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Last Edited: 5/11/2005

Childhood Cancer - Etiologic Clues Using Geographic Information Systems
09/1991 - 09/2003

Little is known about the causes of  childhood cancers, but there has been increasing public concern that environmental toxicants may contribute to the risk of developing this heterogeneous group of diseases.  California, with the largest population-based cancer registry in the world and with a unique wealth of environmental exposure databases, provides an unusual opportunity to evaluate these rare malignancies in geographically and socio-culturally diverse settings.

This study evaluated the first five years (1988-1992) of California statwide population-based chilhood cancer incidence data together with geographic indicators of the soicio-cultural diversity of the state and in conjunction with well characterized and temporally relevant detailed statewide environmental exposure information, it explored some of  the more prominent current hypotheses about environmental influences on the eitiology of these diseases.  This work builds on the California Department of Health services, Environmental Health Investigation Branch's long history of work in the study of childhood cancer "clusters," in characterizing environmental exposures of concern to human health and in developing geographic information system (GIS) analysis strategies to complement epidemiologic research efforts.

The study's specific aims were targeted at an evaluation of how childhood cancer rates vary with geographically defined environmental emissions or exposures, how childhood cancer rates vary by demographic characteristics of the population, and  the independent effects of environmental or demographic risk associations.

The study was designed to identify risk associations worthy of more in-depth investigations, while minimizing some of the limitations of ecologic research.  Significantly, the availabilitity of unique existing databases to characterize both exposure and disease outcome in California's large and heterogeneous population offer an opportunity to integrate epidemiologic, environmental exposure, and GIS analytic strategies to enhance our understanding of factors influencing a group of rare diseases with consititue a major cause of death in children.