In rural Alaska, native communities rely heavily on subsistence fishing for food. To assess food safety, we tested salmon and shellfish harvested by tribe members for contaminants, parasites, and diseases. Our objective is to help the tribal communities of Nanwalek, Port Graham, and Seldovia determine if their subsistence fish and shellfish are safe for consumption.
Why We Care
Pollutants from oil spills, abandoned mines, glacial-melt water and long-range atmospheric transport find their way into coastal biological resources and have the potential to impact human health, especially for populations that rely heavily on subsistence food sources. Native Alaskans do not know the degree to which they may be exposed to pollutants and other waterborne contaminants because wild-caught subsistence food resources are not routinely tested nor monitored for safety in Alaska.
What We Have Done
We began by training community members to conduct field work and handle samples. Two species of salmon (chum and sockeye salmon) and shellfish (cockles and softshell clams) were collected from traditional subsistence harvest grounds of the tribal villages of Nanwalek, Port Graham, and Seldovia. To characterize the overall health of the fish and shellfish we have quantified the shellfish tissue, fish livers, and fish muscles for a range of contaminants, including toxic metals (e.g., lead and mercury) and persistent organic pollutants (e.g., DDT, PAH, and PCB). We have also assessed the fish and shellfish for parasites (e.g., worms) and diseases (e.g., tumors).
Our study has provided reliable information on the degree of contamination, presence of disease, and occurrence of parasites in salmon and shellfish commonly used for subsistence food in south central Alaska. The information we generate is also useful to local coastal resource managers.
Partnering with us on this project are the Chugach Regional Resources Commission, Alvtiiq Pride Shellfish Hatchery, NMFS Northwest Fisheries Science Center (NWFSC). The North Pacific Research Board (NPRB) is providing major funding support.
What We Found
Taken together, our contaminant body burden and histopathological results of the softshell clams, cockles, and chum and sockeye salmon showed that the fish and shellfish were healthy and non-contaminated. Hence, they can be safely consumed.