CALIFORNIA DEPT.OF PUBLIC HEALTH ENVIRONMENTAL MANAGEMENT BRANCH Marine Biotoxin Monitoring Report October 2017 Technical Report No. 17-24 INTRODUCTION: This report provides a summary of biotoxin activity for the month of October, 2017. Toxin concentration ranges are provided for the paralytic shellfish poisoning (PSP) toxins and for domoic acid (DA). Estimates are also provided for the distribution and relative abundance of Alexandrium, the dinoflagellate that produces PSP toxins, and Pseudonitzschia, the diatom that produces domoic acid. Summary information is also provided for any quarantine or health advisory in effect during the reporting period. Please note the following conventions for the phy- toplankton and shellfish biotoxin distribution maps: (I) All estimates for phytoplankton relative abundance are qualitative, based on sampling (iv) Please refer to the appropriate figure key for an explanation of the symbols used on the maps. Northern California Summary: Paralytic Shellfish Poisoning Alexandrium was observed at several locations be- tween Marin and Monterey counties during October (Figure 1). The overall distribution of Alexandrium was similar to observations in September, although this dinoflagellate was currently observed at fewer sampling sites within this region. Alexandrium was common inside Bolinas Lagoon, with a significant number of cells observed on October 10. Cell densities were low at all other sites. PSP toxicity was detected in shellfish from a number of sampling sites between Sonoma and Monterey counties (Figure 2). High PSP concentrations were detected in mussels from Schoolhouse Beach (126 µg/100 g and 118 µg/100 g on October 16 and 22, respectively) and the Bodega Harbor sentinel mussel station (111 µg/100 g on October 20). The high lev- els of PSP toxins detected in rock scallop viscera from the Monterey Commercial Wharf in August (Continued on page 2) effort and percent composition; (ii) All toxin data Numerous chains of Alexandrium were observed in a sample from Bolinas Lagoon in Marin County. are for mussel samples, unless otherwise noted; (iii) All samples are assayed for PSP toxins; DA analyses are performed as needed (e.g., on the basis of detected blooms of the diatoms that produce DA);
Page 2 October 2017 Technical Report No. 17-24 (Continued from page 1) persisted through October, with 347 µg/100 g detected on October 10. Domoic Acid Pseudo-nitzschia was observed at sites in all coastal counties except Mendocino. (Figure 1). The distribution of this diatom was similar to observations in September, however it was observed at fewer sampling sites within this range during October. Pseudo -nitzschia remained abundant at several locations in Del Norte and Humboldt counties; this diatom was common offshore at Cordell Banks and at the Pacifica Pier (San Mateo County). The highest relative abundance of Pseudo-nitzschia was observed at Wilson Creek (October 17) for the second month in a row. A significant number of Pseudo-nitzschia was also observed inside Humboldt Bay near Indian Island on October 9. Low concentrations of domoic acid were detected at several locations in Del Norte and Humbolt counties in October (Figure 2). The highest concentration detected in mussels during October was 6.5 ppm in a sentinel mussel sample from the U.S. Coast Guard pier in outer Humboldt Bay (October 2). The CDPH Food and Drug Branch (FDB), in coordination with the (Continued on page 4) Figure 1. Toxic phytoplankton distribution in northern California.
Page 3 October 2017 Technical Report No. 17-24 Figure 2. Distribution of shellfish biotoxins in northern California.
Page 4 October 2017 (Continued from page 2) California Department of Fish and Wildlife (CDFW), submitted a number of Dungeness crab viscera samples for domoic acid analysis. Concentrations of domoic acid above the alert level were detected in crab samples from offshore of Del Norte, Humboldt, and northern Mendocino counties. Domoic acid concentrations below the alert level were detected in crab Technical Report No. 17-24 Figure 3. Toxic phytoplankton distribution in southern California. viscera samples from southern Mendocino County. Non-Toxic Species There was a transition from a diatomdominated assemblage in the northern counties to a mix of diatoms and dinoflagellates in Marin County, with dinoflagellates common to abundant between San Mateo and Monterey counties. Chaetoceros and Rhizosolenia were the most common diatoms, while the dinoflagellate Prorocentrum micans was common to abundant at Monterey Bay sampling sites. Akashiwo sanguineum was also common at the Monterey Commercial Wharf. (Continued on page 5) The Marine Biotoxin Monitoring and Control Program, managed by the California Department of Public Health, is a state-wide effort involving a consortium of volunteer participants. The shellfish