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The consumption of seafood is crucial for food security, but poor hygiene along the food production chain can result in low microbiological quality, posing significant risks for public health and seafood quality. Thus, this study aimed to assess the microbiological quality and antimicrobial sensitivity of E. coli from 69 samples of illegally marketed shrimp and mussels in the Vitória Region, Brazil. These foods exhibited poor microbiological quality due to high counts of mesophilic, psychrotrophic, and enterobacteria microorganisms. While this issue is widespread in this area, shrimp samples displayed higher microbial counts compared to mussels, and fresh mussels had elevated counts of enterobacteria compared to frozen ones. Among the 10 E. coli isolates, none carried the genes blaCTX-M-1, blaCTX-M-2, blaCTX-M-3, blaCTX-M-15, mcr-1, mcr-2, mcr-3, mcr-4, and tet, associated with antibiotic resistance. Phenotypical resistance to tetracycline and fosfomycin was not observed in any isolate, while only 20% demonstrated resistance to ciprofloxacin. Regarding ampicillin and amoxicillin with clavulanic acid, 60% of isolates were resistant, 10% showed intermediate susceptibility, and 30% were sensitive. One isolate was considered simultaneously resistant to ß-lactams and quinolones, and none were conserved as ESBL producers. These findings highlight the inherent risks to local public health that arise from consuming improperly prepared seafood in this area.

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The study of marine toxins in shellfish is of the utmost importance to ensure people's food safety. Marine toxins in shellfish and microalgae in the water column off the south-central coast of Chile (36°â€’43° S) were studied in a network of 64 stations over a 14-month period. The relative abundance of harmful species Alexandrium catenella, Alexandrium ostenfeldii, Protoceratium reticulatum, Dinophysis acuminata, Dinophysis acuta, Pseudo-nitzschia seriata group and P. delicatissima group was analyzed. The detection and quantification of lipophilic toxins and domoic acid (DA) in shellfish was determined by UHPLC-MS/MS, and for Paralytic Shellfish Toxins (PSTs) by HPLC-FD with post-column oxidation, while for a culture of A. ostenfeldii a Hylic-UHPLC-MS/MS was used. Results showed that DA, gonyautoxin (GTX)-2, GTX-3 and pectenotoxin (PTX)-2 were detected below the permitted limits, while Gymnodimine (GYM)-A and 13-desmethylespirolide C (SPX-1) were below the limit of quantitation. According to the distribution and abundance record of microalgae, DA would be associated to P. seriata and P. delicatissima-groups, PTX-2 to D. acuminata, and GTX-2, GTX-3, GYM-A, and SPX-1 to A. ostenfeldii. However, the toxin analysis of an A. ostenfeldii culture from the Biobío region only showed the presence of the paralytic toxins C2, GTX-2, GTX-3, GTX-5 and saxitoxin, therefore, the source of production of GYM and SPX is still undetermined.

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Alexandrium tamiyavanichii is a marine dinoflagellate known to produce Paralytic Shellfish Poisoning (PSP) toxin. Thus, a strain was isolated from La Paz Bay, Baja California Sur, Mexico and used to explore whether stress conditions, such as phosphorus limitation (PL) and nitrogen enrichment (NE) modulate population growth and PSP toxin production in the GSe medium. Growth kinetics showed that the PL treatment produced a 3.4-fold increase in cell density versus control at day 30 of the culture cycle. The highest PSP concentration was found in the control culture (309 fmol cell-1) on day 21. Saxitoxin (STX) was the main analog in all the treatments (> 40 % mol). In conclusion, PL and NE treatments promoted growth kinetics in the species studied but did not affect the PSP toxin production. For the first time, the present research describes A. tamiyavanichii high toxicity strain isolated from Mexican coasts relative to the South-Atlantic strains.

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Harmful algal blooms (HABs) can produce a variety of noxious effects and, in some cases, the massive mortality of wild and farmed marine organisms. Some HAB species produce toxins that are released into seawater or transferred via food webs (particulate toxin fraction). The objective of the present study was to identify the toxicological effects of subacute exposure to saxitoxin (STX) during embryonic and early larval stages in Seriola rivoliana. Eggs were exposed to dissolved 19 STX (100 µg L-1). The toxic effects of STX were evaluated via the hatching percentage, the activity of three enzymes (protein and alkaline phosphatases and peroxidase), and the expression of four genes (HSF2, Nav1.4b, PPRC1, and DUSP8). A low hatching percentage (less than 5%) was observed in 44 hpf (hours post fertilization) embryos exposed to STX compared to 71% in the unexposed control. At this STX concentration, no oxidative stress in the embryos was evident. However, STX induced the expression of the NaV1.4 channel α-subunit (NaV1.4b), which is the primary target of this toxin. Our results revealed the overexpression of all four candidate genes in STX-intoxicated lecithotrophic larvae, reflecting the activation of diverse cellular processes involved in stress responses (HSF2), lipid metabolism (PPRC1), and MAP kinase signaling pathways associated with cell proliferation and differentiation (DUSP8). The effects of STX were more pronounced in young larvae than in embryos, indicating a stage-specific sensitivity to the toxin.

