Microalgae form the basis of marine food webs, essential in sustaining top predators including seabirds. However, certain species of microalgae synthesize biotoxins, which can accumulate in shellfish and fish and may cause harm to marine animals feeding on them. Toxins produced by dinoflagellates have been previously observed to be poisonous to seabirds.
View Article and Find Full Text PDFParetic and paralyzing syndromes affecting wild birds are widely described in the literature, with outbreaks showing an increase in frequency and intensity worldwide during recent years. In the Iberian Peninsula, a paretic clinical picture without known etiology affecting mostly gulls has been reported during the last few decades. This paretic syndrome (PS) affects waterbirds and is characterized by a set of signs of ascendent flaccid paralysis, dyspnea, and diarrhea at different levels of severity.
View Article and Find Full Text PDFThree people in England consumed fish steaks labeled as Red Snapper () originating from the Indian Ocean. Within 12 h, all three experienced sickness including nausea, vomiting, diarrhea, as well as myalgia and paresthesia. Three steaks from a single package of fish obtained from a grocery store were consumed, leaving one uneaten, which was submitted for analysis.
View Article and Find Full Text PDFHarmful algal biotoxins in the marine environment are a threat to human food safety due to their bioaccumulation in bivalve shellfish. Whilst official control monitoring provides ongoing risk management for regulated toxins in live bivalve molluscs, no routine monitoring system is currently in operation in the UK for other non-regulated toxins. To assess the potential presence of such compounds, a systematic screen of bivalve shellfish was conducted throughout Great Britain.
View Article and Find Full Text PDFTetrodotoxin (TTX) is a potent marine neurotoxin found in several phylogenetically diverse organisms, some of which are sought as seafood. Since 2015, TTX has been reported in bivalve shellfish from several estuarine locations along the Mediterranean and European Atlantic coasts, posing an emerging food safety concern. Although reports on spatial and temporal distribution have increased in recent years, processes leading to TTX accumulation in European bivalves are yet to be described.
View Article and Find Full Text PDFPharmaceuticals are recognised as environmental contaminants of emerging concern (CECs) due to their increasing presence in the aquatic environment, along with high bioactivity linked to their therapeutic use. Therefore, information on environmental levels is urgently required. This study examined the presence of a range of common pharmaceuticals in oysters and mussels intended for human consumption from England and Wales using stable isotope dilution tandem mass spectrometry.
View Article and Find Full Text PDFThe sudden mortality of African elephants (Loxodonta africana) in Botswana and Zimbabwe in 2020 provoked considerable public interest and speculation. Poaching and malicious poisoning were excluded early on in the investigation. Other potential causes included environmental intoxication, infectious diseases, and increased habitat stress due to ongoing drought.
View Article and Find Full Text PDFThe farming of shellfish plays an important role in providing sustainable economic growth in coastal, rural communities in Scotland and acts as an anchor industry, supporting a range of ancillary jobs in the processing, distribution and exporting industries. The Scottish Government is encouraging shellfish farmers to double their economic contribution by 2030. These farmers face numerous challenges to reach this goal, among which is the problem caused by toxin-producing microplankton that can contaminate their shellfish, leading to harvesting site closure and the recall of product.
View Article and Find Full Text PDFCertain species of marine microalgae produce potent biotoxins that pose a risk to human health if contaminated seafood is consumed, particularly filter feeding bivalve shellfish. In regions where this is likely to occur water and seafood produce are regularly monitored for the presence of harmful algal cells and their associated toxins, but the current approach is flawed by a lengthy delay before results are available to local authorities. Quantitative Polymerase Chain Reaction (qPCR) can be used to measure phytoplankton DNA sequences in a shorter timeframe, however it is not currently used in official testing practices.
View Article and Find Full Text PDFWarming could facilitate the intensification of toxic algal blooms, two important stressors for marine organisms that are predicted to co-occur more frequently in the future. We investigated the immediate and delayed effects of a heatwave and a simulated bloom (3 × 10 cells L of the diarrhetic shellfish toxin (DST)-producing benthic dinoflagellate Prorocentrum lima on the survival, physiology (oxygen consumption rate, condition index, immune parameters), and toxin accumulation in the Pacific rock oyster Magallana (Crassostrea) gigas. Oysters exposed to both stressors contained higher mean DST concentrations (mean ± 1 SE: 173.
View Article and Find Full Text PDFTetrodotoxin (TTX), a potent neurotoxin mostly associated with pufferfish poisoning, is also found in bivalve shellfish. Recent studies into this emerging food safety threat reported TTX in a few, mainly estuarine, shellfish production areas in some European countries, including the United Kingdom. A pattern in occurrences has started to emerge, however the role of temperature on TTX has not been investigated in detail.
View Article and Find Full Text PDFThe production, harvesting and safe consumption of bivalve molluscs can be disrupted by biological hazards that can be divided into three categories: (1) biotoxins produced by naturally occurring phytoplankton that are bioaccumulated by bivalves during filter-feeding, (2) human pathogens also bioaccumulated by bivalves and (3) bivalve pathogens responsible for disease outbreaks. Environmental changes caused by human activities, such as climate change, can further aggravate these challenges. Early detection and accurate quantification of these hazards are key to implementing measures to mitigate their impact on production and safeguard consumers.
