Sea food biotoxin

Prof.Dr. Fhim ShaltoutProfessor of Meat Hygiene

Faculty of Veterinary MedicneBenha University, Egypt.

• Biotoxin a toxic substance produced by a living organism.

• In the marine environment, biotoxins are produced by several types of algae, such as diatoms and dinoflagellates, which can produce “harmful algal blooms” or “red tides.”

• Biotoxins become dangerous when they contaminate the food web, potentially causing injury or death to those who feed either directly or indirectly on them

• Marine toxin diseases are caused by a myriad of natural toxins produced by minute organisms called dinoflagellates and diatoms. These phytoplankton move up the food chain into shellfish and carnivorous fish where they concentrate in viscera, affecting those who consume them.

• these toxins are tasteless, odorless, and heat and acid stable

• The marine toxin diseases are categorized into 2 groups depending on their vectors: shellfish and fish.

• Shellfish harbor the toxins that produce paralytic shellfish poisoning (PSP), neurotoxic shellfish poisoning (NSP), diarrheic shellfish poisoning (DSP), and amnesic shellfish poisoning (ASP).

• Second groub, fish carry the toxins responsible for ciguatera and tetrodotoxin (fugu or pufferfish) poisoning

• The shellfish-associated diseases characterized by patches of discolored water and dead or dying fish.

Impacts of Harmful Algal Blooms

• Algal blooms occur in both saltwater and freshwater environments and cause harm through two primary mechanisms. 

• The first category of impacts is the production of toxins.  Toxins may kill fish or shellfish directly, or may cause one of several human illnesses following ingestion of contaminated seafood. 

• The second category of impacts is high biomass accumulation, which, in turn, leads to environmental damage or degradation.  These effects can include light attenuation, clogging of fish gills, or depletion of dissolved oxygen upon decay of the algal cells. 

The most significant public health problems caused by

harmful algae are• . ::• Amnesic Shellfish Poisoning (ASP)• Diarrhetic Shellfish Poisoning (DSP)• Neurotoxic Shellfish Poisoning (NSP)• Paralytic Shellfish Poisoning (PSP)• Ciguatera Fish Poisoning (CFP)• Gempylotoxin• Scombroid Toxin• Tetrodotoxin• Azaspiracid shellfish poisoning

Amnesic Shellfish Poisoning (ASP)

•causative organisms: Pseudo-nitzschia sp.

•toxin produced: Domoic Acid

Foods Associated with Illness

Mussels, clams, oysters, and scallops found in the coastal waters of the Pacific

Northwest and the east coast of Canada

ASP

•a life-threatening syndrome. It is characterized by both gastrointestinal and neurological disorders.

•symptoms include nausea, vomiting, abdominal cramps, and diarrhea.

• In severe cases, neurological symptoms include dizziness, headache, seizures, disorientation, short-term

memory loss, respiratory difficulty, and coma.• In the long term cause brain damage, and sometimes

even death, in elderly patients or patients with impaired kidney function Because there is no known antidote to

domoic acid

Ciguatera Fish Poisoning (CFP

•causative organisms: Gambierdiscus toxicus, Prorocentrum spp., Ostreopsis

spp., Coolia monotis, Thecadinium sp. and Amphidinium carterae

•toxins produced: Ciguatoxin/Maitotoxin

Foods Associated with Ciguatoxin

•Barracuda are commonly associated with ciguatoxin poisoning, but grouper, sea bass, red snapper, mullet, and a number of other fish that

live in oceans between latitudes 35° N and 35° S have also caused the disease.

• These fish are typically caught by sport fishermen on reefs in Hawaii, Guam, and other

South Pacific islands, the Virgin Islands, and Puerto Rico

Ciguatera

•It is characterized by gastrointestinal (diarrhea, abdominal cramps and vomiting), neurologic

(paresthesias, pain in the teeth, pain on urination, blurred vision, temperature reversal) and cardiovascular (arrhythmias, heart block)

signs•symptoms within a few hours of contaminated

fish ingestion. The pathneumonic symptom of Ciguatera intoxication is hot/cold temperature

reversal,. Prolonged itching

• Chronic ciguatera can also present as a psychiatric disorder of general malaise, depression, headaches, muscular aches, and peculiar feelings in extremities for several weeks

• Ciguatera can be sexually transmitted. With exposure of the mother, premature labor and spontaneous abortion have been reported, as well as effects on the fetus and newborn child through placental and breast milk transmission

•Ciguatoxin usually causes symptoms within a few minutes after eating contaminated fish, but occasionally symptoms may take up to 6 hours

to appear.• Symptoms usually clear in 1 to 4 weeks but can

last for years. Recovery time is variable, and may take weeks, months, or years. Rapid treatment (within 24 hours) with manitol is

reported to relieve some symptoms.

