This letter is in regards to the paper, “Quantitative evaluation of commercially available test kit for ciguatera in fish” [1]. We were compelled to respond because the entire premise of this paper is flawed, thus invalidating its stated conclusions. The data presented in the paper is derived from the opinions of four independent readers who evaluated identical Cigua-Check ? test sticks to screen fish samples for ciguatoxin (CTX), the results of which were then compared with corresponding samples tested in a non-specific bioassay with questionable statistics (see Table 1 [1]). In addition to several factual errors presented in the paper, we have identified several issues with this study, such as insufficient detail and questionable data analyses, that make its interpretations unreliable.
P. Bienfang, S. DeFelice and A. Dowling, “Quantitative Evaluation of Commercially Available Test Kit for Ciguatera in Fish,” Food Nutrition Sciences, Vol. 2, No.6, 2011, pp. 594-598.
A. Caillaud, P. de la Iglesia, H. T. Darius, S. Pauillac, K. Aligizaki, S. Fraga, M. Chinain and J. Diogène, “Update on Methodologies Available for Ciguatoxin Determination: Perspectives to Confront the Onset of Ciguatera Fish Poisoning in Europe,” Marine Drugs, Vol. 8, No. 6, 2010, pp. 1838-1907. doi:10.3390/md8061838
R. L. Manger, L. S. Leja, S. Y. Lee, J. M. Hungerford, and M. M. Wekell, “Tetrazolium-Based Cell Bioassay for Neurotoxins Active on Voltage-Sensitive Sodium Channels: Semiautomated Assay for Saxitoxins, Brevetoxins, and Ciguatoxins,” Analytical Biochemistry, Vol. 214, No. 1, 1993, pp. 190-194. doi:10.1006/abio.1993.1476
R. L. Manger, L. S. Leja, S. Y. Lee, J. M. Hungerford, Y. Hokama, R. W. Dickey, H. R. Granade, R. Lewis, T. Yasumoto and M. M. Wekell, “Detection of Sodium Channel Toxins: Directed Cytotoxicity Assays of Purified Ciguatoxins, Brevetoxins, Saxitoxins, and Seafood Extracts,” Journal of AOAC International, Vol. 78, No. 2, 1995, pp. 521-527.
K. Kogure, M. Tamplin, U. Simidu and R. Colwell, “A Tissue Culture Assay for Tetrodotoxin, Saxitoxin and Related Toxins,” Toxicon, Vol. 26, No. 2, 1988, pp. 191-197. doi:10.1016/0041-0101(88)90171-7
J. Jellett, L. Marks, J. Stewart, M. Dorey, W. WatsonWright and J. Lawrence, “Paralytic Shellfish Poison (Saxitoxin Family) Bioassays: Automated Endpoint Determination and Standardization of the in Vitro Tissue Culture Bioassay, and Comparison with the Standard Mouse Bioassay,” Toxicon, Vol. 30, No. 10, 1992, pp. 1143-1156. doi:10.1016/0041-0101(92)90430-D
J. Jellett, J. Stewart and M. Laycock, “Toxicological Evaluation of Saxitoxin, Neosaxitoxin, Gonyautoxin II, Gonyautoxin II Plus III and Decarbamoylsaxitoxin with the Mouse Neuroblastoma Cell Bioassay,” Toxicol in Vitro, Vol. 9, No. 1, 1995, pp. 57-65. doi:10.1016/0887-2333(94)00194-Y
W. A. Catterral and M. Gainer, “Interaction of Brevetoxin A with a New Receptor Site on the Sodium Channel,” Toxicon, Vol. 23, 1985, pp. 497-504. doi:10.1016/0041-0101(85)90034-0
