The detection of pharmaceutical chemicals in the environment is viewed with concern because of their biological activity, although thus far no measurable risks to human health have been demonstrated from their presence in the environment. The particulate nature of pharmaceutical chemicals, especially solid and semisolid dosage forms, has received considerable attention from the point of view of raw material and finished product quality, but little attention from the point of view of their ecosystem effects. Therefore, research in support of the interaction of particulate pharmaceuticals and environmental matrices is much needed. The current state of understanding on this subject is summarized in this review with discussions on life cycle of pharmaceutical drugs, pharmaceutical supply chain management activities on waste minimization, and potential environmental exposure during manufacture, use, and disposal. The distribution, dilution, and degradation in various environmental matrices are explained and illustrated in flowcharts.