air impurities "air impurities" includes smoke, soot, dust, ash (including flyash), cinders, grit, solid particles of any kind inclusive of particulates, gases, fumes, mist, odours and radioactive substance which are generated as a result of combustion of fuel and the like, or a result of the use of electricity as a heat source, or a result of synthesis, resolution or any other treatment and any other substance which may be designated by the Minister as those which are liable to affect adversely the human health or the living environment; PU(A) 280/1978 - ENVIRONMENTAL QUALITY (CLEAN AIR) REGULATIONS, 1978 2. Interpretation.