Background: Outpatients treated with low dose radioactive iodine (131I) represent radiation hazard to caregivers and family members. Detailed radiation safety instructions (RSI) should be given by qualified professionals in a clear and proper way to avoid radiation overexposure. We aimed at measurement of cumulative radiation exposure (CRE) to household contacts of outpatients treated with low dose 131I (up to 1110MBq) together with looking for factors that can significantly affect CRE figures.
Methods: Detailed RSI were properly explained to 61 patients and to one or more household contacts (87 out of 296) by radiation safety officer (RSO). Thermo-luminescent dosimeters (TLDs) were dispensed to all contacts after ensuring understanding how and when to be appliedand after confirming that RSI can be conveyed properly to rest of household contacts. TLD's were collected fifth day after dispensing for measurement of CRE figures. The latter were correlated with different patients and contacts factors. Results: CRE figures were well below radiation exposure constraint of caregivers and family members living in the same house with the patient, ranging from 0.071 to 1.026 mSv. Single adult contact had CRE more than 1 mSv and the remaining 295 contacts had CRE below this limit. No single demographic or educational factor had statistically significant correlation with CRE. Lower CRE figures were found for contacts of thyroid cancer patients and contacts who received direct RSI from RSO. Conclusion: All CRE figures of household contacts of outpatients treatedwith low dose 131I therapy were well below radiation exposure constraint, denoting proper compliance of outpatients treated with 131I in King Abdalla Medical City (KAMC) and their household contacts to given RSI.Household contacts of thyroid cancer patients and those who received direct RSI from RSO had relatively lower CRE figures, raising the concept of giving RSI to all household contacts by qualified professionals.