Assessment of microplastic presence in coastal environments and organisms of Da Nang, Vietnam.

This study investigates the presence of microplastics (MPs) in seawater, sediments, and organisms along the coastal areas of Da Nang, Vietnam. The results obtained revealed MP concentrations ranging from 111 to 304 MPs/L in seawater and 2267 to 4600 MPs/kg in sediment. In organisms such as oysters, mussels, crabs, snails, and fish, MP levels ranged from 1.8 to 17.3 MPs/g (wet weight). Fiber MPs were found to be predominant across seawater, sediment, and organisms. The study identified eight, ten, and eleven types of MPs in seawater, sediment, and organisms, respectively, with Nylon, Polytetrafluoroethylene (PTFE), and Ethylene vinyl alcohol (EVOH) being the most prevalent. Notably, MP concentrations were significantly higher in benthic organisms such as oysters, mussels, and crabs compared to fish (t-test, p < 0.05), suggesting habitat dependency. Similar concentrations, shapes, and types of MPs in seawater, sediments, and organisms demonstrate a tendency for MP accumulation in aquatic organisms within the marine environment.

Toxicology assessment of deep-sea mining impacts on Gigantidas platifrons: A comparative in situ and laboratory metal exposure study.

Deep-sea toxicology is essential for deep-sea environmental impact assessment. Yet most toxicology experiments are conducted solely in laboratory settings, overlooking the complexities of the deep-sea environment. Here we carried out metal exposure experiments in both the laboratory and in situ, to compare and evaluate the response patterns of Gigantidas platifrons to metal exposure (copper [Cu] or cadmium [Cd] at 100 µg/L for 48 h). Metal concentrations, traditional biochemical parameters, and fatty acid composition were assessed in deep-sea mussel gills. The results revealed significant metal accumulation in deep-sea mussel gills in both laboratory and in situ experiments. Metal exposure could induce oxidative stress, neurotoxicity, an immune response, altered energy metabolism, and changes to fatty acid composition in mussel gills. Interestingly, the metal accumulating capability, biochemical response patterns, and fatty acid composition each varied under differing experimental systems. In the laboratory setting, Cd-exposed mussels exhibited a higher value for integrated biomarker response (IBR) while in situ the Cu-exposed mussels instead displayed a higher IBR value. This study emphasizes the importance of performing deep-sea toxicology experiments in situ and contributes valuable data to a standardized workflow for deep-sea toxicology assessment.

Human health risks assessment of the fluctuations in mercury levels in seafood from different key regions of Rio de Janeiro, Brazil.

Mercury (Hg) contamination on the Brazilian southeast coast has been highlighted, especially in relation to species of commercial importance. This study aimed to quantify the Hg concentration in species of mussels, fish, and crabs obtained from fishing colonies on the beaches of the west and south of the city of Rio de Janeiro, investigate the possible effect of seasonality, sex, and location sampling, and finally, the risk to consumer health in four different age groups. The difference between cooked and raw commercially available mussel samples was also verified. The main results highlight that the fish presented higher levels of Hg and that the mussel samples sold cooked presented lower levels of Hg when compared to the raw ones. For Micropogonias furnieri, Sardinella brasiliensis, and Callinectes spp., the season variable influenced Hg concentrations, while only for Merluccius merluccius was a difference between the sexes identified, with males having the highest values. Although Hg concentrations in animals were below the permitted limit, consumption of all species exceeded the monthly intake limit for this metal. For the hazard quotient (HQ) calculation, most species presented HQ > 1, especially when ingested by the child population. These results are fundamental for designing consumption strategies for these animals, in order to prioritize the acquisition of some species over others, depending on the location and/or season, for each age group, with the aim of maintaining seafood consumption with minimal risk to the population's health.

An assessment and characterization of pharmaceuticals and personal care products (PPCPs) within the Great Lakes Basin: Mussel Watch Program (2013-2018).

