Toxins Produced by Marine Life

by: Michael Phife

This article is going to be a little bit different than my others. Instead of talking about a particular fish, I will be talking about the different toxins each type of fish can produce and their effects on humans. This, in my opinion, is very important to know in case any of you decide to get certain fish that emit toxins, or if any of you are divers out there and stumble upon one of these fish in the ocean. I will also go into detail about what these toxins do to the human body and how they should be treated in case you come into contact with them. I had to do a LOT of research from my biology books, textbooks, and various online research papers just to find some of this stuff… so I will be piecing together a list that will make this much simpler to read and be informed on.

*Please note that I am listing proven ways to treat these infections, but medical attention is ALWAYS to be sought under all circumstances.

 

Cholera

Cholera has been around for centuries, even being one of the earliest infections researched by doctors and scientists . It can be found in many sources, with the most dominant source being contaminated water. This disease attacks the small intestines, and affects roughly 5 million people a year and can even cause death in severe cases.

  • Species that carry it:
    • Copepods
copepod

Copepod

 

  • Symptoms:
    • Nausea
    • Vomiting
    • Diarrhea
    • Dehydration

 

  • Treatments:
    • Oral re-hydration therapy
    • Antibacterial medicine
    • Immediate medical help

 

Ciguatera

Ciguatera is a particular foodborne illness which is caused by eating contaminated fish. It is mostly found in reef fish, as those are the ones that tend to eat the original host of the illness; dinoflagellates. Dinoflagellates, or “dinos” are a type of marine plankton that has caused a very peculiar anomaly in the ocean called Red Tide.  This is an event where an algal bloom happens in parts of the ocean to make the water look red or brown from ashore. If you ever see this in the ocean, it is highly advised to stay away from the water because you can get very sick from even accidental consumption of the water. This also kills off fish due to the algae depleting the oxygen in the water. How do the fish affect us, though? Well, as mentioned above, ciguatera starts off in dinoflagellates which are first introduced to either coral or algae. Herbivorous fish then eat either of these species and become infected. Finally, carnivorous fish (much like the fish we eat from the ocean) will consume the herbivorous fish and it gets passed to us when ordering food. Usually divers and fishermen know what to look for to prevent contamination, but it is a very real possibility to still get sick from ciguatera if fish during processing go unchecked.

  • Species that carry it: 
    Red Tide

    Red Tide

    • Dinoflagellates
    • Reef fish
    • Barracuda
    • Eels

 

  • Symptoms:
    • Nausea
    • Vomiting
    • Diarrhea
    • Headaches
    • Muscle aches
    • Numbness in ligaments
    • Vertigo
    • Hallucinations
    • Paresthesia (tingling sensations)
    • Ataxia (lack of voluntary coordination of muscle movement)

 

  • Treatments:
    • Immediate medical help

 

Tetrodotoxin

Tetrodotoxin (TTX) is only found in one species of fish, and you will most likely never have to worry about it….unless you like eating the Japanese dish called fugu. For those of you unfamiliar with this food, it is essentially pufferfish that is cut in such a precise way to avoid all the toxins in their bodies to make it acceptable for consumption. Consumers of this food have said that fugu gives them a euphoric high after eating it, which is actually caused by a subtle form of neurotoxin pumping through their bodies to make them feel this way. The chefs that prepare this food traditionally had to cook it for themselves and eat it. If they survived, they were allowed to cook it for customers. However, if this dish is prepared incorrectly, you have anywhere from 20 minutes to 8 hours before death occurs. Tetrodotoxin is 1,200 times MORE potent than cyanide. Even if you do not die from this toxin right away, you will be in a state of near death for several days. It is also worth noting that you can be poisoned by this through injection or inhalation of the toxin.

  • Species that carry it:
    • Pufferfish
Puffer-Fish-Spikes

Porcupine Pufferfish

 

  • Symptoms:
    • Paralysis of diaphragm and other muscles
    • Loss of sensation
    • Loss of regular heart beat
    • Respiratory failure
    • Death

 

  • Treatments:
    • Immediate medical help

 

Ostracitoxin

Ostracitoxin is very similar to tetrodotoxin in the sense that it must be consumed or injected to affect humans. It is also only produced by one species of fish as well; boxfish. This toxin is very lethal to fish in about a 5 mile radius at only 10 parts per million of secreted toxin. Many people get these types of fish for aquariums. But the minute a boxfish becomes too stressed or endangered, it will release its toxins and wipe out your entire aquarium within minutes.

