What are listed chemicals in the context of controlled substances?

Listed chemicals refer to substances that are used in the production of illegal drugs, particularly as precursors in the synthesis process. These chemicals are monitored because their legitimate use can contribute to the illegal drug trade. The classification of these substances enables regulatory agencies to track their distribution and prevent misuse, thereby helping to combat drug trafficking and abuse.

In this context, the focus is on their potential illicit applications rather than their benign or cosmetic uses. Other options either suggest that the chemicals have no legitimate uses or imply they are restricted to certain environments like laboratories, which does not reflect the broader regulatory concern around their misuse in drug manufacturing.