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1.
Ecotoxicol Environ Saf ; 204: 111042, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32738626

RESUMO

Paralytic shellfish poisoning (PSP) toxins have received considerable attention in recent years because of their adverse effects on marine breeding industries and human health. In this study, a reliable method for the analysis of extracellular PSP toxins in the culture medium of marine toxic dinoflagellates was developed for the first time using graphitized carbon black-solid-phase extraction and hydrophilic interaction liquid chromatography-high-resolution mass spectrometry. The limit of quantification of typical PSP toxins in algal culture medium ranged from 0.072 µg/L to 0.151 µg/L under optimal conditions. Satisfactory absolute recoveries (87.5%-102.4%), precision (relative standard deviation ≤ 7.6%), and linearity (R2 ≥ 0.9998) were also achieved. In addition, the proposed method was applied to screen and determine the extracellular PSP toxins of two typical toxigenic dinoflagellates, Alexandrium minutum and Alexandrium tamarense. The total concentrations of the extracellular PSP toxins in A. minutum and A. tamarense over the whole growth period were within 2.0-735.5 and 2.0-19.2 µg/L, respectively. The concentrations of extracellular PSP toxins varied remarkably in the different growth stages of A. minutum and A. tamarense, and the contents of some extracellular PSP toxins were substantially higher than those of intracellular PSP toxins. Therefore, the extracellular PSP toxins released by toxigenic red tide algae cannot be ignored, and their environmental fate, bioavailability, and potential harm to aquatic environment need to be investigated in future studies.


Assuntos
Cromatografia Líquida/métodos , Meios de Cultura/química , Dinoflagelados/metabolismo , Toxinas Marinhas/análise , Espectrometria de Massas/métodos , Extração em Fase Sólida/métodos , Interações Hidrofóbicas e Hidrofílicas , Intoxicação por Frutos do Mar , Fuligem/química
2.
Toxicon ; 186: 19-25, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32738246

RESUMO

The first survey of the phycotoxin profile in mussels (Mytilus galloprovincialis) from the coastal waters of Bosnia and Herzegovina (The Bay of Neum, Middle Adriatic Sea) in correlation to the Makarska City Bay (Croatia, Middle Adriatic Sea) was conducted in 2017. Throughout the monitoring period, occasions of gymnodimine (GYM) and azaspiracid (AZA2) shellfish toxicity were recorded in concentrations that do not endanger human health. The occurrence of yessotoxins (YTXs), the most common toxins found in the Adriatic Sea, was correlated to the presence of the Gonyaulax species, a potential source of YTX. The DSP group of toxins is represented by the ester-OA. Phytoplankton analysis confirmed the presence of dinoflagellates from the Prorocentrum genus, a species associated with DSP toxicity. Occurrence frequency and variability of toxin composition were investigated in conjunction to physico-chemical parameters in the surrounding sea water. In the central Adriatic Sea, the infestation period ranges in general from June to August. However, the depuration phase extended beyond September in the Bay of Neum, increasing the length of the decontamination period.


Assuntos
Toxinas Marinhas/análise , Venenos de Moluscos/análise , Frutos do Mar/estatística & dados numéricos , Animais , Croácia , Dinoflagelados , Compostos Heterocíclicos com 3 Anéis/análise , Humanos , Hidrocarbonetos Cíclicos/análise , Iminas/análise , Mytilus , Oxocinas/análise , Fitoplâncton , Alimentos Marinhos , Intoxicação por Frutos do Mar , Compostos de Espiro/análise
3.
Toxicon ; 184: 215-228, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32593754

RESUMO

An assessment of the major pigments and neurotoxins and a description of the phytoplankton community were carried out within the coastal region of Rio de Janeiro State (Brazil), during winter and the following spring of 2018. Overall, six stations were investigated for oceanographic conditions (with CTD casts). Filtered water samples were used to estimate the chlorophyll a (CHL-a), carotenoids (CAR), and phycobiliproteins (PHY) using UV-Vis spectrophotometry, as well as the quantification of saxitoxins (STX) and domoic acid (DA), through High Performance Liquid Chromatography (HPLC). Planktonic organisms were counted using sedimentation chambers of different volumes and an inverted microscope. A cluster analysis, SIMPER, and ANOSIM were applied to the phytoplankton data along with diversity indexes, and non-parametric statistics to phycotoxins and pigments. There was a significant difference between the winter and spring phytoplankton community, associated with the mixed layer depth (r2 = -0.626, p < 0.05) and temperature (r2 = 0.641, p < 0.05). Phytoplankton biomass and C:CHL-a indicated a higher production during the winter than in spring, with the potentially toxic genus Pseudo-nitzschia responsible for 12.79% of autotrophic abundance (SIMPER output). Pigments showed a slight increase in CAR during spring, while PHY remained at trace concentrations. Both the DA and STX were quantified in winter and spring, but with significant differences only for STX between the sampling periods. Among the 71 taxa, 11 were identified as potentially toxic with an emphasis on STX-producing dinoflagellates and cyanobacteria, such as Alexandrium sp., Gymnodinium spp. along with Trichodesmium spp. Season-related environmental variability may be the major driving force modulating the mixed assemblage of species that support different levels of phycotoxins.


