Personal Care Products: Recent studies indicate the presences of a variety of pharmaceuticals and personal care products (PPCPs) in our water.  Because there are thousands of PPCPs in common use, it would be impossible to conduct detailed field and laboratory studies on all compounds of potential concern.  In order to help prioritize research on PPCPs, we developed a system for quantitatively ranking the environmental risks posed by individual PPCPs. This ranking accounts for gross production, human metabolism, removal by sewage treatment, and toxicity to human and ecological receptors. Using this ranking system, we have identified classes of pharmaceutical compounds of highest potential risk.  Interestingly, most of these compounds have never been studied in the environment.  In a follow-up study, we modeled the environmental transport and fate of a subset of these compounds using a multi-compartment box model (BETR-NA) that estimates the distribution of PPCPs between air, water, sediment, and uptake by aquatic biota.  Similarly, we have identified previously unstudied compounds that may be of concern due to their environmental behavior.