R. Dickey, E. Jester, R. Granade, D. Mowdy, C. Moncreiff, D. Rebarchik, M. Robl, S. Musser and M. Poli, “Monitoring Brevetoxins during a Gymnodinium breve Red Tide: Comparison of Sodium Channel Specific Cytotoxicity Assay and Mouse Bioassay for Determination of Neurotoxic Shellfish Toxins in Shellfish Extracts,” Natural Toxins, Vol. 7, No. 4, 1999, pp. 157-165. doi:10.1002/(SICI)1522-7189(199907/08)7:4 3.0.CO;2-#
M. A. Friedman, L. E. Fleming, M. Fernandez, P. Bienfang, K. Schrank, R. Dickey, M.-Y. Bottein, L. Backer, R. Ayyar, R. Weisman, S. Watkins, R. Granade and A. Reich, “Ciguatera Fish Poisoning: Treatment, Prevention and Management,” Marine Drugs, Vol. 6, No. 3, 2008, pp. 456-479. doi:10.3390/md6030456
E. Caňete and J. Diogène, “Comparative Study of the Use of Neuroblastoma Cells (Neuro-2a) and Neuroblastoma x Glioma Hybrid Cells (NG108-15) for the Toxic Effect Quantification of Marine Toxins,” Toxicon, Vol. 52, No. 4, 2008, pp. 541-550. doi:10.1016/j.toxicon.2008.06.028
A. Caillaud, E. Caňete, P. de la Iglesia, G. Giménez and J. Diogène, “Cell-Based Assay Coupled with Chromatographic Fractioning: A Strategy for Marine Toxins Detection in Natural Samples,” Toxicol in Vitro, Vol. 23, No. 8, 2009, pp. 1591-1596. doi:10.1016/j.tiv.2009.08.013
R. W. Dickey, “Ciguatera Toxins: Chemistry, Toxicology, and Detection,” In: L. M. Botana, Ed., Seafood and Freshwater Toxins: Pharmacology, Physiology, and Detection, 2nd Edition, CRC Press, Boca Raton, 2008, pp. 479-500. doi:10.1201/9781420007541.ch22
C. Tomlinson, J. Marshall and J. E. Ellis, “Comparison of Accuracy and Certainty of Results of Six Home Pregnancy Tests Available Over-the-Counter,” Current Medical Research and Opinion, Vol. 24, No. 6, 2008, pp. 1645-1649. doi:10.1185/03007990802120572
S. A. Butler, S. A. Khanlian and L. A. Cole, “Detection of Early Pregnancy Forms of Human Chorionic Gonadotropin by Home Pregnancy Test Devices,” Clinical Chemistry, Vol. 47, 2001, pp. 2131-2136.
L. A. Cole, “The Utility of Six Over-the-Counter (Home) Pregnancy Tests,” Clinical Chemistry and Laboratory Medicine, Vol. 49, No. 8, 2011, pp. 1317-1322. doi:10.1515/cclm.2011.211
S. Davies, F. Byrn and L. A. Cole, “Human Chorionic Gonadotropin Testing for Early Pregnancy Viability and Complications,” Clinics in Laboratory Medicine, Vol. 23, No. 2, 2003, 257-264. doi:10.1016/S0272-2712(03)00026-X
B. G. Valanis and C. S. Perlman, “Home Pregnancy Testing Kits: Prevalence of Use, False-Negative Rates, and Compliance with Instructions,” American Journal of Public Health, Vol. 72, No. 9, 1982, pp. 1034-1036. doi:10.2105/AJPH.72.9.1034
Y. Hokama, “A Rapid, Simplified Enzyme Immunoassay Stick Test for the Detection of Ciguatoxin and Related Polyethers from Fish Tissues,” Toxicon, Vol. 23, No. 6, 1985, pp. 939-946. doi:10.1016/0041-0101(85)90386-1
Y. Hokama, A. H. Banner and D. B. Boylan, “A Radioimmunoassay for the Detection of Ciguatoxin,” Toxicon, Vol. 15, No. 4, 1977, pp. 317-325. doi:10.1016/0041-0101(77)90014-9
Y. Hokama, W. E. Takenaka, K. L. Nishimura and J. S. M. Ebesu, “A Simple Membrane Immunobead Assay (MIA) for Detecting Ciguatoxin and Related Polyethers From Human Ciguatera Intoxication and Natural Reef Fishes,” Journal of AOAC International, Vol. 81, No. 4, 1998, pp. 727-735.
