Marine toxins (biotoxins) are naturally occurring chemicals, mostly caused by certain types of toxic algae, but also by bacteria. These toxins can accumulate in fish and shellfish and present a human health hazard (WHO, no date). When people consume such contaminated aquatic products, depending on the toxins, they can evoke a variety of gastrointestinal and neurological illnesses (paralytic shellfish poisoning, amnesic shellfish poisoning, diarrhoeic shellfish poisoning, neurotoxic shellfish poisoning, azaspiracid shellfish poisoning and ciguatera poisoning).