Common questions

Where does saxitoxin come from?

Where does saxitoxin come from?

Saxitoxin is produced by the dinoflagellates Gonyaulax, Alexandrium, Gymnodinium, and Pyrodinium. Similar to tetrodotoxin, saxitoxin binds to voltage-gated sodium channels within cell membranes, inhibiting membrane depolarization and blocking proliferation of action potentials.

Where is saxitoxin found in nature?

Saxitoxin and its derivatives, collectively referred to as paralytic shellfish toxins (PSTs), are unique among neurotoxins in that they are found in both marine and freshwater environments by organisms inhabiting two kingdoms of life.

How does saxitoxin cause paralysis?

Saxitoxin, like CTX and tetrodotoxin, causes paralysis by blocking sodium channels in nerve cell membranes. It is 50 times more potent than curare. Saxitoxin and other toxins that cause PSP are heat stable and are not destroyed by normal cooking procedures, marinating, or freezing.

How do I get saxitoxin?

Clinical description Exposure to saxitoxin most commonly occurs following ingestion of certain fish that contain it in their tissues. Ingestion of saxitoxin can cause numbness of the oral mucosa as quickly as 30 minutes after exposure.

How do you prevent saxitoxin?

To avoid Paralytic Shellfish Poisoning, members of the public are advised to observe the following:

  1. Buy shellfish from reliable and licensed seafood shops;
  2. Remove the viscera, gonads and roe before cooking;
  3. Eat a smaller amount of shellfish in any one meal and avoid consuming the cooking liquid;

How do you prevent tetrodotoxin?

Prevent others from eating until the source of tetrodotoxin exposure can be ascertained, in order to avoid more casualties. Do not induce vomiting (emesis). Administer supplemental oxygen and assist ventilation as needed. Seek medical attention immediately.

Can oysters paralyze you?

People can become ill from eating shellfish contaminated with Paralytic Shellfish Poison. This biotoxin affects the nervous system and paralyzes muscles, thus the term “paralytic” shellfish poison. High levels of Paralytic Shellfish Poison can cause severe illness and death.

Why is there no tetrodotoxin antidote?

Because the toxin is heat-stable, cooking does not destroy it. The toxin works by blocking sodium channels, in turn causing gastrointestinal, neurologic, and cardiac symptoms in patients with tetrodotoxin toxicity. There is currently no known antidote.

Are oysters toxic?

You can get seriously ill and even die from eating raw oysters contaminated with Vibrio vulnificus – a bacterium commonly found in waters where oysters are cultivated such as the Gulf of Mexico. Vibrio vulnificus is found in higher concentrations during the summer months as water becomes warmer.