Saxitoxin accumulates in which organisms most notably?

• A. Filter feeding organisms such as clams and oysters
• B. Crabs and lobsters
• C. Rice and corn
• D. Beef and lamb

Answer: (A)

Saxitoxin accumulates most notably in filter-feeding shellfish. These organisms, like clams and oysters, continually pump large volumes of seawater and concentrate dissolved toxins from harmful algal blooms, especially the dinoflagellates that produce saxitoxin. This buildup in their tissues means humans can develop paralytic shellfish poisoning if they eat contaminated shellfish. While crustaceans such as crabs and lobsters can encounter toxins, they are not the classic, most notable accumulators. Rice and corn are terrestrial plants and do not accumulate saxitoxin, and beef or lamb are not associated with this toxin either.