Risk ciguatera

From the human perspective, HABs are problematic because they cause (1) risks to human health, (2) loss of natural or cultured seafood resources, (3) impairment of tourism and recreational activities, and (4) damage to noncommercial marine resources and wildlife. Exposure pathways include (1) consumption of toxic shellfish that have accumulated phytoplankton toxins filtered from the water, (2) consumption of tropical fish that have accumulated phytoplankton toxins (ciguatera), (3) inhalation of aerosolized toxins ejected from the sea surface, and (4) skin contact resulting in irritations due to allergy-like reactions. Harmful health effects from acute exposures have been relatively well studied. Less well known are the health effects resulting from chronic exposures to low toxin levels. This is of particular concern with regards to marine mammals and seabirds. 

Lehane, L. and Lewis, R. J. (2000). Ciguatera Recent advances but the risk remains. Int. J. Food Microbiol. 61,91-125. 

While consumption of contaminated fish is the primary risk factor for ciguatera, transmission has also been shown to occur via consumption of breast milk from an affected mother to her infant and across the placenta to the embryo/fetus [106-108]. Numerous studies have attempted to identify factors that put exposed persons at increased risk for symptomatic ciguatera, although the outcomes and risk factors measured have differed widely between these studies. One study reports an association between illness and age [65], but three other studies report no association [66,78,80] in addition, cases have been reported among persons from less than 1 to 83 years of age [57]. Similarly, Bagnis... 

If this occurs, more specific regulatory intervention will not be far behind. Public health and regulatory measures to control ciguatera should consider the relative value of a fish diet compared to the risk of ciguatera, the economic and social importance of fish harvesting to a community, the anticipated intervention when toxic fish are identified (particularly if toxic fish represent a considerable portion of the total harvest), and guidelines for relaxation of specific restrictions (e.g., import or export restrictions) once implemented. 

Lehane, L. Ciguatera fish poisoning a review in a risk assessment framework. National Office of Animal Plant Health, Agriculture, Fisheries and Forestry, Canherra, Anstralia, 1999, p. 82. 

Ciguatera is a consistently underappreciated and underreported problem. Many affected communities are at marginal socioeconomic or subsistence levels. Tourist hotels in tropical regions can afford to import their fish (and, in areas of high endemicity, such as the Virgin Islands, almost all do so), while local populations remain at risk. The public health impact of ciguatera is particularly high in remote atoll countries of the Pacific where daily intake of reef fish may exceed 100 g/person per day (Lewis, 1992) and where fish represent a major protein source that cannot be fully exploited,... 

Despite frequent occurrences of ciguatera toxins in many parts of the world, this poisoning is rarely fatal, because of the low concentration of the toxin in fish flesh. Maybe for this reason very few specific regulations exist for ciguatera toxins [6]. In some areas, public health measures have been taken that include bans on the sale of high risk fish from known toxic locations. Such bans have been used in American Samoa, Queensland, French Polynesia, Fiji, Hawaii, and Miami. The bans were apparently with some success but with attendant economic loss [38]. 

Boada, L.D., Zumbado, M., Luzardo, O.P., Almeida-Gonzalez, M., Plakas, S.M., Granade, H.R., Abraham, A., Jester, E.L.E., and Dickey, R.W. (2010) Ciguatera fish poisoning on the West Africa coast An emerging risk in the Canary Islands (Spain). Toxicon, 56, 1516-1519. 

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