Not your Typical Iron Lung: A micro-XRF Study of a Soldier's Lungs

U.S. soldiers returning from combat in the Middle East are showing an unusual incidence of pulmonary pathophysiology, specifically, an increased incidence of asthma in patients exhibiting no previous symptoms. One such returned soldier has experienced decreased lung capacity with physical activity since returning from Iraq where the patient managed a troop laundry facility. After chest x-rays showed diffuse opacity, a lung biopsy was performed. The biopsy was sectioned on Ultralene Mylar and Silicon Nitride mounts and studied at Brookhaven National Laboratory’s National Synchrotron Light Source at X-26-A and X-27-A using coupled micro-X-ray Fluorescence (u-XRF) and micro-X-ray Diffraction (u-XRD). Analysis of multiple sections revealed a high correlation between iron and titanium. Titanium has no natural source in the body and is not a micronutrient. Areas with high iron and titanium contents were selected for u-XRD. Small grain sizes and strong scatter from the paraffin (the setting agent used to maintain tissue morphology) prevent exact determination of the contaminating species, but iron/titanium ratios and comparison with known XRD patterns indicate an iron titanium oxide with a high iron/titanium ratio. These results require further exploration in other patients and possible contaminant sources such as oxidized explosive materials and environmental dusts.