With a realization of the widespread potential of exposure in the home, and the special sensitivities of children, comes the realization of the need for adequate assessments of children's exposure in residential environments. Most existing models operate at a low level of detail, do not give sufficient weight to exposure assessment, offer little flexibility, and are much too general to be of great value. The purpose of this dissertation is to introduce the development of new tools for exploring and estimating non-dietary exposure to environmental contaminants.; The first of these tools is the Cumulative and Aggregate Simulation of Exposure (CASE) framework to estimate human exposure from multiple chemicals and through multiple routes. The CASE construct allows for greater control for experimentation, repeatability, and sensitivity analysis, and permits the propagation of variability and uncertainty of input parameters via Monte Carlo simulation. Features of the CASE framework are illustrated in an application to estimate children's residential exposure to lead. Compared to literature values of lead exposure, the CASE framework is capable of producing order of magnitude estimates for the three exposure routes.; Another tool refines dermal exposure estimates by incorporating contact-specific surface area data. The result is a model capable of accounting for spatial characteristics of qualitative hand configurations. An example is given modeling dermal exposure to chlorpyrifos. Such techniques may provide more realistic estimates of concentration gradients across the skin and better representations of dermal exposure due to multiple contacts.; Finally, another module simulates probabilistically relevant sequential micro-level activity data using collected activity patterns. The methods use modified Markov chains to model sequences as a collection of single step transitions. These techniques may aid the field of exposure assessment by extending the value of current sequential micro-level activity data which can be used in intensive model constructs, such as the CASE framework.; Exposure assessment and analysis is a relatively new field. There are many fundamental issues still left to explore. This work has advanced the field of human exposure in a number of ways by both the contributions it makes to the field and the questions that arise in the exploratory process.
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