Development and evaluation of a regression-based model to predict cesium concentration ratios for freshwater fish.
Data from published studies and World Wide Web sources were combined to produce and test a regression model to predict Cs concentration ratios for freshwater fish species. The accuracies of predicted concentration ratios, which were computed using 1) species trophic levels obtained from random resampling of known food items and 2) K concentrations in the water for 207 fish from 44 species and 43 locations, were tested against independent observations of ratios for 57 fish from 17 species from 25 locations. Accuracy was assessed as the percent of observed to predicted ratios within factors of 2 or 3. Conservatism, expressed as the lack of under prediction, was assessed as the percent of observed to predicted ratios that were less than 2 or less than 3. The model's median observed to predicted ratio was 1.26, which was not significantly different from 1, and 50% of the ratios were between 0.73 and 1.85. The percentages of ratios within factors of 2 or 3 were 67 and 82%, respectively. The percentages of ratios that were <2 or <3 were 79 and 88%, respectively. An example for Perca fluviatilis demonstrated that increased prediction accuracy could be obtained when more detailed knowledge of diet was available to estimate trophic level.
Department of Environmental and Radiological Health Sciences, Colorado State University, 305 W. Magnolia PMB 231, Fort Collins, CO 80521, USA. Electronic address: jepinder@uga.edu.
John E
JE
Pinder
Atomic Energy of Canada Limited (AECL), Environmental Technologies Branch, Chalk River Laboratories, Chalk River Ontario K0J 1J0, Canada. Electronic address: djrowan@bell.net.
David J
DJ
Rowan
Department of Biological Sciences, University of Lethbridge, Lethbridge, Alberta T1K 3M4, Canada. Electronic address: Joseph.rasmussen@uleth.ca.
Joseph B
JB
Rasmussen
School of Earth and Environmental Science, Science University of Portsmouth, Portsmouth P01 3 QL, UK. Electronic address: Jim.smith@port.ac.uk.
Jim T
JT
Smith
Star Network of Excellence in Radioecology, Institute for Radiation Protection and Nuclear Safety, Saint-Paul-lez-Durance 13115, France. Electronic address: Thomas.hinton@irsn.fr.
Thomas G
TG
Hinton
Department of Environmental and Radiological Health Sciences, Colorado State University, 305 W. Magnolia PMB 231, Fort Collins, CO 80521, USA. Electronic address: Ward.Whicker@colostate.edu.
F W
FW
Whicker
D000818:Animals; D002586:Cesium / Q000032:analysis*; D005399:Fishes / Q000378:metabolism*; D005618:Fresh Water
D002586:Cesium
Cs concentration ratios; Freshwater fish; K concentrations; Predictive model; Regression; Trophic levels