Paralytic shell fish poisoning is caused by

Options

A. Astaxanthin
B. Saxitoxin
C. Aflatoxin
D. Peridinin

Answer

**Step-by-Step Solution:**

1. **Understanding Paralytic Shellfish Poisoning (PSP)**:
- Paralytic shellfish poisoning is a condition that occurs when humans consume shellfish that are contaminated with toxins.

2. **Identify the Source of Toxins**:
- The toxins responsible for this poisoning are primarily produced by microscopic algae, specifically during harmful algal blooms.

3. **Types of Shellfish Involved**:
- The shellfish involved in this poisoning are typically bivalve shellfish (like clams and mussels) and crustaceans (like crabs and lobsters), which are known as filter feeders.

4. **Mechanism of Toxin Accumulation**:
- These shellfish accumulate neurotoxins, particularly a toxin called saxitoxin, from the algae. They filter feed on the algae, leading to the concentration of these toxins in their bodies.

5. **Duration of Toxin Storage**:
- The shellfish can store these toxins for several weeks after the harmful algal bloom has passed, and in some cases, they can retain these toxins for up to two years.

6. **Conclusion**:
- Therefore, the cause of paralytic shellfish poisoning is the ingestion of shellfish contaminated with saxitoxin.

**Final Answer**: Paralytic shellfish poisoning is caused by **saxitoxin**.

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