Until further notice, certain portions of Maine’s coastline are closed to shellfish harvesting — and recently harvested clams and mussels are not to be consumed — because a naturally occurring algae is present in dangerously high levels. Maine’s Department of Marine Resources posted the so-called harvest recalls Friday after tests showed domoic acid at levels considered to be dangerous to humans. The department posted two notices for different areas. Together the notices ban the harvest of clams, mussels, European oysters, surf/hen clams, or carnivorous snails from the shores, flats and waters of several areas in Maine and its coastal waters. No illnesses have been reported, but the excessive levels of domoic acid can cause serious illness and death. Neither freezing nor cooking shellfish with these excessive levels removes the dangerous neurotoxin. Domoic acid can cause amnesic shellfish poisoning, or ASP. The symptoms include abdominal cramps, diarrhea, nausea and vomiting. Typically symptoms will appear within 24 hours after eating contaminated shellfish. High enough levels of the toxin can cause neurological problems including short-term memory loss, seizures, dizziness, motor weakness, headache, seizures, cardiac arrhythmia, coma and even death. A known phenomenon, West Coast shellfish fans are familiar with harvest bans because of domoic acid. The problem is not as common in the Northeast. For complete descriptions of the areas implicated by the harvest ban, please see:
- https://www1.maine.gov/dmr/shellfish-sanitation-management/closures/documents/64-A.pdf
- https://www1.maine.gov/dmr/shellfish-sanitation-management/closures/documents/64-B.pdf
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