Diarrhetic Shellfish Poisoning (DSP

• causative organisms: Dinophysis sp.• toxin produced: Okadaic Acid

Foods Associated with Diarrhetic Shellfish Poisoning

• Diarrhetic shellfish poisoning is associated with mussels, oysters, and clams found in Gulf of Maine Puget Sound, WA Massachusetts Maine

DSP

• produces gastrointestinal symptoms, usually beginning within 30 min to a few hours after consumption of toxic shellfish

• The illness, which is not fatal, is characterized by incapacitating diarrhea, nausea, vomiting, abdominal cramps, and chills.

• Recovery occurs within three days, with or without medical treatment

Neurotoxic Shellfish Poisoning (NSP

•causative organism: Karenia brevis

•toxins produced: Brevetoxins

Foods Associated with Neurotoxic Shellfish Poisoning

•Neurotoxic shellfish poisoning is associated with mussels, oysters, and

clams found in the warmers waters of the western coast of Florida, the Gulf of

Mexico, and the Caribbean Sea

NSP

•produces an intoxication syndrome nearly identical to that of ciguatera.

• It is characterized, gastrointestinal and neurological symptoms

•In addition, formation of toxic aerosols by wave action can produce respiratory asthma-like symptoms. No deaths have been reported

and the syndrome is less severe than ciguatera, but nevertheless debilitating. Unlike ciguatera

•recovery is generally complete in a few days.• Symptom onset ranges from 15 minutes to 18

hours postingestion, and•The duration of toxicity ranges from 1-72 hours

(usually < 24 h) .•symptoms include gastroenteritis; rectal burning;

paresthesias of the face, trunk, and limbs; myalgias; ataxia; vertigo; and reversal of

hot/cold sensation.Other less common features include tremor, dysphagia, bradycardia,

decreased reflexes, and mydriasis.

•This syndrome presents much like ciguatera poisoning but without a paralytic

component, and it may last from several hours to a few days.

•The brevetoxins, unlike the other shellfish toxins, can become aerosolized by the surf

and produce an allergic response characterized by rhinorrhea, conjunctivitis,

bronchospasm, and cough

Paralytic Shellfish Poisoning (PSP

•causative organisms: Alexandrium spp.,Gymnodinium catenatum, Pyrodinium

bahamense

•toxins produced: Saxitoxins

Foods Associated with Paralytic Shellfish Poisoning

•Shellfish that have caused this disease include mussels, cockles, clams, scallops,

oysters, crabs, and lobsters found in colder waters such as those of the Pacific

and New England Coasts

PSP

•PSP, like ASP, is a life threatening syndrome.• Symptoms are purely neurological and their

onset is rapid.• Duration of effects is a few days in non-lethal

cases .•Symptoms generally begin with numbness or

tingling of the face, tongue, arms, and legs. This is followed by headache, dizziness, nausea,

vomiting, diarrhea, and muscular incoordination ..

•Patients sometimes describe a floating sensation.

• In cases of severe poisoning, muscle paralysis and respiratory failure occur and death may

occur in 2 to 25 hours .• .Symptoms usually begin from 15 minutes to 2

hours after eating contaminated shellfish but can take as long as 10 hours to appear .

•Symptoms are usually mild in healthy people, but in those with compromised health, the illness

can be severe or even fatal

•The most severe cases result in respiratory arrest within 24 hours of

consumption of the toxic shellfish.

• If the patient is not breathing or if a pulse is not detected, artificial respiration and

CPR may be needed as first aid .

•There is no antidote, supportive therapy is the rule and survivors recover fully

Scombroid poisoning

•Scombroid poisoning results from the eating of spoiled fish of the Scombroidea

or Scomberesocidae families ..

•The phenomenon occurs with the consumption of both fresh and canned

fish.

•Scombroid is caused by bacterial overgrowth associated with inadequate storage of fish that naturally contain high levels of histidine. These

surface bacteria decarboxylate histidine to produce high levels of histamine,

•Optimal conditions for poisoning occur when the fish is improperly stored in a range from 20° to

30°C .

Foods Associated with Illness

• Tuna, mackerel, mahimahi (dolphin fish), sardine, anchovy, herring, bluefish, amberjack, grouper, and marlin that have been improperly refrigerated or preserved have been implicated in scombroid poisoning.

• Fish contaminated with histamine may have a peppery, sharp, salty, or bubbly taste, but may also look, smell, and taste normal.

