The Acute and Long-Term Effects of Middle East Sand Particles on the Rat Airway Following a Single Intratracheal Instillation

Military personnel deployed in the Middle East have emphasized concerns regarding high levels of dust generated from blowing desert sand and the movement of troops and equipment. Airborne particulate matter levels (PM10; PM < 10 μm) in the region may exceed 1500 μg/m3, significantly higher than the military exposure guideline (MEG) of 50 μg/m3. Increases in PM10 have been linked to a rise in incidences of asthma, obstructive pulmonary disease, lung cancer, and cardiovascular diseases. Male Sprague-Dawley rats received a single intratracheal (IT) instillation of 1, 5, or 10 mg of Middle East PM10 collected at a military occupied site in Kuwait, silica (positive control), or titanium dioxide (TiO2; negative control) suspended in 400 μl sterile saline, or saline alone (vehicle control). Twenty-four hours, 3 d, 7 d and 6 mo postexposure (n = 15/group), organs including lung were evaluated for histopathological changes and for particle contaminants. Bronchoalveolar fluid (BALF) was also analyzed for cellular a...