Defining the environmental occurrence and distribution of chemicals of emerging concern (CECs), including pharmaceuticals and personal care products (PPCPs) in coastal aquatic systems, is often difficult and complex. In this study, 70 compounds representing several classes of pharmaceuticals, including antibiotics, anti-inflammatories, insect repellant, antibacterial, antidepressants, chemotherapy drugs, and X-ray contrast media compounds, were found in dreissenid mussel (zebra/quagga; Dreissena spp.) tissue samples. Overall concentration and detection frequencies varied significantly among sampling locations, site land-use categories, and sites sampled proximate and downstream of point source discharge. Verapamil, triclocarban, etoposide, citalopram, diphenhydramine, sertraline, amitriptyline, and DEET (N,N-diethyl-meta-toluamide) comprised the most ubiquitous PPCPs (> 50%) detected in dreissenid mussels. Among those compounds quantified in mussel tissue, sertraline, metformin, methylprednisolone, hydrocortisone, 1,7-dimethylxanthine, theophylline, zidovudine, prednisone, clonidine, 2-hydroxy-ibuprofen, iopamidol, and melphalan were detected at concentrations up to 475 ng/g (wet weight). Antihypertensives, antibiotics, and antidepressants accounted for the majority of the compounds quantified in mussel tissue. The results showed that PPCPs quantified in dreissenid mussels are occurring as complex mixtures, with 4 to 28 compounds detected at one or more sampling locations. The magnitude and composition of PPCPs detected were highest for sites not influenced by either WWTP or CSO discharge (i.e., non-WWTPs), strongly supporting non-point sources as important drivers and pathways for PPCPs detected in this study. As these compounds are detected at inshore and offshore locations, the findings of this study indicate that their persistence and potential risks are largely unknown, thus warranting further assessment and prioritization of these emerging contaminants in the Great Lakes Basin.

Assessment of Gastroenteric Viruses in Marketed Bivalve Mollusks in the Tourist Cities of Rio de Janeiro, Brazil, 2022.

This study investigated the prevalence and genetic diversity of gastroenteric viruses in mussels and oysters in Rio de Janeiro, Brazil. One hundred and thirty-four marketed bivalve samples were obtained between January and December 2022. The viral analysis was performed according to ISO/TS 15216, and the screening revealed the detection of norovirus GII/GI (40.3%), sapovirus (SaV; 12.7%), human mastadenovirus (7.5%), and rotavirus A (RVA; 5.9%). In total, 44.8% (60) of shellfish samples tested positive for one or more viruses, 46.7% (28/60) of the positive samples tested positive for a single viral agent, 26.7% (16) tested positive for two viral agents, 8.3% (5) for three viral agents, and 13.3% (8) for four viral agents. Additionally, three mussel samples were contaminated with the five investigated viruses (5%, 3/60). Norovirus GII showed the highest mean viral load (3.4 × 105 GC/g), followed by SaV (1.4 × 104 GC/g), RVA (1.1 × 104 GC/g), human mastadenovirus (3.9 × 103 GC/g), and norovirus GI (6.7 × 102 GC/g). Molecular characterization revealed that the recovered norovirus strains belonged to genotypes GII.2, GII.6, GII.9, GII.17, and GII.27; SaV belonged to genotypes GI.1 and GIV.1; RVA to genotypes G6, G8, P[8]-III, and human mastadenovirus to types F40 and F41. The GII.27 norovirus characterized in this study is the only strain of this genotype reported in Brazil. This study highlights the dissemination and diversity of gastroenteric viruses present in commercialized bivalves in a touristic area, indicating the potential risk to human health and the contribution of bivalves in the propagation of emerging pathogens.

Contamination Status and Risk Assessment of Paralytic Shellfish Toxins in Shellfish along the Coastal Areas of China.

