EPA  assesses the human health risks of chemicals using a model from the  National Academies. Taken together, these two steps are commonly referred to as IRIS toxicity  assessments. California Environmental Protection Agency (Cal/EPA) Toxicity  Assessments. Without a clear understanding of current demand for IRIS toxicity  assessments, EPA cannot adequately measure the program’s  performance; effectively determine the number of IRIS assessments  required to meet the statutory, regulatory, and programmatic needs of  IRIS users; or know the extent to which unmet demand exists. According to the report, EPA estimated that 50 new or updated IRIS  toxicity assessments a year were needed to meet user needs. However, based on our review of the report, we did not  find sufficient support for the estimate. EPA’s Chemical Nomination and Selection Process May Not Accurately Reflect Current Demand for IRIS Toxicity Assessments

The IRIS Program’s chemical nomination and selection process, which  the agency uses to gauge interest in the IRIS Program from users inside  and outside of EPA, may not accurately reflect current demand for IRIS  toxicity assessments. Also, given the long-standing challenges the IRIS Program has had in  routinely starting new assessments, according to some EPA IRIS users,  they chose not to nominate new chemicals for assessment and instead  nominated chemicals that were already listed on the IRIS agenda as  under way. Consequently, for the chemicals that were nominated  during the most recent 2011 nomination period, but not selected, it is not  clear how many, if any, were excluded from consideration because they  did not meet the IRIS Program’s selection criteria, because the IRIS  Program determined that an IRIS toxicity assessment was not needed— or, alternatively, if they were not selected because of resource constraints  or other reasons. EPA Has Not Implemented an Agencywide Strategy for Addressing Unmet Needs for IRIS Toxicity Assessments

EPA has not implemented an agencywide strategy for addressing the  unmet needs of EPA program offices and regions when IRIS toxicity  assessments are not available, applicable, or current. Specifically, EPA  does not have (1) a strategy for identifying and filling data gaps that would  enable it to conduct IRIS toxicity assessments for nominated chemicals  that were not selected for IRIS toxicity assessment due to insufficient data  and (2) agencywide guidance for addressing unmet needs when IRIS  toxicity assessments are not available, applicable, or current—which is  consistent with findings reported recently by EPA’s Inspector General and  Science Advisory Board. EPA has not evaluated demand for IRIS toxicity  assessments with input from users inside and outside the agency since  2003, and although IRIS Program officials recognize that the 2003  estimate does not reflect current conditions, the agency does not plan to  perform another evaluation of demand. Furthermore,  EPA has not clearly articulated how the IRIS Program applies the criteria  it uses to prioritize the selection of chemicals for IRIS toxicity  assessment—including how it determines the circumstances under which  program offices and regions may or may not need an IRIS toxicity  assessment. To ensure that EPA maximizes its limited resources and addresses the  statutory, regulatory, and programmatic needs of EPA program offices  and regions when IRIS toxicity assessments are not available, we  recommend that the EPA Administrator direct the Deputy Administrator, in  coordination with EPA’s Science Advisor, to implement the following  action:
Once demand for the IRIS Program is determined, develop an  agencywide strategy to address the unmet needs of EPA program  offices and regions that includes, at a minimum:  coordination across EPA offices and with other federal research  agencies to help identify and fill data gaps that preclude the  agency from conducting IRIS toxicity assessments, and guidance that describes alternative sources of toxicity information  and when it would be appropriate to use them when IRIS values  are not available, applicable, or current. Specifically, EPA agreed with our recommendations that the Office of  Research and Development (1) identify and evaluate demand for the IRIS  Program to determine the number of IRIS toxicity assessments and  resources required to meet users’ needs and (2) document how EPA  applies its IRIS toxicity assessment selection criteria, including the  circumstances under which program offices and regions may or may not  need an IRIS toxicity assessment. In the absence of  agencywide guidance that addresses unmet demand for IRIS  assessments, EPA offices operate in much the same way they operated  before the IRIS Program was formed to develop consensus opinions  within the agency about the health effects from chronic exposure to  chemicals. We did not evaluate the scientific content or quality of  IRIS toxicity assessments. 3.
Why GAO Did This Study

