| Similarity | Rank | |
|---|---|---|
| pollution | 0.831 | 2289 |
| toxic | 0.811 | 5194 |
| sulphur | 0.801 | 6647 |
| emission | 0.792 | 3620 |
| nox | 0.784 | 28969 |
| chlorine | 0.780 | 10537 |
| dioxide | 0.778 | 4762 |
| methane | 0.773 | 11786 |
| dioxin | 0.772 | 17452 |
| contaminant | 0.769 | 23773 |
| monoxide | 0.769 | 12904 |
| halon | 0.769 | 27495 |
| lindane | 0.765 | 67136 |
| nitrogen | 0.764 | 6386 |
| groundwater | 0.760 | 12650 |
| particulate | 0.756 | 25930 |
| pollute | 0.756 | 9638 |
| nitrate | 0.755 | 7756 |
| smog | 0.755 | 16818 |
| tetrachloride | 0.754 | 38419 |
| contamination | 0.752 | 7877 |
| chlorinate | 0.752 | 31192 |
| hydrocarbon | 0.751 | 12320 |
| carcinogen | 0.751 | 23531 |
| hcfc | 0.747 | 89263 |