DNA damage Evaluation in a Nursing Team Occupationally Exposed to Ionizing Radiation

Abstract

Purpose : To evaluate DNA damage in lymphocytes and cognitive deficits in a nursing team occupationally exposed to ionizing radiation in a university hospital in southern Brazil. Method : Cross-sectional study, case-control design, included 79 women working in a nursing team in Hemodynamics, Radiology, Ambulatory and Midwifery Units. They were classified in two groups: 1_Exposed to ionizing radiation, n=38 (Hemodynamics and Radiology Units) and 2_Unexposed to ionizing radiation, n=41 (Ambulatory and Midwifery Unit). Blood was collected and DNA damage in lymphocytes was analyzed using the comet assay and micronucleus test (MN). The cells were classified according to the damage frequency (DF) and index (DI) based on the comet tail size. Cognition was also evaluated according to the scores obtained in Stroop test, the digit and word span. Results : No difference was found for the variables DI, DF, MN, Stroop_word, Stroop_color, Stroop_color/word between the groups. However, when the groups were analyzed independently of their exposure condition, the damage index in the Hemodynamics was lower than in all other Units. The damage frequency in Midwifery Unit was higher than in Ambulatory and Hemodynamics. The frequency of micronucleus was not different among the employees from the four Units. Conclusions : DNA damage in lymphocytes did not differ between nursing teams occupationally exposed or not exposed to ionizing radiation. However, higher damage in a non exposed group may indicate other risks to the healthcare team.