Superfund Research Program
A Holistochastic Approach to Human Exposure Assessment
Project Leader: George Christakos
Grant Number: P42ES005948
Funding Period: 1995 - 2006
Progress on Project 7 has resulted in advances for the mapping analysis of subsurface environmental contaminants, as well as a novel synthetic paradigm of public health reasoning and epidemic modeling. The environmental contaminant mapping analysis framework was applied to the study of subsurface arsenic in New England, which was part of a student’s PhD dissertation. The first part of this work dealt with the integration of three arsenic datasets collected with substantially different analytical methods, and cross-validation of this work demonstrated that Dr. Christakos and his research team’s framework adequately accounted for the varying levels of measurement error between datasets. The second part of this work dealt with the incorporation of soil-pH as a secondary variable to map subsurface arsenic. The framework the team developed led to a drastic (in excess of 600%) improvement in the efficiency in accounting for the secondary data, leading to subsurface arsenic concentrations that are substantially more accurate than maps obtained with traditional methods (i.e. with a drop of over 50% in the Mean Square Error).The application of the interdisciplinary public health reasoning framework for epidemic modeling was illustrated in a book on the infamous 14th century AD Black Death disaster that killed at least one-fourth of the European population. This book provides insights on potential modern-day pandemics that may have environmental connections, such as the avian flu. The book starts by focusing on the intellectual context in which epidemic research takes place, in a way that accounts for the interdisciplinary and multicultural trends of the emerging Conceptual Age. The authors maintain that for public health scientists to function in an often complex environment, they should be aware of the divergent conceptions of knowledge and the technological changes that these imply, the multiple and often uncertain databases available and their reliability, the different styles of thinking adopted by the disciplines involved, and the importance of developing sound interdisciplinary knowledge integration skills. A unique feature of the book is that it takes the reader through all four major phases of interdisciplinary inquiry: adequate conceptualization (in terms of metaphors, methodological principles, epistemic rules, and argumentation modes), rigorous formulation (involving sophisticated mathematical models), substantive interpretation (in terms of correspondence principles between form and meaning), and innovative implementation (using advanced systems technology and multi-sourced real world databases). Since Black Death had grave societal, public health, and financial effects, its rigorous study can offer valuable insight into these effects, as well as into similar effects that could result from potential contemporary epidemics.