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EPA Chemical Data Screening, Review, and Characterization
EPA is reviewing submitted data on the approximately 1,400 chemicals sponsored directly in the HPV Challenge Program. (Over 860 chemicals have also been sponsored indirectly through the International Council of Chemical Associations (ICCA) HPV Initiative 
.) The data are being reviewed for quality and completeness, and EPA is preparing documents that characterize any hazards associated with these chemicals.
A chemical-screening process consisting of two tiers is being used to review and characterize the data. In Tier I, EPA uses a hazard-based screening process to prioritize the order in which data submissions are reviewed. In Tier II, EPA is evaluating the data within each submission and characterizing the hazard potential of each chemical or chemical category.
- About Prioritizing HPV Chemicals - Information on the order in which chemical data from the program will be reviewed and characterized by EPA. The list is generated by the High Production Volume Information System (HPVIS).
- About HPV Chemical Hazard Characterizations - EPA documents available in HPVIS that characterize specific hazards associated with HPV chemicals. Hazard characterizations are prepared during review of the quality and completeness of data contained in each HPV Challenge Program submission. Data reviews are performed according to established HPV Challenge Program guidelines and EPA risk assessment guidance.