Risk Assessment Strategies and Techniques for Combined Exposures

摘要: Consideration of cumulative risk is necessary to evaluate properly the safety of, and risks associated with, combined exposures. These exposures (“mixtures”) commonly occur from exposure to: environmental contaminants in air, soil, water; pharmaceuticals dietary supplements; consumer personal care products; food additives residues; nonchemical stressors (e.g., physical psychosocial). Risk assessments mixtures chemicals are more complex than those single for two major reasons: (1) combining estimate mixture risk, it rely on multiple assumptions; (2) potential pharmacokinetic and/or pharmacodynamic interactions among components. Additional difficulties exist mixtures, which typically contain a large fraction total mass unknown identity toxicity. The influence data type, quality quantity assessment approach illustrated. Guidance provided when whole approaches possible component-based needed. Advantages disadvantages discussed, including concerns due current status sufficient similarity methodology. Component-based methods based dose-addition represent majority chemical that have been conducted date; both hazard index-based (Hazard Index, Target Organ Toxicity Hazard Interaction-Weighted Index) index (Relative Potency Factor Toxic Equivalency Factor) reviewed. There recognition need consider effects stressors, but standard with history use not available.