sampling and analysis element of this program is intended to provide an early warning of shellfish toxicity by routinely assessing coastal resources for the presence of paralytic shellfish poisoning (PSP) toxins and domoic acid. The Phytoplankton Monitoring Program is a state-wide effort designed to detect toxin producing species of phytoplankton in ocean water before they impact the public. The phytoplankton monitoring and observation effort can provide an advanced warning of a potential toxic bloom, allowing us to focus sampling efforts in the affected area before California's valuable shellfish resources or the public s health is threatened. For Information on Volunteering: Email redtide@cdph.ca.gov or call 510-412-4635 For Recorded Biotoxin Information Call: (800) 553-4133
Page 5 October 2017 Technical Report No. 17-24 during October (Figure 4). Low concentrations of PSP toxins continued to be detected in sentinel mussels from outer Morro Bay (October 9), as well as in oyster samples from an inner bay aquaculture lease (October 2 and 9). A low concentration of these toxins was also detected in a mussel sample from Montaña de Oro on October 15. Figure 4. Distribution of shellfish biotoxins in southern California. Domoic Acid (Continued from page 4) Southern California Summary: PSP toxins were detected at several sites in San Luis Obispo County Pseudo-nitzschia was observed at sampling sites in each southern California County, except Los Angeles, in October (Figure 3). While the distribution of this diatom was similar to observations in September, there was a significant decrease in the relative abundance at sites in San Luis Obispo and Santa Barbara counties. Pseudo-nitzschia did remain common at Anacapa Island (October 25). Domoic acid was not detected in any shellfish samples analyzed in October (Figure 4). FDB and CDFW collected crab viscera samples from San Luis Obispo: of the six samples submitted, four had low levels of domoic acid. Samples of lobster viscera were also collected from the northern Channel Island chain. Of seven lobsters col- Paralytic Shellfish Poisoning: Alexandrium was only observed at one location in October (Figure 3). A small number of this dinoflagellate continued to be observed in midmorro Bay. The presence of this toxinproducing dinoflagellate has persisted in this region since June. The dinoflagellate Lingulodinium polyedrum remained common to abundant at sampling sites between San Luis Obispo and Orange counties. (Continued on page 6)
Page 6 October 2017 Technical Report No. 17-24 (Continued from page 5) lected near Santa Cruz Island, five were above the alert level, the highest concentration being 89 ppm. Of six lobsters collected near Anacapa Island, all were below the alert level and four were below the detection limit. Non-Toxic Species Dinoflagellates dominated the southern California coast, with Lingulodinium polyedrum continuing to be common to abundant between San Luis Obispo and Orange counties. See the Phytoplankton Gallery on page 8 for a spectacular photograph of bioluminescence in northern San Luis Obispo County, captured by Matt McKetchnie. Ceratium macroceros was abundant in a sample from Catalina Island, Prorocentrum micans was common at Bolsa Chica and Imperial Beach, and Ceratium furca and C. fusus were common at Imperial Beach and offshore of Mission Bay, respectively. Despite the dominance of dinoflagellates, the diatom Hemialus spp. was abundant offshore of Crystal Cove and common at the San Clemente Pier. QUARANTINES: The annual mussel quarantine was lifted on October 31 for all coastal counties except Sonoma. The CDFW closure of the razor clam fishery remains in effect due to the continued presence of dangerous levels of domoic acid in razor clams from beaches in Humboldt and Del Norte counties. Table 1. Program participants collecting phytoplankton samples. AGENCY # AGENCY # DEL NORTE COUNTY Yurok Tribe Environmental Group 1 CDPH Volunteer (Jim Hooper) 1 HUMBOLDT COUNTY Coast Seafood Company 5 Humboldt State University Marine Lab 1 MENDOCINO COUNTY CDPH Volunteer (Marie DeSantis) 2 SONOMA COUNTY CDPH Marine Biotoxin Program 2 MARIN COUNTY CDPH Volunteers 5 CDPH Marine Biotoxin Program 3 (Brent Anderson,George Clyde, Mike Chin) Hog Island Oyster Company 3 SAN FRANCISCO COUNTY CDPH Volunteer (Eugenia McNaughton) 2 Exploratorium 4 SAN MATEO COUNTY San Mateo County Environmental Health Dept. 6 The Marine Mammal Center 4 U.C. Santa Cruz 1 SANTA CRUZ COUNTY CDPH Volunteer (Jeff Palsgaard) 4 Santa Cruz County Environmental Health Dept. 4 U.C. Santa Cruz 4 MONTEREY COUNTY Monterey Abalone Company 3 The Otter Project 5 SAN LUIS OBISPO COUNTY CDPH Marine Biotoxin Program 1 CDPH Volunteer (Dan Hoskins) 1 Friends of the Sea Otter 2 Grassy Bay Oyster Company 6 Monterey Bay National Estuary Program 2 Monterey Bay National Marine