ciguatoxins and Poisoning

Environmental poisoning is most commonly associated with chronic long-term exposure to toxins rather than to acute exposure. Such repeated exposure to sublethal doses of compounds and elements presents problems in risk assessment. This is primarily because the data are unavailable to describe relationships between dose and effect at lower levels of exposure to toxins. Bioavailability of toxins also presents a problem because the data on bioavailability are sparse and seldom as high as the default of 100% bioavailability commonly used in risk assessment. Examples are presented of two toxins: arsenic as an elemental anthropogenic and geologic poison and ciguatoxin, a polyether ladder compound, as a toxin produced naturally by dinoflagellates. Bioavailability drives the toxicity of arsenic from contaminated sites, whereas tissue accumulation drives the toxicity of ciguatoxin. Considerable benefit is derived from the harmonization of regulatory processes where there is linkage of health and environmental factors in the derivation of credible risk assessment.

Topics: Arsenic; Ciguatoxins; Environmental Pollutants; Humans; Poisoning; Poisons

Topics: Animals; Ciguatera Poisoning; Ciguatoxins; Fishes, Poisonous; Humans; New Caledonia; Poisoning

Ciguatera fish poisoning is the most common form of toxin-related food poisoning in the United States. Originating from dinoflagellates living on coral reefs, it is spread up the food and affects humans who ingest the ciguatoxic fish. Ciguatera is primarily endemic in tropical regions of the world. It is a self-limiting disease that presents with characteristic gastrointestinal, neurological, and cardiovascular symptoms. Recent advances in testing procedures and symptom recognition has improved ciguatoxin identification and clinical management. However, there is still a need for better diagnostic, preventive, and reporting protocols to more accurately study and understand this diverse and temporarily debilitating clinical syndrome.

Topics: Ciguatera Poisoning; Ciguatoxins; Heart; Humans; Poisoning

Serranidae and Labridae fish caught in 1993 at Alijos Rocks, 300 miles off East Magdalena Bay, Southern Baja California, caused severe illness of a fishing boat crew. The described symptoms resembled those of ciguatera. The presence of ciguatera-like toxins was confirmed on extracts from these fish using the mouse bioassay procedure, showing activities between 220 to 390 mouse units (M.U.). The founding of ciguatoxin at Alijos Rocks 24 degrees 57' N, 115 degrees 45' W) extends to the northeast its geographical distribution in the Pacific and locates the outbreak near the continental coastline.

Topics: Adult; Animals; Bass; Biological Assay; Ciguatera Poisoning; Ciguatoxins; Humans; Mexico; Mice; Pacific Islands; Poisoning; Seafood