Contribution of invasive bivalves (Dreissena spp.) to element distribution: phase interaction, regional and seasonal comparison in a large shallow lake

After introduction, the invasive bivalve dreissenids became key species in the biota of Lake Balaton, the largest shallow lake in Central Europe. The contribution of dreissenid soft tissue and shell, as biotic phases, in element distribution and its interaction with the water and upper sediment phases were examined in two basins with different trophic conditions in spring and autumn. Six metals (Ba, Cu, Fe, Mn, Pb, Zn) were detected in all investigated phases. In general, metals were abundant in the water and soft tissue in the eastern basin in spring, and in the sediment and shells in the western basin in autumn. This might be associated with the more urbanized surroundings in the eastern, and the enhanced organic matter production in the western basin. High relative shares of Ba, Cu, Mn, and Pb were associated with the water and shell samples, whereas high shares of Fe and Zn were noted in the soft mussel tissue and sediments. Results suggest that dynamics of metal uptake by dreissenids depend on the seasonal change in metabolic activity. Shell metal content is less changeable; shells might absorb metals from both the soft tissue and water phases. Metallothionein peptides, the scavengers of intracellular metals, were determined to be biomarkers of the bulk contaminants rather than only metals. The present study shows that invasive bivalves, with high abundance, filtering activity, and storing capacity can significantly contribute to element distribution in the shoreline of a shallow lake ecosystem.

The use of green mussel as bioindicator of heavy metal pollution in Indonesia: a review

Asian green mussel is a marine animal that is used as food by most Indonesians. The mussels are widely cultivated in tropical countries such as Indonesia, Malaysia, Thailand, and other Asian countries. The mussel, known as perna viridis, is marine biota that is a filter feeder in the waters. Therefore, the quality of its meat is greatly influenced by the quality of the sea in its habitat. It is a food that is quite popular with the community but can endanger public health due to the accumulation of heavy metals. This study used a literature review by collecting data related to heavy metal concentrations in green mussel tissue in Indonesia. The results showed that the mussels from several sampling locations still exceeded the maximum acceptable limits of lead (Pb), mercury (Hg), and cadmium (Cd) concentration according to the standards of the food and drug administration of the Republic of Indonesia. Consumption of green mussels can increase health risks if you frequently consume them from cultivating or catching locations that have been contaminated with heavy metals.

Microbiological Quality of Seawater and Mussels (Mytilus galloprovincialis, Lamarck 1819) in the Dubrovnik Coastal Area (Southeastern Adriatic)

This research was conducted between March 2016 and March 2017 as the first study on the water and mussel quality in the coastal area of Dubrovnik (Croatia). Bacteriological analyses were conducted simultaneously on wild mussels (Mytilus galloprovincialis) tissue and their ambient water. The total numbers of heterotrophic bacteria, total coliforms, faecal coliforms and faecal streptococci in the water were determined. Concentrations of Escherichia coli were measured in mussel. The investigated stations are located in coastal water, which is particularly influenced by climatic and anthropogenic factors interacting at the boundaries between the land and freshwater and seawater environments. Seasonal variables, such as rainfall and riverine network characteristics, determine the delivery of bacteria (including E.coli) to coastal water. Direct methods of assessing the density of heterotrophic bacteria at all sampling stations showed the characteristics of an oligotrophic area. The abundance of faecal coliform bacteria was in all cases higher within mussel tissue than in the surrounding water where levels were sometimes undetectable. Maximum E. coli concentrations in mussels and seawater were regularly recorded through the summer, with the exceptions of April 2016 and January 2017 at two stations following precipitation. Minimum faecal coliform concentrations were recorded in the winter.

Microplastics in Invasive Freshwater Mussels (Dreissena sp.): Spatiotemporal Variation and Occurrence With Chemical Contaminants

Invasive zebra and quagga mussels (Dreissena spp.) in the Great Lakes of North America are biomonitors for chemical contaminants, but are also exposed to microplastics (<5 mm). Little research has examined in situ microplastic ingestion by dreissenid mussels, or the relationship between microplastics and chemical contaminants. We measured microplastics and chemical contaminants in mussel tissue from Milwaukee Harbor (Lake Michigan, United States) harvested from reference locations and sites influenced by wastewater effluent and urban river discharge. Mussels were deployed in cages in the summer of 2018, retrieved after 30 and 60 days, sorted by size class, and analyzed for microplastics and body burdens of three classes of contaminants: alkylphenols, polyaromatic hydrocarbons, and petroleum biomarkers. Microplastics in mussels were higher in the largest mussels at the wastewater-adjacent site after 30 days deployment. However, there was no distinction among sites for microplastics in smaller mussels, and no differences among sites after 60 days of deployment. Microplastics and chemical contaminants in mussels were not correlated. Microplastics have a diversity of intrinsic and extrinsic factors which influence their ingestion, retention, and egestion by mussels, and which vary relative to chemicals. While dreissenid mussels may not serve as plastic pollution biomonitors like they can for chemical contaminants, microplastics in dreissenid mussels are widespread, variable, and have unknown effects on physiology, mussel-mediated ecosystem processes, and lake food webs. These data will inform our understanding of the spatial distribution of microplastics in urban freshwaters, the role of dreissenid mussels in plastic budgets, and models for the fate of plastic pollution.

