Table of Contents
Where is saxitoxin found?
Saxitoxins are produced in freshwater and marine environments. In marine environments, they are often referred to as PSPs. Most human saxitoxin toxicoses have been associated with the ingestion of marine shellfish, which accumulate saxitoxins produced by marine dinoflagellates (Cusick and Sayler, 2013).
How is saxitoxin detected?
Although widely performed, saxitoxin testing is not terribly humane. In order to determine saxitoxin concentration, the most popular of three FDA-approved methods is to inject a mouse with a small amount of liquid containing an expected toxin, wait for the mouse to die, and record the time of its last breath.
How much saxitoxin is lethal?
The LD50 of saxitoxin, when ingested by humans, is 5.7 micrograms per kilogram. When delivered by injection, the LD50 of saxitoxin is 0.6 micrograms per kilogram. Symptoms of ASP begin from 15 minutes to 38 hours after ingestion, and the mortality rate is two percent.
How is saxitoxin treated?
There is no antidote for Paralytic Shellfish Poison. The only treatment for severe cases is the use of life support systems such as a mechanical respirator and oxygen until the toxin passes from the victim’s system. Survivors can have a full recovery.
What is the cause of 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:
- Buy shellfish from reliable and licensed seafood shops;
- Remove the viscera, gonads and roe before cooking;
- Eat a smaller amount of shellfish in any one meal and avoid consuming the cooking liquid;
Is there an antidote for saxitoxin?
Currently there are no antidotes to saxitoxin and treatment is supportive. While much is known about saxitoxin and its relationship to blooms of toxic dinoflagellates, reports of paralytic shellfish poisoning and descriptions of findings in its victims are infrequent in the medical literature.
What would happen to someone if they ingested saxitoxin?
In severe poisoning, illness typically progresses rapidly and may include gastrointestinal (nausea, vomiting) and neurological (cranial nerve dysfunction, a floating sensation, headache, muscle weakness, parasthesias and vertigo) signs and symptoms. Respiratory failure and death can occur from paralysis (1-5).
What causes saxitoxin?
What type of poisoning does saxitoxin cause?
Saxitoxin (STX) is a potent neurotoxin and the best-known paralytic shellfish toxin (PST). Ingestion of saxitoxin by humans, usually by consumption of shellfish contaminated by toxic algal blooms, is responsible for the illness known as paralytic shellfish poisoning (PSP).
How quickly does PSP progress?
PSP typically progresses to death in 5 to 7 years,1 with Richardson syndrome having the fastest rate of progression.
What are the neurologic effects of saxitoxins?
Typical neurologic effects induced by saxitoxins are nervousness, ataxia, convulsions, and paralysis. The paralysis of respiratory muscles can lead to the death of mice within a few minutes.
What happens if saxitoxin is detected in urine?
Respiratory failure and death can occur from paralysis (1-5). Biologic: A case in which saxitoxin in urine is detected, as determined by the CDC laboratory. (1-5) Environmental: Detection of saxitoxin in ingested compounds or seafood. (7-10)
What is saxitoxin?
Saxitoxin is denoted by red. Saxitoxin is a neurotoxin that acts as a selective, reversible, voltage-gated sodium channel blocker. One of the most potent known natural toxins, it acts on the voltage-gated sodium channels of neurons, preventing normal cellular function and leading to paralysis.
How quickly does saxitoxin cause numbness of the oral mucosa?
Ingestion of saxitoxin can cause numbness of the oral mucosa as quickly as 30 minutes after exposure.