|The results of the national-scale assessment will provide important information to help EPA continue to develop and implement various aspects of the national air toxics program. They will not be used directly to regulate sources of air toxics emissions. While regulatory priority setting will be informed by this and future national assessments, risk-based regulations will be based on more refined and source-specific data and assessment tools. More specifically, the assessment results will help to:
- Identify air toxics of greatest potential concern.
- Characterize the relative contributions to air toxics concentrations and population exposures of different types of air toxics emissions sources (e.g., major, mobile).
- Set priorities for the collection of additional air toxics data and research to improve estimates of air toxics concentrations and their potential public health impacts. Important additional data collection activities will include upgraded emission inventory information, ambient air toxics monitoring, and information on adverse effects to health and the environment.
- Establish a baseline for tracking trends over time in modeled ambient concentrations of air toxics.
- Establish a baseline for measuring progress toward meeting goals for inhalation risk reduction from ambient air toxics.