EPA created the IRIS database in 1985 to help develop consensus opinions within the agency about the health effects from chronic exposure to chemicals. The health effects information in IRIS--referred to as IRIS toxicity assessments--provides fundamental scientific information EPA needs to develop human health risk assessments. GAO was asked to review the effectiveness of EPA's implementation of its IRIS toxicity assessment process. This report determines the extent to which (1) EPA has evaluated demand for IRIS toxicity assessments from users inside and outside EPA; (2) EPA's process for nominating and selecting chemicals for IRIS toxicity assessment accurately reflects demand; and (3) EPA has implemented a strategy for addressing any unmet agency needs when IRIS toxicity assessments are not available, applicable, or current. To do this work, GAO reviewed and analyzed IRIS nomination data, among other things, and interviewed EPA officials. GAO did not evaluate the scientific content or quality of IRIS toxicity assessments.

What GAO Found

The Environmental Protection Agency (EPA) has not conducted a recent evaluation of demand for Integrated Risk Information System (IRIS) toxicity assessments with input from users inside and outside EPA. Specifically, EPA issued a needs assessment report in 2003, which estimated that 50 new or updated IRIS toxicity assessments were needed each year to meet users' needs. However, GAO did not find sufficient support for the estimate. In addition, IRIS Program officials recognize that the 2003 estimate does not reflect current conditions, but the agency does not plan to perform another evaluation of demand. Without a clear understanding of current demand for IRIS toxicity assessments, EPA cannot adequately measure the program's performance; effectively determine the number of IRIS toxicity assessments required to meet the needs of IRIS users; or know the extent of unmet demand.
The IRIS Program's chemical nomination and selection process, which the agency uses to gauge interest in the IRIS Program from users inside and outside of EPA, may not accurately reflect current demand for IRIS toxicity assessments. The 75 chemicals that were nominated in response to EPA's most recent 2011 nomination period may not reflect demand for a number of reasons. For example, given the long-standing challenges the IRIS Program has had in routinely starting new assessments, according to some EPA IRIS users, they chose not to nominate new chemicals for assessment. Also, EPA has not clearly articulated how the IRIS Program applies the criteria it uses to prioritize the selection of chemicals for IRIS toxicity assessment--including how it determines the circumstances under which an IRIS toxicity assessment is or is not needed. Consequently, for chemicals that were nominated but not selected for assessment, it is not clear how many, if any, were excluded from consideration because they did not meet the IRIS Program's selection criteria because the IRIS Program determined that an IRIS toxicity assessment was not needed--or, alternatively, if they were not selected due to resource constraints or other reasons.
EPA has not implemented an agencywide strategy for addressing the unmet needs of EPA program offices and regions when IRIS toxicity assessments are not available, applicable, or current. Specifically, EPA does not have a strategy for identifying and filling data gaps that would enable it to conduct IRIS toxicity assessments for nominated chemicals that are not selected for assessment because sufficient data from health studies are not available. IRIS Program officials stated that no agencywide mechanism exists for EPA to ensure that chemicals without sufficient scientific data during one nomination period will have such information by the next nomination period or even the one after that. These officials acknowledged that better coordination across EPA and with other federal agencies could help address the issue. EPA also does not have agencywide guidance for addressing unmet needs when IRIS toxicity assessments are not available, applicable, or current. In the absence of agencywide guidance, officials from select EPA offices stated that they used a variety of alternatives to IRIS toxicity assessments to meet their needs, including using toxicity information from other EPA offices or other federal agencies.

What GAO Recommends

GAO recommends that EPA evaluate demand for IRIS assessments; document how the agency applies its selection criteria, including the circumstances under which an IRIS toxicity assessment is or is not needed and; develop an agencywide strategy including, at a minimum, coordination across EPA offices, as well as with other federal agencies, to identify and fill data gaps, and providing guidance that describes alternative sources of toxicity information. EPA agreed with the first two recommendations and partially agreed with the third.