Final answer:
Not all pharmacies are equipped to destroy controlled substances on-site; this process is heavily regulated to prevent environmental contamination and improper use, with high-temperature incineration being a common method when allowed.
Step-by-step explanation:
Not all pharmacies are equipped or legally permitted to destroy controlled substances on-site. The process for the disposal of controlled substances is highly regulated to prevent environmental contamination and improper use. Pharmacies are required to follow strict guidelines laid out by regulatory bodies, such as the DEA in the United States. These regulations ensure that pharmaceutical residues are disposed of in a manner that does not leave ecotoxic activity or contribute to the environmental formation of new hazardous substances.
High-temperature incineration is one of the methods that meet these strict requirements, with temperatures exceeding 1000 degrees Celsius being capable of effectively breaking down most pharmaceutical compounds. Even after such incineration, the residual ashes must be handled properly to avoid any risk of contamination.