Concentrations of Metals in Fishes from the Athabasca and Slave Rivers of Northern Canada

Abstract

There is growing concern about possible effects of exploitation of the Alberta Oil Sands on the ambient environment, including possible effects on populations of fishes in the Athabasca River and farther downstream in Lake Athabasca and the Slave River. In the present study, concentrations of metals in dorsal muscle tissue of 5 fish species-goldeye, northern pike, walleye, whitefish, and burbot-from the Slave, Peace, and Athabasca Rivers were quantified. A suite of 25 metals including As, Hg, Se, Tl, and V was analyzed. Most metals exhibited no significant variations in concentration among locations. Concentrations of 5 metals, As, Hg, Se, Tl, and V, revealed significant variations among locations and were of sufficient magnitude to be of interest. Concentrations of Hg did not vary significantly among locations; however, because it was detected at concentrations of concern and the use of the selected fishes was a local source of food for humans and pets, it was of interest. Concentrations of As, Se, Tl, and V in dorsal muscle of certain fishes in the farthest downstream sites on the Slave River were greater than those in the same tissues and species in the farther upstream sites on the Peace and Athabasca Rivers. This phenomenon was most prevalent with Tl and to a lesser extent with As and Se. Nevertheless, concentrations were not of concern for the health of human consumers. Although metals did not appear to be increased in fish in the Alberta Oil Sands region in the present study, further research is needed to understand the potential impacts.

Method Validation for Determination of Thallium by Inductively Coupled Plasma Mass Spectrometry and Monitoring of Various Foods in South Korea

“…Tl levels in fishes varied from 0.41 to 1.87 µg kg −1 , with the mean value of 1.06 µg kg −1 . These values were higher than those in a Vietnamese study (0.012-0.050 µg g −1 ), but similar to those in the Canadian (0.01-19.26 ng g −1 ) and Iranian (0.02-0.30 µg kg −1 ) ones [33][34][35]. As for cephalopods, we analyzed squid and octopus, and their average Tl content was 1.10 µg kg −1 .…”

Potential Influence of Sewage Phosphorus and Wet and Dry Deposition Detected in Fish Collected in the Athabasca River North of Fort McMurray

“…Furthermore, data on the concentrations of biotransformation products of PACs in the bile of northern pike (Esox lucius) collected in the summer of 2011 were also elevated following the Richardson Fire [37]. While similar spatial and temporal patterns are somewhat supported by PAHs measured in the muscle of these same fish [81], no patterns were apparent in concentrations of metals [82]. These data support the potential role of forest fires in the associations between the performance of fish health and precipitation.…”

“…Our work especially suggests the importance of including environmental covariates into surveillance monitoring in areas like the OSR where most influences are diffuse. If novel sources of variability emerge, or the existing relationships described with the covariates we have used changes, the observed variability may begin to drift out of the expected range or show other improbable patterns [82]. However, additional work to better test our hypotheses may also be used.…”

A critical review of the ecological status of lakes and rivers from Canada's oil sands region

“…Other data also suggest little evidence of a local industrial source in Hg of fish muscle (Tendler et al, 2020 ), but does show that tissues of sport fishes, such as walleye and pike, can exceed consumption and subsistence guidelines (Tendler et al, 2020 ). Temporally, Hg has been measured in fishes captured in the OSR since 1976.…”