medicine World That Brings the reversal occurred, bringing the levels back up toward their original unhealthy levels. “So, you’re on the freeway surrounded by vehicles with high emissions of pollution— that short-term exposure could impact your As for Dr. Fiedler, her research focused on the effects of pesticides on children. In Thailand, children who live on rice farms are exposed to pesticides daily. Her work— which received a Fogarty International Center R21 grant funded by the National Institute of Environmental Health Sciences— assessed pesticide exposure in that environment by analyzing children who live on the farms, looking in particular for any compromised cognitive and motor functions. Another goal was to help the local university build capacity for doing these types of assessments themselves through the participatory learning experience. The children were tested in three different sessions, and researchers looked at specific urinary biomarkers indicative of pesticide exposure. During the time period, Dr. Fiedler gave seminars and helped to train the university team on the Behavioral Assessment and Research System—a series of computerized tests that can detect cognitive and motor deficits in children exposed to neurotoxic chemicals such as pesticides. The study found that children growing up on rice farms have a significantly higher exposure compared both to those who are reared on shrimp farms in the same Thai community and to children in the United States. In regression analysis, however, the biomarkers of exposure did not predict decrements in cognitive or motor skills. It is important to note that these biomarkers reflected only the prior 24 hours of exposure. There are no good biomarkers to assess longterm exposure, which is the greater concern. “In the United States,” says Dr. Fiedler, “several birth cohort studies have documented effects on cognition that are a result of prenatal exposure, even at lower levels of pesticide exposure than often found in developing countries such as Thailand.” It appears that prenatal exposure may be more relevant for effects on neurodevelopment than exposure during childhood, but this remains to be established. Based on Dr. Fiedler’s experience PHOTOS BY JOHN EMERSON C l o s e r Howard Kipen, MD, MPH (below), professor of environmental and occupational medicine and acting associate director, Environmental and Occupational Health Sciences Institute, was involved in a National Institutes of Health research initiative to study air pollution exposure in Bejing. health right then and there,” explains Dr. Kipen. Since the publication of the study, the doctor’s hope is to continue collaborative efforts such as this one in China, where high pollution levels allow experiments to be done with fewer subjects. Recently, Dr. Kipen and his team were funded for a trial of the effectiveness of air cleaners on indoor air pollution in apartments. 34 Robert Wood Johnson I MEDICINE