Seafood Safety Check

Ellen Preece wants to know if microcystins, liver-damaging toxins produced by algal blooms in freshwater lakes, accumulate in Puget Sound seafood. Thanks in part to a grant from the Natural Resource Conservation Endowment Fund and a number of other like-minded sources, she’s not the only one who will soon find out.

Ellen Preece
Ellen Preece prepares a mussel sample for
testing in the lab.
Photo by Megan Skinner, WSU

Preece, a doctoral student in the WSU School of the Environment (SoE), is helping the Washington Department of Health determine whether seafood accumulates enough microcystins to be a health concern for populations who rely on locally harvested seafood for food.

Microcystins are a group of amino acids produced by cyanobacteria (blue-green algae) that thrive in freshwater lakes with high water temperatures and excess nutrients such as nitrogen and phosphorous. The problems have been traced to sewage, fertilizer, detergent, and animal waste. Previously found only in freshwater lakes, microcystins are now showing up in saltwater.

Applying Lessons Learned

News that recent sea otter fatalities on the California coast have been attributed to microcystins coming from freshwater lakes alerted regional scientists to the possibility that the same toxins could show up in Puget Sound shellfish.

“The Washington Department of Health is very interested in understanding this potential exposure pathway,” said Joan Hardy, a toxicologist with the agency. Lakes in Kitsap and Pierce Counties are suspected contributors to the growing risk.

Recent immigrants (often from Asia) regularly depend on shellfish they harvest from the shores of Puget Sound as a protein source. A USGS Western Ecological Research Center study suggests that consuming saltwater shellfish harvested near river mouths could pose a risk to people because of the freshwater toxins.

Preece is also investigating microcystins on the Colville Indian Reservation, where tribal members fish for rainbow trout in lakes with poor water quality.

A Matter of Detection

A syringe poking the inside of a mussel.
Measuring contaminants in mussels.
Photo courtesy Pacific Northwest National Laboratory

Preece’s research focuses on refining methods for detecting microcystins in seafood. Using mussels collected from Puget Sound, she is developing protocols for a technique that can determine which variants of the microcystins are present at what concentrations. She is also developing standard methods for health agencies to use a more common, less expensive tool to screen for microcystins in fish and shellfish.

Both techniques provide information that is critical for assessing whether seafood poses a potential health risk. “We’re counting on Ellen’s interest in the analytical issues associated with this problem so that the Department of Health can give sound advice to the public,” Hardy said.

According to Preece, if a changing climate results in higher lake temperatures, we could see increases in these toxic algal blooms in freshwater lakes. Hardy agrees that climate change may be at play and that monitoring is warranted. “We’re really just beginning to look at climate change and whether it’s a factor in freshwater toxic algal blooms. We need to carefully monitor lakes over time to see if there is a trend in toxicity linked to changing temperatures or other environmental factors.”

Fuel for the Findings

Preece conducts her research in the limnology lab of Dr. Barry Moore in the WSU SoE. In addition to support from the Natural Resource Conservation Endowment Fund, she has also received an EPA STAR graduate fellowship. Other related partnerships are with the Washington Department of Ecology, departments of health in Kitsap and Pierce Counties, the King County Environmental Laboratory, and the Colville Confederated Tribes. Preece expects to complete her doctoral program in 2014.

– by Sylvia Kantor

The Natural Resource Conservation Endowment Fund was established by Jane P. Conrad and entrusted to Washington State University in 1982. The purpose is to provide seed money for domestic and international research and projects related to energy, conservation, small-scale agricultural concepts, community education, natural resources, and wildlife. Supported work is oriented toward practical application of theory to provide stakeholders with maximized opportunities to benefit.