By Oliver Lazenby
The Washington State Department of Health (DOH) in June closed all Whatcom County beaches north of Sandy Point including Point Roberts, Blaine and Birch Bay for recreational harvest of molluscan shellfish last week. During routine testing, the agency found unsafe levels of a dangerous biotoxin that can cause paralytic shellfish poisoning (PSP), which is produced by some species of algae.
The toxin affects the nervous system and can paralyze muscles, hence the name. The closure is specific to molluscan shellfish, including clams, mussels, oysters and scallops. The toxin doesn’t accumulate in crab meat, but it can in “crab butter” and internal organs, and those should be discarded, according to press release from the DOH.
It’s impossible to tell if shellfish contain PSP without a laboratory test, and cooking does not make affected shellfish safe to eat.
The recreational closure doesn’t affect commercial harvesters, because the state has a separate process for testing commercial shellfish.
The county and state will continue testing for toxins weekly, and will notify the public when beaches reopen, said Melissa Morin, communications specialist with the Whatcom County health department. The algal blooms that produce the toxin happen when water conditions are favorable, but the exact conditions that cause the blooms are unknown.
“Typically the levels of the toxin fluctuate all summer, and there are just so many factors that go into it,” Morin said. “Usually this happens every summer.”
According to Tom Kunesh, environmental health supervisor for the Whatcom County Health Department, toxin levels in Point Roberts and Blaine’s Drayton Harbor nearly doubled in one week. Levels in Birch Bay mussels were almost seven times higher than the week before; at 557 micrograms, Birch Bay mussels are toxic enough to cause symptoms.
Toxins tend to accumulate sooner in mussels than in other mollusks; in effect, they are the underwater canary in a coal mine alerting health authorities to potentially dangerous toxin levels.
Before harvesting, always check the biotoxin hotline (800/562-5632) or check the biotoxin map online at bit.ly/2rvPbwd.
Shellfish harvesting is closed in all waters in the lower mainland B.C.