fatty acids accumulate in storage lipids. The bulk of the n-3 polyenoic acids consumed by mollusks in seston (i.e., their food) accumulates in the tissues of mollusks and is used for their metabolism, whereas the long-chain saturated fatty acids, oleic acid and the n-6 polyenoic acids, are excreted with faecal pellets.

First Report of Zoonotic Genotype of Giardia duodenalis in Mussels (Mytilus edulis) from Patagonia Argentina.

Blue mussels (Mytilus edulis) are among the most consumed fishery products globally. Foodborne outbreaks of mussel-associated infections by viral, bacterial, and parasitic pathogens have been reported in the last years. In this study, we investigated the occurrence, genetic diversity, and zoonotic potential of the diarrhea-causing enteric protozoan Giardia duodenalis in blue mussels from Caleta Córdova in Chubut Province, southeast Patagonia, Argentina. A total of 344 free-living blue mussels were collected and distributed in 53 aliquots of pooled mussel tissue (each containing 5‒7 specimens) during the period 2015‒2018. Conventional optical microscopy was used as screening method for the detection of G. duodenalis cysts in pooled, homogenized tissues. Samples with a positive result were assessed by a multilocus sequence genotyping scheme based on the amplification of partial fragments of the glutamate dehydrogenase and β-giardin genes of the parasite. G. duodenalis cysts were found in 30.2% (16/53) of the aliquots of pooled mussel tissue tested. PCR and sequencing analyses revealed the presence of G. duodenalis subassemblage BIV in selected aliquots. To the best of our knowledge, this is the first description of zoonotic subassemblage BIV from blue mussels in Argentina.

Environmental exposure of freshwater mussels to contaminants of emerging concern: Implications for species conservation

Contaminants of emerging concern (CECs) are prevalent in aquatic landscapes and may be a factor in population declines of aquatic and terrestrial fauna. Yet, there are limited data to assess the impacts of CECs to species. Understanding CEC impacts is particularly important for imperiled freshwater mussels which provide valuable ecosystem services. CEC exposure of freshwater mussels was characterized by evaluating sites with and without the federally endangered mussel (Villosa fabalis) in three subwatersheds of the Maumee River, Ohio, USA, a tributary of the Great Lakes Basin. Analyses of water, sediment, and tissue concentrations of two common mussels (Eurynia dilatata and Lampsilis cardium) indicated different CEC exposures across all 6 sites. Distinct CEC signatures were found across the three media types suggesting as mussels interact with water and sediment they may be experiencing different exposure concentrations and mixtures of CECs at different life stages. Of the 83 CECs which were detected, agricultural CECs dominated sediments, pharmaceuticals were common in tissues and water, and 16 of the 83 CECs were found co-occurring in mussel tissue, water, and sediment. There were no species differences in the CEC signatures indicating all mussels, including species of concern, may be experiencing similar exposure. Comparisons to known CEC standards indicate some exceedances in the Maumee watershed including locations of federally listed mussel species. This study provides evidence of the complexity of CEC mixes in a Great Lakes watershed and the need to understand how CECs impact declining aquatic fauna.

Fatty acid esters of azaspiracids identified in mussels (Mytilus edulis) using liquid chromatography-high resolution mass spectrometry.

Azaspiracids (AZAs) are lipophilic polyether toxins produced by Azadinium and Amphidoma species of marine microalgae. The main dinoflagellate precursors AZA1 and AZA2 are metabolized by shellfish to produce an array of AZA analogues. Many marine toxins undergo fatty acid esterification in shellfish, therefore mussel tissues contaminated with AZAs were screened for intact fatty acid esters of AZAs using liquid chromatography-high resolution mass spectrometry. Acyl esters were primarily observed for AZAs containing hydroxy groups at C-3 with 3-O-palmitoylAZA4 identified as the most abundant acyl ester, while other fatty acid esters including 18:1, 16:1, 17:0, 20:2 and 18:0 acyl esters were detected. The structures of these acyl derivatives were determined through LC-MS/MS experiments, and supported by periodate cleavage reactions and semi-synthesis of palmitate esters of the AZAs. Esters of the hydroxy groups at C-20 or C-21 were not observed in mussel tissue. The relative proportion of the most abundant AZA ester was less than 3% of the sum of the major free AZA analogues. These findings reveal an additional metabolic pathway for AZAs in shellfish.

