NOAA scientists and their colleagues have discovered a biological marker in the blood of laboratory zebrafish and marine mammals that shows when they have been repeatedly exposed to low levels of domoic acid, which is potentially toxic at high levels.
While little is known about how low-level exposure to domoic acid affects marine animals or humans, high-level exposure through eating contaminated seafood can be toxic, and can lead to amnesic shellfish poisoning, with symptoms such as seizures, short-term memory loss and, in rare cases, death. Domoic acid is produced by particular species of marine algae and accumulates in marine animals such as clams and mussels.
The findings are reported in a study published in Public Library of Science journal (PLoS ONE), a peer-reviewed scientific journal. Up until now, the absence of a marker for such chronic exposure has been a barrier to accurately assessing possible effects to humans.
"This study paves the way for creating reliable blood tests for low-level domoic acid exposure, which could help scientists assess the effects of chronic exposure to both wildlife and people who eat seafood," said Kathi Lefebvre, Ph.D., a NOAA fisheries biologist and the lead author of the study. "We don't know yet if the same antibody response we found in the laboratory in zebrafish and naturally exposed California sea lions also occurs in humans. Our next step is to team up with human-health experts to answer that question."
In the NOAA study, scientists injected zebrafish two to four times a month over nine months with low levels of domoic acid in the laboratory. Although the zebrafish appeared healthy after 18 weeks, scientists detected an antibody response for domoic acid in blood samples. Scientists found a similar antibody response in blood samples taken from wild sea lions from central California, confirming that natural exposure to the toxin produces a similar response in marine mammals.
The researchers also found that long-term, low-level exposure to domoic acid does not build tolerance or resistance to it, but instead makes zebrafish more sensitive to the neurotoxin.
Domoic acid was first identified as a shellfish toxin in 1987, after more than 100 people were sickened from eating contaminated mussels harvested off the Canadian province of Prince Edward Island. In 1998, more than 400 California sea lions died on the U.S. west coast after consuming anchovies containing domoic acid.
Since the early 1990s, regular monitoring of shellfish has protected people from amnesic shellfish poisoning caused by high levels of domoic acid.
Lefebvre will continue to work with co-authors, John D. Hansen, Ph.D, an immunologist with the U.S. Geological Survey-Western Fisheries Research Center, Donald R. Smith, Ph.D., a toxicologist at the University of California at Santa Cruz, and David J. Marcinek, Ph.D., a physiologist at the University of Washington, to look for health consequences of low-level exposure to domoic acid using the antibody marker.
The study, "A Novel Antibody-Based Biomarker for Chronic Algal Toxin Exposure and Sub-Acute Neurotoxicity," was conducted by scientists with NOAA, the Marine Mammal Center, the U.S. Geological Survey-Western Fisheries Research Center, the University of Washington and the University of California Santa Cruz, and is available at http://dx.plos.org/10.1371/journal.pone.0036213 Funding for the study was provided by NOAA's Ecology and Oceanography of Harmful Algal Blooms program.
Brian Gorman | EurekAlert!
New malaria analysis method reveals disease severity in minutes
14.08.2017 | University of British Columbia
New type of blood cells work as indicators of autoimmunity
14.08.2017 | Instituto de Medicina Molecular
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences