| Class of Biomarker | Assay | Time Window | Operating Dose Window (Gy, acute photon-equivalent) |
|---|---|---|---|
| Prodromal signs and symptoms | Onset of vomiting | <12 hr | 2–20 |
| Hematological | Depletion of peripheral blood lymphocytes | <1.5 wk | 2–8 |
| Cytological | Lymphocyte-metaphase spread dicentric | < several monthsa | 0.2–5 |
| Lympho cyte-premature chromosome condensation | <several monthsa | 0.2–20 |
a Generally, blood is sampled 24 hours after radiation exposure for cytological chromosome aberration analysis of dose.