Browsing Marine Environment & Food Safety Services by Author "Keady, E."
Molecular methods for monitoring harmful algal bloom speciesKeady, E.; Maher, M. (Marine Institute, 2009)Shellfish production can be adversely affected by the presence of harmful microalgae (HABs). Toxins produced by Dinophysis, Alexandrium and Pseudo-nitzschia species can accumulate in shellfish and have the potential to cause serious human illness. In order to satisfy EU legislative requirements pertaining to the production and export of shellfish (EC Hygiene Regulations 2004, No. 853/2004 and No. 854/2004, which replaced the EU Shellfish Hygiene Directive 91/492/EEC in January 2006), monitoring the presence of harmful algal species and biotoxins in coastal waters is performed by EU member states. Routine microscopic monitoring methods are unable to identify certain toxic species, in particular, Alexandrium and Pseudo-nitzschia spp. Electron microscopy is required for species identification and this technique cannot be integrated into a routine monitoring programme. Molecular techniques utilise unique sequence signatures within microorganism genomes for species specific identification. Molecular methods applied for the identification and quantification of HAB species include Fluorescent in-situ hybridisation (FISH) and in-vitro amplification based methods, in particular, real-time PCR.
The use of immunoassay technology in the monitoring of algal biotoxins in farmed shellfishWilson, A.; Keady, E.; Silke, J.; Raine, R. (International Society for the Study of Harmful Algae and Intergovernmental Oceanographic Commission of UNESCO, 2013)The use of immunoassay technology as an adjunct method for monitoring biotoxins in shellfish was investigated at aquaculture sites in Killary Harbour, Ireland, during summer 2009. Sub-samples of mussels (Mytilus edulis) were taken from batches collected as part of the Irish National Phytoplankton and Biotoxin Monitoring Programme (NMP). Samples were analysed for Diarrhetic Shellfish Poisoning (DSP) toxins using a commercially available ELISA immunoassay kit. The results were compared with those obtained by chemical (liquid chromatography with mass spectrometry, LC-MS) and biological (mouse bioassay, MBA) methods from the monitoring programme. DSP levels increased in late June 2009 over the European Union maximum permitted level of 0.16 μg g-1 and positive MBA results led to harvest closures. This event was reflected in both the chemical and immunoassay results, where a positive relationship between them was found.