Comprehensive Chemical Exposure Framework

Title Page

1.0 Introduction

2.0 Literature Review

3.0 Model Framework

4.0 Scenarios

5.0 Qualitative Analysis

6.0 Recommendations
6.1 Specific Research
6.2 Gap and Sensitivity

7.0 References

Appendix A

6.0 Recommendations for Future Research in Micro-Environmental Modeling

This section of the report provides recommendations for future research priorities based on the design of the CCEF and the current state of the models, databases, and algorithms associated with micro-environmental modeling. These recommendations are specifically based in the design developed in this report for the CCEF and the exposure scenarios and representative compounds defined by the American Chemistry Council for this research. The design of the CCEF allows for detailed computational toxicology, linkages to appropriate databases, and access to sensitivity/gap analyses. The CCEF also facilitates the transformation of the basic science into information that is understandable and directly useable by the decision-maker to scientifically support policy issues.

There is a growing awareness in recent years that a person's exposure to particular chemicals may occur via multiple routes from multiple sources. To adequately evaluate such exposures, the scientific community requires models that can predict the occurrence of exposures for each potential combination of pathway and source and then accumulate these exposures over time. Ideally, the models will account for variations in people's activity patterns that are influenced by age, gender, occupation, and other demographic factors. These activity patterns should realistically simulate the movements of representative people through zones defined by geographic location and microenvironment.

The recommendations for the development of the CCEF are based on the micro-environmental modeling needs of the American Chemistry Council and companies associated with high volume chemicals. They are also based on Battelle's experience in designing, developing, and applying modeling Frameworks for the U.S. Environmental Protection Agency, the U.S. Department of Energy, the U.S. Department of Defense, and the U.S. Nuclear Regulatory Commission. In many cases, Battelle has coordinated development of Frameworks among these different governmental agencies to create a "merged system" that meets the needs of each individual agency but also supports the needs of various modeling types, scopes, scales (both time and space), and resources.

The priority of research conducted by this project is based on the Gap and Qualitative Sensitivity Analyses for each of the four components of the CCEF, which are: Source, Transport, Exposure, and Impacts. A Gap Analysis was conducted for each of these components to identify areas where more than one piece of the modeling puzzle might be missing. This could be a process that requires a model, database, or algorithm that currently does not exist or is in development. A Qualitative Sensitivity Analysis was also conducted on the four components of the CCEF to identify inadequacies in existing models, databases, or algorithms and determine their impact on the overall Framework.