Iraq Dust Is Respirable, Sharp, and Metal-Laden and Induces Lung Inflammation With Fibrosis in Mice via IL-2 Upregulation and Depletion of Regulatory T Cells

Szema, Anthony M. MD; Reeder, Richard J. PhD; Harrington, Andrea D. PhD; Schmidt, Millicent MS; Liu, Jingxuan MD, PhD; Golightly, Marc PhD; Rueb, Todd BS; Hamidi, Sayyed A. MD

Journal of Occupational & Environmental Medicine:
doi: 10.1097/JOM.0000000000000119
Original Articles
Press
Abstract

Objectives: Determine whether surface dust grab samples taken from a large military base in Iraq are toxic and respirable.

Methods: X-ray diffraction for mineral content, x-ray fluorescence for elemental content, in vivo mouse dust challenges for assessment of histological changes, bronchoalveolar lavage for cytokines, polarizing light microscopy for crystals in lung tissue, and Fluorescence Activated Cell Sorting for cell surface and intracellular markers were utilized.

Results: Camp Victory, Iraq dust taken during wartime contains respirable particles 2.5 microns in size, constituting particulate matter air pollution. Dust particles are angular and have sharp edges. Trace metals (including titanium) calcium and silicon are present. Mice with airway instillation of dust have polarizable crystals in lung and septate inflammation. Regulatory T cells (CD4+CD25+FOXP3+) are decreased in thymus and spleen. Interleukin-2 (IL-2) is upregulated in bronchoalveolar lavage.

Conclusions: Respirable Iraq dust leads to lung inflammation in mice similar to that seen in patients with polarizable crystals, which seem to be titanium.

Author Information

From the Departments of Medicine (Drs Szema and Hamidi) and Pathology (Drs Liu and Golightly and Mr Rueb), Stony Brook University School of Medicine, Stony Brook, NY; Department of Geosciences (Dr Reeder and Ms Schmidt), Stony Brook University, Stony Brook, NY; and New York University Department of Occupational and Environmental Medicine (Dr Harrington), New York.

Address correspondence to: Anthony M. Szema, MD, Department of Medicine, Stony Brook University School of Medicine, 100 Nicolls Rd, Stony Brook, NY 11794 (anthony.szema@stonybrookmedicine.edu).

* Recently completed grant from Merck to study dust mite antigen on lung epithelial cells in vitro $15K September 2013

* Garnett McKeen Labs completed grant July 2012 to study drug RUX as an anti–lung injury agent for Iraq dust $60K

* National Institute of Environmental Health Sciences R21 2013-6 coinvestigator to study asthma in Hurricane Sandy victims who were previously World Trade Center disaster workers (PI Adam Gonzalez, PhD, Stony Brook University)

* Grant applications submitted to VA Merit Review Program to study regulatory T cells in mice exposed to Iraq dust fall 2013

* Grant application submitted to Lupus Research Institute to study regulatory T cells in VIP knockout mice December 2013

* In contract negotiation with Phasebio Corporation as a consultant for their VIP drug December 2013

* Developing a smartshirt to measure lung physiology with associate dean of curriculum at Stony Brook University and associate Dean of Engineering December 2013

* Private practice Three Village Allergy & Asthma, PLLC, South Setauket, New York

* Chief, Allergy Section, Veterans Affairs Medical Center, Northport, New York

Authors Szema, Reeder, Harrington, Schmidt, Liu, Golightly, Rueb, and Hamidi have no relationships/conditions/circumstances that present potential conflict of interest.

The JOEM editorial board and planners have no financial interest related to this research.

Copyright © 2014 by the American College of Occupational and Environmental Medicine