A new state of the art scanning electron microscope, recently commissioned by the Marine Institute, is set to greatly aid the monitoring and capacity for shellfish safety and complimentary marine environmental research in Ireland.
As the designated National Reference Laboratory (NRL) for monitoring marine biotoxins in shellfish production areas, the Marine Institute carries out a range of seafood safety programmes to ensure that Irish seafood products going to national and international markets adhere to the highest food safety standards. The shellfish safety team oversee the national phytoplankton and biotoxin monitoring programmes and are an important and integral component of providing information on the outbreaks of toxic phytoplankton blooms that can affect aquaculture sites around Ireland.
Joe Silke, manager of the shellfish safety monitoring team explains "new generation scanning electron microscopes have been an incredible step forward in microscopic technology. Our new instrument offers unrivalled imaging performance and provides high resolution capabilities necessary to observe tiny features on the surface of single celled toxic algae. Placing such samples in the machine will allow us extremely high magnification of these features and certainly opens up a new world of what we can examine and analyse."
Although the identification and enumeration of phytoplankton species has been extremely productive using light inverted microscopes since the 1990's, there are limitations of the magnifications and resolution of the images produced. Not all taxonomic features of cells can be identified and with some species it may only be possible to identify down to genus level rather than species level. This is particularly the case with phytoplankton species which are known to produce biotoxins.
"Now the new SEM can provide our team with the ability to conduct research in areas that we haven't had access to in the past. Moving forward, we will now be able to identify phytoplankton species that cause harmful effects that need to differentiate taxonomic features of importance. This will help us provide better advice and expertise in risk assessment and management of coastal shellfisheries, support the national food safety requirements, as well build a forecasting capability to predict the onset and duration of shellfish toxic events," said Joe Silke.
Approximately 2,750 phytoplankton and 3,000 shellfish samples tested annually under the national phytoplankton and biotoxin monitoring programmes. This includes weekly testing of shellfish from all production sites as well as weekly seawater sampling and analysis to detect harmful and toxic species.
"The SEM is therefore vital in providing our teams with the ability to identify phytoplankton cells down to species level, and effectively is essential in helping us expand our services," Joe Silke added.
The SEM will also expand the broader research capabilities of the Marine Institute, with potential applications to marine biodiscovery. This will include "aiding in as yet to be identified novel organisms and their features, as well as in applied aspects of marine environmental research, such as micro-plastics for which there is significant current interest," said Dr Jeff Fisher, Director of Marine Environment and Food Saftey at the Marine Institute.