Assuntos
Monitoramento Ambiental , Toxinas Marinhas/toxicidade , Fitoplâncton , Biomassa , Brasil , Clorofila A , Cianobactérias , Diatomáceas , Dinoflagelados , Ácido Caínico/análogos & derivados , Toxinas Marinhas/análise , Neurotoxinas , Estações do Ano , Água do Mar , Trichodesmium
4.
PLoS One ; 15(6): e0235015, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32559229

RESUMO

Representatives of the marine dinophyte family Amphidomataceae produce lipophilic phycotoxins called azaspiracids (AZA) which may cause azaspiracid shellfish poisoning (AZP) in humans after consumption of contaminated seafood. Three of the four known toxigenic species are observed frequently in the eastern North Atlantic. In 2018, a research survey was performed to strengthen knowledge on the distribution and abundance of toxigenic Amphidomataceae and their respective toxins in Irish coastal waters and in the North Sea. Species-specific quantification of the three toxigenic species (Azadinium spinosum, Azadinium poporum and Amphidoma languida) was based on recently developed qPCR assays, whose performance was successfully validated and tested with specificity tests and spike experiments. The multi-method approach of on-board live microscopy, qPCR assays and chemical AZA-analysis revealed the presence of Amphidomataceae in the North Atlantic including the three targeted toxigenic species and their respective AZA analogues (AZA-1, -2, -33, -38, -39). Azadinium spinosum was detected at the majority of Irish stations with a peak density of 8.3 x 104 cells L-1 and AZA (AZA-1, -2, -33) abundances up to 1,274 pg L-1. Amphidoma languida was also present at most Irish stations but appeared in highest abundance in a bloom at a central North Sea station with a density of 1.2 x 105 cells L-1 and an AZA (AZA-38, -39) abundances of 618 pg L-1. Azadinium poporum was detected sporadically at the Irish south coast and North Sea and was rather low in abundance during this study. The results confirmed the wide distribution and frequent occurrence of the target species in the North Atlantic area and revealed, for the first time, bloom abundances of toxigenic Amphidomataceae in this area. This emphasizes the importance of future studies and monitoring of amphidomatacean species and their respective AZA analogues in the North Atlantic.


Assuntos
Biomassa , Dinoflagelados/fisiologia , Toxinas Marinhas/análise , Compostos de Espiro/análise , Dinoflagelados/metabolismo , Toxinas Marinhas/metabolismo , Mar do Norte , Água do Mar/química , Compostos de Espiro/metabolismo
5.
Chemosphere ; 256: 127019, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32417588

RESUMO

Marine and freshwater toxins contaminate water resources, shellfish and aquaculture products, causing a broad range of toxic effects in humans and animals. Different core-shell nanoparticles were tested as a new sorbent for removing marine and freshwater toxins from liquid media. Water solutions were contaminated with 20 µg/L of marine toxins and up to 50 µg/L of freshwater toxins and subsequently treated with 250 or 125 mg/L of nanoparticles. Under these conditions, carbon nanoparticles removed around 70% of saxitoxins, spirolides, and azaspiracids, and up to 38% of diarrheic shellfish poisoning toxins. In the case of freshwater toxins, the 85% of microcystin LR was eliminated; other cyclic peptide toxins were also removed in a high percentage. Marine toxins were adsorbed in the first 5 min of contact, while for freshwater toxins it was necessary 60 min to reach the maximum adsorption. Toxins were recovered by extraction from nanoparticles with different solvents. Gymnodinium catenatum, Prorocentrum lima, and Microcystis aeruginosa cultures were employed to test the ability of nanoparticles to adsorb toxins in a real environment, and the same efficacy to remove toxins was observed in these conditions. These results suggest the possibility of using the nanotechnology in the treatment of contaminated water or in chemical analysis applications.