Forensic tracers of exposure to produced water in freshwater mussels: a preliminary assessment of Ba, Sr, and cyclic hydrocarbons

Hydraulic fracturing is often criticized due in part to the potential degradation of ground and surface water quality by high-salinity produced water generated during well stimulation and production. This preliminary study evaluated the response of the freshwater mussel, Elliptio complanata, after exposure to produced water. A limited number of adult mussels were grown over an 8-week period in tanks dosed with produced water collected from a hydraulically fractured well. The fatty tissue and carbonate shells were assessed for accumulation of both inorganic and organic pollutants. Ba, Sr, and cyclic hydrocarbons indicated the potential to accumulate in the soft tissue of freshwater mussels following exposure to diluted oil and gas produced water. Exposed mussels showed accumulation of Ba in the soft tissue several hundred times above background water concentrations and increased concentrations of Sr. Cyclic hydrocarbons were detected in dosed mussels and principle component analysis of gas chromatograph time-of-flight mass spectrometer results could be a novel tool to help identify areas where aquatic organisms are impacted by oil and gas produced water, but larger studies with greater replication are necessary to confirm these results.

Human pharmaceuticals in marine mussels: Evidence of sneaky environmental hazard along Italian coasts

Despite the increasing interest for pharmaceuticals in the marine environment, their accumulation in wild organisms and consequent environmental hazards are still poorly known. The Mediterranean Sea is highly challenged by the density of coastal populations, large consumption of pharmaceuticals and their often limited removal by Wastewater Treatment Plants (WWTPs). In this respect, the present study aims to provide the first large-scale survey on the distribution of such contaminants of emerging concern in native mussels, Mytilus galloprovincialis from Italian coasts. Organisms were collected from 14 sites representative of relatively unpolluted marine waters along the Adriatic and Tyrrhenian Sea and analysed for 9 common pharmaceuticals including Non-Steroidal Anti-Inflammatory Drugs (NSAIDs: Diclofenac DIC, Ibuprofen IBU, Ketoprofen KET and Nimesulide NIM), the analgesic Acetaminophen AMP, the antiepileptic Carbamazepine CBZ, the antihypertensive Valsartan VAL, the anxiolytic Lormetazepam LOR and the antidepressant Paroxetine PAR. Results indicated the widespread occurrence of the majority of pharmaceuticals in mussel tissues: CBZ was measured in >90% of analysed samples, followed by VAL (>50%), PAR (>40%), and DIC (>30%), while only AMP and KET were never detected. Heterogeneous tissue concentrations ranged from a few units up to hundreds of ng/g (d.w.), while seasonal and interannual variability, investigated over 4 years, did not highlight any clear temporal trend. Limited differences obtained between the Adriatic and Tyrrhenian Sea, as well as coastal versus off-shore sampling sites, suggest that analysed levels of pharmaceuticals in mussels tissues should be considered as baseline concentrations for organisms collected in unpolluted areas of the Mediterranean. This study provided the first unambiguous evidence of the widespread occurrence of pharmaceuticals in marine mussels from Italian coasts, giving novel insights on the potential ecotoxicological hazard from such compounds in marine species.

Bioaccumulation of sediment-associated dinonylnaphthalene sulfonates in the freshwater mussel Lampsilis siliquoidea and oligochaete Tubifex tubifex

Naphthalene sulfonic acids (NSAs) are used primarily as additives in a wide range of industrial products (e.g., rubber materials, coatings, sealants, fuels, paints). Based on modeled physicochemical properties, NSAs would likely partition into sediments or the tissues of biota in an aquatic system. This study examined the potential for three NSAs, dinonylnaphthalene disulfonic acid (DNDS), barium dinonylnaphthalene sulfonate (BaDNS), and calcium dinonylnaphthalene sulfonate (CaDNS), to accumulate in the tissue of a freshwater mussel (Lampsilis siliquoidea) and oligochaete worm (Tubifex tubifex). The ability of L. siliquoidea to depurate accumulated chemical was also assessed. Mussels were exposed via sand spiked with CaDNS for 25 d, and then transferred to clean water where their ability to depurate the chemical over an additional 28 d was monitored. Worms were exposed to each of the three NSAs via spiked sediment for 28 d. NSA concentrations were measured separately in gill, foot, and remaining soft tissues (viscera) for mussels and in whole body tissue samples of worms. For L. siliquoidea, the largest concentration of CaDNS was measured in the gill tissue; once removed from CaDNS exposure, mussels were able to depurate up to 87% of the CaDNS from their tissues in 28 days. The biota-sediment accumulation factors (28-d BSAFs) for T. tubifex were 2.8–5.2, 0.53–0.76, and 0.83–1.11 for DNDS, BaDNS, and CaDNS, respectively. For mussel gill and viscera, BCFK values were 14.07 and 16.39, respectively. When BAFKs were calculated using the concentration of CaDNS in sand, they were 1.11 and 1.29 for mussel gill and viscera, respectively. These values are much lower than what would be necessary to classify this chemical as bioaccumulative; however, the BSAFs for DNDS in T. tubifex indicated a potential biomagnification concern if this compound were to occur in the aquatic environment.

