Radiation exposure from work related medical x rays at the Portsmouth Naval Shipyard.
Daniels-R; Kubale-T; Spitz-H
Occup Environ Med 2005 Nov; 62(11):e25
Introduction: Previous analyses suggest that worker radiation dose may be significantly increased by routine occupational x ray examinations. Medical x ray exposures for 570 civilian workers employed at the Portsmouth Naval Shipyard (PNS) at Kittery, Maine were estimated to determine the contribution of work related chest x ray (WRX) relative to conventional workplace radiation sources. Methods: Methods were developed to estimate absorbed doses to the active (hematopoietic) bone marrow from x ray examinations and workplace exposures using data extracted from worker dosimetry records (8468) and health records (2453). Misclassification from the omission of occupational x ray examinations was evaluated and dose distributions were examined for radiation and non-radiation workers. Results: Photofluorographic chest examinations resulted in 82% of the dose to active bone marrow from medical x ray sources. On average, radiation monitored workers received 26% of their dose from WRX and received 45% more WRX exposure than non-radiation workers. Conclusions: WRX can result in a significant fraction of the total bone marrow dose, especially for radiation workers who were more likely to be subjected to routine medical monitoring. Omission of WRX from the exposure assessment can cause misclassification, which may attenuate the risk for cancers induced by workplace exposures.
X-ray-absorption; X-ray-equipment; Radiation; Radiation-exposure; Medical-equipment; Medical-treatment; Shipyard-industry; Shipyard-workers; Chest-X-rays
National Institute for Occupational Safety and Health, Division of Surveillance, Hazard Evaluations, and Field Studies, 4676 Columbia Parkway, Cincinnati, OH 45226
Occupational and Environmental Medicine