Alexandrium tamarense facts for kids

Alexandrium tamarense is a tiny living thing found in the ocean. It is a type of dinoflagellate, which are like very small plants or algae. These tiny creatures are so small you need a microscope to see them!

This particular dinoflagellate is special because it can make a powerful natural chemical called saxitoxin. This chemical is a neurotoxin, meaning it can affect the nervous system of animals and humans. If people eat shellfish that have eaten a lot of Alexandrium tamarense, they can get sick with something called paralytic shellfish poisoning (PSP).

What is Alexandrium tamarense?

Alexandrium tamarense is a microscopic organism. It floats in the ocean, usually near the coast. It's part of the plankton, which are the tiny living things that drift in water. Plankton are a very important food source for many sea creatures.

This dinoflagellate has two whip-like tails called flagella. It uses these to move around in the water. It also has a hard outer covering, like a tiny suit of armor.

Tiny Ocean Dwellers: Dinoflagellates

Dinoflagellates are a large group of single-celled organisms. They live mostly in the ocean. Many of them can make their own food using sunlight, just like plants. They are a key part of the ocean's food web.

Some dinoflagellates can glow in the dark, making the ocean sparkle at night. Others, like Alexandrium tamarense, can produce toxins. These toxins can be harmful to other living things.

The Toxin It Makes: Saxitoxin

The chemical that Alexandrium tamarense produces is called saxitoxin. It is a very strong natural poison. When this dinoflagellate grows in large numbers, the amount of saxitoxin in the water can increase.

Shellfish like clams, mussels, and oysters eat these tiny organisms. They filter water to get their food. If they filter water with a lot of Alexandrium tamarense, the saxitoxin builds up in their bodies. The shellfish themselves are not harmed by the toxin. However, they become dangerous for humans and other animals to eat.

What is Paralytic Shellfish Poisoning (PSP)?

Paralytic Shellfish Poisoning, or PSP, is an illness. It happens when people eat shellfish that contain saxitoxin. The toxin affects the nervous system. This can lead to serious health problems.

Symptoms of PSP can include tingling lips and tongue. People might also feel numbness in their face and neck. In more severe cases, it can cause problems with breathing. It is very important to avoid eating shellfish from areas known to have these toxic dinoflagellates.

How to Stay Safe from PSP

• Always check local warnings about shellfish.
• Government agencies often monitor coastal waters.
• They will close areas to shellfish harvesting if toxins are found.
• Cooking shellfish does not destroy the saxitoxin.
• It's crucial to only eat shellfish from safe, approved sources.

Where Does It Live?

Alexandrium tamarense is found in many coastal waters around the world. It is often seen in the Mediterranean region. It also lives in other temperate and tropical waters. These areas provide the right conditions for it to grow.

It prefers waters that are not too cold or too hot. It also needs enough nutrients to thrive. Changes in ocean temperature and nutrient levels can affect how much it grows.

Why Are "Red Tides" Important?

Sometimes, Alexandrium tamarense and other dinoflagellates multiply very quickly. They can become so numerous that they color the water. This is often called a "red tide" or a harmful algal bloom (HAB). The water might look red, brown, or green.

These blooms are important because they can have a big impact on the ocean.

• They can harm fish and other marine life.
• They can make shellfish unsafe to eat.
• They can also affect tourism and fishing industries.

Scientists study these blooms to understand why they happen. They also work to predict them. This helps protect both people and the environment.

See Also

• Harmful algal bloom
• Saxitoxin
• Paralytic shellfish poisoning