Controlled substances (e.g. narcotics and psychotropics) require
tight security and control. In some countries, scavenging of material from
landfills is a frequent problem, and, disposed drugs may be recovered and sold
by the scavengers. Measures are therefore necessary to prevent diversion during
sorting, and pilfering of drugs from landfills. Immobilization (see Sections 2.3
and 2.4) is the best method of preventing pilfering from a store or landfill.
If, as a last resort, pharmaceuticals must be discarded direct to a landfill
then they must be covered immediately with a large quantity of municipal