Water Use Activities and the Potential Impact on Disinfection Byproduct Mixtures Exposure Assessment

Objective/Intended Use

To develop data and information that can be applied to problems of aggregate exposure and cumulative risk estimation in humans.

Abstract

This effort will build on several completed or existing projects where DBPs have been the primary exposure of interest. Previous epidemiologic results on reproductive or developmental risks that may be associated with consumption of disinfected drinking water are considered equivocal for many reasons. Some of the between-study variability in study findings may be due to unmeasured differences in the type and occurrence levels of mixtures of DBPs and other water exposures. These differences may also be due to incomplete assessment of all likely routes of exposure to humans and reliance on aggregate measures to estimate individual-level exposures. The integration of individual-level data will decrease these exposure uncertainties, aid decision makers in interpreting the results of both epidemiologic and toxicologic studies of waterborne chemical exposures, and will also further develop the scientific approaches for aggregate exposure assessment.

Exposure assessment limitations in environmental epidemiology is a major scientific issue with implications for public health policy. This project will integrate individual-level questionnaire-based information from epidemiologic study settings for different routes of exposure to DBPs. Data on the within- and between-individual variability in water consumption and water-related activities will be used to develop maternal exposure metrics. These exposure metrics may also be used in epidemiologic studies to examine their impact on risk for adverse developmental and reproductive outcomes in humans.

Project Status

The Cooperative Agreement was closed out on October 12, 2005 following receipt of deliverables. Published first manuscript from the Cooperative Agreement in the Journal of Exposure Science and Environmental Epidemiology in 2007. The second manuscript (i.e., the final deliverable) was submitted to the Project Officer and will be submitted to journal in 2008. Additional follow-up research examining the relationship between the blood trihalomethane levels and water use activities is ongoing with collaborators from the CDC, the University of North Carolina and the Mt Sinai School of Medicine.

Expected Completion

The anticipated completion and submission of the final manuscript is 2010. These data and previous research will largely contribute to an EPA report (entitled "Water Use Activities and the Potential Impact on Disinfection Byproduct Mixtures Exposure Assessment") with an expected completion data of 2011.

Project Start Date

09/01/2001

Project Completion Date (Actual/Projected)

12/31/2011