Assessing chemical carcinogenicity: hazard identification, classification, and risk assessment. Insight from a...

Area of Science:

• Toxicology
• Chemical Carcinogenicity
• Risk Assessment

Background:

• An international workshop addressed challenges in chemical carcinogenicity assessment.
• Key topics included modes-of-action, dose-response, and New Approach Methodologies (NAMs).

Purpose of the Study:

• To identify challenges and knowledge gaps in chemical carcinogenicity assessment.
• To explore the integration of NAMs into hazard identification and risk assessment.
• To propose a framework for advancing carcinogenicity risk assessment.

Main Methods:

• Convened an international state-of-the-science workshop.
• Organized discussions around problem formulation, modes-of-action, dose-response, and NAMs.
• Developed a decision matrix for carcinogenicity assessment.

Main Results:

• Acknowledged limitations of traditional rodent bioassays.
• Identified knowledge gaps for the development and uptake of NAMs.
• Highlighted the need for integrated and defined approaches for testing and assessment.

Conclusions:

• Single NAMs are unlikely to replace traditional bioassays; integrated approaches are needed.
• Adverse outcome pathway networks can aid evidence organization.
• A decision matrix was proposed to guide carcinogenicity assessment.