View Article and Find Full Text PDFMicrocystins and nodularins, produced naturally by certain species of cyanobacteria, have been found to accumulate in aquatic foodstuffs such as fish and shellfish, resulting in a risk to the health of the seafood consumer. Monitoring of toxins in such organisms for risk management purposes requires the availability of certified matrix reference materials to aid method development, validation and routine quality assurance. This study consequently targeted the preparation of a mussel tissue reference material incurred with a range of microcystin analogues and nodularins.
View Article and Find Full Text PDFBackground: Given the recent detection of tetrodotoxin (TTX) in bivalve molluscs but the absence of a full collaborative validation study for TTX determination in a large number of shellfish samples, interlaboratory assessment of method performance was required to better understand current capabilities for accurate and reproducible TTX quantitation using chemical and immunoassay methods.
Objective: The aim was to conduct an interlaboratory study with multiple laboratories, using results to assess method performance and acceptability of different TTX testing methods.
Methods: Homogenous and stable mussel and oyster materials were assessed by participants using a range of published and in-house detection methods to determine mean TTX concentrations.
Cyanobacterial blooms are often associated with the presence of harmful natural compounds which can cause adverse health effects in both humans and animals. One family of these compounds, known as anatoxins, have been linked to the rapid deaths of cattle and dogs through neurotoxicological action. Here, we report the findings resulting from the death of a dog at a freshwater reservoir in SW England.
View Article and Find Full Text PDFIn September and November 2016, eight marine sampling sites along the coast of the southeastern Gulf of Mexico were monitored for the presence of lipophilic and hydrophilic toxins. Water temperature, salinity, hydrogen potential, dissolved oxygen saturation, inorganic nutrients and phytoplankton abundance were also determined. Two samples filtered through glass fiber filters were used for the extraction and analysis of paralytic shellfish toxins (PSTs) by lateral flow immunochromatography (IFL), HPLC with post-column oxidation and fluorescent detection (FLD) and UHPLC coupled to tandem mass spectrometry (UHPLC-MS/MS).
View Article and Find Full Text PDFHarmful algal blooms are an increasing worldwide threat to the seafood industry and human health as a consequence of the natural production of biotoxins that can accumulate in shellfish. In the Argentine Sea, this has been identified as an issue for the offshore fisheries of Patagonian scallops (), leading to potentially harmful effects on consumers. Here we assess spatial and temporal patterns in marine biotoxin concentrations in Patagonian scallops harvested in Argentinian waters between 2012-2017, based on analyses for paralytic shellfish toxins, lipophilic toxins, and amnesic shellfish toxins.
View Article and Find Full Text PDFAlthough phytoplankton is ubiquitous in the world's oceans some species can produce compounds that cause damaging effects in other organisms. These include the toxins responsible for paralytic shellfish poisoning, which, in UK waters, are produced by dinoflagellates from the Alexandrium genus. Within Great Britain (GB) a monitoring programme exists to detect this harmful genus as well as the Paralytic Shellfish Poisoning (PSP) toxins in the flesh of shellfish from classified production areas.
View Article and Find Full Text PDFMar Drugs
December 2021
Saxitoxins (STXs) are a family of potent neurotoxins produced naturally by certain species of phytoplankton and cyanobacteria which are extremely toxic to mammalian nervous systems. The accumulation of STXs in bivalve molluscs can significantly impact animal and human health. Recent work conducted in the North Sea highlighted the widespread presence of various saxitoxins in a range of benthic organisms, with the common sunstar () demonstrating high concentrations of saxitoxins.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
August 2021
A single laboratory method performance verification is reported for a rapid sensitive UHPLC-MS/MS method for the quantification of eight cyclic imine and two brevetoxin analogues in two bivalve shellfish matrices: mussel (Mytilus edulis) and Pacific oyster (Crassostrea gigas). Targeted cyclic imine analogues were from the spirolide, gymnodimine and pinnatoxin groups, namely 20-Me-SPX-C, 13-desMe-SPX-C, 13,19-didesMe-SPX-C, GYM-A, 12-Me-GYM, PnTx-E, PnTx-F and PnTx-G. Brevetoxin analogues consisted of the shellfish metabolites BTX-B5 and S-desoxy-BTX-B2.
View Article and Find Full Text PDFHarmful algal bloom events are increasing in a number of water bodies around the world with significant economic impacts on the aquaculture, fishing and tourism industries. As well as their potential impacts on human health, toxin exposure from harmful algal blooms (HABs) has resulted in widespread morbidity and mortality in marine life, including top marine predators. There is therefore a need for an improved understanding of the trophic transfer, and persistence of toxins in marine food webs.
View Article and Find Full Text PDFIn the past twenty years marine biotoxin analysis in routine regulatory monitoring has advanced significantly in Europe (EU) and other regions from the use of the mouse bioassay (MBA) towards the high-end analytical techniques such as high-performance liquid chromatography (HPLC) with tandem mass spectrometry (MS). Previously, acceptance of these advanced methods, in progressing away from the MBA, was hindered by a lack of commercial certified analytical standards for method development and validation. This has now been addressed whereby the availability of a wide range of analytical standards from several companies in the EU, North America and Asia has enhanced the development and validation of methods to the required regulatory standards.
View Article and Find Full Text PDFThe IOC-ICES-PICES Harmful Algal Event Database (HAEDAT) was used to describe the diversity and spatiotemporal distribution of harmful algal events along the Atlantic margin of Europe from 1987 - 2018. The majority of events recorded are caused by Diarrhetic Shellfish Toxins (DSTs). These events are recorded annually over a wide geographic area from southern Spain to northern Scotland and Iceland, and are responsible for annual closures of many shellfish harvesting areas.
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