  • Species that carry it:
    • Boxfish
Yellow_Box_Fish.sized

Yellow Boxfish

 

  • Symptoms:
    • Severe muscle pains
    • Body weakness
    • Black discharge in urine
    • Respiratory failure
    • Death

 

  • Treatments:
    • Immediate medical help

 

Enterotoxin

Breaking away from a few of the more severe toxins is enterotoxin. This is a toxin that breaks down proteins in the intestines. It is almost never serious, and many reef hobbyists have encountered it before in their life times. The venom can usually be broken down by heat if someone is affected by it. Though in any case, it will make you re-think your decisions next time you play around on a reef bed while diving, or to take caution in your aquarium if you have the certain fish that produces it.

  • Species that carry it:
    • Rabbitfish
FoxfaceRabbitfish2

Foxface Rabbitfish

 

  • Symptoms:
    • Swelling
    • Stinging sensation
    • Abdominal cramps
    • Nausea
    • Diarrhea

 

  • Treatments:
    • Run affected area under 100F – 115F degree water

 

Nematocysts (Cnidocyte)

Nematocysts are an explosive cell found in the organs of Cnidaria species. It is usually found in their tentacles and helps to catch prey that falls victim by swimming through. This toxin works almost like firing a gun. The cell from the species is stored in a bulb capsule on its tentacle. Whenever something brushes against the area, it triggers the bulb to explode and eject itself into the victim. All of this is done within milliseconds, and is even hard to capture under a microscope. The most deadly species of this toxin is found in Box Jellyfish, which has caused numerous deaths in humans over the years.

  • Species that carry it:
    • Jellyfish
    • Anemones
    • Coral
jellyfish

Immortal Jellyfish

 

  • Symptoms:
    • Sticky sensation
    • Excruciating pain
    • Paralysis
    • Death

 

  • Treatments:
    • Remove tentacles from affected area
    • Hydrocortisone cream
    • Oral antihistamines
    • Immediate medical help

 

Neurotoxin

Last but not least, neurotoxins. This type of toxin is the most prevalent in all venomous creatures. It destroys nerve tissue and can even affect your neurological system if severe enough. Like many of these listed toxins, this is definitely not one you want to wait around for and see what happens. I cannot stress enough how you should seek medical help if affected by anything with neurotoxin, regardless of how small. It can have long term effects on the body if untreated. In fact, tetrodotoxin and ostracitoxin are sub-sects of neurotoxin. The toxin can last a minimum of 12 hours if affected by certain species, but fatal if affected by others.

  • Species that carry it:
    • Lionfish
    • Scorpionfish
    • Stonefish
    • Stingrays
    • Urchins
Common_lionfish_at_Shaab_El_Erg_reef_(landscape_crop)

Russell’s Lionfish

 

  • Symptoms:
    • Swelling
    • Bruising
    • Numbness
    • Nausea
    • Diarrhea
    • Abnormal heart rhythms
    • Headaches
    • Tremors
    • Respiratory failure
    • Seizures
    • Decreased blood pressure
    • Fainting
    • Paralysis
    • Death

 

  • Treatments:
    • Immediate medical help

 

 

References:

http://www.nhptv.org/wild/images/copepod.jpg

http://someinterestingfacts.net/wp-content/uploads/2013/01/Red-Tide-Australia.jpg

http://www.liverocknreef.com/liverock/images/products/large_10155_porcupine-fish-puffer.jpg

http://www.abovebelowphotos.com/albums/album05/Yellow_Box_Fish.sized.jpg

http://www.aquariumdomain.com/images/fish_marine/FoxfaceRabbitfish2.jpg

http://i.ytimg.com/vi/PFLSqvFO_Aw/maxresdefault.jpg

http://upload.wikimedia.org/wikipedia/commons/4/4c/Common_lionfish_at_Shaab_El_Erg_reef_%28landscape_crop%29.JPG