Assuntos
Toxinas Marinhas/química , Nanoestruturas/química , Compostos de Espiro/química , Purificação da Água/métodos , Animais , Dinoflagelados , Água Doce/química , Humanos , Fenômenos Magnéticos , Toxinas Marinhas/análise , Microcistinas , Microcystis , Saxitoxina , Alimentos Marinhos/análise , Frutos do Mar/análise , Intoxicação por Frutos do Mar , Compostos de Espiro/análise
6.
Toxicon ; 180: 1-10, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32246951

RESUMO

Pinnatoxins (PnTXs) are a group of emerging marine biotoxins produced by the benthic dinoflagellate Vulcanodinium rugosum, currently not regulated in Europe or in any other country in the world. In France, PnTXs were detected for the first time in 2011, in mussels from the Ingril lagoon (South of France, Mediterranean coast). Since then, analyses carried out in mussels from this lagoon have shown high concentrations of PnTXs for several months each year. PnTXs have also been detected, to a lesser extent, in mussels from other Mediterranean lagoons and on the Atlantic and Corsican coasts. In the French data, the main analog is PnTX G (low levels of PnTX A are also present in some samples). No cases of PnTXs poisoning in humans have been reported so far in France or anywhere else in the world. In mice, PnTXs induce acute neurotoxic effects, within a few minutes after oral administration. Clinical signs of toxicity include decreased mobility, paralysis of the hind legs, tremors, jumps and breathing difficulties leading to death by respiratory arrest at high doses. The French agency for food safety (ANSES) recently conducted a review of the state of knowledge related to PnTXs and V. rugosum. Based on (i) the clinical signs of toxicity in mice, (ii) the mode of action of PnTXs as nicotinic acetylcholine receptor competitive antagonists and (iii) knowledge on drugs and natural toxins with PnTX-related pharmacology, potential human symptoms have been extrapolated and proposed. In this work, a provisional acute benchmark value for PnTX G of 0.13 µg/kg bw per day has been derived from an oral acute toxicity study in mice. Based on this value and a large shellfish meat portion size of 400g, a concentration lower than 23 µg PnTX G/kg shellfish meat is not expected to result in adverse effects in humans. ANSES recommends taking into account PnTXs in the French official monitoring program for shellfish production and identified data gaps to refine health risk assessment.


Assuntos
Exposição Dietética/estatística & dados numéricos , Monitoramento Ambiental , Inocuidade dos Alimentos , Toxinas Marinhas/análise , Frutos do Mar/estatística & dados numéricos , Animais , Bivalves , Dinoflagelados , França , Humanos , Toxinas Marinhas/metabolismo , Camundongos , Medição de Risco , Alimentos Marinhos/estatística & dados numéricos , Intoxicação por Frutos do Mar
7.
Toxicon ; 180: 79-88, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32289356

RESUMO

Physiological plasticity gives HABs species the ability to respond to variations in the surrounding environment. The aim of this study was to examine morphological and physiological variability in Alexandrium pacificum R.W. Litaker (Group IV) (former Alexandrium catenella) blooming in Annaba bay, Algeria. Monoclonal cultures of up to 30 strains of this neurotoxic dinoflagellate were established by the germination of single resting cysts from the surface sediment of this southern Mediterranean marine ecosystem. Ribotyping confirmed formally for the first time that A. pacificum is developing in Eastern Algerian waters. Toxin analyses of A. pacificum strains revealed substantial intraspecific variability in both the profile and toxin amount. However, the toxin profile of most strains is characterized by the dominance of GTX6 (up to 96 mol %) which is the less toxic paralytic molecule. The toxin concentrations in the isolated strains varied widely between 3.8 and 30.82 fmol cell-1. We observed an important variation in the growth rate of the studied A. pacificum strains with values ranging from 0.05 to 0.33 d-1. The lag time of the studied strains varied widely and ranged from 4 to 20 days. The intraspecific diversity could be a response to the selection pressure which may be exerted by different environmental conditions over time and which can be genetically and in turn physiologically expressed. This study highlights, for the first time, that the sediment of a limited area holds an important diversity of A. pacificum cysts which give when germinate populations with noticeable physiological plasticity. Consequently, this diversified natural populations allow an exceptional adaptation to specific environmental conditions to outcompete local microalgae and to establish HABs which could explain why this dinoflagellate is successful and expanding worldwide.


Assuntos
Dinoflagelados/fisiologia , Toxinas Marinhas/análise , Argélia , Baías , Ecossistema , Toxinas Marinhas/metabolismo , Intoxicação por Frutos do Mar , Toxinas Biológicas , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo
8.
Ecotoxicol Environ Saf ; 197: 110647, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32315787

