About HPV Chemical Risk-Based Prioritizations
As of December 2008, EPA has developed and posted risk-based prioritizations for 151 HPV chemicals and has posted hazard-based prioritizations for fifty-five (55) chemicals.
EPA's Risk-based Prioritizations of High Production Volume (HPV) Chemicals are screening-level documents that:
- Summarize basic hazard and exposure information available to EPA on HPV chemicals;
- Identify potential risks;
- Note scientific issues and uncertainties; and
- Indicate the initial priority being assigned by the Agency for potential future appropriate action.
These screening-level documents will be used by EPA to evaluate chemicals and assign initial priority for future potential action based on the risk concerns presented by these chemicals in comparison with other HPV chemicals and in light of any uncertainties presented by gaps in the available data. The Agency intends to follow-up with voluntary or regulatory actions for HPV chemicals of concern focusing initially on cases presenting special concern. These characterizations and prioritizations do not constitute definitive determinations regarding either risk or the sufficiency of available information for any regulatory purpose, but are rather initial evaluations based upon HPV Challenge Program and IUR data received by EPA.
For a given chemical or chemical category, each Risk-based Prioritization presents an initial recommended level of concern and contains supporting documents, including:
- Hazard Characterization;
- Exposure Characterization; and
- Risk Characterization.
Schedule for Risk Characterization and Prioritization Documents
Under the North American Security and Prosperity Partnership (SPP), the Agency has committed to assess and initiate needed action on approximately 6,750 high and moderate production volume chemicals (based on preliminary statistics from the 2006 IUR data) by 2012. To fulfill commitments made under the SPP, EPA created the Chemical Assessment and Management Program (ChAMP).
In 2008 EPA will complete the first groups of Risk Characterization and Prioritization Documents for HPV chemicals, and efforts will ramp up extensively from 2009 until 2012 to complete commitments for approximately 2,750 HPV chemicals. The Agency is committed to initiate any needed action on the highest priority HPV chemicals during this period. Given the demands of the SPP assessment effort, however, EPA expects that action on other chemicals, if warranted, would be pursued later during this period or after 2012.
Development of Risk-based Prioritizations of HPV Chemicals
Previously, OPPT developed screening-level Hazard Characterizations that consisted of objective evaluations, conducted according to established EPA guidance, of the quality and completeness of the hazard data sets provided by HPV Challenge chemical sponsors. The hazard characterization documents include a critique of available information and documentation regarding data gaps for those chemicals for which further information may be needed, but draw no conclusions regarding whether additional relevant data beyond the submitted information may be of value to the Agency.
In 2006 and 2007, EPA received data on uses of, and reasonably likely exposures to, chemicals on the TSCA inventory, submitted in accordance with the requirements of the IUR. EPA has prepared screening-level Exposure Characterizations based largely on the information submitted under the IUR reporting, although other exposure information submitted to the Agency (for example, in HPV submissions) or readily available through a limited set of publicly accessible databases was also considered, as appropriate.
Information is collected every five years under IUR. The most recent reports pertain to chemicals manufactured in the United States during calendar year 2005 in quantities of 25,000 pounds or more at a site. Information was reported on the identity of the chemical manufactured or imported, the quantity produced, the physical form, and the number of persons reasonably likely to be exposed during manufacture of the chemical.
For chemicals manufactured or imported in quantities of 300,000 pounds or more at a site during calendar year 2005, additional information was reported on the industrial processing and uses of the chemical, including:
- The number of industrial processing sites and of employees reasonably likely to be exposed to the chemical at these sites;
- The consumer and commercial uses of the chemical; and
- An indication whether the chemical is used in products intended for use by children under 14 years of age.
Note about Confidential Business Information (CBI) - While some of the exposure and use data for chemicals may be claimed as confidential and is therefore not presented in public documents, EPA does consider all data submitted to the IUR in its risk characterization process.
The screening-level EPA Exposure Characterization was combined with the screening-level Hazard Characterization to develop a qualitative screening-level Risk Characterization. To ensure that the most current hazard-related information was used in the Risk Characterization, EPA augmented the Hazard Characterization by searching publicly accessible databases for information entered from one year prior to the HPV Challenge submission up through the current year.
EPA's Use of Risk Characterizations to Document Risk-based Prioritizations of HPV Chemicals
EPA screening-level Risk Characterization documents summarize EPA's current thinking regarding the potential risks of HPV chemicals or categories by evaluating and integrating hazard and exposure information available to EPA. The purpose of the qualitative screening-level risk characterizations is to:
- Support an risk-based prioritization which will inform risk management options; and
- Identify potential data needs for individual chemicals or chemical categories.
- Hazard (human health and environment);
- Exposure (general population and environment, workers, commercial workers and consumers, and children); and
- Physical chemical properties and environmental fate (persistence and bioaccumulation).
EPA's Initial Prioritization Concern Groupings
EPA's evaluation of the available screening-level data results in one of three possible concern and priority groupings, which is indicated for each chemical or category in its Initial Prioritization document:
- Low Priority, Follow-up Action Not Suggested at This Time: Information available to EPA on the chemicals or categories assigned to this priority suggests that they do not present significant risk issues that warrant further Agency consideration at this time. This prioritization category may include chemicals with known risks that are already being controlled or addressed by existing activities or regulations.
- Medium Priority, Potential Concern: Information available to EPA on chemicals assigned to this priority suggests possible concerns, including chemicals with risk issues or uncertainties that might be resolved if additional data (e.g. on exposures, controls and/or hazards) were available to provide a basis for evaluating the potential concerns.
- High Priority: Information available to EPA on chemicals assigned to this priority suggests that these chemicals appear to have more serious potential risk concerns. Further analysis may result in identifying a need for risk management actions, regulations, and/or more comprehensive data. High Priority chemicals further designated as "chemicals of special concern" will be the focus of expedited attention.
Follow-up for Medium Priority Chemicals of Potential Concern
EPA generally expects to encourage voluntary actions to better understand or mitigate potential risks. In other cases, EPA may identify the need to act directly via regulatory means. Voluntary actions could include provision of data by companies in response to informal Agency requests or a more structured voluntary program for obtaining hazard, exposure, or exposure mitigation data from industry to further evaluate chemicals of concern. Additionally, voluntary use restrictions, emission reductions, product reformulations, Material Safety Data Sheet (MSDS) modifications, or re-labeling of products could be suggested by EPA to mitigate potential chemical risks. Following review of any voluntary actions on the part of industry, EPA intends in the future to consider whether more concerted voluntary or regulatory actions may be appropriate.
Follow-up for High Priority Chemicals and Chemicals of Special Concern
EPA intends in most cases to encourage prompt voluntary submissions or development of information that would help to clarify hazard, exposure, or risk issues initially identified in the Risk- Based Prioritizations. Following review of provided information or if adequate relevant information has not been made available, EPA intends to consider whether more concerted voluntary or regulatory actions to require more data or to mitigate the risks for these chemicals may be necessary. As warranted, EPA may nominate some of these chemicals for inclusion in appropriate Federal research or assessment programs, such as the National Toxicology Program (NTP), the Integrated Risk Information System (IRIS), or the National Health and Nutrition Examination Survey (NHANES). EPA also intends to factor in non-domestic data development efforts that are likely to provide needed information (eg., Canadian or European efforts). EPA regulatory actions to address chemicals of special concern might include, where appropriate, the initiation of proceedings for TSCA section 4 test rules or Section 8 rules to collect additional data for chemical assessment; section 6 rules to mandate new labeling requirements or other risk controls; section 5 (a) (2) significant new use rules (SNURS) to ensure notice and limit future risks; or other actions.