Hazard 



Identification & 



Dose-Response 



Assessment 



< 



Is Substance 

 Potentially 

 Hazardous'' 



Physical-Chemical 



Characterization And 



Bioaccumulation Potential 



Environmental Partitioning, 



Degradation. Transport 



Mechanisms, and Potential 



Exposure Media 



Metabolism and 

 Pharmacokinetic Properties 



Toxic Effects in Humans 

 and Laboratory Animals 



Quantitative Relationships 



Weight of Evidence 



\ ►T^NoJ ^ Stop 



<Are Data ^^ -.^^ 



Sufficient For a ^ fci rj | ^ 



Quantitative Risk / ^INol W 

 Assessment? ^ ^*"^ 



e.g., Structure-Activity 

 Relationships, Kq^^,, 

 Bioconcentration Factors 



e.g., Air, Water. Sediments, 

 and Biota 



e.g., Lipophilicity, Bioactivatton, 

 ToxiflcatJon/Detoxidcation, 



Target Organs. Elimination 



e.g., Acute and Chronic 

 Toxicity. Carcinogenic Potency, 



Epidemiologic Evidence 



e.g., Dose-Response Relations. 

 Carcinogenic Potency 



e.g.. Adequacy and Quality 

 of Data, Likelihood of 

 Specific Toxic Effects 



Qualitative Risk Determination Based on 

 Toxicological Properties and Limited Exposure Data 