RESUMO

Some toxigenic dinoflagellates can produce lipophilic marine algal toxins (LMATs), which are potent threats to marine breeding industries. In this study, a new method based on the profiling analysis of six LMAT classes in phytoplankton was developed for the monitoring and warning of LMATs in mariculture zones. This method was applied to monitor and evaluate LMATs in the Jiaozhou Bay and the Changjiang estuary in China. Results demonstrated that the occurrence and spatiotemporal variations of LMATs in mariculture zones can be revealed by the toxin profiles of phytoplankton, indicating the method's effectiveness for the comprehensive monitoring of the composition and levels of various LMATs in coastal aquaculture zones. The method was further used as an alarm for potential pollution risk from LMATs in mariculture zones at an early stage. The "alert" thresholds of LMAT pollution in the mariculture zones were preliminarily proposed based on the statistical data analysis of LMATs in phytoplankton in three typical mariculture areas in China. This study is the first to conduct simultaneous monitoring and warning of multi-class LMATs based on toxin profiles of phytoplankton, thereby providing new insight into the monitoring and early warning of natural poisonous pollutants in coastal aquaculture zones around the world.


Assuntos
Aquicultura , Dinoflagelados/química , Monitoramento Ambiental/métodos , Toxinas Marinhas/análise , Fitoplâncton/química , Poluentes Químicos da Água/análise , China , Água do Mar/química
9.
PLoS Negl Trop Dis ; 14(3): e0008060, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32163415

RESUMO

The northeast (NE) region of Brazil commonly goes through drought periods, which favor cyanobacterial blooms, capable of producing neurotoxins with implications for human and animal health. The most severe dry spell in the history of Brazil occurred between 2012 and 2016. Coincidently, the highest incidence of microcephaly associated with the Zika virus (ZIKV) outbreak took place in the NE region of Brazil during the same years. In this work, we tested the hypothesis that saxitoxin (STX), a neurotoxin produced in South America by the freshwater cyanobacteria Raphidiopsis raciborskii, could have contributed to the most severe Congenital Zika Syndrome (CZS) profile described worldwide. Quality surveillance showed higher cyanobacteria amounts and STX occurrence in human drinking water supplies of NE compared to other regions of Brazil. Experimentally, we described that STX doubled the quantity of ZIKV-induced neural cell death in progenitor areas of human brain organoids, while the chronic ingestion of water contaminated with STX before and during gestation caused brain abnormalities in offspring of ZIKV-infected immunocompetent C57BL/6J mice. Our data indicate that saxitoxin-producing cyanobacteria is overspread in water reservoirs of the NE and might have acted as a co-insult to ZIKV infection in Brazil. These results raise a public health concern regarding the consequences of arbovirus outbreaks happening in areas with droughts and/or frequent freshwater cyanobacterial blooms.


Assuntos
Morte Celular/efeitos dos fármacos , Microcefalia/patologia , Envenenamento/complicações , Envenenamento/patologia , Saxitoxina/toxicidade , Infecção por Zika virus/complicações , Infecção por Zika virus/patologia , Animais , Toxinas Bacterianas/análise , Toxinas Bacterianas/toxicidade , Encéfalo/patologia , Brasil/epidemiologia , Células Cultivadas , Modelos Animais de Doenças , Surtos de Doenças , Feminino , Humanos , Incidência , Toxinas Marinhas/análise , Toxinas Marinhas/toxicidade , Camundongos Endogâmicos C57BL , Microcistinas/análise , Microcistinas/toxicidade , Modelos Teóricos , Neurotoxinas/análise , Neurotoxinas/toxicidade , Saxitoxina/análise , Água/química
10.
Chemosphere ; 246: 125622, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31918075

RESUMO

Molecularly imprinted polymers (MIPs) are attracting substantial interest as artificial plastic antibodies because of their biometric capability for targeting small molecules. In this study, molecularly imprinted silica material-coated quantum dots (MIS-QDs) with selective recognition capability to okadaic acid (OA) were developed and characterized. The synthesized MIS-QDs with specific imprinting cavities exhibited excellent recognition capability similar to those of biological antibodies and high fluorescence (FL) quenching selectivity for OA. Furthermore, the MIS-QDs with unsaturated bonds were immobilized onto the surface of 96-well microplates by cold plasma-induced grafting. A novel direct competitive microplate assay strategy was then proposed. The FL quenching properties of the developed microplate assay showed an excellent linear relationship with OA in the range of 10.0-100.0 µg/kg with a correlation coefficient of 0.9961. The limit of detection for OA was 0.25 µg/kg in the shellfish samples. The mean quantitative recoveries were 92.5%-101.0% and 92.9%-101.3%, with relative standard deviations of <7.7% and 7.6% for pure solvents and purified shellfish samples, respectively. The established microplate assay strategy can be used as a rapid and high-throughput method for analyzing OA marine toxins in biological samples.


