The respiratory health of carbon black workers

The respiratory health of 3,027 carbon black workers employed in 19 plants (18 Western Europe, 1 U.S.A.) was assessed by questionnaire and spirometry; chest radiographs were used to assess 935 workers in the group. The results showed that the group of workers who were exposed to carbon black dust had an increased prevalence of chronic cough, sputum production and wheezing and the mean forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1.0) and flow between 25% and 75% of the FVC (MMEF 25-75%) were significantly less than those of the nonexposed group. Multiple regression analysis showed that the decline in respiratory health was related to the influence of smoking and age, with only a small part being associated with the combined effects of dust exposure and age. A simple type of pneumoconiosis was found in 6 of the workers, all of whom had more than 10 yr of dust exposure. Carbon black should be regarded as a nuisance dust without specific effect on the lungs.