Paralytic shellfish toxins (PSTs) are widely distributed in shellfish along the coast of China, causing a serious threat to consumer health; however, there is still a lack of large-scale systematic investigations and risk assessments. Herein, 641 shellfish samples were collected from March to November 2020, and the PSTs' toxicity was detected via liquid chromatography-tandem mass spectrometry. Furthermore, the contamination status and potential dietary risks of PSTs were discussed. PSTs were detected in 241 shellfish samples with a detection rate of 37.60%. The average PST toxicities in mussels and ark shells were considerably higher than those in other shellfish. The PSTs mainly included N-sulfonylcarbamoyl toxins (class C) and carbamoyl toxins (class GTX), and the highest PST toxicity was 546.09 µg STX eq. kg-1. The PST toxicity in spring was significantly higher than those in summer and autumn (p < 0.05). Hebei Province had the highest average PST toxicity in spring. An acute exposure assessment showed that consumers in Hebei Province had a higher dietary risk, with mussels posing a significantly higher dietary risk to consumers. This research provides reference for the green and sustainable development of the shellfish industry and the establishment of a shellfish toxin prevention and control system.

Microplastic in clams: An extensive spatial assessment in south Brazil.

Microplastic pollution is becoming a continuously growing environmental concern, while bivalve mollusks are particularly vulnerable due to their sessile habits and feeding through water filtration processes. Microplastic incidence in soft tissues of the clam Amarilladesma mactroides was assessed along unconsolidated substrates distributed in extensive coastal regions of southern Brazil. Influence of urbanization levels, distance to rivers and local hydrodynamics on microplastic accumulation by the clam was tested. The average concentration of microplastics was high (3.09 ± 2.11 particles.g-1), considering 16 sampled sites. Particles were mainly composed by polyamide, polyethylene and polyethylene terephthalate, while were mainly smaller, fibrous and colorless. High urbanization and closer proximity to rivers insured higher contamination, which is a trend observed globally. No influence of coastal hydrodynamics was seen. Considering obtained findings, A. mactroides presents good potential to be used as a valuable tool to assess microplastic contamination in unconsolidated substrates of beach areas.

Comprehensive analysis and assessment of exposure to enteric viruses and bacteria in shellfish.

Shellfish species, including oysters, clams, and mussels, are extensively cultured in coastal waters. Its location is determined by factors such as nutrient availability, water temperature, tidal cycle, and the presence of contaminants such as Escherichia coli and enteric viruses. With the expansion and intensification of human activities at vicinities, the presence of anthropogenic contaminants has increased, threatening shellfish farms and consumer safety give the prevalent consumption of raw shellfish. This literature review aims to provide a comprehensive analysis of the dietary exposure and assess the risk associated with enteric viruses and bacteria detected in shellfish. The predominant bacteria and viruses detected in shellfish are reported, and the potential interrelation is discussed. The main characteristics of each contaminant and shellfish were reviewed for a more comprehensive understanding. To facilitate a direct estimation of exposure, the estimated daily intake (EDI) of bacteria was calculated based on the average levels of E. coli in shellfish, as reported in the literature. The mean daily ingestion of seafood in each of the five continents was considered. Asia exhibited the highest intake of contaminants, with an average of ±5.6 E. coli units/day.kg body weight in cockles. Simulations were conducted using recommended shellfish consumption levels established by state agencies, revealing significantly lower (p < 0.01) EDI for all continents compared to estimations based on recommended levels. This indicates a higher risk associated with healthy shellfish ingestion, potentially leading to increased intoxication incidents with a change in dietary habits. To promote a healthier lifestyle through increased shellfish consumptions, it is imperative to reduce the exposure of shellfish species to bacteria and enteric viruses. The conventional use of E. coli as the sole indicator for consumption safety and water quality in shellfish farms has been deemed insufficient. Instances where shellfish met E. coli limits established by state agencies were often found to be contaminated with human enteric viruses. Therefore, a holistic approach considering the entire production chain is necessary to support the shellfish industry and ensure food safety.

