Frequently asked questions (F.A.Q.´s)
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- What is Red Tide?
- What does microalgae mean?
- Is Vibrio parahaemolyticus (Vibrio parahaemolyticus) Red Tide?
- Can seafood have both Vibrio parahaemolyticus and Red Tide?
- What are the differences between Vibrio parahaemolyticus and Red Tide?
- Why is it called Red Tide?
- Is the red tide really red?
- What is the actual name for Red Tides?
- What does bloom mean, and why was that term chosen?
- What produces a red tide?
- When is a red tide formed?
- Why does this phenomenon affect me?
- Can something happen to me if I drink seawater in a FAN?
- Are there any external signs in mollusks?
- Can I eat seafood that do not appear in the warnings from the Environmental Department of the Health Seremi?
- Will cooking these shellfish remove the toxin?
- What can I eat safely?
- Why is it so important for Chile to study Red Tides or FAN?
- How many poisonous toxins are there?
- What are the symptoms caused by these poisons?
- Are there antidotes for these toxins?
- What I can do to live without fear of the Red Tide?
- What is Red Tide?
Red Tides are a very large increase in the population of algae and can produce harmful disorders in humans by eating shellfish that have fed on these algae, which can produce poisonous toxins. It is not a virus, bacteria or fungus, nor is it an infection.
- What does microalgae mean?
Microalgae means microscopic algae, it is an algae that cannot be seen with the naked eye, a special instrument with high magnification is needed.
- Is Vibrio parahaemolyticus (Vibrio parahaemolyticus) Red Tide?
No. They are different things. Vibrio parahaemolyticus is a bacteria that lives in the sea, and when conditions are favorable it increases its population, infecting shellfish. It is similar to the cholera bacteria and causes acute gastroenteritis, ie. severe diarrhea. It is not a Harmful Algal Bloom or FAN.
- Can seafood have both Vibrio parahaemolyticus and Red Tide?
Yes. You may find both situations, so it is necessary to analyze shellfish extraction of each item before put in the market.
- What are the differences between Vibrio parahaemolyticus and Red Tide?
Vibrio parahaemolyticus is a bacterium, Red Tide is a product of phytoplankton; vibrio is killed when seafood is boiled and cooked, Red Tide cannot be removed from seafood. Vibrio produces violent diarrhea, Red Tide can result from diarrhea to life-threatening paralysis. If the cold chain is broken in shellfish, vibrio may appear in them; Red Tide is not dependent on external factors, if the analysis approves its use than it is safe to eat seafood. Red tide is not spread by contact, vibrio itself can contaminate any food touched by the seafood.
- Why is it called Red Tide?
Its name comes from the fact that years ago the phenomena was only known for the color changes in the water, and the most noticeable color change was of a reddish tone and so the name “Red Tide” became popular. There are red tides that produce other colors such as green, brown, yellow, orange, etc. The majority of Red Tides do not produce discoloration of the water. Of the thousands of types of red tides, only a small percentage are deleterious (harmful) to humans (10% of the total).
- Are Red Tides red?
Not necessarily, they can produce different color variations and even no color at all.
- What is the actual name for Red Tides?
It’s called Harmful Algal Bloom, abbreviated FAN.
- What does bloom mean, and why was that term chosen?
It is called bloom because Red Tides are rapidly formed and recalls the appearance of flowers in a field on springtime.
- What produces a red tide?
Red Tides are formed when microalgae receive a large amount of food in a short period of time. This phenomenon can be produced by natural causes or by the side effects of man´s activity.
- When is a red tide formed?
Since red tides need sunlight and great amount of nutrients, the best time for this bloom is between spring and summer, however it has been recorded that they can also be formed in autumn due to the mixtures of water and upwelling.
- Why does this phenomenon affect me?
Eating contaminated shellfish can cause you to suffer health problems that can lead to death. In addition, the Red Tide affects local and national markets, it can increase the value of seafood and thus affect the economy of many local people.
- Can something happen to me if I drink seawater with FAN?
No, microalgaes are very small, swallowing seawater will not affect your system. You would have to swallow thousands of liters for it to affect you.
- Are there any external signs in mollusks?
As for mollusks, they are not altered in color, taste, odor, or appearance, they do not die and there is no visible sign to identify which ones are infected and which are not. Only a specific analysis done by the Health Seremi Environmental Laboratory can detect the presence of toxins.
- Can I eat seafood that does not appear in SEREMI´s warnings?
No, it is not recommended. Seremis Healths laboratory warning alerts, are based on the country’s main commercial resources, but this does not mean that other species aren´t infected. For the region of Magallanes the following resources cannot be eaten without previously being analyzed: clams, mussels, oysters, picuyo snail, piquilhue snail, trophon snail, loco, picoroco and piure. Lapa and Maucho although not listed as dangerous animals, there have been records of VPM toxicity in them.
- Will cooking these shellfish remove the toxin?
No, cooking will not remove the toxin, nor the addition of lemon, vinegar or alcohol. These substances favor the absorption of the toxin. It is important to note that poisoning is caused by eating shellfish and not by touching or handling them, even when they contain a high level of toxin.
- What can I eat safely?
Surely you can eat any seafood that has been previously analyzed. You should always demand the certificate of analysis that the SS legally establishes for seafood sale and distribution.
- Why is it so important for Chile to study Red Tides or FAN?
It is a fact that these situations affect the health of the population and local economy. It is an important fact that we must know to safeguard the welfare of all Chileans and those visiting Chile.
- How many poisonous toxins are there?
There are several, but some are not in our waters yet. The most important in Chile are Amnesic Shellfish Poison (VAM), the Diarrheal Shellfish Poison (VDM) and Paralytic Shellfish Poison (PSP).
- What are the symptoms caused by these poisons?
All mentioned poisons can cause nausea, dizziness and headache as initial symptoms of poisoning, however, as the name implies, in case of significant ingestion it can cause:
VAM: Permanent Amnesia of short-term memory and possible death.
VDM: Severe diarrhea and dehydration associated effects. Presumably causes cancers of the digestive system.
VPM: muscle paralysis in varying degrees and even death by asphyxiation (apnea)
- Are there antidotes for these toxins?
To date, no effective antidotes against red tide are known. There are hospitalization techniques that keep the person alive after the poisoning, until the body recovers from the toxins effects.
- What I can do to live without fear of the Red Tide?
Be responsible, do not eat seafood without approval fromt the government.
The Red Tide is like the famous Russian roulette… you will NEVER know if the danger is in your hands at the time, until it becomes too late. Prevention is the key to living happier.