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The frequency of harmful algal blooms (HABs) has increased over the last two decades, a phenomenon enhanced by global climate change. However, the effects of climate change will not be distributed equally, and Chile has emerged as one important, vulnerable area. The Chilean Patagonian region (41‒56°S) hosts two marine ecoregions that support robust blue economies via wild fisheries, aquaculture, and tourism. However, the harmful algal bloom-forming dinoflagellate Alexandrium catenella, a causative agent of paralytic shellfish poisoning outbreaks, threatens the viability of blue industries in this region and others worldwide. Despite the proliferation of A. catenella blooms over the last few decades, the role of sedimentary resting cysts in the recurrence of harmful algal blooms and the species' northward expansion across Chilean Patagonia is not well understood. As a resting cyst-producing species, the sediment-cyst dynamics of A. catenella likely contribute to the geographical expansion and bloom recurrence of this species. For this purpose, we analyzed a decade of A. catenella surface sediment cyst records across the two ecoregions of the Chilean Patagonian System that were further stratified into five subregions based on water temperature, salinity, dissolved oxygen, and nutrient characteristics. We also analyzed spatio-temporal cyst dynamics in a pre-, during-, and post-bloom scenario of the Chiloense ecoregion (more northern) of the Magellanic province. Our results indicated highly variable A. catenella resting cyst abundances, with a maximum of 221 cysts cm-3 recorded in 2002 after an intense bloom. Generalized linear mixed models and linear mixed models found that sampling season, subregion, and Total Organic Matter (%) explained resting cyst presence and density. The results also demonstrated the presence of A. catenella cysts in northern subregions, evidencing the northward geographical expansion observed during the last few decades. The risks of A. catenella bloom recurrence from small, patchy resting cyst distributions across broad geographical areas and under changing environmental conditions are discussed.

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In seafood, the study of metal(loid)s is essential to assess their toxicity and to establish risks of human exposure. This study investigates the content of As, Cd, Cu, Ni and Pb in Concholepas concholepas in a coastal environmental sacrifice zone (Chile) to assess potential human-health risks by consumption of C. concholepas. The Cu and Cd content was found to be above the safety level established in chilean and international regulations. The Estimated Daily Intake (EDI) and Target Hazard Quotient (THQ) for As were comparatively high with respect to the other metals analysed. The THQ-As and Hazard Index (HI) suggest a moderate carcinogenic risk due to the consumption of C. concholepas in six of the nine sectors analysed. THQ and HI are reasonable indicators to assess risks to human-health from the consumption of shellfish with HMs. C. concholepas can be considered as a biomonitor to study metal(loid)s on the Chilean coast.

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INTRODUCTION: Karinia brevis, a marine dinoflagellate, is the causative organism for "red-tide" on the east coast of Florida.This microbe produces brevetoxins, which bioaccumulate in filter feeding bivalve shellfish. In humans, inhalational exposure is common, while ingestion of contaminated shellfish is more rare. Ingested brevetoxin causes gastrointestinal and neurological symptoms collectively known as neurotoxic shellfish poisoning. CASE CLUSTER: A group of tourists collected clams from a beach during a red tide event. The clams were soaked in brine, microwaved, and consumed for lunch. The index patient experienced seizure-like activity postprandially prompting the cohort to present for medical attention. Five people presented to the emergency department with neurotoxic shellfish poisoning-related symptoms. All patients received supportive care only. Symptoms resolved within 24 hours. Serum brevetoxin concentrations were reported for four patients. DISCUSSION: Ingestion of brevetoxin is rare but may become more common as the frequency and severity of "red-tide" events increase. In our cluster, each person consumed a different number of clams and presented with classic and some "non-classic" symptoms. A trend toward more severe symptoms with a larger number of clams ingested was observed. CONCLUSIONS: This case cluster describes the clinical course of individuals after consumption of brevetoxin contaminated shellfish.

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The effects of the toxic dinoflagellate Alexandrium catenella were investigated on growth, survival, and histopathology in larvae and spat of the Tehuelche scallop Aequipecten tehuelchus from Patagonia, Argentina. The study consisted of laboratory incubations of scallop larvae/spat with A. catenella, using environmentally realistic abundances of the dinoflagellate. Survival, growth, and histopathological effects were documented for scallop larvae/spat before, during, and after 7-day-long exposure to A. catenella. The scallops were grouped in flasks containing 0 (control), 20, 200, and 2000 cells mL-1 of A. catenella. The presence of A. catenella induced reduced larvae survival after 24 h, whereas a clear effect was observed after 3 days (survival of control larvae 95%, 72, and 79% for 20 and 200 cells mL-1, respectively, and 43% for 2000 cells mL-1). The growth rates of the control larvae and those exposed to 20 mL-1 cells were significantly different from zero. Histopathological effects (melanization, loss of connective tissue, necrosis, and inflammatory responses) were observed in spat exposed to A. catenella. These effects were more pronounced at the highest dinoflagellate concentration. Blooms of A. catenella frequently coincide with the reproductive season of A. tehuelchus, thus there is a need to further study the relationship between harmful algal blooms and the effect on scallops' natural populations in the region.

