Development of a physiologically based pharmacokinetic (PBPK) model for cobalt in the Chinese population based on population exposure data

Cobalt is a critical raw material for consumer electronic products such as electric vehicles and mobile communication devices. Currently, its recovery rate remains relatively low, resulting in a large amount of waste cobalt entering soil and groundwater environments, which poses a potential threat to human health. Previous studies have mostly focused on the effects of acute cobalt exposure. However, the in vivo metabolic mechanism of long-term low-dose cobalt exposure remains unclear, and the long-term toxic effects of cobalt on the heart await further investigation. Based on the existing model framework, this study constructed a cobalt Physiologically based pharmacokinetic (PBPK) model incorporating a heart compartment, filling the research gap in this field. Meanwhile, the study calibrated the parameters of the PBPK model by integrating the specific exposure scenarios and dietary exposure characteristics of the Chinese population, and conducted model evaluation and evaluation using epidemiological data of the Chinese population. With the help of Monte Carlo simulation (MCS) technology, this study conducted an in-depth analysis of the inter-individual exposure and metabolic characteristics. The results showed that the deviation between the cobalt concentrations in blood, urine, liver, kidneys, and heart of the Chinese population predicted by the model and the measured values was basically controlled within a 2-fold range. The cobalt PBPK model constructed in this study provides a key tool for the accurate risk assessment and practical application of cobalt exposure in the Chinese population, and also offers a referable research paradigm for accurate risk assessment under the specific characteristics of different ethnic groups.