42-451 - Definitions LAST AMENDED 6/6/2024 For the purposes of this Section, the following term is defined: Toxic or noxious matter "Toxic or noxious matter" is any solid, liquid, or gaseous matter, including but not limited to gases, vapors, #dusts#, fumes, and mists, containing properties which by chemical means are: (a) inherently harmful and likely to destroy life or impair health; or (b) capable of causing injury to the well-being of persons or damage to property.