Pseudo-nitzschia in the Chesapeake Bay
Pseudo-nitzschia is a diatom genus known for producing the neurotoxin, domoic acid. Domoic acid can cause amnesic shellfish poisoning (ASP) in humans and domoic acid poisoning (DAP) in marine mammals and birds. Both ASP and DAP are characterized by diarrhea, vomiting, siezures and impaired mental functions.
Pseudo-nitzschia can be found in both the Maryland and Virginia portions of the Chesapeake Bay, Delaware Bay and the Atlantic coast of Maryland, Virginia and Delaware. Domoic acid has been detected in water samples and cultures isolated from the Maryland and Virginia portions of the Chesapeake Bay and the Atlantic coast of Maryland.
There has been relatively little research into Pseudo-nitzschia species in the Chesapeake Bay. The genus is mentioned by Tango (2006), Marshall (1980, 1994) and Hasle (1965), who identified diatoms using light and electron microscopy. In reports by MD DNR, Pseudo-nitzschia species have traditionally been reported as either P. seriata or P. pungens and were generally assumed to be non-toxic. However, data now demonstrate that regional isolates do produce domoic acid.