SEPA

REGION 10 DIVE TEAM

www.epa.gov/region10/dive

. CPA Region 10 Dive Team

Survey of Shellfish for PSP and Domoic Acid in Puget Sound, 1994-1995

What: The EPA Region 10 Dive Team collected snails and clams for a limited survey of paralytic
shellfish poison (PSP) and domoic acid.

Why: To assess the PSP and domoic acid concentrations in predatory and other gastropods and bivalves
within the Puget Sound basin and potential human health risk.

Where/When: Agate Passage September 1994 & April 1995, Double Bluff September 1994, and
Mystery Bay October 1994, all in Puget Sound, WA.

How: Moon snails (Polinices lewissi), dogwinkle (Nucella lamellosa), an omnivorous snail (Searlesia
dim), Pacific oysters (Crassostera gigas), blue mussels (Mytihis edulis), and horse mussels (Modiolus
modiolus) were collected by hand from shallow subtidal areas. Butter clams (Saxidomus gigcmtus),
Pacific littleneck clams (Protothaca stamina), and soft-shell clams (Mya arenaria) were dug from the
intertidal area. All tissues were frozen. Analyses for PSP and domoic acid were performed by NMFS's
NW Fisheries Science Center.

Results: Analyses of tissue from two predatory gastropods, moon snails and dogwinkles, indicated a
presence of PSP, but domoic acid was not detected. Puget Sound predatory marine snails accumulate
PSP toxins to levels above the regulatory level (80 mg of STX equiv./lOO g). In 1994, moon snails in
Agate Passage averaged 145 mg of STX equiv./lOO g, while butter clams from the same area averaged
73 mg of STX equiv./lOO g.

More Details: Wekell. J.C.. R.M. Lorenzana. M. Hogan. and H. Barnett. 1996. Survey of paralytic
shellfish poison and domoic acid in Puget Sound predatory gastropods. J. Shellfish Res. 15(2):231-236.
(6 pp, 1 MB pdf)

Contact: Roseanne Lorenzana at lorenzana.roseanne@epa.gov
Return to EPA Region 10 Dive Team homepage.


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