Table 1. Bone marrow PCE/NCE ratios in mice exposed to low doses of tritium in drinking water and to external γ-irradiation for 1 or 8 months.
| Treatment group | No of mice | PCE/NCE* | PCE/NCE S.E.M |
|---|---|---|---|
| 1 month | |||
| Control | 10 | 1.08 | 0.10 |
| HTO 10 kBq/L | 10 | 1.12 | 0.08 |
| HTO 1 MBq/L | 10 | 0.98 | 0.07 |
| HTO 20 MBq/L | 10 | 1.05 | 0.08 |
| OBT 10 kBq/L | 10 | 1.04 | 0.06 |
| OBT 1 MBq/L | 10 | 1.11 | 0.09 |
| OBT 20 MBq/L | 10 | 1.07 | 0.08 |
| Gamma 1.44 μGy/h | 12 | 1.02 | 0.05 |
| Gamma 31.0 μGy/h | 12 | 1.04 | 0.06 |
| 8 months | |||
| Control | 10 | 0.97 | 0.12 |
| HTO 10 kBq/L | 9 | 1.01 | 0.09 |
| HTO 1 MBq/L | 12 | 0.97 | 0.09 |
| HTO 20 MBq/L | 12 | 0.93 | 0.07 |
| OBT 10 kBq/L | 10 | 1.11 | 0.11 |
| OBT 1 MBq/L | 10 | 0.99 | 0.09 |
| OBT 20 MBq/L | 10 | 1.01 | 0.12 |
| Gamma 1.44 μGy/h | 10 | 0.97 | 0.07 |
| Gamma 31.0 μGy/h | 10 | 0.96 | 0.09 |
*None of the changes in treatment groups were statistically significant compared to corresponding control (Student's t-test).