title: Redox status in workers occupationally exposed to long-term low levels of ionizing radiation: A pilot study.
abstract: OBJECTIVE
  Reactive oxygen species (ROS), including superoxide (O2(•-)), play an important role in the biological effects of ionizing radiation. The human body has developed different antioxidant systems to defend against excessive levels of ROS. The aim of the present study is to investigate the redox status changes in the blood of radiologic technologists and compare these changes to control individuals.
  
  
  METHODS
  We enrolled 60 medical workers: 20 occupationally exposed to ionizing radiation (all radiologic technologists), divided in three subgroups: conventional radiography (CR), computerized tomography (CT), and interventional radiography (IR) and 40 age- and gender-matched unexposed controls. Levels of O2(•-) and malondialdehyde (MDA) in blood were measured as an index of redox status, as were the activities of antioxidant enzymes superoxide dismutase (SOD) and catalase. Redox status was also assessed by measuring levels of reduced and oxidized glutathione (GSH, GSSG, respectively).
  
  
  RESULTS
  Levels of O2(•-) and MDA, and SOD activity in the blood of IR and CT-exposed subjects were significantly higher than both the CR-exposed subjects and control individuals. However, there were no statistically significant differences in the levels of catalase, GSH and ratio of GSH/GSSG between exposed workers and control individuals.
  
  
  CONCLUSIONS
  This study suggests that healthcare workers in CT and IR occupationally exposed to radiation have an elevated circulating redox status as compared to unexposed individuals.
authors.affiliation: a Radiation Science Technology Education, College of Allied Health Professions , University of Nebraska Medical Center , Omaha , USA.
authors.forename: Iman M
authors.initials: IM
authors.lastname: Ahmad
authors.affiliation: a Radiation Science Technology Education, College of Allied Health Professions , University of Nebraska Medical Center , Omaha , USA.
authors.forename: James B
authors.initials: JB
authors.lastname: Temme
authors.affiliation: b Department of Pathology and Microbiology , University of Nebraska Medical Center , Omaha , USA.
authors.forename: Maher Y
authors.initials: MY
authors.lastname: Abdalla
authors.affiliation: c Department of Cellular and Integrative Physiology , University of Nebraska Medical Center , Omaha , USA.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Zimmerman
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D005260:Female; D005978:Glutathione / Q000378:metabolism; D019803:Glutathione Disulfide / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D006801:Humans; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D016273:Occupational Exposure / Q000009:adverse effects; D010084:Oxidation-Reduction / Q000528:radiation effects; D011839:Radiation, Ionizing; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism
chemical_list: D000975:Antioxidants; D017382:Reactive Oxygen Species; D013481:Superoxides; D008315:Malondialdehyde; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005978:Glutathione; D019803:Glutathione Disulfide
keywords: Catalase; Glutathione; Low-level ionizing radiation; Malondialdehyde; Radiologic technologists; Superoxide; Superoxide dismutase
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