AZASPIRACID SHELLFISH POISONING (AZP)

•Azaspiracid is a previously unknown and structurally novel marine toxin found to be

responsible for an outbreak of diarrhetic food poisoning associated with consumption of

contaminated Irish shellfish in Europe in 1995•. These toxins accumulate in bivalve mollusks

that feed on toxic microalgae of the genus Protoperidinium sp

• azaspiracids can induce widespread organ damage in animals and because of that they are probably more dangerous than previously known

classes of shellfish toxins.

• First incidents of human intoxications by azaspiracid discovered in Ireland .

•  mechanism of action is largely unknown. It is a unique toxin group that targets the liver, lung, pancreas, thymus, spleen (T and B-lymphocytes) and digestive tract.

• The azaspiracid toxin group can cause severe poisoning in human consumers of mussels after being enriched in the shellfish tissues.

• Eating mussels is a special treat for many people, although it is not completely without danger.

• It has been known for a long time that consumption of mussels and other bivalve shellfish can cause poisoning in humans

• symptoms ranging from diarrhea, nausea, and vomiting to neurotoxicological effects,including paralysis and even death in extreme cases

Other natural toxins

• There are naturally occurring toxins in some species that do not involve marine algae

• 1-gempylotoxin

• 2-Tetrodotoxin

• 3-Tetramine

gempylotoxin.

•Nature of Disease •An outbreak of gastrointestinal illness occurred

amongst attendees of a conference lunch in the Hunter area, New South Wales,

•The median incubation period was 2.5 hours.• The most common symptoms were; diarrhoea is

oily,abdominal cramps ,nausea ,headache ,and vomiting

Associated Foods

•Symptoms are associated with the ingestion of Escolar (Lepidocybium flavobrunneum) or Oilfish (Ruvettus pretiosus). Other species (including

Butterfish, Rudderfish, Cod, and Taiwanese Seabass

Tetrodotoxin

•Puffer fish, or fugu, may contain tetrodotoxin. Poisonings from tetrodotoxin have usually been

associated with the consumption of puffer fish from waters of the Indo-Pacific ocean regions.

•Symptoms of poisoning usually begin within 10 minutes of consuming puffer fish .

•The victim first experiences numbness and tingling of the mouth, weakness, paralysis,

decreased blood pressure, and weakened pulse. Death can occur within 30 minutes

Tetramine

• Tetramine is a toxin that is found in the salivary glands of Neptunia spp., a type of whelk.

• controlled by removing the glands

Finding

• Fish is one of the most food insecure, between complaints of mad cow and avian flu, fled, many to the sea

• it seems not as much security you think a lot; have dropped more than 12 species of fish toxic to the markets of Egypt and the Arab, a part of more than 100 species of fish poison in the world,

• because the majority of the citizens and even traders fish can not differentiate between species of toxic and other have emerged another class of traders pretend consumers that the fish of the finest species, and sell them to toxins at some cheap and others are exaggerated

• In the source of the fish; where they are sold at the small traders and street vendors, they start selling these alien species, such as: rabbat fish or basa fish " with a red meat that have been shown to contain some toxic substances,

• It eliminates the effect if the cook fish in the oil in a frying, due to high oil temperature. It may not lose the fish effect by grilling so have some harmful effects on human health, such as nausea, vomiting, and there are others who the disposal of fish offal, especially liver

• difficult to distinguish these fish just by looking; because some traders get these fish that are caught from the Red Sea, and the cut it and change its features and then soaked in vinegar and salt to change the smell unpleasant; and therefore difficult to distinguish them from others; where the leaves never form

• confirmed by "Chef Zakaria" chef one of the five-star hotels in Cairo, who happens to buy large quantities of fish to the hotel, he said: The distinction of the meat of these fish is difficult just by looking, but it can be seen during the cooking and cooking, for example in fish fillet notes that its flesh is not coherent, and well below the size of the fish during frying or grilling these fish

Rabbat fish

Cairo - Scientists have warned fish from eating fish "rabbit" because they contain a deadly poison with food

poisoning in humans and ultimately lead to death,

Is concentrated in the liver of the fish and its head has two effects, first targeting the gastrointestinal tract and

cause food poisoning, diarrhea and a sense of visual problems in the eye.

He explained that the second effect is the effect of the toxic fish where it enters a deadly poison to the nervous

system and afflicts paralyzed and then death occurs .

•warning came after the rabbit caused a fish poison in the death of a policeman in the city of Suez "140 kilometers

east of Cairo," and wounded four of his colleagues at the port after eating a fish meal of this kind.

Another person died in the town of Ras Gharib, the Red Sea province also wounded 14 people in the governorate

of South Sinai after eating toxic fish.