Assessment of the health risks associated with the consumption of bivalve mollusks potentially contaminated with phycotoxins from the coastal ecosystem of the Ebrié lagoon, Côte d'Ivoire.

This work focused on assessing of the risk associated with the consumption of bivalve mollusks, potentially contaminated with phycotoxins. The studied phycotoxins are saxitoxin (STX), okadaic acid (OA), dinophysistoxins (DTXs), yessotoxins (YTXs), pectenotoxins (PTX), azaspiracids (AZAs), and domoic acid (DA). These toxins were investigated in three species of bivalve mollusks (Anadara senilis, Crassostrea gasar, and Perna perna), originating from the Ebrié lagoon. Chemical analyses were carried out by LC-MS/MS, HPLC-FLD, and HPLC-UV. The level of OA and DTXs, STX, and DA was 10.92 µg OA eq./kg, 9.6 µg STX eq./kg, and 0.17 mg DA eq./kg, respectively. The level of PTXs and AZAs was 3.3 µg PTX-2 eq./kg and 13.86 µg AZA-1 eq./kg; that of YTXs was 0.01 mg YTX eq./kg. The daily exposure dose (DED) was 0.019 µg OA eq./kg bw for OA and DTXs; 0.285 µg DA eq./kg bw for DA; 0.006 µg PTX-2 eq./kg bw for PTXs; 0.016 µg STX eq./kg bw for STX; 0.01 µg YTX eq./kg bw for YTXs; and 0.024 µg AZA-1 eq./kg bw for AZAs for the oyster Crassostrea gasar. These estimated values are lower than the acute reference dose (ARfD) of each phycotoxin recommended by the European Food Safety Agency (EFSA). The risk of harmful effects is acceptable. The absence of risk is valid only for the study period (11 months) and concerns coastal populations living near the sampling points.

Radiological hazard assessment of 210Po in freshwater mussels (Sinanodonta jourdyi) and golden apple snail (Pomacea canaliculata) in Vietnam.

210Po is a significant source of ionizing radiation that people are exposed to through food globally. This paper presents the wide range of accumulation level of 210Po in the organs of two species of shellfish including freshwater mussel (Sinanodonta jourdyi) and golden apple snail (Pomacea canaliculata), common freshwater species in Vietnam. There was a significant correlation between 210Po activity in muscle to their mass and size of freshwater mussels. In contrast, there was no relation between other organs of both species with their mass and size. The annual effective dose due to consumption of freshwater mussels ranged from 68.7 to 291 µSv year-1 with a mean value of 138 µSv year-1 for muscle and from 321 to 4560 µSv year-1 with a mean value of 1422 µSv year-1 for the hepatopancreas. Meanwhile, the AED for golden apple snail was recorded to be higher with values ranging from 105 to 2189 µSv year-1 with mean value of 673 µSv year-1 for muscle and from 468 to 4155 µSv year-1 with a mean value of 2332 µSv year-1 for hepatopancreas. Thus, the consumption of these two types of shellfish is considered relatively safe, but the hepatopancreas gland must be removed before processing.

Assessing shorebird mortalities due to razor clam aquaculture at key migratory stopover sites in southeastern China.

