Domoic Acid

What does this compound have in common with Alfred Hitchcock?

Domoic Acid is thought to be the toxin that caused strange behavior in birds in Capitola, CA in 1961.  Alfred Hitchcock directed the film "The Birds" in 1963 after visiting the area and reading newspaper accounts of the events.  He also based the film on a short story by Daphne du Maurier in which the birds attack people in Britain. 

Domoic Acid is a structural analogue of glutamic acid  produced by a series of related diatoms including Pseudonitzschia australias, and N. pungens.  The clinical poisoning is referred to as Amnestic Shellfish Poisoning (ASP).  The toxin is produced in large quantities during an algae bloom and is consumed by fish and shellfish.  Domoic Acid seems to have no effect on the shellfish but if eaten by birds, man and other mammals produces systemic poisoning.  The blooms occur virtually all over the world and in the US occur on both coasts.  The blooms and the associated toxin are monitored closely by state and federal wildlife and agricultural departments. 

Many poisonings have been reported in public press over the past 40 years with the latest reports being this year.

The only human cases that I found occurred in Canada.  At the end of November 1987, 153 cases of acute intoxication after ingestion of toxic mussels were reported associated with blooms of the marine diatom Pseudonitschia pungens. The International Bird Rescue Research Center (IBRRC) tracks domoic acid outbreaks mostly in southern CA and  videos and stories about poisonings can be found online.  These outbreaks threaten in addition to the birds other animals that feed on the algae such as dolphins, sea lions, and particularly important to humans, shellfish.  An area where domoic acid is important is in Washington State where razor clams are a popular delicacy.  The WA State Department of Health monitors the domoic acid concentration in the clam and closes clam collections when levels are high.  See their web site for graphs of historical and current levels of domoic acid in various locations.

For additional information–e article in Fall 2007 Therapeutics and Toxins Newsletter.


 

Pseudo-nitzschia