Using two unrelated STX-binding proteins (the rat brain Na channel and a saxiphilin from the xanthid crab Liomera tristis), this study experimentally validated the predicted combined effects of binary and ternary mixtures of paralytic shellfish toxins (PSTs). All toxin dilutions (tritiated saxitoxin ([3H]STX), STX dihydrochloride, neoSTX, dcSTX, and GTX5) were in 0.01 M acetic acid. The L. tristis saxiphilin assay was conducted in high protein binding 96 well filtration plates and the rat brain Na channel binding of [3H]STX was measured using a microtiter plate method.The model predicts the amount of inhibition by toxin mixtures in competitive binding assays from which an IC50 (concentration that inhibits radioligand bindingby 50%) can be calculated. IC50 values and their 95% confidence limits from experimental data were derived using the single site curve equation of Graphpad Prism (Ver 4.0, Graphpad Software, San Diego, CA), with fitting constrained to a slope of 1 and a baseline of 0. To understand how toxin mixtures may act at the Na channel receptor via which PSTs exert their neurotoxicity.To test if the presence of weaker toxins dilutes stronger toxins The strong dominance of a mixture by the most potent toxins has implications for measurement of toxic test samples and for standards that may contain low levels of highly potent bioactive impurities.

In this study, a microtitre plate binding assay using a saxiphilin isoform [3H]STX from the centipede Ethmostigmus rubripes, was challenged with differing conditions of salt concentration and identity, pH and the addition of non-toxic extracts of commercial shellfish.Elements present (Na, K, Mg, Ca, Zn, Ni, Mn, Cr, Sr, Mo, Al, V, Fe, Cu, Pb, Co) in the shellfish extracts (green lipped mussel, Perna canalicularis; Sydney rock oyster, Saccostrea glomerata; and pipis, Donax deltoides) were measured by inductively coupled plasma spectroscopy. The effects upon the assay by the four most common salts of these elements, NaCl, KCl, CaCl2 and MgCl2 were studied by varying their concentrations (0-800 mM).The effect of pH upon the assay was measured by replacing the assay buffer in standard conditions with a buffer mixture of Tris (20 mM) -Mes (10 mM) -acetic acid (10 mM), adjusted with tetramethylammonium hydroxide or HCl to indicated pH which ranged from 3.4 to 9.0. To investigate the microtitre plate saxiphilin assay's ability to deal with potential interfering compounds from shellfish extracts, and the effect of acidic pH necessary for toxin stability when extracting PSTs from shellfish.

The state of Washington routinely experiences seasonal restrictions on commercial and recreational shellfish harvest due to two toxic phytoplankton syndromes, Paralytic Shellfish Poisoning (PSP) and Amnesic Shellfish Poisoning (ASP), which is often referred to as Domoic Acid Poisoning (DAP). The biotoxin that causes PSP temporarily interferes with the transmission of nerve impulses in warm-blooded animals, causing symptoms in humans such as, numbness and tingling of the lips, tongue, face and extremities, difficulty talking, breathing, swallowing and muscle incoordinations. Symptoms develop quickly (within 1-2 hours of consumption) and can result in death. The species that causes PSP in Washington state marine waters is Alexandrium catenella. Alexandrium is usually present in small numbers; however, when environmental conditions are optimum, rapid reproduction occurs. Filter-feeding shellfish can accumulate the toxins to dangerous levels during these "blooms". Domoic acid poisoning is caused by eating fish, shellfish or crab containing the toxin. Symptoms include vomiting, nausea, diarrhea and abdominal cramps within 24 hours of digestion. In severe cases, neurological symptoms develop within 48 hours and include headache, dizziness, confusion, disorientation, loss of short-term memory, motor weakness, seizures, profuse respiratory secretions, cardiac arrhythmias, coma and possibly death. Domoic acid produced by marine diatoms of the genus Pseudo-nitzschia, was first detected on the Pacific coast in 1991 when several pelican and cormorant deaths were link to domoic acid in anchovies. The Washington State Department of Health routinely monitors for PSP and ASP in shellfish from areas throughout the state. Areas are closed for harvest of molluscan shellfish when PSP toxin levels are equal to or exceed 80 ug toxin/100 grams shellfish tissue. Molluscan shellfish areas are closed when domoic acid (DA) levels reach 15 ppm in a composite sample of six shellfish (this level was changed to 20 ppm in 2001), whereas Dungeness crab areas are closed when DA levels reach 30 ppm in three of six individual crab viscera.

