RT Journal Article SR Electronic T1 Technetium-99m DTPA Aerosol Contamination in Lung Ventilation Studies JF Journal of Nuclear Medicine Technology JO J. Nucl. Med. Technol. FD Society of Nuclear Medicine SP 43 OP 44 VO 26 IS 1 A1 Williams, Daniel A. A1 Carlson, Christina A1 McEnerney, Kathleen A1 Hope, Ellen A1 Hoh, Carl K. YR 1998 UL http://tech.snmjournals.org/content/26/1/43.abstract AB Contamination of working areas by 99mTc DTPA aerosol is of concern to nuclear medicine technologists. This study sought to determine the extent of 99mTc DTPA contamination to technologists, and to localize sources of aerosol leakage so that methods could be identified that would minimize contamination. Methods: Fifty to eighty millicuries 99mTc DTPA, diluted to a volume of 4–5 ml with normal saline, were injected into the nebulizing chamber of two commercially available inhalation aerosol systems. The patient’s nostrils were clamped and a damp washcloth was wrapped around the patient’s mouth. An alcohol swab was placed in the exit port of the exhaust filter in each delivery system, and the technologist involved wore a face mask during the inhalation phase. The patient breathed DTPA-labeled aerosol by mouth until the counting rate in the lungs was four times greater than the counting rate from the pulmonary perfusion phase. Connecting joints of the delivery system were then wipe tested. Last, a Geiger-Mueller detector (pancake probe) was used to survey all device components. Readings above 0.05 mR/hr were considered contaminated. Results: The patient was the greatest source of leakage as determined by the damp washcloth, followed by the joints of the tubes of the delivery system and, finally, the system’s exhaust filter. Contamination readings from face masks worn by technical personnel during the lung ventilation studies were slightly greater than 0.05 mR/hr. Conclusion: The findings support trace levels of contamination to both the technologist and room while performing 99mTc DTPA aerosol ventilation studies. Comparative data using the two delivery systems revealed little difference in sources of leakage and little variation in contamination measurements.