With toxic algal blooms which can increase the amount of harmful toxins in the shellfish that California residents consume ramping up in frequency and severity locally, scientists at USC have developed a new algae monitoring method in hopes of one day being able to predict when and where toxic "red tides" will occur.
"We have, what we fear, is a hotspot here for some types of toxic algal blooms," said David Caron, professor of biological sciences at the USC Dornsife College.
Caron's lab developed a quantitative assay, a procedure for measuring the quantity of specific types of algae in water samples taken from the coast. For the past four years, he used it in Redondo Beach's King Harbor to monitor the Alexandrium catenella algae, which produces saxitoxins, a group of neurotoxins that Caron called "one of the most toxic biologically produced chemicals in the world."
"Just like other species, microscopic species conduct warfare chemical warfare," Caron said. Saxitoxins are thought to help A. catenella keep from being eaten and to out-compete other, similar organisms.
Problems with A. catenella occur because the algae are food for clams, mussels, anchovies and sardines.
"That's when we get into trouble, when it gets into something we would eat," Caron said. In humans, the ingestion of saxitoxins causes paralytic shellfish poisoning.
Caron said that the California Department of Public Health does "a great job of keeping us safe" through water sampling, mussel sampling, and regular closures of shellfish harvesting during certain high-risk times of the year.
Over the past 10 years, however, a different type of algae that produces the neurotoxin domoic acid has been increasing on the west coast. Domoic acid produces amnesic shellfish poisoning in humans, and has been the cause of thousands of marine animal deaths off California during the past decade.
The first documented c
|Contact: Robert Perkins|
University of Southern California