Aquaculture can provide foraging habitat for birds, but it can also result in intentional and accidental mortality. We examined an overlooked conflict between razor clam (Sinonovacula spp.) aquaculture and declining shorebirds in southeastern China's Fujian and Zhejiang provinces. We surveyed 6 out of 11 internationally important stopover sites for these shorebirds and monitored shorebird mortality in 2 sites (Xinghua Bay, Yueqing Bay) with razor clam aquaculture. We visited an additional 32 sites in these 2 provinces to determine if there was netting in other razor clam farms. Approximately 8-9 km2 of intertidal foraging habitat was covered by horizontal nets to prevent birds from feeding on young razor clams at Xinghua Bay and Yueqing Bay. We conservatively estimated that 13,676 (2.5th-97.5th percentile 8,330-21,285) individual shorebirds were entangled in the nets at the 2 monitored sites in April and May 2021, including 2 endangered and 7 near-threatened species. Mortality of 5 species for which we had sufficient data accounted for 0.76% (black-tailed godwit [Limosa limosa]) to 4.27% (terek sandpiper [Xenus cinereus]) of their total flyway populations. This level of mortality could strongly affect their populations. We found netting at 17 additional razor clam farms, indicating a widespread threat to shorebirds. Although razor clams are typically harvested in late March to early April, nets are left on the mudflats throughout the spring and summer, including when the bulk of shorebird migration takes place. Immediately removing these nets after the clam harvest could prevent most of the spring mortality of shorebirds, although this is unlikely to happen without government regulations or economic incentives. To better assess and mitigate the impacts of this conflict, future research should quantify shorebird mortality at other razor clam farms, including during winter, explore less harmful deterrence methods, and assess the socioeconomic factors driving the conflict.

Evaluación de la mortalidad de aves costeras causada por la acuacultura de almejas navaja en sitios importantes de descanso migratorio en el sureste de China Resumen La acuacultura puede proporcionar hábitats de forrajeo para las aves, pero también puede derivar en muertes accidentales o intencionales. Analizamos un conflicto ignorado entre la acuacultura de almeja navaja (Sinonovacula spp.) y la declinación de aves costeras en las provincias de Fujian y Zhejiang del sureste de China. Censamos seis de los once sitios de descanso con importancia internacional para estas aves y monitoreamos su mortalidad en dos sitios en donde se cría la almeja navaja: la bahía de Xinghua y la de Yueqing. Además, visitamos 32 sitios en estas dos provincias para determinar si existían redes en otras granjas de almeja navaja. Unos 8 ­ 9 km2 del hábitat intermareal de forrajeo estaban cubiertos por redes horizontales para evitar que las aves se alimentaran de las almejas juveniles en ambas bahías. Estimamos moderadamente que 13,676 (2.5° ­ 97.5° percentil 8,330 ­ 21,285) individuos de aves costeras se enredaron en las redes en los dos sitios monitoreados durante abril y mayo de 2021, incluyendo a dos especies en peligro y siete casi amenazadas. La mortalidad de las cinco especies para las cuales tuvimos suficientes datos representó del 0.76% (Limosa limosa) al 4.27% (Xenus cinereus) del total de las poblaciones migratorias. Este nivel de mortalidad podría tener un gran efecto sobre las poblaciones de estas especies. Encontramos redes en 17 granjas más, lo que indica una amenaza extendida para las aves costeras. Aunque es típico que se colecte la almeja navaja a finales de marzo y principios de abril, las redes permanecen durante toda la primavera y el verano, incluso cuando ocurre la mayoría de los vuelos migratorios. La eliminación inmediata de estas redes después de la colecta de almejas podría prevenir la mayoría de las muertes primaverales de las aves costeras, aunque no es probable que esto suceda sin regulaciones gubernamentales o incentivos económicos. Para tener mejores evaluaciones y mitigaciones del impacto de este conflicto, una investigación más profunda debería cuantificar la mortalidad de las aves costeras en otras granjas, incluso durante el invierno, explorar métodos de disuasión menos dañinos y evaluar los factores socioeconómicos que causan el conflicto.

The assessment of bioavailability and environmental risk of dissolved and particulate polycyclic aromatic hydrocarbons in the seawater of typical bays.

The pollution of dissolved and particulate polycyclic aromatic hydrocarbons (PAHs) in coastal waters has been increasing in recent decades. However, limited research has been conducted on the characteristics of dissolved and particulate PAHs in seawater and their associated risk assessment. Here, we focused on the bioavailability and environmental risk of PAHs in four typical bays of Shandong Province, China, and used scallop Chlamys farreri and clam Mactra veneriformis as sentinel species. The results revealed that dissolved PAHs tended to bioaccumulate in scallop C. farreri, and their ecological risk exhibited a significant correlation with the health risk of bioaccumulated PAHs and the bioeffect of screened biomarkers in scallop. Conversely, particulate PAHs demonstrated a higher bioaccumulation potential in the clam M. veneriformis, showing a stronger correlation between their ecological risk, health risk, and bioeffect in clams. This study provides the first elucidation of the connection between the ecological risk, health risk, and bioeffect of PAHs. Furthermore, based on the better correlation of health risk and bioeffect caused by PAHs with total PAHs in seawater, we propose that the clam M. veneriformis is a more suitable sentinel species for assessing environmental risk in typical bays of Shandong Province.

Detection of paralytic shellfish toxins by near-infrared spectroscopy based on a near-Bayesian SVM classifier with unequal misclassification costs.

BACKGROUND: Paralytic shellfish poisoning caused by human consumption of shellfish fed on toxic algae is a public health hazard. It is essential to implement shellfish monitoring programs to minimize the possibility of shellfish contaminated by paralytic shellfish toxins (PST) reaching the marketplace. RESULTS: This paper proposes a rapid detection method for PST in mussels using near-infrared spectroscopy (NIRS) technology. Spectral data in the wavelength range of 950-1700 nm for PST-contaminated and non-contaminated mussel samples were used to build the detection model. Near-Bayesian support vector machines (NBSVM) with unequal misclassification costs (u-NBSVM) were applied to solve a classification problem arising from the fact that the quantity of non-contaminated mussels was far less than that of PST-contaminated mussels in practice. The u-NBSVM model performed adequately on imbalanced datasets by combining unequal misclassification costs and decision boundary shifts. The detection performance of the u-NBSVM did not decline as the number of PST samples decreased due to adjustments to the misclassification costs. When the number of PST samples was 20, the G-mean and accuracy reached 0.9898 and 0.9944, respectively. CONCLUSION: Compared with the traditional support vector machines (SVMs) and the NBSVM, the u-NBSVM model achieved better detection performance. The results of this study indicate that NIRS technology combined with the u-NBSVM model can be used for rapid and non-destructive PST detection in mussels. © 2023 Society of Chemical Industry.

Occurrence and risk assessment of okadaic acid, dinophysistoxin-1, dinophysistoxin-2, and dinophysistoxin-3 in seafood from South Korea.

The okadaic acid (OA)-group toxins, including OA, dinophysistoxin-1 (DTX1), dinophysistoxin-2 (DTX2), and dinophysistoxin-3 (DTX3), cause diarrheic shellfish poisoning in humans. To manage OA-group toxins more strictly, Korean regulations were recently revised to consider OA, DTX1, DTX2, and DTX3 combined. Thus, our study characterized the occurrence of OA, DTX1, DTX2, and DTX3 in seafood distributed across South Korea, and a risk assessment of seafood consumption was conducted. Two hundred and seventeen samples from 16 bivalve and 7 non-bivalve species collected from three representative coastal areas in 2021 were analyzed via liquid chromatography-tandem mass spectrometry. OA, DTX1, and DTX3 were detected in 2.3%, 4.1%, and 9.2% of the examined samples, with positive mean levels of 11.3, 16.4, and 40.9 µg/kg, respectively. DTX2 was not detected in any of the samples. At least one OA-group toxin was detected in the bivalve samples, including blood clams, pan shells, hard clams, mussels, and scallops, whereas none were detected in non-bivalves. The estimated acute exposure to OA-group toxins through the intake of seafood in the Korean population and consumer groups was low, ranging from 24.7 to 74.5% of the recommended acute reference dose (ARfD) of 0.33 µg OA equivalents/kg body weight. However, for the scallop consumers aged 7-12 years, acute exposure to OA-group toxins exceeded the ARfD, indicating a possible health risk. These results suggest that including DTX3 in the new regulatory limits is appropriate to protect Korean seafood consumers from exposure to OA-group toxins.

