In radiation protection, the effective dose (in Sieverts) is calculated to compare radiation risks from different exposures and different body parts. The organ weighting factor (wT) for the gonads in the ICRP 103 (2007) recommendations is:
- A 0.20 (highest weighting, as in ICRP 60)
- B 0.01 (lowest, along with skin and bone surface)
- C 0.08 (same as lung and stomach, no longer highest-weighted organ) ✓
- D 0.12 (same as colon and bone marrow)
Correct answer: C. 0.08 (same as lung and stomach, no longer highest-weighted organ)
Explanation
In ICRP 103 (2007), the tissue weighting factor (wT) for gonads was reduced from 0.20 (ICRP 60, 1990) to 0.08, equal to lung, stomach, colon, and bone marrow — reflecting revised cancer risk and hereditary effect data. The highest-weighted tissues in ICRP 103 are lung, stomach, colon, bone marrow, and breast (each 0.12), not the gonads. This change has implications for calculating effective dose from pelvic CT examinations.
Reference: Grainger & Allison's Diagnostic Radiology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.