The state of Washington routinely experiences seasonal restrictions on commercial and recreational shellfish harvest due to two toxic phytoplankton syndromes, Paralytic Shellfish Poisoning (PSP) and Amnesic Shellfish Poisoning (ASP), which is often referred to as Domoic Acid Poisoning (DAP). The biotoxin that causes PSP temporarily interferes with the transmission of nerve impulses in warm-blooded animals, causing symptoms in humans such as, numbness and tingling of the lips, tongue, face and extremities, difficulty talking, breathing, swallowing and muscle incoordinations. Symptoms develop quickly (within 1-2 hours of consumption) and can result in death. The species that causes PSP in Washington state marine waters is Alexandrium catenella. Alexandrium is usually present in small numbers; however, when environmental conditions are optimum, rapid reproduction occurs. Filter-feeding shellfish can accumulate the toxins to dangerous levels during these "blooms". Domoic acid poisoning is caused by eating fish, shellfish or crab containing the toxin. Symptoms include vomiting, nausea, diarrhea and abdominal cramps within 24 hours of digestion. In severe cases, neurological symptoms develop within 48 hours and include headache, dizziness, confusion, disorientation, loss of short-term memory, motor weakness, seizures, profuse respiratory secretions, cardiac arrhythmias, coma and possibly death. Domoic acid produced by marine diatoms of the genus Pseudo-nitzschia, was first detected on the Pacific coast in 1991 when several pelican and cormorant deaths were link to domoic acid in anchovies. Therefore, this dataset only contains PSP data for 1957-1988. The Washington State Department of Health routinely monitors for PSP and ASP in shellfish from areas throughout the state. Areas are closed for harvest of molluscan shellfish when PSP toxin levels are equal to or exceed 80 ug toxin/100 grams shellfish tissue. Molluscan shellfish areas are closed when domoic acid (DA) levels reach 15 ppm in a composite sample of six shellfish (this level was changed to 20 ppm in 2001), whereas Dungeness crab areas are closed when DA levels reach 30 ppm in three of six individual crab viscera.

Sodium channel and saxiphilin radioreceptor assays were carried out to determine whether paralytic shellfish toxins were present in the gut contents, liver, blood, bile and urine of a male who died in 2000 after consuming a crab, Zosimus aeneus. A second uneaten specimen from the meal was also tested. HPLC analysis of toxin profiles was also carried out on the gut content and urine of the victim, and the uneaten crab specimen.A dose likely to have been consumed by the victim was calculated (between 1 and 2 µg STX equivalents/kg). To use sodium channel and saxiphilin receptor assays, and confirm the results by HPLC analysis, to identify paralytic shellfish toxins in gut contents, various body fluids and tissues obtained post-mortem from the victim. Proportions of individual paralytic shellfish toxin profiles (mol% of STX, dcSTX, GTX2, GTX3, NEO) to total toxin content of the samples are given where discernable by HPLC analysis.

The state of Washington routinely experiences seasonal restrictions on commercial and recreational shellfish harvest due to two toxic phytoplankton syndromes, Paralytic Shellfish Poisoning (PSP) and Amnesic Shellfish Poisoning (ASP), which is often referred to as Domoic Acid Poisoning (DAP). The biotoxin that causes PSP temporarily interferes with the transmission of nerve impulses in warm-blooded animals, causing symptoms in humans such as, numbness and tingling of the lips, tongue, face and extra difficulty talking, breathing, swallowing and muscle incoordinations. Symptoms develop quickly (within 1-2 hours of consumption) and can result in death. The species that causes PSP in Washington state marine waters is Alexandrium catenella. Alexandrium is usually present in small numbers; however, when environmental conditions are optimum, rapid reproduction occurs. Filter-feeding shellfish can accumulate the toxins to dangerous levels during these "blooms". Domoic acid poisoning is caused by eating fish, shellfish or crab containing the toxin. Symptoms include vomiting, nausea, diarrhea and abdominal cramps within 24 hours of digestion. In severe cases, neurological symptoms develop within 48 hours and include headache, dizziness, confusion, disorientation, loss of short-term memory, motor weakness, seizures, profuse respiratory secretions, cardiac arrhythmias, coma and possibly death. Domoic acid produced by marine diatoms of the genus Pseudo-nitzschia, was first detected on the Pacific coast in 1991 when several pelican and cormorant deaths were link to domoic acid in anchovies. The Washington State Department of Health routinely monitors for PSP and ASP in shellfish from areas throughout the state. Areas are closed for harvest of molluscan shellfish when PSP toxin levels are equal to or exceed 80 ug toxin/100 grams shellfish tissue. Molluscan shellfish areas are closed when domoic acid (DA) levels reach 15 ppm in a composite sample of six shellfish (this level was changed to 20 ppm in 2001), whereas Dungeness crab areas are closed when DA levels reach 30 ppm in three of six individual crab viscera.

