Superfund Research Program
A Holistochastic Approach to Human Exposure Assessment
Project Leader: George Christakos
Grant Number: P42ES005948
Funding Period: 1995 - 2006
Dr. Christakos' team has demonstrated the importance of the composite space-time analysis of human exposure, and the crucial role that the integration of theoretical with environmental sciences can play in modern risk assessment. They have shown that an environmental health analysis based on the conceptual blending of knowledge bases from different scientific disciplines (physical, biological, epidemiological, etc.), all relevant to the human exposure problem under consideration, can lead to much better predictions of health effects across space-time and to a more rigorous and informative risk assessment than an analysis based solely on epidemiological investigations. Project investigators have emphasized the critical effects of natural variability and human uncertainty sources across space-time in gaining a deeper understanding and deriving a mathematically rigorous and scientifically meaningful description of exposure-health effect associations in a stochastic context. The holistochastic human exposure framework (HHEF) pioneered by this group for this purpose has gained considerable international recognition as an efficient, flexible and general TGIS-based modeling tool for science-based human exposure analysis and risk assessment. It is currently used by many scientists and researchers in sixteen countries. As a result, these efforts have a significant influence on modern environmental health research and development worldwide. Several of the case studies completed in the last few years [Cherry Point (NC, USA), Bangladesh, Chernobyl (Russia), California (USA)] were original from a methodological viewpoint, and they amply demonstrated the wide applicability of the HHEF approach in realistic human exposure situations.