Controlled substance designation for listed precursor chemicals expands regulatory control to curb their use in illicit drug manufacture. Declaration under clause (viid) of section 2 of the Narcotic Drugs and Psychotropic Substances Act, 1985, designating specified chemicals and preparations as controlled substances because of their potential use in producing narcotic drugs and psychotropic substances and to implement the 1988 UN Convention. A Table lists fourteen substances and categories including alkaloids, precursor ketones, aromatic intermediates, oxidising agents and preparations of ephedrine and pseudoephedrine, thereby subjecting those listed items to the statutory controlled-substance regime.