Through the use of an automated, underwater cell analyzer developed at the Woods Hole Oceanographic Institution (WHOI), researchers and coastal managers were recently able to detect a bloom of harmful marine algae in the Gulf of Mexico and prevent human consumption of tainted shellfish.
Shellfish beds in parts of Texas have been closed for a month, though they are expected to re-open in the next few days.
Working with Rob Olson and Heidi Sosik—plankton biologists and instrument developers at WHOI—biological oceanographer Lisa Campbell of Texas A&M University used their “Imaging FlowCytobot” instrument to detect a substantial increase in the abundance of the algae Dinophysis acuminata in the waters of Port Aransas, Texas.
Dinophysis acuminata produces okadaic acid, a toxin that accumulates in shellfish tissues and can cause diarrhetic shellfish poisoning (DSP) in humans. DSP is not life-threatening, but symptoms include nausea, cramping, vomiting, and diarrhea. Cooking does not destroy the toxin in the shellfish.
The Imaging FlowCytobot, which is automated and submersible, counts microscopic plants in the water and photographs them. The images and data are relayed back to a shore-based laboratory, where specially developed software automatically classifies the plankton into taxonomic groups.
“It is very satisfying to find that a technology we developed as a research tool can be so effective for protecting human health,” said Olson, who has worked with Sosik for several years to prototype and modify flow cytometers, which are more typically used in many biological and medical laboratories.
“We designed the Imaging FlowCytobot for continuous monitoring of a wide range of plankton, and that turns out to be just what was needed to detect a harmful algal bloom that no one expected."
The discovery of the Dinophysis bloom came while the researchers were actually looking for something else. Campbell, Olson, Sosik, and colleagues deployed the instrument in the fall of 2007 at the University of Texas Marine Sciences Institute laboratory in the Mission Bay Aransas National Estuarine Research Reserve.
Their principal goal was to observe Karenia brevis, another toxic alga that blooms periodically in the Gulf and can lead to neurotoxic shellfish poisoning. The research team would like to observe the next K. brevis bloom before it happens; such blooms are most common and most extreme in the Gulf of Mexico in the late summer and fall.
The team is also working to catalog the types and relative abundances of marine plants in the area throughout the year.
In mid-February 2008, Campbell reviewed plankton images collected by the Imaging FlowCytobot and detected a substantial increase in the abundance of the dinoflagellate Dinophysis, which occurs naturally in ocean waters worldwide but not usually in harmful quantities.
“We have never before observed a bloom of Dinophysis acuminata at such levels in the Gulf of Mexico,” Campbell said.
After reporting the increase to fellow researchers in coastal Texas, Campbell and colleagues collected water samples to confirm that algal toxins were present in the water.
Other researchers collected oyster samples and sent them for toxin analysis at a U.S. Food and Drug Administration laboratory.
On March 8, the Texas Department of State Health Services closed Aransas, Corpus Christi, and Copano bays to shellfish harvesting and recalled Texas oysters, clams, and mussels that had been sold between March 1-7.
A week later, six other bays and estuaries along the coast were closed. As of April 11, most shellfishing areas had been re-opened, and the Aransas, Copano, and Corpus Christi were expected to re-open in a matter of days.
The bloom and subsequent warnings occurred just days before the Fulton Oysterfest, a major shellfish festival in the region. At last report, no shellfish-related human illnesses have been reported in Texas this spring.
“This is exactly what an early warning system should be,” said Campbell. “It should detect a bloom before people get sick. So often, we don’t figure out that there is a bloom until people are ill, which is too late. The Imaging FlowCytobot has proven itself effective for providing an early warning.”
“With time, we have come to see that the instrument has obvious practical uses,” added Sosik. “It now appears ready to make the transition from basic research tool to operative tool."
Funding for Campbell’s monitoring program and construction of the instrument was provided by the National Oceanic and Atmospheric Administration’s Cooperative Institute for Coastal and Estuarine Environmental Technology (CICEET).
Funding for instrument development and earlier prototypes of the FlowCytobot and the Imaging Flow Cytobot was provided by WHOI—through its Ocean Life Institute, Coastal Ocean Institute, Bigelow Chair, and Access to the Sea Fund—and by the National Science Foundation.
The Woods Hole Oceanographic Institution is a private, independent organization in Falmouth, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the oceans and their interaction with the Earth as a whole, and to communicate a basic understanding of the oceans' role in the changing global environment.
Media Relations | EurekAlert!
Scientists team up on study to save endangered African penguins
16.11.2017 | Florida Atlantic University
Climate change: Urban trees are growing faster worldwide
13.11.2017 | Technische Universität München
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
21.11.2017 | Physics and Astronomy
21.11.2017 | Materials Sciences
21.11.2017 | Health and Medicine