Research aquatic biologist, U.S. Environmental Protection Agency, Corvallis, OR
Pages: 18 Published: Jan 1985
Laboratory research, primarily with salmonid fish, has demonstrated that metal acclimation can increase metal tolerance. Although slight decreases in tolerance have been reported following acclimation, reports of approximate doublings in tolerance predominate. The magnitude of increased tolerance may be metal-specific, and available data suggest the magnitude of acquired tolerance follows the series: Zinc > Copper > Cadmium > Chromium. Tolerance appears to change within a week of major changes in acclimation concentration.
The significance of acclimation-induced tolerance may be important to the survival of organisms in metal-contaminated environments, but the magnitude of the tolerance change is probably within the range of many other factors influencing the accuracy of criteria. For example, the use of mean concentrations to express cycling exposure may underestimate chronic toxicity by a factor of two. Metal speciation/complexation is probably much more important to criteria accuracy than acclimation. Another important aspect of criteria evaluation is the relative resolution of laboratory tests and field monitoring. The problem of detecting biological effects following criteria violations is discussed.
acclimation, acclimatization, resistance, tolerances (physiology), incipient lethal level (ILL), LC, 50
Paper ID: STP33569S