Parts of Maine’s coastline are being closed by the State of Maine Department of Marine Resources to certain types of shellfish harvesting because tests showed the sea creatures may contain domoic acid toxin at dangerous levels. Two notices have been posted on the Maine web site: one for Area No. 64-A and the other for Area No. 64-B. In addition to this closure, clams and mussels recently harvested from those areas should not be eaten.
Domoic acid is a biotoxin produced by a plankton, or naturally occurring algae, called diatoms. The toxin accumulates in shellfish flesh but does not hurt those animals. Excessive levels of this toxin can cause serious illness and even death in humans. The illness caused by this toxin is called amnesic shellfish poisoning (ASP).
The notice for 64-A closes an area near Cape Jellison, Resolution Island, Compass Island, Bald Island, Barred Island, and Saddleback Ledge. No mussels, European oysters, or surf/hen clams can be harvested from those areas. And it is unlawful to harvest any clams from the shores of the areas near Point of Maine, Otter Point, Bar Harbor, Sheep Porcupine Island, Burnt Porcupine Island, and Bunkers Cove.
The notice for 64-B closes the entire region from Point of Maine to the US/Canadian border for clam harvest. The notice also eliminates Exception Area 64-B-02. It is unlawful to dig, take, or possess any mussels or carnivorous snails from the shores, flats, and waters of those areas. For details on the exact areas of closure, please read the notices linked above.
The symptoms of domoic acid poisoning or ASP include short-term memory loss, dizziness, seizures, headache, heart arrhythmia, and muscle weakness. These symptoms usually appear within 24 hours after exposure to the toxin. If you ate any clams or other shellfish harvested in Maine and have experienced these symptoms, please see your doctor immediately. Trouble breathing, permanent loss of short-term memory, and coma can occur in patients with severe cases.