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Introduction: Small-scale fishing is responsible for at least 40% of the fish consumed in the world. In Brazil, the worker in this sector is the artisanal fisherman, who accounts for one in every 200 Brazilians. Artisanal fishing is part of the informal economy; therefore, the pathologies that affect these fishermen are invisible in the country's official statistics. Musculoskeletal disorders represent a major socioeconomic and public health problem, but their prevalence is little known among non-formal workers. Objective: to estimate the prevalence of musculoskeletal disorders (MSDs) in the lower limbs and to verify the associated factors among artisanal fishermen/ fisherwomen from Saubara, Bahia, Brazil. Methodology: a cross-sectional study, using the Nordic Musculoskeletal Questionnaire (NMQ), the Brazilian version of the Job Content Questionnaire (JCQ) and a questionnaire about physical demands, were used to collect information in a random sample of artisanal fishermen/shellfish gatherers, in 2013. Results: the prevalence of MSDs in lower limbs in the sample was 65.5% (n=137). The prevalence of MSDs in the thigh/knee segment, leg and ankle/foot were 48.7% (n=92), 47.7% (n=95) and 38.1% (n=72), respectively. There was also a high frequency of obesity, poor education, low wages, early age at onset of labor, and excessive workload. Factors such as age, smoking, physical demands, working time, absence of breaks and having had a previous job were associated with MSDs in the lower limbs. Conclusion: the high prevalence of MSDs in lower limbs in female artisanal fishermen indicates the need to develop strategies for prevention, diagnosis and reporting of these diseases.

Introdução: a pesca em pequena escala é responsável por pelo menos 40% do pescado consumido no mundo e, no Brasil, o trabalhador desse setor é o pescador artesanal, que contabiliza um a cada 200 brasileiros. Por se tratar de uma atividade da economia informal, as patologias que afetam esses pescadores são praticamente invisíveis nas estatísticas oficiais do país. Nesse contexto, os distúrbios musculoesqueléticos representam um grande problema socioeconômico e de saúde pública, mas sua prevalência é pouco conhecida entre trabalhadores não formais. Objetivo: estimar a prevalência de distúrbios musculoesqueléticos nos membros inferiores e fatores associados, em pescadores artesanais/marisqueiras de Saubara, Bahia, Brasil. Metodologia: trata-se de um estudo transversal, utilizando o Nordic Musculoskeletal Questionnaire, a versão brasileira do Job Content Questionnaire e um questionário sobre demandas físicas, para a coleta de informações em uma amostra aleatória de pescadores artesanais/marisqueiras, ocorrida em 2013. Resultados: a prevalência de distúrbios musculoesqueléticos em membros inferiores na amostra foi de 65,5% (n=137); a prevalência no segmento coxa/joelho, perna e tornozelo/pé foi de 48,7% (n=92), 47,7% (n=95) e 38,1% (n=72), respectivamente. Observaram-se também alta frequência de obesidade, baixa escolaridade, baixos salários, idade precoce para o início do trabalho e carga horária excessiva. Fatores como idade, tabagismo, demandas físicas, tempo de trabalho, ausência de pausas e trabalho anterior, estavam associados aos referidos distúrbios. Conclusão: A alta prevalência de distúrbios musculoesqueléticos dos membros inferiores em pescadoras artesanais indica a necessidade de desenvolver estratégias de prevenção, diagnóstico e notificação dessas doenças

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Bioeroding sponges can cause extensive damage to aquaculture and wild shellfish fisheries. It has been suggested that heavy sponge infestations that reach the inner cavity of oysters may trigger shell repair and lead to adductor detachment. Consequently, energy provision into shell repair could reduce the energy available for other physiological processes and reduce the meat quality of commercially fished oysters. Nevertheless, the impacts of boring sponges on oysters and other shellfish hosts are inconclusive. We studied the interaction between boring sponges and their hosts and examined potential detrimental effects on an economically important oyster species Ostrea chilensis from Foveaux Strait (FS), New Zealand. We investigated the effect of different infestation levels with the bioeroding sponge Cliona sp. on commercial meat quality, condition, reproduction, and disease susceptibility. Meat quality was assessed with an index based on visual assessments used in the FS O. chilensis fishery. Meat condition was assessed with a common oyster condition index, while histological methods were used to assess sex, gonad stage, reproductive capacity, and pathogen presence. Commercial meat quality and condition of O. chilensis were unaffected by sponge infestation. There was no relationship between sex ratio, gonad developmental stage, or gonad index and sponge infestation. Lastly, we found no evidence that sponge infestation affects disease susceptibility in O. chilensis. Our results suggest that O. chilensis in FS is largely unaffected by infestation with Cliona sp. and therefore reinforces the growing body of evidence that the effects of sponge infestation can be highly variable among different host species, environments, and habitats.

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