The Canary Islands government has approved a grant of more than €100,000 for a university to allow it to carry out tests to detect ciguatoxin in fish.

The award of €105,000 ($114,900) to the University Institute of Animal Health and Food Safety (IUSA) will enable it to meet the costs of doing such laboratory tests.

Ciguatoxin is produced by microalgae called Gambierdiscus spp. The toxins move through the food chain until the contaminated fish are caught and served to people. Ciguatera food poisoning is associated with consumption of large predator fish that have accumulated the toxins by feeding on smaller contaminated coral reef fish. The toxin does not affect the appearance, odor or taste of the fish and is not destroyed by cooking, refrigeration or freezing.

Preventing ciguatera poisoning
The IUSA at the University of Las Palmas de Gran Canaria (ULPGC) is an approved center by the European Reference Laboratory (EURL) for marine biotoxins to carry out tests to determine if ciguatoxin is present in fish samples. The EURL for marine biotoxins is the Spanish Agency for Food Safety and Nutrition (AESAN).

The agencies that handle fisheries and public health in the Canary Islands are responsible for controlling and monitoring fishing activities and the first points of sale in the region to prevent poisoning with ciguatera toxin. To do this, analysis is carried out to detect the toxin in those species of fish that are possible carriers and that meet previously set conditions of size and weight.

It is important to determine with certainty the presence and evolution of ciguatoxin in species that could be carriers to protect the health of consumers. It is also crucial to minimize repercussions that stopping certain catches and sending them for lab tests could have for the fishing sector, according to the Canary Islands government.

In February this year, Canary Islands fishery authorities and the Spanish Environment Protection Service (SEPRONA) of the Guardia Civil seized 25 kilograms of grouper that lacked documentation on provenance and had not undergone checks for ciguatera before commercialization. The specimen was obtained after an inspection at a restaurant in San Sebastián de la Gomera.

Attention on a growing problem
Previous research by IUSA scientists found the first documented outbreak in the Canary Islands was in 2004, when nine people became intoxicated. As of 2019, 19 ciguatera outbreaks had been confirmed, affecting 117 people.

Prevalence in some species of fish in the Canary Islands has been calculated at between 10.5 and 13 percent. In 2015 a surveillance network was created and ciguatera was listed as a notifiable disease in the Canary Islands.

IUSA-ULPGC is part of the EuroCigua project co-financed by the European Food Safety Authority (EFSA) and coordinated by AESAN until September 2020. The objective is to determine prevalence of ciguatera in Europe and to characterize the risk, developing analytical methods to detect the presence of specimens contaminated by ciguatoxins.

Ciguatera is the most common type of marine biotoxins food poisoning worldwide with an estimated 10,000 to 50,000 people suffering from the disease annually, according to AESAN.

From 2012 to 2018, 167 cases from 23 outbreaks have been notified in France, Germany, Portugal and Spain.

People who have ciguatera may experience nausea, vomiting, and neurologic symptoms such as tingling fingers or toes. They may also find that cold things feel hot and hot things feel cold. Symptoms occur within one to 24 hours of eating a toxic fish and usually go away in days or weeks but can last for years.

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