Pneumoconiosis Among Activated-Carbon Workers

Abstract

• The prevalence of respiratory symptoms and chest radiographic and spirometric abnormalities was assessed among 397 employees of an activated carbon plant. Definite radiographic findings of pneumoconiosis, consisting of p-type, rounded opacities in the lower lung fields without fibrosis or coalescence, were present in 9.6% of men and were related to cumulative dust exposure. Lesser degrees of radiographic abnormality suggesting pneumoconiosis were present in 11% of men and 2% of women. Spirometric values were substantially lower in blacks than in whites. However, cumulative dust exposure was not an important determinant of pulmonary function in either race. Review of lung biopsy specimens that had been obtained previously in two employees revealed extensive carbon deposition but minimal associated fibrosis.

Prolonged inhalation of activated carbon dust leads to pulmonary deposition of carbon and radiographic signs of pneumoconiosis; such deposition has little, if any, effect on respiratory symptoms or pulmonary function.