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Chile Casts Off Toxic Tides

Fishing Boats

The poisonous microscopic algae shut down Chile´s billion-dollar fishing region and wreaked havoc on its costal community. (Photo credit: K. Hansen/IAEA) See photo gallery

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It has killed whales and comatosed seal lions. Caused pelicans to fall from the sky. For humans it brings lip-numbing pain and a choking death. The culprit - a single celled algae, whose toxins rank among the most potent natural poisons in the world.

Scientists call the poisonous algae Harmful Algal Bloom (HAB). But it goes by many other names - a "catastrophic ghost" of the sea, in the words of a local Chilean mayor. For fishermen the cell means almost certain unemployment and a hungrier family to feed.

Almost every coastal country around the world now confronts these deadly blooms. Shellfish filter and absorb the toxic algae, which if eaten, can be deadly. Scientists do not know exactly what causes HAB, or how to stop the outbreaks. The only thing they are sure of is that the attacks are intensifying.

The standard way to fight the ever-increasing blooms is to monitor coastal waters, and enforce blanket closures on the seafood industry if the dangerous algae are detected at unsafe levels. But it is a costly, hit and miss business. For decades scientists have used live mice - in a technique called the mouse bioassay - to test whether shellfish and seafood can be given the stamp of approval for export. The mice are jabbed with samples of shellfish, and if they survive for an hour, then the seafood is certified for export.

The method has animal-rights activists up in arms and leaves fishermen and health authorities frustrated at the time it takes to provide results, and that the present test lacks precision.

"There is a better method," says Dr. Benjamín Suárez-Isla, Director of Laboratory of Marine Toxins, University of Chile. A nuclear technique that offers a faster, cheaper more accurate means of detection, called a Receptor Binding Assay (RBA).

The IAEA has teamed up through its Technical Cooperation programme with Chile, the Philippines, New Zealand, Australia, China, Malaysia, Thailand, Pakistan, South Africa, Namibia, Angola, the United Kingdom, and the United States to work to change the controversial export standard.

Kerry Burns, Head of Chemistry Unit at the Agency´s Seibersdorf Laboratories, predicts it could be about five years before the RBA becomes the export standard. For fishing towns and communities, this better detection tool cannot come soon enough.

Next: The Fishermen of Chiloé »