The state of Washington routinely experiences seasonal restrictions on commercial and recreational shellfish harvest due to two toxic phytoplankton syndromes, Paralytic Shellfish Poisoning (PSP) and Amnesic Shellfish Poisoning (ASP), which is often referred to as Domoic Acid Poisoning (DAP). The biotoxin that causes PSP temporarily interferes with the transmission of nerve impulses in warm-blooded animals, causing symptoms in humans such as, numbness and tingling of the lips, tongue, face and extremities, difficulty talking, breathing, swallowing and muscle incoordinations. Symptoms develop quickly (within 1-2 hours of consumption) and can result in death. The species that causes PSP in Washington state marine waters is Alexandrium catenella. Alexandrium is usually present in small numbers; however, when environmental conditions are optimum, rapid reproduction occurs. Filter-feeding shellfish can accumulate the toxins to dangerous levels during these "blooms". Domoic acid poisoning is caused by eating fish, shellfish or crab containing the toxin. Symptoms include vomiting, nausea, diarrhea and abdominal cramps within 24 hours of digestion. In severe cases, neurological symptoms develop within 48 hours and include headache, dizziness, confusion, disorientation, loss of short-term memory, motor weakness, seizures, profuse respiratory secretions, cardiac arrhythmias, coma and possibly death. Domoic acid produced by marine diatoms of the genus Pseudo-nitzschia, was first detected on the Pacific coast in 1991 when several pelican and cormorant deaths were link to domoic acid in anchovies. The Washington State Department of Health routinely monitors for PSP and ASP in shellfish from areas throughout the state. Areas are closed for harvest of molluscan shellfish when PSP toxin levels are equal to or exceed 80 ug toxin/100 grams shellfish tissue. Molluscan shellfish areas are closed when domoic acid (DA) levels reach 15 ppm in a composite sample of six shellfish (this level was changed to 20 ppm in 2001), whereas Dungeness crab areas are closed when DA levels reach 30 ppm in three of six individual crab viscera.

Lipophilic shellfish toxins comprise an extensive suite of compounds including those associated with the human syndromes known as diarrhetic shellfish poisoning (DSP) and azaspiracid shellfish poisoning (AZP). As a result of recent bloom events and subsequent human intoxications in Washington State (USA) due to DSP, there is a critical and urgent need for State public health officials to be able to monitor and accurately quantify harmful algal bloom (HAB) species associated with DSP and azaspiracid shellfish poisoning (AZP) and their toxins. There is now evidence that lipophilic toxins associated with DSP and AZP are present in water and/or shellfish, including oysters and mussels from Puget Sound and razor clams from the WA coast.Tight partnership with WDOH, the SoundToxins program, Olympic Region Harmful Algal Blooms (ORHAB) partnership, and Puget Sound shellfish growers (including the Jamestown S’Klallam tribe and other tribal representatives) will facilitate the study of the seasonal variability of lipophilic toxins and toxin-producing species at 10 geographically-distinct sites within Washington State waters where seawater or shellfish have recently been contaminated with these toxins. Stakeholder support throughout the project will ensure the transition of this project to the State at the end of 3 years as we have successfully demonstrated with ORHAB. Implementing routine lipophilic biotoxin monitoring will be a critical first step towards ensuring public safety while also enabling Washington State shellfish growers to sell their product to the European Union once trade is re-established. Contains information regarding toxin producing species and toxin measurements in shellfish and seawater samples. Also includes associated environmental data.

This data set is comprised of results associated with a multi-stage experimental study to determine the effects of paralytic shellfish toxin ingestion by Common Murres (Uria aalge) conducted in 2021-2022. Data is comprised of eight spreadsheets covering each phase of the study including specific bird dosing data, behavioral observation data, foraging trial data, and tissue testing results for Saxitoxin (STX) and related congeners.