A new TK model approach to assess the effect of migration on copper toxicokinetics in inbred populations of the flour beetle, Tribolium castaneum

Abstract

The aim of the study was to determine the influence of migration on copper (Cu) kinetics of male Tribolium castaneum after 25 generations of exposure for Cu-adapted and non-Cu-adapted inbred lines. Adapted lines were kept on a flour medium contaminated with 1000 mg Cu kg−1. A medium contaminated with 2000 mg Cu kg−1 of copper was used during the intoxication phase. Based on our data and literature reports, we introduced a new two-phase four-stage toxicokinetics (TK) model. The intoxication phase was successfully divided into three stages with separate assimilation rate constant (ka) and elimination rate constant (ke) values. The influence of migration was examined by comparing ka and ke parameters confidence intervals. In non-contaminated environments, migrants significantly increased ka and ke values in the second stage. Migrants decreased the maximum Cu accumulation observed in the experiment. The results indicated that the TK model must show high goodness-of-fit to be a useful tool for comparing treatments.