We conduct research on trace metal sorption by microbial and 
mineral surfaces, as well as on the formation and reactivity of Mn 
and Fe oxide minerals. Our goal is to understand the interfacial 
processes that determine metal mobility and bioavailability in the 
environment. To this end, we combine environmental chemistry and 
microbiology, X-ray absorption and scattering, electron microscopy, 
and computational geochemistry. Our molecular-scale perspective 
informs models of metal speciation, fate and transport in ecosystems
degraded by mining, industrial activities and non-sustainable 
practices.