We are improving detection of species of the toxin-producing alga Alexandrium in the field by producing highly portable, efficient, and effective biosensors. Alexandrium can be hard to identify and sample, and available detection methods are lab-based, costly, or cannot reliably distinguish between toxic and non-toxic species. Our rapid, low-cost and easy-to-use detection devices will be an important advance for volunteer and state harmful algal bloom monitoring programs.
Why We Care
Paralytic shellfish poisoning (PSP) syndrome is a worldwide human health problem. PSP is caused by toxins of the marine dinoflagellate Alexandrium. The Gulf of Maine historically has toxic Alexandrium blooms and PSP outbreaks each year that force closure of shellfish harvests. The regional economy loses hundreds of jobs and millions of dollars. Alexandrium can be hard to identify and sample as they occur in low population numbers while producing significant levels of toxin. Current detection methods (e.g. light microscopes) cannot always distinguish toxic from non-toxic species and most cell identification methods are lab-based, expensive, time-consuming, and require special training making them impractical for volunteer or state harmful algal bloom (HAB) monitoring programs. New tools for fast, early warning of increased HAB cell numbers will help preserve the safe harvest of shellfish from toxin-free areas enabling agencies to make targeted decisions to close certain shellfish beds rather than more general, coast-wide closures.
The dynamic nature of HABs can result in an unexpected emergence of dangerous toxin levels in areas that are otherwise considered “low-risk” for toxin intrusion. Consequently, they may receive little or no regular testing. Better, faster, monitoring tools for HAB species should maximize safe harvest areas, and protect public health, which in turn will prevent negative economic impacts on the shellfish industry.
What We Are Doing
We are combining peptide nucleic acid probes and portable surface plasmon resonance biosensor technology to develop molecular probes with greater sensitivity and new capabilities for direct detection of Alexandrium in the field. Two instruments will be transitioned for field use: the Surface Plasmon Instrumentation for the Rapid Identification of Toxins (SPIRIT) for use by state, university or industry scientists and the Portable Optical Sensing System for Environmental samples (POSSE) for use by volunteer monitors. Our modified detection instruments will undergo extensive field-testing on different sampling platforms prior to deployment. We will use feed-back from the Maine Department of Marine Resources (DMR) Biotoxin Monitoring Program and other end-users to help refine the instruments.
This project is led by Dr. Laurie Connell of the University of Maine, School of Marine Sciences, in partnership with the Maine Department of Marine Resources. It is part of the Monitoring and Event Response for Harmful Algal Blooms (MERHAB) program.
Benefits of our Work
This project will immediately apply and add value to the Maine DMR Biotoxin Monitoring Program by increasing their ability to focus limited resources to areas known as PSP “hot spots” or to identify toxin-free local areas caught up in broad brush closures. It will also serve as a demonstration model for other state and local agencies in implementing these detection methods. In addition, increasing restrictions on shellfish exports to the European Union (EU) creates a need for simple and rapid tests for other HAB species. Each of these new sampling methods can be expanded to detect other HAB species to meet EU requirements for imported shellfish.