The Uptake of I^(131) by the Biota of Fern Lake, Washington, in a Laboratory and a Field Experiment

Abstract

The distribution of I131 among the biota of Fern Lake, Washington, was compared in aquarium and field experiments. The samples for study in the laboratory were isolated in containers so that the water solution, and not food, was the major source of the radionuclide. The field experiment related the uptake of I131 by organisms isolated in containers to the accumulation by those with access to their usual sources of food. In the aquarium, the initial concentration of I131 was 8,000 times the average concentration calculated for the lake experiment. Maximum concentration factors ranged from 1.7 and 2.6 for the muscle of trout and crayfish, respectively, to 280 for the "thyroid" of trout, 380 for Nitella, and 600 for an amphipod. I131 was not detected in a number of samples collected from the lake, but accumulation factors were as high as 1,400 for Nitella clumps and 12,000 for the "thyroid" of trout. Young microcrustaceans, which are able to accumulate iodine directly from water, were an important source of I131 for trout.

Baseline risk assessment of groundwater contamination at the Uranium Mill Tailings Site near Gunnison, Colorado

“…26 multiplied by [1-0.77] = 0.06mg/kg). The converted concentration of 0.06 mg/kg is less than the concentration of 28 mg/kg detected in muscle tissue from the literature study (Short et al, 1971).…”

Baseline risk assessment of groundwater contamination at the uranium mill tailings site, near Gunnison, Colorado. Revision 2

“…For comparative purposes, the dry weight concentration of molybdenum detected in the fish muscle tissue sample from the Gunnison River (0.26 mg/kg) was converted to fresh weight by using the average moisture content of 77 percent from the tissue samples (0.26 multiplied by [I -0.771, = 0.06 mg/kg). The converted concentration of 0.06 mg/kg is less than the concentration of 7 mg/kg detected in muscle tissue from the literature study (Short et al, 1971 ).…”

“…In a study involving rainbow trout, no adverse effects were noted in fish having a muscle tissue molybdenum concentration of 7 mg/kg fresh weight (Short et al, 1971). For comparative purposes, the dry weight concentration of molybdenum detected in the fish muscle tissue sample from the Gunnison River (0.26 mg/kg) was converted to fresh weight by using the average moisture content of 77 percent from the tissue samples (0.26 multiplied by [I -0.771, = 0.06 mg/kg).…”

Literature review of the concentration ratios of selected radionuclides in freshwater and marine fish

“…CR values for fish muscle ranged from 330 to 420 for predatory fish to 660 to 1480 for plantivorous-omnivorous species. Trophic level discrimination also has been observed in marine systems (Pearcy and Vanderploeg,266 Eisler 77 ). Muscle levels in plantivorous fish (10.5 to 23.7 ppm) were significantly higher than levels in piscivorous fish (5.2 to 7,5 ppn1).…”