Session 3: The RISK21 Approach
RISK21 is a tiered methodological approach for the systematic collection and highly visual representation of toxicological and exposure data to assess risk to human health.
RISK21 is problem formulation - based and exposure driven, utilizing and generating data with enough precision to make a decision to assure safety. The precision of the data used to make that decision is often a function of the quanti ty and quality of available data.
Even with little information, estimates of exposure can be made based on physical chemical characteristics such as water solubility or volatility and conservative assumptions or scenarios.
If additional precision is necessary, models and databases, such as those described in the EPA EXPOsure toolbox, can be used to develop a better estimate of exposure.
RISK21 tested this methodological approach with a case study involving 20 chemicals in drinking water to identify which chemicals were of concern. Additional case studies ar e being developed to test and refine the RISK 21 methodology.