Uketshezi oluqatha nolumnyama olwenziwa ngokuhlukanisa okubhubhisayo kwamalahle. Luqukethe amakhulu ezinhlanganisela eziphilayo, kuhlanganise ama-phenol, i-naphthalene nama-hydrocarbon e-aromatic anezindingilizi eziningi. Lusetshenziswa njengesivikeli sokhuni (i-creosote), njengesivimbamanzi nangaphambilini njengomthombo wopende owenziwayo nowokuqala kwemithi.