| Similarity | Rank | |
|---|---|---|
| aerosols | 0.815 | 54502 |
| gases | 0.797 | 11662 |
| dioxide | 0.796 | 10273 |
| pollutants | 0.786 | 16074 |
| pollutant | 0.775 | 41997 |
| contaminant | 0.774 | 45441 |
| particulates | 0.771 | 55487 |
| troposphere | 0.767 | 92087 |
| chlorine | 0.764 | 17545 |
| ionization | 0.764 | 60226 |
| gasses | 0.762 | 45276 |
| ionizing | 0.757 | 62668 |
| CO2 | 0.755 | 9992 |
| aerosol | 0.755 | 34492 |
| sulfur | 0.754 | 22001 |
| nitrogen | 0.751 | 12237 |
| particulate | 0.750 | 32316 |
| radioactivity | 0.749 | 42842 |
| gaseous | 0.747 | 42339 |
| methane | 0.747 | 19799 |
| dioxin | 0.746 | 57731 |
| NOx | 0.746 | 55787 |
| radon | 0.745 | 32433 |
| dioxins | 0.743 | 77636 |
| SO2 | 0.743 | 90224 |