Recent testing conducted by the Utah Department of Environmental Quality and the Utah Division of Wildlife Resources found that some species of waterfowl contain elevated levels of mercury and perfluorooctanesulfonic acid (PFOS).
According to an assessment by the Utah Department of Health and Human Services, eating more than the advised amounts of Northern shoveler (mercury) or gadwall and mallard (PFOS) harvested around the Great Salt Lake could result in exposure above health recommendations. Additionally, mercury advisories have been removed for common goldeneye, as the most recent sampling data indicate that levels have dropped below the Environmental Protection Agency’s health based guideline.
The data evaluated for the advisory decisions were based on sampling a wide range of waterfowl (16 species in 2022 and 9 species in 2025) summarized below:
- 2025 Data Summary for Mercury and PFOS in Waterfowl Tissue
- 2022 Data Summary for Mercury in Waterfowl Tissue
Mercury in waterfowl tissue
Mercury is a naturally-occurring metal that can be transformed into methylmercury, a toxic form found in some lakes and rivers. Women who are pregnant or may become pregnant, women who are breastfeeding, and young children are most at risk to methylmercury exposure, because even small amounts over time can affect brain and nervous system development.
Read more about mercury and your health
PFAS in waterfowl tissue
PFOS is a man-made chemical belonging to a group of Per- and polyfluoroalkyl substances (PFAS) contaminants, often called ‘forever chemicals’ because they break down very slowly. PFAS have been widely used in many products and are now found in the environment and consumer goods. Repeated exposure to PFOS above certain levels has been linked to problems with cholesterol, the immune system, liver function, and small decreases in birth weight.
For more information about PFAS and your health, visit the Agency for Toxic Substances and Disease
For more information about DEQ’s PFAS Program
Consumption Advisories
The Environmental Epidemiology Program (EEP) completed a health consultation recommending that a consumption advisory for waterfowl harvested from the Great Salt Lake marshes be issued because of the elevated levels of PFOS or mercury detected.
| Species | Contaminant | Maximum Meals Per Month | ||
|---|---|---|---|---|
|
Adults; Men > 16 years Women > 50 years (8 oz meal size) |
WCB* Children 6-16 years (8 oz meal size) |
PW*; Children < 6 years (4 oz meal size) |
||
| Northern Shoveler | Mercury | 4 | 1 | Do Not Eat |
| Gadwall | PFOS | 4 | 4 | 2 |
| Mallard | PFOS | 5 | 5 | 2 |
*Abbreviations: WCB = women of childbearing age; PW = pregnant and breastfeeding women
Public health action plan
The Environmental Epidemiology Program of the Utah Department of Health and Human Services will continue to work with the Utah Department of Environmental Quality, the Utah Division of Wildlife Resources, and local health departments on the development of waterfowl sampling and monitoring plans for Utah.
Resources
Press Releases
Links
- Agency for Toxic Substances and Disease Registry
- American Heart Association
- Environmental Protection Agency fish advisories
- U.S. Food and Drug Administration fish advisories
- Utah Department of Environmental Quality
- Utah Department of Health
- Utah Department of Natural Resources
Contacts
Utah Department of Environmental Quality Division of Water Quality
P.O. Box 144870Salt Lake City, Utah 84114-4870
Phone: (801) 536-4300
Fax: (801) 536-4301
Utah Department of Health Environmental Epidemiology Program
P.O. Box 142104 Salt Lake City, Utah 84114-2104Phone: (801) 538-6191
Fax: (801) 538-6564
Utah Department of Natural Resources Division of Wildlife Resources
P.O. Box 146301 Salt Lake City, UT 84114-6301Phone: (801) 538-4700
Fax: (801) 538-4745