Occupation radiation exposure on radiographers and radiologists: levels and risks at University of Teaching Hospital and cancer disease hospital, Lusaka Zamba

Abstract

Radiation exposure and its potential complications is one of the most important issues in occupational health. Implementation of proper occupational health system may have an important bearing not only on the health of the population occupationally exposed to radiation but also on the health and prosperity of the community. The study aimed at analysing the radiation dose received by workers and assessing their perceptions about their exposure. The study used embedded mixed methods design. Doses for Radiographers, Radiologists, Medical Physists and Nurses working at Cancer Disease Hospital (CDH) and University Teaching Hospital (UTH) were analysed. Thermoluminescent dosimeters (TLD) were used to review radiation doses over a 3-year period (2013-2015. Random effect linear regression model was used to identify potential risk factors of radiation dose. Key informant interviews and semi structured questionnaire were conducted at both sites. There were 55 records from UTH and 43 from CDH for the quantitative part. For the qualitative part, there were 16 respondents 14 from UTH and 2 key informants from CDH and UTH. About 5.3% of the radiations doses were above the 1.2mSv lower monthly monitoring level. Being female (p-value 0.035) and being at UTH (p-value 0.041) was associated with higher radiation dose. UTH had a mean dose of 0.69 mSv, SD 0.9 (95% CI =0.47- 0.78) and this was higher than CDH which had mean dose of 0.46mSv, SD 0.3 (95% CI= 0.25 -0.364) over the period under review. When the dose exposure was stratified according to sex, women had a higher mean dose of 0.46 mSv (SD 0.3) than Men who had 0.69 mSv (SD 0.4 P-value=0.012.) Majority of the workers thought that they were being overexposed to radiation. They cited a number of factors that they thought were contributing to these levels including, state of equipment, and human factors. Occupation radiation exposure at UTH and CDH were found to be within monitoring limits. However about 5.3% of radiation doses were above the 1.2 mSv lower monthly monitoring level. There is need for continued education and training of personnel in principles of radiological protection as well as strengthening the monitoring system.