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EPA Awards Research Grant to Clark University Grant will help solve mystery between measured biomarkers and chemical exposures

Release Date: 09/27/2007
Contact Information: Paula Ballentine, (617) 918-1027 (EPA New England) Kathleen Deener, (202) 343-9852 (EPA Technical Contact)

(Boston, Mass. - Sept. 27, 2007) - Clark University in Worcester, Mass., just received $677,499 in grant funding from the U.S. Environmental Protection Agency to develop ways to practically use particular kinds of measurements to assess needs for exposure standards to protect against risks of some chemical exposures to pregnant women.

With this grant to Clark, EPA is helping solve the mystery of the connection between measured biomarkers and chemical exposures. A biomarker is a substance, structure, or process that can be measured in biological samples, such as blood or urine, to indicate exposure, susceptibility or health effects. Examples of biomarkers include lead levels in blood or pesticide metabolite levels in urine. Complicating the use of biomarkers to estimate exposures, however, is the fact that different people process and excrete chemicals at different rates. Estimating the extent and implications of this variability requires complex analysis.

These types of biomarkers indicate exposure to specific compounds. In many cases, biomarkers can be measured analytically, but it is not always clear what the levels mean in terms of how much exposure occurred or what amount of the chemical reaches a place in the body where it could possibly cause a health effect (dose).

"This research will help enable EPA scientists protect public and prenatal health by expanding our understanding of what measured biomarker levels mean,” said Robert W. Varney, regional administrator of EPA's New England office.

Clark will work with Columbia University and a toxicologist consultant on this research project. The work follows up on Columbia University’s pioneering research comparing developmental effects in children exposed in the womb to a particular pesticide (chlorpyrifos) before and after it was banned for residential uses. This grant is one of five that EPA is awarding in response to a request for applications called “Interpretation of Biomarkers Using Physiologically Based Pharmacokinetic Modeling."

“Improved estimates of exposure are key to improving the accuracy and relevance of epidemiological studies for assessing health risks,” said Dale Hattis, the Principal Investigator for the grant.

The EPA Science to Achieve Results (STAR) research grant will be used to enhance a computer model that will be able to predict what biomarker levels mean in terms of exposure and dose during pregnancy. The researchers will use chlorpyrifos, an organophosphate (OP) insecticide, as the initial test compound. The research results will allow scientists and risk assessors to understand more about the meaning of biomarkers to help derive a developmental Reference Dose (RfD) and/or Acceptable Daily Intake (ADI).

EPA's STAR program funds research grants and graduate fellowships in many environmental science and engineering disciplines through a competitive solicitation process and independent peer review. The program engages the nation’s best scientists and engineers in targeted research that complements EPA’s own research programs and those of our partners in other federal agencies.

More information: EPA's Science to Achieve Results (STAR) research grants ( epa.gov/ncer )

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