And returns the first cases of death from eating the fish to the year 2007, when seven people died among 280

people were poisoned. "DPA

•some fishermen resort to the use of dynamite and pesticides the D. DT a means of hunting

prohibited and forbidden to get on the outcome of the largest in the fishing,

•This leads to the poisoning of fish, and can detect those types of fish by smell gills fish, and

that have a pungent odor during frying it is possible that emits odors jazz or pesticide

The ignorance of consumers

Methods of Analyses

•ELISA

•HPLC

Public Health Significance

•There is no antidote for biotoxin poisoning.• The victim must wait for the toxins to naturally

flush from their body•Life support systems such as respirators and

oxygen are used in extreme cases to keep the victim alive and stable.

•Cooking does not destroy biotoxins. Cooking will kill the toxin-producing algae, but the toxin itself

is not affected by cooking and remains in the shellfish tissue

•Mussels accumulate toxins more quickly than other types of shellfish and .

•Their proximity to shallow beaches and fresh water sources (and thus potential pollution) are

additional reasons to be especially aware of surrounding conditions when harvesting this

species.•Varnish clams and butter clams store toxins

longer than other species, and can remain toxic for more than a year after a bloom subsides. For this reason an area can be closed to varnish and

butter clam harvest but open for other species

Prevention

•It is important to notify public health departments about even one person with marine toxin poisoning.

Investigators can then try to determine if a specific restaurant, oyster bed, or fishing area has a problem.

This prevents other illnesses .•In any food poisoning occurrence, consumers should

note foods eaten and freeze any uneaten portions in case they need to be tested.

• In Hawaii, a commercial test has been developed to allow persons to test sport-caught fish for ciguatoxins .

Guidelines for safe seafood consumption

•Although anyone eating fish or shellfish containing toxin

•persons with weakened immune systems or liver problems should not eat raw seafood because of

their higher risk of infection .•Seafood should be kept on ice or refrigerated at

less than 38° Fahrenheit to prevent spoilage

Avoiding marine toxin poisoning

•Fresh tuna, mackerel, grouper, and mahi mahi should be refrigerated to prevent development of

histamine.• Cooking spoiled or toxic seafood will not make it

safe to eat. These toxins are not destroyed by cooking .

•Barracuda should not be eaten, especially not those from the Caribbean .

•Local health officials should be consulted before shellfish are collected.

•Health Department advisories about algal blooms, dinoflagellate growth or "redtide"

conditions may be posted at fishing supply stores .

•Finfish or shellfish sold as bait should not be eaten.

Diagnosis

• •Diagnosis of marine toxin poisoning is generally based

on symptoms and a history of recently eating a particular kind of seafood. Laboratory testing for the specific toxin in patient samples is generally not necessary because

this requires special techniques and equipment available in only specialized laboratories. If leftover fish or shellfish are available, they can be tested for the presence of the

toxin more easily. Identification of the specific toxin is not usually necessary for treating patients because there is

no specific treatment .• .

Treatment

•There are no specific treatments for marine toxin poisoning. Treatment generally consists of

managing complications and being supportive until the illness passes..

•To prevent dehydration, take frequent sips of a rehydration drink (such as Lytren, Pedialyte, or

Rehydralyte) ..•You can also use a sports drink, such as

Gatorade. Soda and fruit juices have too much sugar and not enough of the important

electrolytes that are lost during diarrhea, and they should not be used to rehydrate .

•Other than supportive care there are few specific treatments for ciguatera poisoning, paralytic

shellfish poisoning, neurotoxic shellfish poisoning, or amnesic shellfish poisoning.

Antihistamines and epinephrine, treating the symptoms of scombrotoxic fish poisoning .

•Intravenous mannitol has been suggested for the treatment of severe ciguatera poisoning

Long-term consequences

•Ciguatera poisoning has resulted in some neurologic problems that can last for weeks, and

in rare cases, even years.• Symptoms have sometimes returned after

eating contaminated fish a second time .•Shellfish poisoning has resulted in long-term

problems with short-term memory in some people.

• Long-term consequences have not been associated with paralytic shellfish poisoning,

neurotoxic shellfish poisoning, and scombrotoxic fish poisoning .

Public Health Government

•Some health departments test shellfish harvested within their jurisdiction to monitor the level of dinoflagellate toxins and asses the risk for contamination. Based on the results of such

testing, recreational and commercial seafood harvesting may be prohibited locally during periods of risk. State and federal regulatory

agencies monitor reported cases of marine toxin poisoning, and health departments investigate

possible outbreaks and devise control measures