A Weight of Evidence approach to support the assessment of the quality of Manila clam farming sites in a coastal lagoon.

Aquaculture productivity in coastal lagoons is endangered by a complex interplay of anthropogenic and environmental factors, amplified by the effects of climate change in these sensitive areas. To reach a more comprehensive assessment of farming sites quality, a quantitative Weight of Evidence approach (QWoE) is applied for the first time to data collected at four Manila clam (R. philippinarum) farming sites in the Venice lagoon (Italy). This included sediment quality, chemical bioaccumulation, and biological responses. Results revealed a greater hazard for sites closer to the open sea. In these areas, the combination of sediment characteristics and a higher frequency of salinity and temperature stress could explain the alterations measured at a transcriptional and biomarker level. The findings demonstrate that a QWoE approach that integrates multiple sources of evidence should also include physicochemical conditions in order to better understand the impacts of human activities and other stressors on clam aquaculture productivity.

An Occurrence and Exposure Assessment of Paralytic Shellfish Toxins from Shellfish in Zhejiang Province, China.

The intake of paralytic shellfish toxins (PSTs) may adversely affect human health. Therefore, this study aimed to show the prevalence of PSTs from commercially available shellfish in Zhejiang Province, China, during the period of frequent red tides, investigate the factors affecting the distribution of PSTs, and assess the risk of PST intake following the consumption of bivalve shellfish among the Zhejiang population. A total of 546 shellfish samples were collected, 7.0% of which had detectable PSTs at concentrations below the regulatory limit. Temporal, spatial, and interspecific variations in the occurrence of PSTs were observed in some cases. The dietary exposure to PSTs among the general population of consumers only was low. However, young children in the extreme scenario (the 95th percentile of daily shellfish consumption combined with the maximum PST concentration), defined as 89-194% of the recommended acute reference doses, were possibly at risk of exposure. Notably, Arcidae and mussels were the major sources of exposure to toxins. From the public health perspective, PSTs from commercially available shellfish do not pose a serious health risk; however, more attention should be paid to acute health risks, especially for young children, during periods of frequent red tides.

Microplastic accumulation in bivalves collected from different coastal areas of Vietnam and an assessment of potential risks.

Microplastic (MP) pollution is an emerging problem in many areas around the world and in coastal areas of Vietnam, requiring more studies dedicated to the accumulation of this pollutant in the food chain as well as its potential risk to human health. This study investigated MP levels in tissues of five common bivalve species collected from aquaculture areas along the coast of Vietnam. MPs were found in all bivalve samples, with average values of 10.84 ± 2.61 items/individual or 2.40 ± 1.34 items/g wet weight. Impacts of feeding habits of bivalves showed influences on MP abundance in the samples. Fibers were the dominant shape of MPs recorded, most of which accumulated in the gills and digestive glands of all bivalve samples, with the majority falling within the size range of 300-2000 µm. MPs found in all studied species had relatively similar chemical compositions, mainly composed of polypropylene (PP) and polyethylene (PE). In this study, a diverse diet consisting of different bivalve species and detailed data on the consumption rate of these species were used to assess the human health risk of MPs dedicated to the coastal communities of Vietnam. The results suggested a significant part of MP uptake by human could be via bivalve consumption, in which removing viscera and proper depuration should be applied prior to eating, thereby reducing the risk.

Valuing bioeconomic impacts of regulation on nutrient loads mediated by invasive mussels in Lake Michigan.

