title: Development of Certified Reference Materials for Diarrhetic Shellfish Poisoning Toxins, Part 1: Calibration Solutions.
abstract: Okadaic acid (OA) and its analogs dinophysistoxins-1 (DTX1) and -2 (DTX2) are lipophilic polyethers produced by marine dinoflagellates. These toxins accumulate in shellfish and cause diarrhetic shellfish poisoning (DSP) in humans. Regulatory testing of shellfish is essential to safeguard public health and for international trade. Certified reference materials (CRMs) play a key role in analytical monitoring programs. This paper presents an overview of the interdisciplinary work that went into the planning, production, and certification of calibration-solution CRMs for OA, DTX1, and DTX2. OA and DTX1 were isolated from large-scale algal cultures and DTX2 from naturally contaminated mussels. Toxins were isolated by a combination of extraction and chromatographic steps with processes adapted to suit the source and concentration of each toxin. New 19-epi-DSP toxin analogs were identified as minor impurities. Once OA, DTX1, and DTX2 were established to be of suitable purity, solutions were prepared and dispensed into flame-sealed glass ampoules. Certification measurements were carried out using quantitative NMR spectroscopy and LC-tandem MS. Traceability of measurements was established through certified external standards of established purity. Uncertainties were assigned following standards and guidelines from the International Organization for Standardization, with components from the measurement, stability, and homogeneity studies being propagated into final combined uncertainties.
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Beach
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Sheila
authors.initials: S
authors.lastname: Crain
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Nancy
authors.initials: N
authors.lastname: Lewis
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Patricia
authors.initials: P
authors.lastname: LeBlanc
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: William R
authors.initials: WR
authors.lastname: Hardstaff
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Ruth A
authors.initials: RA
authors.lastname: Perez
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Sabrina D
authors.initials: SD
authors.lastname: Giddings
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Camilo F
authors.initials: CF
authors.lastname: Martinez-Farina
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Roumiana
authors.initials: R
authors.lastname: Stefanova
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Ian W
authors.initials: IW
authors.lastname: Burton
authors.affiliation: Marine Institute, Rinville, Oranmore, Galway County H91 R673, Ireland.
authors.forename: Jane
authors.initials: J
authors.lastname: Kilcoyne
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Jeremy E
authors.initials: JE
authors.lastname: Melanson
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Quilliam
authors.affiliation: National Research Council Canada, Measurement Science and Standards, 1411 Oxford St, Halifax, NS, Canada B3H 3Z1.
authors.forename: Pearse
authors.initials: P
authors.lastname: McCarron
mesh_terms: D000818:Animals; D002138:Calibration; D002853:Chromatography, Liquid / Q000592:standards; D003967:Diarrhea / Q000150:complications*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000592:standards; D008387:Marine Toxins / Q000032:analysis*; D019319:Okadaic Acid / Q000032:analysis* / Q000031:analogs & derivatives; D011714:Pyrans / Q000032:analysis*; D012015:Reference Standards; D012758:Shellfish; D057096:Shellfish Poisoning / Q000150:complications*; D053719:Tandem Mass Spectrometry / Q000592:standards
chemical_list: D008387:Marine Toxins; D011714:Pyrans; D019319:Okadaic Acid; C051904:dinophysistoxin 1; C076221:dinophysistoxin 2