Screening Level Tools
Screening Level Tools are developed to be easy to use, fast and conservative. These tools are often used in the absence of appropriate monitoring data or to compliment exposure related data. They are designed to quickly "bin" chemicals by priority for future work and are commonly used in screening level risk assessments. Screening Level Tools include Chemical Screening Tool for Exposures and Environmental Releases (ChemSTEER), Estimation Program Interface Suite (EPI Suite), Exposure and Fate Assessment Screening Tool (E-FAST), Pesticide Inert Risk Assessment Tool (PIRAT), and ReachScan. These tools have the following characteristics:
Require Minimal Data Entry: A challenging aspect of exposure assessment is finding exposure factor values that are truly representative of the exposure a user is evaluating. Using readily available data and standard (i.e., default) exposure factors can be a helpful time saver and enable consistent comparisons of exposures. All of the Screening Level Tools include default values which can be changed by the user. The standard default values were carefully selected, often from Agency guidance documents, and their impact on the results has been characterized and described in the model or accompanying documentation. If the default values are used, the descriptive language should be included in the results. If other values are used, they should be carefully selected, and their impact evaluated and described in the results. The default values are general in nature, and you may find it helpful to use more specific exposure-related data.
Quickly Screen Exposure Concerns: Because these models have minimal data entry and are pre-loaded with many default values, these tools can be quickly applied to exposure assessment scenarios.
Create Conservative Estimates of Exposure. These tools were designed for exposure screening activities and therefore err on the side of safety (i.e., they estimate high or perhaps higher than actual values of exposure). These artificially high estimates mean that some substances will have exposure concerns where there actually are none; however, this bias provides a level of confidence that substances with exposure estimates indicating no concern are in fact not a concern.
These models are included within U.S. EPA's Sustainable Futures. Sustainable Futures couples these exposure tools with screening level hazard tools, and provides technical assistance to companies interested in using the tools. To date, the response from industry has been very positive, and companies have begun using the tools to design and manufacture safer products while improving the research and development efficiency.