Two-phase uptake of nickel in the ground beetle Pterostichus oblongopunctatus (Coleoptera: Carabidae): implications for invertebrate metal kinetics.
We studied nickel (Ni) kinetics in the ground beetle Pterostichus oblongopunctatus exposed to different, potentially stressful, temperatures. We found unexpected Ni kinetics in metal-exposed adult and larval beetles. Instead of the pattern observed commonly for other metals, i.e., an increase in metal concentration followed by stabilisation in the uptake phase and a decrease after transfer to uncontaminated food, the Ni-fed beetles apparently switched to decontamination soon after the start of Ni exposure while they were still being fed Ni-spiked food. In addition, internal body Ni concentrations showed high variance. The traditional first-order, one-compartment model with the switch to decontamination set to the last day of the uptake phase appeared inadequate and in most cases was nonsignificant. Instead, the model with a regression-estimated point of switching to decontamination fit the data better, explaining 57.2-91.5% of the temporal variability of mean Ni body concentrations (weighted regression) in adult beetles and 44.1-62.3% in larvae. Temperature did not affect Ni toxicokinetics in adults, but in larvae there were some temperature-dependent differences in kinetic parameters.
Bednarska
Agnieszka J
AJ
Institute of Environmental Sciences, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland. a.bednarska@uj.edu.pl
Brzeska
Anna
A
Laskowski
Ryszard
R
D000818:Animals; D001517:Coleoptera / Q000187:drug effects* / Q000378:metabolism; D004785:Environmental Pollutants / Q000493:pharmacokinetics* / Q000633:toxicity; D008658:Inactivation, Metabolic; D007814:Larva / Q000187:drug effects / Q000378:metabolism; D008954:Models, Biological; D009532:Nickel / Q000493:pharmacokinetics* / Q000633:toxicity; D013312:Stress, Physiological / Q000187:drug effects; D013696:Temperature; D013997:Time Factors
D004785:Environmental Pollutants; D009532:Nickel