Advancing Health Risk Assessment: Integrating Exposure Routes and Bioavailability to Quantify Internal Dose

As the linkage between environmental pollution and health outcomes, exposure routes characterize how pollutants enter the human body, constituting the foundation of health risk assessment. Pollutants primarily enter body through three major routes: ingestion, inhalation, and dermal contact. The exposure routes govern the internal dose, tissue distribution, and metabolic fate of various environmental pollutants, fundamentally shaping the nature and magnitude of associate health risks. From the perspective of exposure routes, current risk assessment models exist several limitations, including the lack of systematic integration across multiple exposure routes; reliance on fixed default exposure parameters that fail to reflect population heterogeneity; dependence on external exposure dose such as daily intake, without accounting for bioavailability; and omission of special exposure routes. Therefore, modern health risk assessment frameworks must evolve to incorporate: integrated multi-route exposure assessments, probabilistic parameter distributions, and bioavailability-corrected effective dose. Only through such comprehensive improvements can achieve accurate characterization of exposure risks and provide a robust scientific basis for precision prevention and control.