High-resolution computed tomography abnormalities in ex-insulators annually exposed to asbestos dust

Background To characterize the effects of high asbestos exposure during ann ual periods of insulation. Method 170 ex-workers underwent clinical examination, spirometry, standard chest Xrays and high-resolution computed tomography (HRCT). Asbestos exposu re was retrospectively assessed for latency, duration, and intensity. Results Sixty-six percent of these workers were annually exposed to high co ncentrations of asbestos dust. Respiratory symptoms were mild. One hundred and nineteen subjects had pleural or pulmonary changes on HRCT, compatible with asbestos exposure. Localized pleural thickening was found in 113 subje cts (66.5%); pulmonary nodules or lines in 35 (20.6%). The presence of pleu ral plaques was linked to intensity of asbestos exposure (P <.01), and leng th of employment (P <.05). Parenchymal lesions were related to intensity (P <.05) and duration of exposure (P <.05). Lung function of subjects with X- ray changes was not significantly altered. Conclusion: Annual asbestos exposure led to a high prevalence of pleural pl aques and to mild parenchymal anomalies. (C) 1999 Wiley-Liss, Inc.