Overview of environmental pulmonary disease

[Justin Bieber]

Environmental pulmonary diseases result from inhalation of dusts, allergens, chemicals, gases, or environmental pollutants. The lungs are continually exposed to the external environment and are susceptible to a host of environmental challenges. Pathologic processes can involve any part of the lungs, including the

Airways (eg, in occupational asthma, reactive airways dysfunction syndrome, toxic inhalations, air pollution-related illness, or byssinosis)
Lung parenchyma (eg, in pneumoconioses, hypersensitivity pneumonitis, or silicosis)
Pleura (eg, in asbestos-related diseases)

Environmental inhalation exposure has long been known to be a risk factor for asthma (see Occupational Asthma), but it is also increasingly being recognized as a non-smoking cause of COPD (chronic obstructive pulmonary disease). The American Thoracic Society estimates the population-attributable fraction of COPD related to occupational and environmental exposures to be about 20% (ie, COPD incidence and mortality would decline by about 20% if environmental exposures were reduced to zero).
Clinicians should take an occupational and environmental history in all patients, asking specifically about past and current exposure to vapors, gases, dust, fumes, and/or biomass smoke (ie, from burning wood, animal waste, crops). Any positive response is followed by more detailed questions.