Association of aerobic anoxygenic phototrophs and zebra mussels, Dreissena polymorpha, within the littoral zone of Lake Winnipeg

While nutrient loading has affected all levels of Lake Winnipeg’s ecology, its greatest influence has likely been on the microbial community. In addition to eutrophication, zebra mussels (Dreissena polymorpha) have recently invaded the ecosystem and threaten food web dynamics. Their filter-feeding predation and association with bacteria, specifically phototrophs, was investigated. A sampling trip to Lake Winnipeg in October 2017, focused on the isolation, enumeration, and identification of aerobic anoxygenic phototrophs in littoral water, sediment, and tissues of mussels. Gimli, Patricia, and Grand beaches, separated by >15 km across the South Basin, had similar bacterial counts when cultivated on rich organic, BG-11, purple non-sulphur, and K2TeO3-supplemented media. Culture-based enumeration on rich organic medium revealed 1.74% of heterotrophs from littoral waters were aerobic anoxygenic phototrophs, and represented 13.98% within sediments. In contrast, 0.48, 1.15, and 0.16% of cultured heterotrophs were aerobic anoxygenic phototrophs within zebra mussel gill, gut, and gonadal tissues, respectively. High-throughput sequencing of bacterial 16S V4 rDNA maintained similar trends in respective bivalve organs, where 0.22, 1.13, and 0.20% of total 16S genes belonged to these phototrophs. Several Sphingomonadaceae isolates were recovered from gut tissues, all with filamentous morphology large enough for predation. Bioaccumulation of metals was also studied in D. polymorpha. All tested associated aerobic anoxygenic phototrophs were capable of resisting the metalloid oxide tellurite. The consistent distribution of aerobic anoxygenic phototrophs within microbial communities across Lake Winnipeg, and their predominance in the gut tissues of zebra mussels suggested bacterial consumption by this invasive species.

Karbonoan oinarritutako nanomaterialen eta mikro eta nanoplastikoen eragina kutsatzaile organiko iraunkorren garraiatzaile gisa organismo itsastarretan

Industriaren eta teknologiaren garapenak ezaugarri fisiko-kimiko bereziak dituzten material berriak sortzea eragin du, eta, horien artean, nanomaterialak gero eta ugariagoak dira. Nanomaterialak gutxienez nanoeskaladun (<100 nm) dimentsio bat duten materialak dira. Gaur egun, Europako legedian ez dago nanomaterialentzako araudi berezirik, nahiz eta, haien homologo makroskopikoekin alderatuta, ezaugarri fisiko-kimiko ezberdinak agertu. Mikroplastikoak 5 mm baino txikiagoak diren plastikozko materialak dira eta nanoplastikoak, 100 nm baino txikiagoak direnak. Plastiko makroskopikoen eraginak zabal ikertu diren arren, mikroplastiko eta nanoplastikoen inguruko hausnarketa duela gutxi hasi da egiten. Nanomaterialak, mikro eta nanoplastikoak, iturri desberdinetatik iristen dira itsasora eta, beraz, itsas organismoetan eragin ditzaketen kalteen inguruko kezka zabaldu da. Gainera, nanomaterialek, mikroplastikoek eta nanoplastikoek duten azalera/bolumen erlazio handia eta hidrofobizitatea dela eta, arrisku gehigarri bat dute: kutsatzaile organiko iraunkorren garraiatzaile gisa joka dezakete itsasoan. Hau da, nanomaterialek, mikroplastikoek eta nanoplastikoek, itsasoan dauden kutsatzaile organiko iraunkorrak adsorbatu ditzakete eta haien eskuragarritasuna emendatu organismo itsastarrentzat. Lan honen xedea da karbonoan oinarritutako nanomaterialek eta mikro eta nanoplastikoek hainbat espezie itsastarretan eragindako kalte fisiologikoak zein zelula eta molekula mailako kalteak berrikustea. kalte horiek, kutsatzaile organiko iraunkordun karbonoan oinarritutako nanomaterialek, mikro eta nanoplastikoek, eragindako kalteekin alderatu ere egin nahi dira. Adibidez, mikroplastikodun mikroalgekin elikatutako muskuiluek mikroplastikoak agertu dituzte urdailaren argian, digestio epitelioan eta ehun konektiboan, eta bentzo(a)pirenoa moduko kutsatzaile organiko iraunkorra adsorbatuta duten mikroplastikodun mikroalgekin elikatutako muskuiluek bentzo(a)pirenoa metatzen dute ehunetan. Mikroplastikoek bakarrik zein kutsatzaile organikodun mikroplastikoek immunotoxizitatea, kalte fisiologikoak eta DNA mailako kalteak eragiten dizkiete muskuiluei. Hortaz, ingurune konplexu batean, hala nola itsasoan, kutsatzaileak ez direnez modu isolatuan agertzen, ezagutza hori kontuan hartu beharko litzateke, itsas ekosistemen osasuna eta segurtasuna bermatzeko.