Public health officials have closed Budd Inlet to recreational shellfishing after finding elevated levels of a marine biotoxin in shellfish harvested there.
The toxin is known as “diarrhetic shellfish poison,” and when consumed by humans can cause nausea, vomiting and, as the name would imply, diarrhea.
Like other marine toxins, it’s produced naturally by algae and then eaten by shellfish, according to the state Department of Health (DOH). Normally it only exists in small amounts, but a combination of sunlight, nutrient rich waters and warm temperatures can trigger more rapid algae reproduction, known as a “bloom.” The toxin doesn’t harm the shellfish, but can accumulate in their tissues at levels dangerous to humans. The shellfish tested contained the poison at a level of 23 micrograms per 100 grams, which exceeds the state’s safe limit of 16 micrograms per 100 grams. The closed area reaches from inner Budd Inlet to Boston Harbor and the tip of Cooper Point.
While the algae that produces diarrhetic shellfish poison has been around for a long time, only since 2011 have public health officials detected the toxin at unsafe levels, according to the DOH’s website.