Pesticides in the Diets of Infants and Children (NRC 1993), Science and Judgment in Risk Assessment (NRC 1994), and Understanding Risk: Informing Decisions in a Democratic Society (NRC 1996). In 1997, another expert panel issued its report, Presidential/Congressional Commission on Risk Assessment and Risk Management (PCCRARM 1997).

EPA has also recently upgraded its standards for peer review of technical documents with the Science Policy Council’s Peer Review Handbook (EPA 2000) and guidance (EPA 2002) to conform with the Office of Management and Budget’s Final Information Quality Bulletin for Peer Review (OMB 2004).


As risk assessment has come to be widely used in a fairly consistent framework, EPA practices have continued to draw scrutiny in that competing pressures are pushing the agency to improve the timeliness and quality of its risk assessments. It is now evident that many risk assessments are taking 10-20 years to complete including assessments on chemicals such as dioxin, formaldehyde, and trichloroethylene (GAO 2008). There are a myriad of reasons for delays in the completion of risk assessments including controversy surrounding the science, uncertainties in the data, regulatory requirements, political priorities, and economic factors. In the absence of completed risk assessments, risk management decisions continue to be made by state and federal agencies; however it is not known whether the decisions being made are health protective. To the extent that this practice continues, the value of risk assessment will erode.

For example, trichloroethylene, the most common organic contaminant in groundwater, which has been linked to cancer, does not have a completed EPA toxicity assessment. The EPA assessment has been under development since the 1980s and subjected to multiple independent reviews including EPA’s Science Advisory Board. Key issues were evaluated by the National Research Council in 2006. NRC (2006) urged that the toxicity assessment be finalized with currently available data, but the assessment is not anticipated to be finalized until 2010 (GAO 2008). Another example is formaldehyde, which the World Health Organization classified as a known human carcinogen and whose assessment was begun by EPA in 1997 but is not expected to be completed until 2010 (IARC 2006). The lack of an updated toxicity assessment for formaldehyde has impacted EPA’s regulatory decisions (GAO 2008).2

In recent years, a number of federal agencies have raised concerns about EPA risk assessments of contaminants and are now playing a more formal role in risk policy-making at the federal level. Some of the agencies are also potentially responsible parties facing cleanup responsibilities and are seeking more input as EPA moves toward final reviews. Those other agencies and other public and private stakeholders often assert that they are inadequately involved in EPA processes (for example, Risk Policy Report 2005, 2007).

The Integrated Risk Information System (IRIS) is an important compendium of chemical toxicity values in which new EPA science policies are often implemented for the first time. However, IRIS has been criticized because of limitations, including a lack of funding and delays in updating toxicity values. EPA is now seeking greater science-policy input on its chemical reviews earlier in the process so that critical issues can be identified and adjustments made in response to new scientific and science-policy information.


GAO (2008) acknowledges that because there was no updated EPA cancer risk estimate, EPA’s Office of Air and Radiation used an alternative estimate in establishing a National Emissions Standard for Hazardous Air Pollutants covering facilities in the plywood and composite wood industries.

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