EVOS and the Prince William Sound Long Term Environmental Monitoring Program

ABSTRACT Following the 1989 Exxon Valdez oil spill (EVOS), the Prince William Sound Regional Citizens' Advisory Council began the Long-Term Environmental Monitoring Program (LTEMP) in 1993 to track oil hydrocarbon chemistry of recovering sediments and mussel tissues along the path of the spill in Prince William Sound (PWS) and across the Northern Gulf of Alaska (NGOA) region. The program also samples sites near the Alyeska Marine Terminal (AMT) within Port Valdez, primarily to monitor tanker operations and the resulting treatment and discharge of oil-contaminated tanker ballast water. Over the last 28 years, the program has documented EVOS oil's disappearance at the spill-impacted sites (albeit buried oil still exists at a few unique sheltered locations in PWS). Within the Port, a few tanker- and diesel-spill incidents have been documented over the years, but all were minor and with recovery times of < 1 yr. Of highest concern has been the permitted chronic release of weathered oil from tankers' ballast-water that is treated and discharged at the Alyeska Marine Terminal (AMT). In earlier years (1980s–90s), with discharge volumes reaching 17–18 MGD, up to a barrel of finely dispersed weathered oil would be released into the fjord daily. Over the last two decades, total petrogenic inputs (TPAH43) into the Port have declined as measured in the monitored mussels and sediments. This trend reflects a combination of decreased Alaska North Slope (ANS) oil production and thus, less tanker traffic, plus less ballast from the transition to double-hulled tankers with segregated ballast tanks, and improved treatment-facility efficiency in removing PAH. From the 2018 collections, mussel-tissue hydrocarbon concentrations from all eleven LTEMP stations (within Port Valdez as well as PWS and NGOA regions) were below method detection limits and similar to laboratory blanks (TPAH43 < 44 ng/g dry wt.). At these low background levels, elevated TPAH values from a minor 2020 spill incident at the Terminal were easily detected at all three Port Valdez stations.

First Detection of Paralytic Shellfish Toxins from Alexandrium pacificum above the Regulatory Limit in Blue Mussels (Mytilus galloprovincialis) in New South Wales, Australia

In 2016, 2017 and 2018, elevated levels of the species Alexandrium pacificum were detected within a blue mussel (Mytilus galloprovincialis) aquaculture area at Twofold Bay on the south coast of New South Wales, Australia. In 2016, the bloom persisted for at least eight weeks and maximum cell concentrations of 89,000 cells L−1 of A. pacificum were reported. The identity of A. pacificum was confirmed using molecular genetic tools (qPCR and amplicon sequencing) and complemented by light and scanning electron microscopy of cultured strains. Maximum reported concentrations of paralytic shellfish toxins (PSTs) in mussel tissue was 7.2 mg/kg PST STX equivalent. Elevated cell concentrations of A. pacificum were reported along the adjacent coastal shelf areas, and positive PST results were reported from nearby oyster producing estuaries during 2016. This is the first record of PSTs above the regulatory limit (0.8 mg/kg) in commercial aquaculture in New South Wales since the establishment of routine biotoxin monitoring in 2005. The intensity and duration of the 2016 A. pacificum bloom were unusual given the relatively low abundances of A. pacificum in estuarine and coastal waters of the region found in the prior 10 years.

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).

A Validated Routine Method for Butyltin Determination in Seafood by Gas Chromatography Inductively Coupled Plasma Isotope Dilution Mass Spectrometry

Organotin compounds are anthropogenic metal species with multiple uses as pesticides, preservatives, antifouling agents, biocides, and catalysts. Butyltins are the main organotin compounds found in biota, and the highest levels are found in marine foodstuffs. In this paper, we present the figures of merit for an in-house validated method for routine analysis of butyltins in seafood using GC inductively coupled plasma isotope dilution MS. The working range of the method spanned several orders of magnitude from 3.3–1013, 2.4–785, and 0.3–900 ng Sn/g dry weight for monobutyltin (MBT), dibutyltin (DBT), and tributyltin (TBT), respectively. The trueness of the method was evaluated by analyzing Certified Reference Materials (CRMs) ERM CRM 477 (Mussel Tissue) and NIES CRM 15 (Scallop). Recoveries, with RSD % in parentheses, were 78 (±14), 80 (±6), and 88% (±8%) for MBT, DBT, and TBT in ERM CRM 477 and 96% (±5%) for TBT in NIES CRM 15. Good agreements were found between experimental uncertainties and uncertainties predicted for single-laboratory validated methods calculated from the maximum standard measurement uncertainty function. The method has proven to be robust, and the wide range of seafood validated ensures that the method is applicable for measuring butyltins in marine tissue.