D. L. Park, “Evolution of Methods for Assessing Ciguatera Toxins in Fish,” Reviews of Environmental Contamination & Toxicology, Vol. 136, 1994, pp. 1-20. doi:10.1007/978-1-4612-2656-7_1
R. W. Dickey, H. R. Granade and F. D. McClure, “Evaluation of a Solid-Phase Immunobead Assay for Detection of Ciguatera-Related Biotoxins in Caribbean Finfish,” Memoirs of the Queensland Museum, Vol. 34, 1994, pp. 481-488.
A.-M. Legrand, T. Teai, P. Cruchet, M. Satake, K. Murata and T. Yasumoto, “Two Structural Types of Ciguatoxins Involved in Ciguatera Fish Poisoning in French Polynesia,” In: B. Reguera, J. Blanco, M. L. Fernandez and T. Wyatt, Eds., Harmful Algae, Xunta de Galicia and InterGovernmental Commission of UNESCO, 1998, pp. 473-475.
S. Pauillac, M. Sasaki, J. Naar, M. Inoue, P. Branaa, P. Cruchet, M. Chinain and A.-M. Legrand, “Immunochemical Methods for Ciguatoxins Detection in Pacific Herbivorous and Carnivorous Fish,” In: B. Seret and J.-Y. Sire, Eds., Society of French Ichthyologists, Paris, Proceedings of the 5th Indo-Pacifique Fisheries Conference, Noumea, 1999, pp. 759-773.
C. K. Wong, P. Hung, K. L. Lee and K. M. Kam, “Study of an Outbreak of Ciguatera Fish Poisoning in Hong Kong,” Toxicon, Vol. 46, 2005, pp. 563-571. doi:10.1016/j.toxicon.2005.06.023
J. S. Yoshikawa Ebesu and Y. Hokama, “Study of an Outbreak of Ciguatera Fish Poisoning in Hong Kong,” Toxicon, Vol. 48, No. 4, 2006, pp. 467-469. doi:10.1016/j.toxicon.2006.06.006
Y. Bentur and E. Spanier, “Ciguatoxin-Like Substances in Edible Fish on the Eastern Mediterranean,” Clinical Toxicology, Vol. 45, 2007, pp. 695-700. doi:10.1080/15563650701502865
Y. Hokama, “Simplified Solid-Phase Immunobead Assay for Detection of Ciguatoxin and Related Polyethers in Fish Tissue,” Journal of Clinical Laboratory Analysis, Vol. 4, No. 3, 1990, pp. 423-235. doi:10.1002/jcla.1860040313
J.-L. Pérez-Arellano, O. P. Luzardo, A. P. Brito, M. H. Cabrera, M. Zumbado, C. Carranza, A. Angel-Moreno, R. W. Dickey, and L. D. Boada, “Ciguatera Fish Poisoning, Canary Islands,” Emerging Infectious Diseases, Vol. 11, No. 12, 2005, pp. 1981-1982. doi:10.3201/eid1112.050393
H. D. Luo, Y. Y. Bai and N. Zhou, “Study of Three Ciguatera Fish Poisoning Cases in Xiamen City, in 2005,” Chinese Journal of Preventive Medicine, Vol. 45, No. 6, 2011, pp. 512-515.
C. E. Campora, Y. Hokama and J. S. M. Ebesu, “Comparative Analysis of Purified Pacific and Caribbean Ciguatoxin Congeners and Related Marine Toxins Using a Modified ELISA Technique,” Journal of Clinical Laboratory Analysis, Vol. 20, No. 3, 2006, pp. 121-125. doi:10.1002/jcla.20113
J. Dierking and C. E. Campora, “Ciguatera in the Introduced Fish Cephalopholis argus (Serranidae) in Hawaii and Implications for Fishery Management,” Pacific Science, Vol. 63, No. 2, 2009, pp. 193-204. doi:10.2984/049.063.0203