Enhancing Shellfish Safety in Alaska through Monitoring of Harmful Algae and Their Toxins

Harmful algal blooms cause serious problems to public health and the economic viability of shellfish industries in Alaska. The most common phycotoxins in this region are saxitoxin and its congeners, collectively referred to as paralytic shellfish toxins, the causative agents of paralytic shellfish poisoning (PSP) in humans. The illness of 26 and death of 2 people in southeast Alaska as a result of PSP in 2010 through 2012 illustrates the need for change in the way paralytic shellfish toxins are monitored and managed in Alaska. The implementation of a scientific monitoring partnership, the Alaska Harmful Algal Bloom monitoring network, designed to provide an early warning of harmful algal blooms—in particular, those that cause PSP—is described. The program includes a tiered sampling approach, and weekly microscopic observation of seawater samples for the presence of the causative toxic dinoflagellate Alexandrium, followed by rapid toxin testing using a high-throughput antibody-based test as a complement to the standard regulatory testing performed by managers at the Alaska Department of Environmental Conservation. Partners in the Alaska Harmful Algal Bloom monitoring network began monitoring in 2008 and thus were able to provide an early warning of a widespread PSP event near Ketchikan in 2011, and the environmental conditions preceding a shellfish closure resulting from paralytic shellfish toxins near Mosman Island in southeast Alaska in 2012. A comprehensive and integrative communication network between Alaska Harmful Algal Bloom monitoring network personnel and state managers, health professionals, shellfish growers, and the general public is proposed to protect human health and promote safe shellfish harvest in Alaska.