A recent publication, referenced here, reports twenty eight 911 rescue workers with a sarcoid type clinical picture. The article, Published in the May 2007 issue of Chest is available in abstract form here.
Patient were described with hilar nodes and parenchymal changes as well as extra-pulmonary findings.
There is some precedent for the relationship between occupational/environmental exposures and granulomatous type pulmonary reaction. For example,exposure to zirconium has been reported to cause pulmonary granulomatous reactions. Much less obscure has been the well established relationship between exposure to beryllium oxide-used in the manufacture of fluorescent light bulbs-and a clinical picture at times indistinguishable from sarcoid. Unique among pneumoconioses a blood test (beryllium specific lymphocyte proliferation test) is available for specific diagnosis.
Sarcoid is generally considered a hypersensitivity reaction to something (or somethings) but a common etiology for all cases has eluded detection.
It is not surprising that the mixture of respirable particles to which 911 rescuers were exposed would cause lung disease of some sort. Harder to understand is the authors of the Chest article observation that NYFD members demonstrated a higher than expected rate of sarcoid preceding the 911 catastrophe. On the other hand, clusters of cases have appeared from time to time in various places and among various occupational groups (e.g nurses) but over time no confirming data developed that indicated a real pattern.