Peggy O'Day Research Group

University of California, Merced

A contaminant’s chemical form helps determine where it travels and how it affects living systems. Peggy O’Day studies metals and metalloids in surface and subsurface environments, using spectroscopy and microscopy, particularly synchrotron X-ray methods, to identify molecular reaction mechanisms. Her research combines these observations with thermodynamic, kinetic, and reactive-transport models. Projects include mercury chemistry, mineral surfaces, airborne particles, uranium reactions, and soil remediation. The work connects molecular-scale geochemistry with environmental transport, bioavailability, and approaches to managing contaminated soils and sediments.