Sanctuary 3 Tenera Environmental 2 SANTA BARBARA COUNTY U.C. Santa Barbara 4 VENTURA COUNTY CDPH Volunteer (Fred Burgess) 3 Channel Island High School 1 National Park Service 1 Ventura County Environmental Health Dept. 1 LOS ANGELES COUNTY Catalina Island Marine Institute 1 City of L.A. Environmental Monitoring Division 1 Los Angeles County Health Department 3 Los Angeles County Sanitation District 2 Los Angeles Water Keeper 1 Tole Mour 1 ORANGE COUNTY Amigos de Bolsa Chica 4 Back Bay Science Center 4 CDPH Volunteer (Truong Nguyen) 2 Orange County Health Care Agency 1 Crystal Cove Alliance 1 Ocean Institute 1 SAN DIEGO COUNTY Carlsbad Aquafarm, Inc. 1 Sea Camp/HABNet 1 Scripps Institute of Oceanography 4 Tijuana River National Estuary Research 3 U.S. Navy Marine Mammal Program 3 Wildcoast 2 On October 19 CDPH lifted the health advisory for scallops and clams in Los Angeles County. Recent testing confirmed that concentrations of domoic acid have remained at safe or undetectable levels. (Continued on page 7)
Page 7 October 2017 Technical Report No. 17-24 (Continued from page 6) Consumers of Washington clams, also known as butter clams (Saxidomus nuttalli), are cautioned to eat only the white meat. Washington clams can concentrate the PSP toxins in the viscera and in the dark parts of the siphon and can remain toxic for a long period of time. Persons taking scallops or clams, with the exception of razor clams, are advised to remove and discard the dark parts (i.e., the digestive organs or viscera). Razor clams (Siliqua patula) are an exception to this general guidance due to their ability to concentrate and retain domoic acid in the edible white meat as well as in the viscera. PSP toxins can produce a tingling around the mouth and fingertips within a few minutes to a few hours after eating toxic shellfish. These symptoms can be followed by disturbed balance, lack of muscular coordination, slurred speech and difficulty swallowing. In severe poisonings, complete muscular paralysis and death from asphyxiation can occur. Symptoms of domoic acid poisoning can occur within 30 minutes to 24 hours after eating toxic seafood. In mild cases, symptoms of exposure to this nerve toxin may include vomiting, diarrhea, abdominal cramps, headache and dizziness. These symptoms disappear completely within several days. In severe cases, the victim may experience excessive bronchial secretions, difficulty breathing, confusion, disorientation, cardiovascular instability, seizures, permanent loss of short-term memory, coma and death. Any person experiencing any of these symp- Table 2. Program participants collecting shellfish samples. COUNTY AGENCY # Del Norte Yurok Tribe Environmental Group 1 Humboldt Coast Seafood Company 10 Humboldt County Environmental Health Department 1 Mendocino Mendocino County Environmental Health Department 1 Sonoma CDPH Marine Biotoxin Program 2 CDPH Volunteer (John Morozumi) 2 Marin Cove Mussel Company 4 Hog Island Oyster Company 7 Marin Oyster Company 6 Pt. Reyes Oyster Company 2 Starbird Mariculture 1 CDPH Marine Biotoxin Program 2 San Francisco San Francisco Estuary Institute 1 San Mateo San Mateo County Environmental Health Department 3 Santa Cruz U.C. Santa Cruz 3 Monterey Monterey Abalone Company 4 San Luis Obispo Grassy Bar Oyster Company 9 Morro Bay Oyster Company 8 California Polytechnic State University 1 CDPH Volunteer (Stuart Helmintoller) 1 CDPH Marine Biotoxin Program 1 Santa Barbara Santa Barbara Mariculture Company 8 Santa Barbara Museum of Natural History Sea Center 1 U.C. Santa Barbara 4 Ventura Ventura County Environmental Health Department 1 Los Angeles Los Angeles County Health Department 3 Orange Orange County Health Care Agency 1 San Diego Carlsbad Aquafarm, Inc. 5 Scripps Institue of Oceanography 1 U.S. Navy Marine Mammal Program 3 toms should seek immediate medical care. Consumers are also advised that neither cooking or freezing eliminates domoic acid or the PSP toxins from the shellfish tissue. These toxins may also accumulate in seafood species such as crab, lobster, and small finfish like sardines and anchovies. Contact the Biotoxin Information Line at 1-800-553-4133 for a current update on marine biotoxin activity prior to gathering and consuming shellfish. If you are having difficulty accessing this document, please contact CDPH at 1-800-553-4133 to request this information in an alternate format.
Page 8 October 2017 Thalassionema Technical Report No. 17-24 Ditylum Chaetoceros A variety of diatoms, including Ditylum, Chaetoceros, and Thalassionema. The diatom Corethron was abundant in an offshore sample from Cordell Bank. Photo by Matt McKetchnie Bioluminescence at San Carpoforo, San Luis Obispo County. A phytoplankton sample was not taken, but the dinoflagellate Lingulodinium was abundant in the surrounding area. Photo courtesy of Matt McKetchnie.