| naturally | 6 | manner |
| throughout the united states | 5 | location |
| from the natural decay of uranium | 5 | cause |
| radon → be found in → water | 26 |
| radon → be present in → water | 13 |
| radon → be released in → water | 8 |
| radon → occur in → ground water | 5 |
| radon → be in → the water | 4 |
| radon → build up in → water | 3 |
| radon → occur in → water | 3 |
| negative | neutral | positive |
| 0.256 | 0.695 | 0.049 |
| Raw frequency | 62 |
| Normalized frequency | 0.607 |
| Modifier score | 0.600 |
| Perplexity | 21.974 |