Paralytic Shellfish Poisoning in Haines, Alaska
Paralytic shellfish poison (PSP) sampling efforts have been very successful in the commercial bivalve industry, but Alaska has a very limited program to monitor PSP for subsistence (AKA personal use or recreational use) harvest. PSP from subsistence harvested shellfish continue to cause illnesses and fatalities. In 2010 a fatality of a Haines, Alaska resident occurred with consumption of Dungeness crab (Metacarcinus magister) viscera, often termed “crab butter.” Following the fatal incident, a collaborative investigation was conducted on Dungeness crab and blue mussels (Mytilus trossulus). Results revealed dangerous PSP toxin levels in mussels and Dungeness crab.
Figure 1. Haines, Alaska study sites.
Tiayasanka Harbor is a small embayment with a total length of approximately 2.10 km and averaging 0.93 kms wide (Figure 1). Our 2010 study had investigated PSP in mussels and crab in both Taiyasanka Harbor and Letnikof Cove on the Chilkat Inlet to sample the locations where crab originated causing the PSP related death of the Haines man. The 2011 study began June 17. Results identified only low levels on the Chilkat (Figure 2) but Taiyasanka Harbor had high PSP levels both years.
The test results show two consecutive years (2010 and 2011) with very high levels of PSP in mussels in mid-June in Taiyasanka Harbor, levels that are many times higher that the FDA limit of 80 µg/100g and were high enough to sicken or kill people. The 2010 mussel samples contained concentrations as high as 2,793 µg/100g . The FDA limit for safe consumption is 80 µg/100g. The June 17, 2011 mussel sample exceeded 5,000 µg/100g, and decreased at each subsequent sampling event (see Figure 3). All 2011 Dungeness crab samples exceeded the FDA limit and peaked at 1,055 µg/100g on August 29, 2011 (see Figure 4). More information about PSP levels in Dungeness crab can be found at http://environmentalaska.us/psp-in-dungeness-crab.html.
Figure 1. Haines, Alaska study sites.
Tiayasanka Harbor is a small embayment with a total length of approximately 2.10 km and averaging 0.93 kms wide (Figure 1). Our 2010 study had investigated PSP in mussels and crab in both Taiyasanka Harbor and Letnikof Cove on the Chilkat Inlet to sample the locations where crab originated causing the PSP related death of the Haines man. The 2011 study began June 17. Results identified only low levels on the Chilkat (Figure 2) but Taiyasanka Harbor had high PSP levels both years.
The test results show two consecutive years (2010 and 2011) with very high levels of PSP in mussels in mid-June in Taiyasanka Harbor, levels that are many times higher that the FDA limit of 80 µg/100g and were high enough to sicken or kill people. The 2010 mussel samples contained concentrations as high as 2,793 µg/100g . The FDA limit for safe consumption is 80 µg/100g. The June 17, 2011 mussel sample exceeded 5,000 µg/100g, and decreased at each subsequent sampling event (see Figure 3). All 2011 Dungeness crab samples exceeded the FDA limit and peaked at 1,055 µg/100g on August 29, 2011 (see Figure 4). More information about PSP levels in Dungeness crab can be found at http://environmentalaska.us/psp-in-dungeness-crab.html.
Figure 2. Letnikof Cove mussels 2011.
Figure 3. Taiyasanka Harbor mussels 2011.
Figure 4. Taiyasanka Harbor Dungeness crab 2011.
Figure 5. PSP levels in mussels in Portage Cove.
Since the summer of 2012 the State of Alaska began the recreational shellfish pilot program in four Alaska communities. The Chilkoot Indian Association is responsible for the Haines collections in Portage Cove and Viking Cove (see Figure 1). Most of the PSP test results have been below the FDA limit of 80 µg/100g , but Portage Cove was at 165 µg/100g (Figure 5) and Viking Cove was at 120 µg/100g (Figure 6) exceeding safe PSP levels. The results show that the Haines area has had 4 consecutive years of PSP levels exceeding the FDA limit of 80 µg/100g.
Since the summer of 2012 the State of Alaska began the recreational shellfish pilot program in four Alaska communities. The Chilkoot Indian Association is responsible for the Haines collections in Portage Cove and Viking Cove (see Figure 1). Most of the PSP test results have been below the FDA limit of 80 µg/100g , but Portage Cove was at 165 µg/100g (Figure 5) and Viking Cove was at 120 µg/100g (Figure 6) exceeding safe PSP levels. The results show that the Haines area has had 4 consecutive years of PSP levels exceeding the FDA limit of 80 µg/100g.
Figure 6. PSP levels in mussels in Viking Cove.