Risk Assessment and Critical Thinking
Rule of Evidence: See point 6. 8. Experimental Evidence: Do laboratory animals show a similar effect ? Rule of Evidence: Considering also points 6 and 7, findings in laboratory animals are supportive of a causal association. However, materials such as cigarettes and arsenic that are notably carcinogenic to humans have tested negative in animal studies . 9. Analogy: Do structurally similar chemicals cause similar effects ? Rule of Evidence: For some classes of compounds, such as nitrosamines, structure-activity predictions can be supportive of a causal association.