Assuntos
Análise em Microsséries/métodos , Impressão Molecular/métodos , Ácido Okadáico/isolamento & purificação , Pontos Quânticos/química , Animais , Fluorescência , Toxinas Marinhas/análise , Ácido Okadáico/análise , Frutos do Mar , Dióxido de Silício/química
11.
Chemosphere ; 243: 125404, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31995871

RESUMO

Scombroid poisoning in fish-based and other food products has raised concerns due to toxicity outbreaks and incidences associated with histamine, thus measuring the amount of histamine toxic molecule is considered crucial quality indicator of food safety and human health. In this study, liposome-based measurement of histamine was performed via rupturing mechanism of sulforhodamine B dye encapsulated anti-histamine antibody conjugated liposomal nanovesicles. The immunosensing ability of immuno-liposomal format was assessed by monitoring the fluorescence at excitation/emission wavelength of 550/585 nm. Immuno-liposomal format assays were considered, one based on single wash procedure (Method 1), which had a detection limit of 10 ppb and quantification limit 15-80 ppb. While Method 2 based on one-by-one wash procedure had a detection limit of 2-3 ppb and quantification limit 8.5 ppb-200 ppm that required 2 h 30 min to perform. In view of better quantification limit, Method 2 was chosen for further tests required to validate its applicability in real samples. The feasibility of Method 2 was reconfirmed in fresh mackerel fish, and canned fish (tuna and salmon) with a similar detection limits but with low amplified fluorescence signals and sufficient levels of histamine recovery from fresh mackerel (73.50-99.98%), canned tuna (79.08-103.74%) and salmon (74.56-99.02%). The specificity and method accuracy were expressed as % CV in the range 5.34%-8.48%. Overall, the developed multi-well sensing system (Method 2) showed satisfactory specificity, cost effectiveness, rapidity, and stability for monitoring histamine toxicity as a practical food diagnostic device.


Assuntos
Imunofluorescência/métodos , Contaminação de Alimentos/análise , Histamina/análise , Toxinas Marinhas/análise , Toxinas Marinhas/envenenamento , Animais , Produtos Pesqueiros/análise , Peixes , Inocuidade dos Alimentos , Histamina/imunologia , Antagonistas dos Receptores Histamínicos , Humanos , Limite de Detecção , Lipossomos/imunologia , Rodaminas , Salmão , Alimentos Marinhos/análise , Sensibilidade e Especificidade , Atum
12.
Chemosphere ; 243: 125352, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31759209

RESUMO

Lipophilic phycotoxins (LPs) pose significant threats to the health of marine mammals, birds, and human beings. The distribution and components of lipophilic phycotoxins contamination in subtropical area in the South China Sea are rarely known. This study systematically assessed the composition, concentration, and distribution of typical LPs in a typical subtropical bay, Daya Bay located in the South China Sea. Phytoplankton, seawater, suspended particulate matter, sediments, and shellfish samples were simultaneously collected from Daya Bay, and analyzed using liquid chromatography with tandem mass spectrometry. Okadaic acid, dinophysistoxins-1, pectenotoxins-2, yessotoxin and its derivate homo-yessotoxin, azaspiracid-2, 13-desmethyl spirolide C and gymnodimine were widely spread in multiple media in Daya Bay. Pectenotoxins-2 was the most widely distributed and highly concentrated toxin in the marine environments of Daya Bay. Toxin homo-yessotoxin was only detected in sediments and shellfish samples, and none of yessotoxin group components were found in phytoplankton and seawater, indicating that sediments were the major source of yessotoxin in shellfish. The study strongly demonstrated the lipophilic phycotoxins accumulated in shellfish are multisource, not only derived from toxigenic algae, but also from other marine media containing lipophilic phycotoxins. This study systematically distinguished multi-pathways of bioaccumulation of LPs in the marine shellfish.


Assuntos
Monitoramento Ambiental , Toxinas Marinhas/análise , Animais , Baías/química , China , Cromatografia Líquida/métodos , Furanos , Compostos Heterocíclicos com 3 Anéis , Humanos , Hidrocarbonetos Cíclicos , Iminas , Ácido Okadáico/análise , Oxocinas , Fitoplâncton/química , Piranos , Alimentos Marinhos/análise , Água do Mar , Frutos do Mar/análise , Compostos de Espiro , Espectrometria de Massas em Tandem
13.
Aquat Toxicol ; 218: 105371, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31790939

