Fig. 2.

Biotoxin transfer pathways through the marine food web to humans. A biotoxin-producing organism, such as the dinoflagellates Dinophysis acuta or Alexandrium catenella, is bioaccumulated by shellfish, which are apparently not affected by saxitoxin or lipophilic biotoxins. Consumption of the contaminated shellfish is a traditional way of diarrhetic or paralytic poisoning (DSP, PSP). Alternatively, some toxicogenic species attach to surfaces (macrophytes, corals) by an endogenous mucus (e.g. Gambierdiscus, Ostreopsis, Prorocentrum lima). Fragments of corals or macrophytes covered by the microalgae enter the food web through ingestion by herbivorous fish. This is the transmission mechanism of ciguatera fish poisoning (CFP). Certain fishes can also experience some sort of poisoning.