US EPA

The EPA identifies the components of a chemical risk assessment as the hazard identification, dose-response, and exposure assessments that are then integrated into a risk characterization. Of the three, the exposure assessment is the most important in influencing the risk characterization since exposures can be controlled, whereas the hazard identification and dose-response assessments describe inherent features of the agent.

In order to promote consistency and transparency in EPA risk assessments, the Agency produces guidance that articulates the current state-of-the-practice at EPA. The current guidance document for human exposure assessment, Guidelines for Exposure Assessment, was published in 1992, reflecting the state-of-the-science in the 1970s and 1980s. Since its publication, the field of exposure science has undergone significant transformation in methods and approaches. EPA programs have incorporated many of these advances into their policies and practices. Accordingly, the exposure guidelines are being revised and updated to reflect these changes.

The Peer Review Draft – Guidelines for Human Exposure Assessment (2016), benefits from over two decades of experience with EPA assessments conducted by Agency programs under their respective authorities and constraints, and input from external panels, including the National Academies of Sciences and EPA’s Science Advisory Board. These new draft guidelines extend topics covered in the 1992 exposure guidelines including planning and scoping for an assessment, data acquisition and use, modeling, and consideration of uncertainty. In addition, it includes new material on planning and conducting an observational human exposure measurement study and considerations of lifestages and sensitive populations in exposure assessments. The draft guidelines present the most current science used in EPA exposure assessments and incorporates the Agency’s current policies.

The U.S. Environmental Protection Agency's (EPA's) Exposure Assessment Guidelines (EAGLs) are designed to identify principles and procedures used by EPA scientists in the conduct of Agency risk assessments. They outline the limits of sound scientific practice, reference approaches and tools for exposure assessment and their appropriate use, and emphasize the scientific basis and rationale for each assessment, including identification of uncertainties, assumptions, and limitations. Numerous advances in the science of exposure assessment since the Guidelines were developed in 1992, in such areas as probabilistic analyses, human activity factors, and consideration of susceptible populations and life stages, encourage their revision.

Examples of advances include such areas as probabilistic analyses, human activity factors, and consideration of susceptible populations and life stages. The Risk Assessment Forum (RAF) gathered input from internal and external stakeholders via a series of meetings and colloquia. A panel of experts at the International Society for Exposure Analysis in November 2005 provided comments on the proposed plan of revision. The White House Council on Environment and Natural Resources (CENR) was briefed in spring 2006, and an interagency group consisting of senior federal scientists was also briefed due to the high level of interest in the project. In 2008, a draft final version will be provided to the Science Advisory Board for review and consultation.

Update the guidelines to address current, new, and emerging science and related assessment methodologies