RESUMO

Harmful algal bloom (HAB) toxins have severe negative impacts on marine mammals, particularly for Florida bottlenose dolphins (Tursiops truncatus) which frequently experience mass mortality events. Dolphins on the Florida Atlantic coast inhabit a region endemic to two HAB species, Karenia brevis and Pyrodinium bahamense, which produce the neurotoxins brevetoxin (PbTx) and saxitoxin (STX), respectively. Although toxic HABs and associated dolphin mortality events have been reported from this region, there is a lack of available data necessary for comparing toxin exposure levels between bloom ('exposed') conditions and non-bloom ('baseline') conditions. Here we present a 10-year dataset of PbTx and STX concentrations detected in dolphins stranding in this region, and compare the toxin loads from HAB-exposed dolphins to those detected in dolphins recovered in the absence of a HAB. We analyzed liver tissue samples from dead-stranded dolphins (n = 119) recovered and necropsied between 2002-2011, using an enzyme-linked immunosorbent assay (ELISA) modified for use with mammalian tissues. For dolphins recovered during baseline conditions, toxin-positive samples ranged in concentration from 0.27 to 1.2 ng/g for PbTx and from 0.41 to 1.9 ng/g for STX. For K. brevis-exposed dolphins, concentrations of up to 12.1 ng PbTx/g were detected, and for P. bahamense-exposed dolphins, concentrations of up to 9.9 ng STX/g were detected. Baseline PbTx values were similar to those reported in other regions where K. brevis blooms are more frequent and severe, but HAB-exposed PbTx values were considerably lower relative to these other regions. Since no baseline STX dolphin data exist for any region, our data serve as a first step towards establishing reference STX values for potential dolphin mortality events associated with STX-producing blooms in the future. This study demonstrates that although HABs in eastern Florida are only infrequently associated with dolphin mortalities, the presence of toxins in these animals may pose significant health risks in this region.


Assuntos
Golfinho Nariz-de-Garrafa/metabolismo , Monitoramento Ambiental/métodos , Proliferação Nociva de Algas , Toxinas Marinhas/análise , Oxocinas/análise , Saxitoxina/análise , Poluentes Químicos da Água/análise , Animais , Dinoflagelados/crescimento & desenvolvimento , Ensaio de Imunoadsorção Enzimática , Florida , Fígado/química , Fígado/metabolismo , Toxinas Marinhas/toxicidade , Oxocinas/toxicidade , Rios/química , Saxitoxina/toxicidade , Poluentes Químicos da Água/toxicidade
14.
Mar Drugs ; 17(11)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683576

RESUMO

Marine sediments can reserve many environmental pollutants. Lipophilic marine phycotoxins (LMPs) are natural toxic substances widespread in the marine environment; however, evidence of their existence in sediment is scarce. In the present study, in order to explore the occurrence and distribution characteristics of LMPs in sediment, surface sediment samples collected from a tropical area of Daya Bay (DYB) at different seasons, were analyzed using liquid chromatography with tandem mass spectrometry (LC-MS/MS). According to the results, up to six toxin compounds were detected in sediment samples from DYB, OA and DTX1 had the highest levels, followed by PTX2, homo-YTX, AZA2, and GYM. Although AZA2 and GYM were found in most of the sediment, OA, DTX1, homo-YTX, and PTX2 were the predominant toxin compounds, and PTX2 was the most ubiquitous toxin in sediment. The spatial distribution of LMP components in the sediment fluctuated with sampling times, partially according to the physical-chemical parameters of the sediment. There are likely several sources for LMPs existing in surface sediments, but it is difficult to determine contributions of a specific toxin-source in the sediment. Therefore, marine sediments may be a toxin reservoir for LMPs accumulation in benthic organisms via food chains.


Assuntos
Monitoramento Ambiental/métodos , Toxinas Marinhas/análise , Poluentes Químicos da Água/análise , Baías , China , Poluentes Ambientais/análise
15.
Toxicon ; 171: 62-65, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31614156

RESUMO

Algal toxins (domoic acid, saxitoxin, okadaic acid) were monitored at seven locations off southern California using Solid Phase Adsorption Toxin Tracking. At least two types of toxins were found at all locations, with co-occurrence of two and three toxins in 12% and 10% of samples, respectively. This study expands our limited understanding of the simultaneous presence of multiple algal toxins along the coast and raises questions regarding the potential health ramifications of such co-occurrences.


Assuntos
Ácido Caínico/análogos & derivados , Ácido Okadáico/análise , Saxitoxina/análise , Adsorção , California , Monitoramento Ambiental , Proliferação Nociva de Algas , Ácido Caínico/análise , Toxinas Marinhas/análise , Água do Mar/química
16.
Mar Pollut Bull ; 145: 105-117, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31590766

RESUMO

The Beagle Channel is a remote subantarctic environment where mussel aquaculture initiatives have existed since the early 1990s. Here we analyze phytoplankton biomass and composition, and the occurrence of harmful microalgae species and their toxins at three sites during the period 2015-2016. The occurrence of potentially harmful algae was observed throughout the study period, including toxigenic dinoflagellates such as Alexandrium catenella (Group I of the A. tamarense complex), A. ostenfeldii, Dinophysis acuminata, Gonyaulax spinifera, Azadinium sp., and the diatoms Pseudo-nitzschia australis and P. fraudulenta. Toxic dinoflagellates were detected in low densities whereas a Pseudo-nitzschia bloom was observed in late February. Isolates of A. catenella and P. delicatissima sensu stricto were phylogenetically characterized. The toxin profile of A. catenella was dominated by GTX4, while P. delicatissima sensu stricto showed no production of the neurotoxin domoic acid in culture conditions. The results provide base-line information for the management of harmful algal blooms in this little explored subantarctic area.


