The evolving spectrum of pulmonary disease in responders to the World Trade Center tragedy.

On September 11, 2001, events at the World Trade Center (WTC) exposed residents ofNew York City to WTC dust and products of combustion and pyrolysis. The majority ofWTC-exposed fire department rescue workers experienced a substantial decline in airflowover the first 12 months post-9/11, in addition to the normal age-related declinethat affected all responders, followed by a persistent plateau in pulmonary function inthe 6 years thereafter. The spectrum of the resulting pulmonary diseases consists ofchronic inflammation, characterized by airflow obstruction, and expressing itself indifferent ways in large and small airways. These conditions include irritant-inducedasthma, non-specific chronic bronchitis, aggravated pre-existing obstructive lung disease(asthma or COPD), and bronchiolitis. Conditions concomitant with airwaysobstruction, particularly chronic rhinosinusitis and upper airway disease, and gastroesophagealreflux, have been prominent in this population. Less common have beenreports of sarcoidosis or interstitial pulmonary fibrosis. Pulmonary fibrosis and bronchiolitisare generally characterized by long latency, relatively slow progression, and asilent period with respect to pulmonary function during its evolution. For these reasons,the incidence of these outcomes may be underestimated and may increase overtime. The spectrum of chronic obstructive airways disease is broad in this populationand may importantly include involvement at the bronchiolar level, manifested as smallairways disease. Protocols that go beyond conventional screening pulmonary functiontesting and imaging may be necessary to identify these diseases in order to understandthe underlying pathologic processes so that treatment can be most effective.