Orphans of the Lab University laboratories are dynamic places. Professors retire, employees get promoted, and graduate students move on. Chemicals left undisposed are often poorly labeled and can present a safety hazard to the people who eventually do the cleanup. And cleanup can be years or sometimes even decades later. Unlabeled chemicals must be characterized to ensure responsible disposal.
Unknowns also eliminate opportunities for redistribution or other kinds of recycling.
The person most directly involved in using the material should arrange for disposal, as they are the most knowledgeable about uses. This approach usually results in the most economical disposal. In addition, good chemical management is essential. This includes good housekeeping, careful purchasing and inventory control and unambiguous labeling of all containers. A good practice used in several laboratories on campus is the initialing and dating of chemical containers when opened or received.