The influence of sampling method and season on modeling of selenium into coldwater fish and implications on tissue‐based water quality benchmarks.

This article focuses on modeling selenium (Se) bioaccumulation in four coldwater fish species—northern pike (Esox lucius), white sucker (Catostomus commersonii), lake whitefish (Coregonus clupeaformis), and ninespine stickleback (Pungitius pungitius)—inhabiting boreal lakes downstream from a uranium mill in northern Canada. It evaluates how benthic macroinvertebrate (BMI) and periphyton sampling methods (artificial substrates versus sediment grab samples), seasonal variation (summer versus winter), and two biodynamic models—the U.S. Environmental Protection Agency (USEPA) model and the Assessment of the Dispersion and Effects of Parameter Transport (ADEPT) model—influence estimated Se concentrations in fish tissue. Results indicate that sediment grab sampling better reflects observed Se concentrations in fish, particularly at high-exposure sites, while artificial substrates tend to overestimate Se bioaccumulation. Seasonal differences showed significantly lower Se body burdens in winter, suggesting temporal variability in Se exposure risks. The study underscores the importance of selecting appropriate sampling methods and seasons for accurate Se risk assessment and highlights the need for further research on seasonal Se dynamics and toxicity thresholds in coldwater fish species.