HABs and Biotoxins: Marine Biotoxins - Detection and Analyses

Detection and Analyses of Marine Biotoxins

Detection of Toxins in Seafood and Seawater

Because of the danger associated with marine toxins it is important to understand their cause and effects on consumers of marine resources. For monitoring the safety of seafoods, our current methods are capable of detecting these toxic compounds at the part per million (ppm) level, which is adequate for ensuring the safety of seafoods.

Generally, as compounds move through the food web, they tend to be concentrated. Indeed, the levels of marine biotoxins at the lower trophic levels, i.e., in phytoplankton cell or even dissolved in seawater, are very low. If we are to derive an understanding of the movement of these toxins through the food chain, we must be able to detect and identify these toxins at these lower trophic levels. To accomplish this, more sensitive methods of detection and analysis have to be developed. This will allow us to understand the causes that lead to the blooms of dangerous algae and/or the production of the toxins in the oceanic world. These tools must be capable of determining levels of toxin in the part per billion (ppb) or part per trillion (ppt) range.

Methods of Analyses

Traditionally, marine biotoxins have been detected and quantified or assayed using bioassays--usually the mouse bioassay. For some assays, PSP in particular, this is still the only reliable method available--although that is changing. Animal assays have come under criticism by various groups. In response to these concerns, researchers are trying to find valid, alternative methods for detecting and quantifying biotoxin levels. Currently, three approaches to analyzing biotoxins seem to hold good promise. One is a biochemical ELISA (Enzyme Linked Immunosorbent Assay), a biological method (a receptor binding assay) and an instrumental method (employing high performance liquid chromatography or HPLC with spectrophotometric detection). Both the receptor binding assay and the ELISA measure the activity of toxin in a sample, and the HPLC method is used to detect each type of toxin molecule in a sample.

Please visit the links to the right to read more about detection and methods of analyses.