How to Prevent Food Poisoning From Marine Toxins

Some fish, shellfish, and other small marine organisms contain poisons (toxins) that can make you sick if you eat them. Common types of marine toxin–related food poisoning include:

• Paralytic shellfish poisoning. This can happen when you eat fish or shellfish that live in places where there are overgrown algae blooms. Seafood from the coastal waters of the Pacific states and New England are most likely to cause this type of food poisoning.
• Scombroid fish poisoning. This can happen when you eat fish that have not been properly refrigerated or preserved. Scombroid fish poisoning can happen anywhere in the world.
• Ciguatera poisoning. This can happen when you eat fish or eel contaminated with toxins from a certain type of algae that grow on coral reefs. It usually happens in tropical and subtropical areas with warm water, but it can occur anywhere reef fish are eaten.
• Neurotoxic shellfish poisoning. This can happen from eating oysters, clams, and mussels from the coast of the southern United States and the Gulf of Mexico.

How can this condition affect me?

People often start feeling sick an hour or two after eating the fish or shellfish. Some types of marine toxin poisoning may cause flu-like symptoms, such as nausea, vomiting, diarrhea, and chills, that last only a day or two. Other types of marine toxin poisoning can cause serious harm to your brain and nervous system.

You may need treatment, depending on the type of poisoning or if you have certain health conditions, such as asthma. Treatment may include:

• Oral rehydration therapy (ORT) to replace fluids lost through vomiting and diarrhea.
• Medicines.
• Breathing support.

What can increase my risk?

You may be more likely to get food poisoning from marine toxins if you eat seafood that:

• Has been caught out of season.
• Has been caught in waters with algae blooms.
• Has not been refrigerated, preserved, or cooked properly.

What actions can I take to prevent food poisoning from marine toxins?

• Do not eat shellfish:
  • If you have a weakened defense (immune) system or low immunity.
  • Caught after an algae bloom.
  • Sold as bait.
• Do not eat reef fish or moray eel.
• Pay attention to signs or public warnings that say it is not safe to fish in certain areas.
• Do not eat the parts of fish where toxins concentrate. This includes the liver, intestines, eggs, and head.
• Remember that some marine toxins can survive cooking, canning, freezing, smoking, salting, and pickling.
• Keep fish below 38°F (3.3°C) at all times before cooking.
• Throw out fish that is old, has not been kept cold enough, or has spoiled or gone bad.
• Avoid eating shellfish while traveling abroad.

Where to find more information

Visit the Centers for Disease Control and Prevention website for more information on fish poisoning:

wwwnc.cdc.gov/travel/page/fish-poisoning-ciguatera-scombroid

Get help right away if you have signs of food poisoning:

• Flu-like symptoms such as nausea, vomiting, diarrhea, and chills.
• Rash.
• Headache.
• Sweating.
• Fatigue.
• Itchiness.
• Abdominal pain.
• Swelling of the mouth.
• Numbness, tingling, or itchiness in your face, tongue, fingers, or toes.
• Difficulty sensing heat or cold.
• Red or pink-looking (flushed) face.
• Racing heart.
• Trouble seeing or blurry vision.
• Trouble breathing or swallowing.
• Loss of coordination.
• Not being able to move (paralysis).

Summary

• You can get sick from eating fish or shellfish that contain poisons (toxins).
• To prevent this poisoning, do not eat shellfish if you have a weakened immune system or if the shellfish was caught after an algae bloom or was sold as bait. Also, do not eat reef fish, moray eel, or the parts of fish where toxins concentrate, including the liver, intestines, eggs, and head.
• Remember that some marine toxins can survive cooking, canning, freezing, smoking, salting, and pickling.