Assuntos
Aquicultura , Diatomáceas/química , Dinoflagelados/química , Toxinas Marinhas/análise , Fitoplâncton/química , Animais , Biomassa , Diatomáceas/classificação , Diatomáceas/crescimento & desenvolvimento , Dinoflagelados/classificação , Dinoflagelados/crescimento & desenvolvimento , Proliferação Nociva de Algas , Microalgas/química , Microalgas/classificação , Microalgas/crescimento & desenvolvimento , Fitoplâncton/classificação , Fitoplâncton/crescimento & desenvolvimento , América do Sul
17.
Environ Pollut ; 255(Pt 2): 113299, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31585405

RESUMO

Lipophilic marine algal toxins (LMATs) pose a potential threat to the health of marine shellfish consumers and marine breeding industries. In this study, LMATs in dissolved phases (DP) and particulate phases (PP) in the seawater of Jiaozhou Bay were accurately determined over four seasons to understand their composition, level, phase partitioning, spatiotemporal variation, and potential sources in aquatic environments of a typical semi-closed mariculture bay. Various LMATs, such as okadaic acid (OA), dinophysistoxin-1 (DTX1), dinophysistoxin-2 (DTX2), gymnodimine (GYM), 13-desmethyl spirolide C (SPX1), pectenotoxin-2 (PTX2), pectenotoxin-2 seco acid (PTX2 SA), and pectenotoxin-11 (PTX11), were detected in DP and PP; of these, OA and PTX2 were the dominant LMATs in DP and PP, respectively. The average proportion of ΣLMATs in DP (97.5%) was significantly higher than that in PP (2.5%), which indicates that LMATs are predominantly partitioned into DP. The total concentrations of LMATs in DP ranged from 4.16 ng/L to 23.19 ng/L (mean, 13.35 ng/L) over four seasons. The highest levels of LMATs in DP and PP were found in summer (mean, 16.71 ng/L) and spring, respectively, while the maximum variety of LMATs was found in autumn. This result suggests that seasonal changes could influence the composition, concentration, and phase partitioning of LMATs in aquatic environments of a coastal semi-closed mariculture bay. ΣLMAT concentrations were higher in the western region than in the eastern region of the bay, where shellfish may have a greater risk of exposure. Dinophysis acuminata, Dinophysis fortii, and Prorocentrum minimum were the potential sources of LMATs in the aquaculture seawater. Overall, various LMATs occurred in the semi-closed mariculture bay, and the persistence and bioavailability of these toxins in aquaculture seawater should be determined in future research.


Assuntos
Baías/química , Dinoflagelados/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Toxinas Marinhas/análise , Água do Mar/química , Animais , Aquicultura , China , Crustáceos/química , Estações do Ano , Frutos do Mar/análise
18.
J Chromatogr A ; 1608: 460404, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31378529

RESUMO

An easy-prepared adsorbent with high stable and good dispersibility is especially valuable for the development of magnetic solid-phase extraction (MSPE) techniques. In this study, magnetic nitrogen-doped carbon nanotube cages (N-CNTCs) were synthesized via direct carbonization of cobalt (II)-containing metal-organic frameworks. During carbonization, cobalt ions inside the MOFs were converted into magnetic functional nanoparticles of N-CNTCs. Simultaneously, large amounts of nitrogen, originating from the organic ligands, were doped into the carbon framework. This unique structure gave the N-CNTCs excellent chemical stability, high affinity, and good dispersibility. The synthesized magnetic N-CNTCs were then used for MSPE of okadaic acid (OA) from aquatic samples. A simple, efficient, and sensitive method for detecting and quantitating OA was developed by combining the above sample pretreatment technique with high-performance liquid chromatography -tandem mass spectrometry (HPLC-MS/MS). The resulting method boasts a linear dynamic range of 3.0-1000.0 pg mL-1 with good linearity (R2 ≥ 0.9994). The limit of detection (LOD) and limit of quantification (LOQ) were 1.3 pg mL-1 and 3.0 pg mL-1, respectively. Several shellfish and seafood samples were analyzed using the developed method, showing satisfactory recoveries (82.0-107.0%) and relative standard deviations (<4.5%). The developed method was also used to investigate the OA distribution in crab tissues. Our results demonstrate that magnetic N-CNTCs are promising adsorbents for providing reliable support for the early warning and tracing to the source of algae toxins.


