What dose range in rems can produce some changes in the blood?

What dose range in rems can produce some changes in the blood?

• A. 5 to 10 rems
• B. 15 to 25 rems
• C. 20 to 60 rems
• D. 25 to 100 rems

Answer: (D)

Radiosensitivity of the blood-forming system means that blood cell counts can show changes even at relatively low radiation doses. Lymphocytes, in particular, are very sensitive to ionizing radiation, so their numbers can drop quickly after exposure and produce measurable hematologic changes. The dose range where these changes begin to appear is about 25 to 100 rems. At the lower end, you may see subtle shifts in blood counts; as the dose moves toward 100 rem, the changes become more noticeable due to greater marrow suppression and effects on circulating cells. Since for gamma/X-rays the rem is effectively the same as the rad, 25 to 100 rems corresponds to roughly 0.25 to 1 Gy, which is sufficient to produce early hematologic changes without immediate signs of radiation sickness.

Radiosensitivity of the blood-forming system means that blood cell counts can show changes even at relatively low radiation doses. Lymphocytes, in particular, are very sensitive to ionizing radiation, so their numbers can drop quickly after exposure and produce measurable hematologic changes. The dose range where these changes begin to appear is about 25 to 100 rems. At the lower end, you may see subtle shifts in blood counts; as the dose moves toward 100 rem, the changes become more noticeable due to greater marrow suppression and effects on circulating cells. Since for gamma/X-rays the rem is effectively the same as the rad, 25 to 100 rems corresponds to roughly 0.25 to 1 Gy, which is sufficient to produce early hematologic changes without immediate signs of radiation sickness.