| ACIDRAIN | What is rainfall polluted by atmospheric sulphur and nitrogen oxides? (4,4) |
| NOXIOUS | Nitrogen oxide? Independent forums regularly say it's harmful |
| INERTGAS | Granite's polluted by helium, eg (5,3) |
| LEACHATE | Water polluted by percolation through solid matter, as in landfill sites (8) |
| ILMENITE | Black mineral composed of oxides of iron and titanium (8) |
| MAJOLICA | A porous pottery glazed with bright metallic oxides, originally imported into Italy and later made there (8) |
| AGASAGAS | These novels are great fun on nitrous oxide? |
| POSITION | Put sulphur and iodine in possibly toxic brew |
| DISCLOSE | Let drop when draught contains iodine, sulphur and chlorine (8) |
| SCRUBBER | It purifies sulphur and carbon connected to tyre (8) |
| GENERALS | Widespread sulphur and brass (8) |
| METAL | Any of a class of chemical elements usually lustrous ductile solids and good conductors of heat and electricity and forming basic oxides |
| ALUMINA | What is an alternative name for aluminium oxide? (7) |
| ACETYLENE | Great river polluted by drops of liquid ethyne? Just so |
| SMOKY | Like air that has been polluted by cigarettes |
| AIRBASE | Atmosphere polluted - by flying actively here? (3,4) |
| OCHRE | Earthy mineral oxides or iron mingled with amounts of clay and sand (5) |
| MIASMAL | Back strike's target, what's caused by atmospheric pollution (7) |
| MIRAGE | Illusion caused by atmospheric refraction by hot air (6) |
| MIRAGES | Images of distant objects, often inverted or distorted, caused by atmospheric refraction by hot air (7) |
