Unused pharmaceuticals take an unhealthy toll on both the environment and human health. In the US alone, an estimated {dollar}1 billion of prescription drugs are thrown away each year. Increasing availability, marketing, and purchasing of both prescription and over-the-counter medications, coupled with the tendency of patients to discontinue use of and to stockpile drugs at home, is a unique problem that has garnered increasing attention among scientists, policymakers, and the media in the last ten years; These accumulated household drugs become unused pharmaceutical waste. This waste must be discarded and disposed of by the consumer. Historically, consumers have been instructed by health care professionals to dispose of unwanted medications into the sewage system. Inserts in some pharmaceutical packaging have also instructed consumer to flush expired and unused medications down the toilet. This method has historically also applied to pharmaceuticals stored in locations other than the consumer household; In the past decade studies have consistently identified amounts of pharmaceutical residues in water systems throughout the country. However, it has yet to be determined if the source of these substances found in the waterways is from excretion or disposal. While it is most likely a combination of both, it has been difficult to assess to what extent disposal takes place. Namely, there has been no source of data that would convey how often disposal takes place, what are the more common pharmaceutical compounds disposed, and in what quantities these compounds are flushed into our sewage systems; This dissertation describes a new methodology---compiling inventory data from coroner offices---which can provide a source of data detailing exactly how much of a specific pharmaceutical ingredient has been disposed in a particular geographic area and the frequency with which that compound is found in the disposal inventories. Further, this work assesses the many, varied, and often overlooked sites of accumulation of unused medications, the approximate relative contributions generated at each site, and common reasons why they accumulate in their respective locations. Finally, this work assesses the risk associated with inappropriate transfers of pharmaceuticals, and potential means for mitigating the risks
