Per- and polyfluoroalkyl substances (PFAS) and other contaminants of concern in tribal waters of Montana

Environmental Science: Processes & Impacts
By: , and 

Links

Abstract

We assessed potential exposures to a broad suite of contaminants (inorganic, organic and microbial) in culturally important surface waters from three watersheds in a northern plains Native American community (Apsáalooke [Crow Tribe of Montana]) in south-central Montana, United States, with water insecurity concerns. Inorganic (37), organic (435) and microbial (3) constituents were assessed in 12 surface water sites from the Pryor Creek (n = 2), Bighorn River (n = 2) and Little Bighorn River (n = 8) valleys. Twenty-six organics, 33 inorganics and Escherichia coli were detected. Despite relatively low concentrations in surface waters within the Crow Reservation, mixture toxicity indicated prevalent chronic ecological effects and human-health secondary contact (recreation) effects at multiple sites. Further, to address Tribal concerns over the prevalence and corresponding risks of per- and polyfluoroalkyl substances (PFAS), we sampled water, sediment, biofilms and fish at a limited number of locations in the Little Bighorn River. Results indicated that PFAS were prevalent in fish tissues, including whole blood and filets, and to a lesser extent in biofilms, despite few detections in water and sediment samples. This is the first attempt to document environmental PFAS contamination within the reservation and the potential human-health concerns for the general population from consumption of recreational/subsistence fish. Overall, this effort provided preliminary information on the contaminant mixtures present and their potential health implications, which can support the protection of community health and culturally meaningful resources across the Crow Reservation.

Suggested Citation

Smalling, K., Bradley, P., Romanok, K., Doyle, J.T., Eggers, M.J., Martin, C., Barnhart, E.P., Binette, P., Castro, E.M., Chavez, M., Ewing, S.A., Gordon, S.E., Fields, M.W., Gray, J.L., Groshong, A.M., Hwang, C., Kanagy, L.K., LaFrance, J.W., Loftin, K., Long, C.M., McCleskey, R., Meppelink, S.M., Richards, C.L., Schreiner, M., Shikany, J.I., Tesfamariam, M., 2026, Per- and polyfluoroalkyl substances (PFAS) and other contaminants of concern in tribal waters of Montana: Environmental Science: Processes & Impacts, 19 p., https://doi.org/10.1039/d5em00565e.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Per- and polyfluoroalkyl substances (PFAS) and other contaminants of concern in tribal waters of Montana
Series title Environmental Science: Processes & Impacts
DOI 10.1039/d5em00565e
Edition Online First
Year Published 2026
Language English
Publisher Royal Society of Chemistry
Contributing office(s) New Jersey Water Science Center
Description 19 p.
Country United States
State Montana
Additional publication details