Table 1.
The values of mass density (ρ) and effective atomic number (Z)a for 34 ICRU-44 tissues. Tissue used in the 4-tissue and 8-tissue small animal dose calculations are italicized.
| Medium | P g∕cm3 | Z |
|---|---|---|
| Lung (inf.) | 0.260 | 7.879 |
| Adipose | 0.950 | 6.670 |
| Skeleton-yellow marrow | 0.980 | 6.559 |
| Cell nucleus | 1.000 | 8.167 |
| Breast | 1.020 | 7.271 |
| Skeleton-red marrow | 1.030 | 7.266 |
| GI tract | 1.030 | 7.710 |
| Lymph | 1.030 | 7.837 |
| Pancreas | 1.040 | 7.699 |
| Testis | 1.040 | 7.816 |
| Brain | 1.040 | 7.878 |
| Thyroid | 1.050 | 7.710 |
| Ovary | 1.050 | 7.843 |
| Muscle | 1.050 | 7.848 |
| Kidney | 1.050 | 7.840 |
| Lung (def.) | 1.050 | 7.879 |
| Heart | 1.060 | 7.806 |
| Blood | 1.060 | 7.825 |
| Liver | 1.060 | 7.866 |
| Spleen | 1.060 | 7.872 |
| Eye lens | 1.070 | 7.541 |
| Skin | 1.090 | 7.627 |
| Skeleton-cartilage | 1.100 | 8.329 |
| Skeleton-spongiosa | 1.180 | 10.678 |
| Skeleton-sacrum | 1.290 | 11.407 |
| Skeleton-vert. column (D6,L3) | 1.330 | 11.742 |
| Skeleton-femur | 1.330 | 12.087 |
| Skeleton-ribs (2,6) | 1.410 | 12.224 |
| Skeleton-vert. column (C4) | 1.420 | 12.271 |
| Skeleton-humerus | 1.460 | 12.612 |
| Skeleton-ribs (10) | 1.520 | 12.760 |
| Skeleton-cranium | 1.610 | 13.129 |
| Skeleton-mandible | 1.680 | 13.332 |
| Skeleton-cortical bone | 1.920 | 13.978 |
a
Z, where wi is fraction by weight of element i with atomic number 22 Zi22 (Ref. 22).