Cigarette smoking and inorganic dust in human lungs.

Whole left lungs from 18 smokers and 16 nonsmokers were obtained at autopsy and studied to determine the severity of subclinical emphysema and elemental dust loads of aluminum and silicon. Lungs selected were from individuals with work histories in non-dusty occupations and were sex- and age-matched by decade. Whole lung Gough sections were studied and emphysema was graded on a 0 to 100 score. Concentrations of aluminum and silicon were determined in homogenized-lyophilized lung of all 34 cases by plasma emission spectrometry. In addition, histological sections from 9 pairs of age-matched smokers and nonsmokers were studied by light microscopy and scanning electron microscopy in concert with semiquantitative x-ray spectrometric analysis of aluminum and silicon content in specific anatomical regions. The results of these studies indicate that aluminum and silicon concentrations increase in smokers with increased cigarette smoking. As expected, severity of pulmonary emphysema was associated with heavy cigarette smoking.