Toxicokinetic modeling of ( super(14)C)pentachlorophenol in the rainbow trout (Salmo gairdneri )

An in vivo trout model was used to monitor the major routes and rates of pentachlorophenol uptake and elimination. Rainbow trout exposed to a mean sublethal water concentration (1.0 mu g/l) of ( super(14)C)pentachlorophenol (PCP), a moderately lipophilic, relatively non-persistent environmental contaminant acquired a mean calculated dose of 230 mu g/kg per 48 h and a mean measured dose of 212 mu g/kg per 48 h. The rate constants determined for the calculated and measured doses were 5.0 and 4.6 l/kg per h, respectively. This close agreement between the calculated and measured doses and their rate constants provided further support for the use of this model system in aquatic toxicokinetic studies. A first-order kinetic model and observed data were used to generate fitted and predicted rate constants required for evaluation of first-order kinetics. The fitted first-order uptake-depuration curves for all experimental animals agreed with those observed suggesting first-order kinetics approximated the behavior of whole-body PCP burden.