The Oregon Health Authority is issuing recommendations on the amount of resident fish, shellfish and crayfish from the Multnomah Channel and Scappoose Bay that people should eat.
Fish tissue data that Oregon Department of Environmental Quality collected show high levels of polychlorinated biphenyls, or PCBs, and dioxins and furans in resident fish, shellfish and crayfish in Multnomah Channel and Scappoose Bay. Meal recommendations are needed, according to public health officials.
Multnomah Channel is a 21.5-mile branch of the Willamette River in Portland. The channel flows northerly next to the west side of Sauvie Island until it meets the Columbia River near St. Helens in Columbia County. Scappoose Bay, near St. Helens, includes former and current industrial sites that have contributed to contaminant concentrations in the bay.
The map provided shows the extent of the Multnomah Channel and Scappoose Bay.
OHA issues advisories when fish or shellfish tissue data verify that the levels of contaminants — in this case, PCBs and dioxins and furans — are above Oregon’s health-based screening values. OHA then calculates meal recommendations using these data to help people better understand the amount of resident fish and shellfish they can safely eat in one month.
Resident fish such as large- and smallmouth bass, carp, walleye, catfish, perch, black crappie, bluegill, largescale sucker and other species live in the same area their entire life. Some, like bass and walleye, are long-lived top predators, eating other contaminated fish within the channel and bay. The longer they live, the more PCBs, dioxins and furans these fish accumulate. Other fish, such as carp, suckers and catfish, are bottom feeders. PCBs, dioxins and furans can build up in these types of fish because they live and eat in areas with high levels of these contaminants.
This advisory does not apply to migratory fish such as salmon, steelhead, trout or shad that spend most of their lives in other places beyond the channel and bay. These and other migratory fish are a healthy choice when considering what fish to eat.
People who eat too many resident fish and shellfish contaminated with PCBs, dioxins and furans can suffer negative health effects over time. These health effects include damage to organs, the nervous system and the brain, leading to potential learning and behavior problems. Mothers can pass these contaminants to their babies during pregnancy or in breastmilk. Fetuses, babies and small children are most vulnerable to the health effects of PCBs, dioxins, and furans.
While it is important for people to know about contaminants in fish and shellfish, it is equally important to continue to eat at least two meals of a variety of fish each week to gain important health benefits. Fish are high in protein, low in fat and rich in nutrients like omega-3 fatty acids. Omega-3s provide protection from heart disease and are an important brain food for adults, children and fetuses.
As future data becomes available from Multnomah Channel and Scappoose Bay, OHA will evaluate and update the advisory meal allowances as needed. For a list of other areas and water bodies with existing fish advisories and recommended meal allowances, visit the OHA fish advisory webpage. https://www.oregon.gov/OHA/PH/HealthyEnvironments/Recreation/FishConsumption/Pages/fishadvisories.aspx