Assuntos
Técnicas de Química Analítica/métodos , Cobalto/química , Nanotubos de Carbono/química , Nitrogênio/química , Ácido Okadáico/isolamento & purificação , Extração em Fase Sólida/métodos , Técnicas de Química Analítica/normas , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Magnetismo , Toxinas Marinhas/análise , Toxinas Marinhas/isolamento & purificação , Ácido Okadáico/análise , Frutos do Mar/análise , Espectrometria de Massas em Tandem
19.
Ecotoxicol Environ Saf ; 183: 109477, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31369939

RESUMO

The increasing eutrophication of freshwater and brackish habitats globally has led to a corresponding increase in the occurrence of harmful cyanobacterial blooms. Cyanobacteria can produce highly toxic substances such as microcystins (MCs) that affect the health of livestock, wildlife, and humans. The present study broaden the understanding of cyanobacteria ecology and MC dynamics in the field, focusing on the estimation of the production and sedimentation rates of MCs in a natural habitat. The nutrient concentrations of the reservoir water and sediment pore water were monitored at 3-h intervals for 24 h during the summer cyanobacterial bloom. The DIN uptake rate of Microcystis in the Isahaya reservoir was estimated and the large-scale blooms in the reservoir were largely controlled by the interactions between rainfall and nutrient levels in the warm season. By using calculations based on the nitrogen budgets and tracking changes of the MC concentrations in the water column, the total MC production and sedimentation rates were estimated to be 52.2 kg MCs d-1 and 21.5 kg MCs d-1, respectively. Although MCs could be degraded in the environment, the MC sedimentation still comprised 41% of the in-water production.


Assuntos
Toxinas Bacterianas/análise , Baías/microbiologia , Toxinas Marinhas/análise , Microcistinas/análise , Toxinas Bacterianas/metabolismo , Baías/química , Ecossistema , Eutrofização , Sedimentos Geológicos/química , Japão , Toxinas Marinhas/metabolismo , Microcistinas/metabolismo , Microcystis/metabolismo , Nitrogênio/metabolismo , Nutrientes , Estações do Ano
20.
J Chromatogr A ; 1608: 460409, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31399210

RESUMO

In this study two different analytical approaches have been developed to determine the presence of several cyanotoxins in saline water samples from a continental salt marsh. A salting-out assisted liquid-liquid extraction (SALLE) has been used in combination with ultra-high performance liquid chromatography-tandem mass spectrometry and UV-diode array detection (UHPLC-MS/MS and UHPLC-DAD). The target analytes are eight microcystins named MC-RR, MC-YR, MC-LR, MC-WR, MC-LA, MC-LY, MC-LW, MC-LF and nodularin (NOD), covering a wide range of polarities. The separation was achieved using a Zorbax Eclipse Plus RRHD C18 column (50 × 2.1 mm, 1.8 µm) in less than 7.5 and 5.5 min for UV and MS/MS detection, respectively. The mobile phase used consisted of water (solvent A) and acetonitrile (MeCN) (solvent B), both containing 0.01% of formic acid for DAD and 0.4% of formic acid for MS/MS detection, at a flow rate of 0.4 mL min-1. The temperature of the column was set at 25 °C and 20 µL of sample were injected. The main parameters affecting the SALLE procedure were studied and the following optimum values were obtained: neutral pH, 2 mL of acetonitrile as extraction solvent and 1.2 g of ammonium sulfate as salting-out agent for 4 mL of water sample. The validation protocols for both methods were accomplished with real water samples obtaining LODs ranging from 1.0 to 3.4 µg L-1 and 0.02 to 0.11 µg L-1 for DAD and MS/MS respectively. Although the SALLE-UHPLC-DAD methodology is easier and cheaper than UHPLC-MS/MS significantly better detection limits were achieved with tandem mass spectrometry as well as allowing for unambiguous identification. Extraction recoveries were higher than 77.0% (except for MC-RR and NOD which were 53.2% and 54.3, respectively) with satisfactory inter-day and intra-day precisions (RSD below 13.3%).


Assuntos
Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental/métodos , Extração Líquido-Líquido , Toxinas Marinhas , Microalgas/química , Água do Mar/química , Espectrometria de Massas em Tandem , Limite de Detecção , Toxinas Marinhas/análise , Toxinas Marinhas/isolamento & purificação , Microcistinas/análise , Microcistinas/isolamento & purificação , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação
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