Current calls to correct the perturbed ecosystems and nutrient imbalances of the Laurentian Great Lakes focus on setting target nutrient levels that will be met by environmental and economic regulations to reduce the flow of excess nutrients into the lakes. While these standard types of regulations have been successful in the past, it is unclear whether they will achieve similar ecological and economic successes now amid possible ecosystem regime shifts triggered by invasive mussels. We compute the bioeconomic costs and benefits of hypothetical regulations designed to target nutrient loads in present-day Lake Michigan through agricultural operations, which are known to be nonpoint source polluters of the aquatic ecosystem network. Our results show how reducing nutrient loads may exacerbate spatially disparate ecosystem issues that generate overall economic losses. Conversely, and counterintuitively, allowing for more nutrient loading could generate economic gains over our assessment timeframe. We determine that implementation of standard nutrient target policies are costly and likely inadequate for current dreissenid-affected aquatic ecosystems experiencing nutrient imbalances because they disregard the interactive role of invasive mussels in nutrient cycling.

Toxicity assessment and detoxification metabolism of sodium pentachlorophenol (PCP-Na) on marine economic species: a case study of Moerella iridescens and Exopalaemon carinicauda.

Sodium pentachlorophenol (PCP-Na) is widespread in the marine environment; however, its impact on marine organisms remains under-researched. Moerella iridescens and Exopalaemon carinicauda are marine species of economic importance in China and under threat from PCP-Na pollution. Thus, this study aimed to assess the toxicity and detoxification metabolism of PCP-Na on M. iridescens and E. carinicauda. The study revealed that the 96 h median lethal concentration (LC50) of PCP-Na for M. iridescens and E. carinicauda were 9.895 mg/L and 14.143 mg/L, respectively. A species sensitivity distribution (SSD) for PCP-Na was developed specifically for marine organisms, determining a hazardous concentration to 5% of the species (HC5) of 0.047 mg/L. During the sub-chronic exposure period, PCP-Na accumulated significantly in M. iridescens and E. carinicauda, with highest concentrations of 41.22 mg/kg in the soft tissues of M. iridescens, 42.58 mg/kg in the hepatopancreas of E. carinicauda, and only 0.85 mg/kg in the muscle of E. carinicauda. Furthermore, the study demonstrated that detoxifying metabolic enzymes and antioxidant defense system enzymes of E. carinicauda responded stronger to PCP-Na compared to M. iridescens, suggesting that E. carinicauda may possess a stronger detoxification capacity. Notably, five biomarkers were identified and proposed for monitoring and evaluating PCP-Na contamination. Overall, the results indicated that M. iridescens and E. carinicauda exhibit greater tolerance to PCP-Na than other marine species, but they are susceptible to accumulating PCP-Na in their tissues, posing a significant health risk. Consequently, conducting aquatic health risk assessments in areas with potential PCP-Na contamination is strongly recommended.

Consumption of Bivalve Shellfish in French Coastal Populations: Data for Acute and Chronic Exposure Assessment.

Shellfish are a source of nutrients but are also a matter of concern in terms of food safety due to natural contaminants such as phycotoxins or anthropogenic contaminants including microbial agents and heavy metals. However, data related to consumption for each mollusk species are scarce and missing for appropriate exposure calculation. The objective of the study was to generate shellfish consumption data in the adult coastal population in France to assess exposure to health risks, the effects of determinants on the frequency of consumption and usual intake, and shellfish food risk perception. Our study, named the CONSOMER study, was carried out using an online survey in 2016 and 2017 and included a food frequency questionnaire. After validation, 2,479 individual questionnaires were available for statistical analysis. Our findings provide estimates of shellfish consumption frequency, portion sizes, weekly intake in g/week, and g/week/body weight that can be used for acute and chronic exposure calculations. For the acute risk, the 97.5th percentile of the portion size was found to be around 290 g for the adult coastal population. For chronic exposure, recreational shellfish harvesting activities were associated with higher weekly intakes. A non-negligible part of this subpopulation is not aware of food safety recommendations concerning harvesting areas. Results for shellfish harvester consumption in particular are consistent with other available data. Exposure calculations and safety recommendations should target shellfish harvesters.