Trend analysis of shellfish biotoxin closures in Washington State
Presentation Abstract
The marine biotoxin program at the Washington State Department of Health (WDOH) routinely collects, analyzes and records shellfish tissue samples for biotoxins in Washington since 1957. The WDOH has one of the largest sets of biotoxin data from shellfish tissue in the United States and analyzes over 3,000 samples each year. By the end of 2014, the dataset contained over 100,000 entries with information on toxin levels for Paralytic Shellfish Poison (PSP), Amnesic Shellfish Poison (ASP or domoic acid) and Diarrhetic Shellfish Poison (DSP) in different shellfish species and monitoring sites. The current monitoring program was established in 1990 with the mussel sentinel cage program. This analysis looks at how recreational biotoxin closures have changed from 1957 to 2014. Closure dates, frequency, and duration were determined for each county and waterbody using established regulatory limits and current management practices. Code/equations were developed in Microsoft Excel to establish closure and opening day(s) per year. Mussel data (Mytilus sp.) was used to determine biotoxin closures, except on the Pacific Coast where razor clam (Siliqua patula) was also included. Razor clams are the only molluscan shellfish harvested on Pacific Coast beaches. Biotoxins have impacted 90% of Washington waterbodies and have closed areas from a minimum of 14 days to over 200 days. 65% of waterbodies are only impacted by PSP and roughly 20% are impacted by a combination of two biotoxins. In waterbodies with dual closures, longer and overlapping closures have also been associated with new and emerging biotoxins such as DSP and ASP. Results also show that in about half of the coastal local health jurisdictions (LHJ's), PSP mussel closures are occurring about a month earlier in the year. These significant trends may lead to increased monitoring costs to ensure that Washington State shellfish is safe for human consumption.
Session Title
Changes in Ecosystem Function and Climate Revealed by Long-term Monitoring in the Salish Sea
Conference Track
Climate Change and Ocean Acidification
Conference Name
Salish Sea Ecosystem Conference (2016 : Vancouver, B.C.)
Document Type
Event
Location
2016SSEC
Type of Presentation
Oral
Genre/Form
presentations (communicative events)
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Marine toxins; Seafood poisoning--Washington (State)
Subjects – Names (LCNAF)
Washington (State). Department of Health
Geographic Coverage
Salish Sea (B.C. and Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
Trend analysis of shellfish biotoxin closures in Washington State
2016SSEC
The marine biotoxin program at the Washington State Department of Health (WDOH) routinely collects, analyzes and records shellfish tissue samples for biotoxins in Washington since 1957. The WDOH has one of the largest sets of biotoxin data from shellfish tissue in the United States and analyzes over 3,000 samples each year. By the end of 2014, the dataset contained over 100,000 entries with information on toxin levels for Paralytic Shellfish Poison (PSP), Amnesic Shellfish Poison (ASP or domoic acid) and Diarrhetic Shellfish Poison (DSP) in different shellfish species and monitoring sites. The current monitoring program was established in 1990 with the mussel sentinel cage program. This analysis looks at how recreational biotoxin closures have changed from 1957 to 2014. Closure dates, frequency, and duration were determined for each county and waterbody using established regulatory limits and current management practices. Code/equations were developed in Microsoft Excel to establish closure and opening day(s) per year. Mussel data (Mytilus sp.) was used to determine biotoxin closures, except on the Pacific Coast where razor clam (Siliqua patula) was also included. Razor clams are the only molluscan shellfish harvested on Pacific Coast beaches. Biotoxins have impacted 90% of Washington waterbodies and have closed areas from a minimum of 14 days to over 200 days. 65% of waterbodies are only impacted by PSP and roughly 20% are impacted by a combination of two biotoxins. In waterbodies with dual closures, longer and overlapping closures have also been associated with new and emerging biotoxins such as DSP and ASP. Results also show that in about half of the coastal local health jurisdictions (LHJ's), PSP mussel closures are occurring about a month earlier in the year. These significant trends may lead to increased monitoring costs to ensure that Washington State shellfish is safe for human consumption.
