Over the past 30 years there has been a dramatic increase in the number of harmful algal blooms (HAB's) in coastal waters throughout the world. As a result, there are more toxic algal species, more algal toxins and more geographic areas impacted than ever before. When these toxic species proliferate, they may cause massive kills of fish and shellfish, wildlife mortality, human illness and death. One of these marine organisms, pseudo-nitzchia produces a neurotoxin, Domoic Acid (DA). Most of what we know about the human health effects of Domoic Acid has been derived from a single documented outbreak in Montreal Canada in 1987. Persons who ate mussels with high levels of DA suffered serious medical illnesses, including seizures and coma, and 3 people died. Survivors were left with a profound memory disorder, Amnesic Shellfish poisoning (ASP). Based upon animal models, regulatory levels of DA in shellfish were established. Within the past 17 years, DA levels have been close to or exceeded these safety levels at razor clam harvesting beaches on Native American Reservations in the Pacific NW. Recent data indicate that this population is currently at risk for significant, but preventable, neurobehavioral impairment (ASP) from razor clam consumption, with memory problems ranging from the low average to amnesic range. There appears to be a dose- response relationship between exposure and memory problems and the base rate of persons meeting the criteria for severe memory impairment, or ASP is 4.3%. The purpose of this 5 year longitudinal cohort study is to extend these findings to establish their clinical and public health significance. A prospective longitudinal cohort design of 735 Native Americans (ages 6 months to 75 yrs) from three Tribes, with nested case-control study of identified cases of "ASP" will be implemented. The health impacts of chronic, low level exposures to DA over time will be determined as well as the exposure and host factors associated with DA neurotoxicity. A new model of ASP, to include the potential for delayed or latent toxicity, recovery, and recurrence will be tested with state-of-the-art procedures for assessing human exposure (mobile technology) and behavioral neurotoxicity in infants, children, adults and geriatric groups. Findings will have a significant clinical and public health impact. The diagnosis and prognosis for ASP will be defined and established safety levels for exposure will be re-evaluated to insure they are protective of persons with long term, repeated exposure to DA.

Public Health Relevance

This study investigates the health impacts of Amnesic Shellfish Poisoning, a new environmental health problem caused by repeated exposure to the marine biotoxin, Domoic Acid. The clinical syndrome and risk factors for human illness in a group of NW Coastal Native Americans will be identified.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Research Project (R01)
Project #
5R01ES012459-09
Application #
8652455
Study Section
Neurological, Aging and Musculoskeletal Epidemiology (NAME)
Program Officer
Tyson, Frederick L
Project Start
2003-07-01
Project End
2016-02-28
Budget Start
2014-03-01
Budget End
2015-02-28
Support Year
9
Fiscal Year
2014
Total Cost
$823,899
Indirect Cost
$188,952
Name
University of Maryland Baltimore
Department
Neurology
Type
Schools of Medicine
DUNS #
188435911
City
Baltimore
State
MD
Country
United States
Zip Code
21201
Grattan, Lynn M; Roberts, Sparkle; Mahan Jr, William T et al. (2011) The early psychological impacts of the Deepwater Horizon oil spill on Florida and Alabama communities. Environ Health Perspect 119:838-43
Fialkowski, Marie K; McCrory, Megan A; Roberts, Sparkle M et al. (2010) Estimated nutrient intakes from food generally do not meet dietary reference intakes among adult members of Pacific Northwest tribal nations. J Nutr 140:992-8
Grant, Kimberly S; Burbacher, Thomas M; Faustman, Elaine M et al. (2010) Domoic acid: neurobehavioral consequences of exposure to a prevalent marine biotoxin. Neurotoxicol Teratol 32:132-41
Fialkowski, Marie K; McCrory, Megan A; Roberts, Sparkle M et al. (2010) Evaluation of dietary assessment tools used to assess the diet of adults participating in the Communities Advancing the Studies of Tribal Nations Across the Lifespan cohort. J Am Diet Assoc 110:65-73