sulphur dioxide | 2.76 | Lead, carbon dioxide and sulphur dioxide in the air are down. | ||
sulphur emission | 1.25 | The report recommends a threefold cut in sulphur emissions. | ||
sulphur content | 1.18 | The water has a high sulphur content. | ||
sulphur level | 0.33 | This includes measures to introduce lead-free petrol, and reduce sulphur levels in both petrol and diesel. | ||
sulphur compound | 0.26 | The landscape is a stony desert, smeared here and there with sulphur compounds. |