Playtoxin (PLTX) has been identified in a variety of sources and from diverse positions in the ecosystem. PLTX and an array of analogues have been identified in various coral reef animals, including fish. PLTX and its 42-hydroxyl derivative were isolated from the marine cyanobacterium Trichodesmium. The possibility of PLTX accumulation in the food web via Ostreopsis has been explored. A primary concern related to the entrance of biotoxins into the ecosystem is the potential human exposure via ingestion of contaminated seafood. The presence of PLTX or PLTX-like compounds has been associated with several cases of seafood intoxications. To fully understand the toxicological risk of PLTX in the food web, in vivo studies are required. The study of the toxicological effects of PLTX after oral exposure is highly relevant to understanding the risks of PLTX as a food contaminant. Studies describing parenteral administration of PLTXs represent the majority of the toxicity data available for this family of compounds.