Assessing the impact of waterborne and dietborne cadmium toxicity on susceptibility risk for rainbow trout

The purpose of this study was to use a risk-based integrated-scale toxicological model to examine the impact of waterborne and dietborne cadmium (Cd) toxicity on rainbow trout (Oncorhynchus mykiss) susceptibility appraised with recent published data. A probabilistic assessment model was performed to estimate Cd susceptibility risk. The dose-response models were constructed based on two endpoints of % Cd in metabolically active pool (MAP) and susceptibility time that causes 50% effect (ST50). We further constructed an elimination-detoxification-recovery scheme to enhance the model predictive ability. We found a 95% probability of % Cd in gill and liver MAP exceeding 47-49% and it was likely (70% probability) to have exceeded 52-55%, but it was unlikely (30% probability) to have exceeded 56-60%. In contrast to gill and liver, gut had a relative lower Cd susceptibility risk (15-17% Cd in MAP) with a longer ST50. We suggested that the proposed probabilistic risk assessment framework can incorporate the elimination-detoxification-recovery scheme to help government based biomonitoring and bioassessment programs to prevent potential aquatic ecosystems and human health consequences.