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BackgroundChest radiography (CXR) is inferior to Thin-section computed tomography in the detection of asbestos related interstitial and pleural abnormalities. It remains unclear, however, whether these limitations are large enough to impair CXR's ability in detecting the expected reduction in the frequency of these asbestos-related abnormalities (ARA) as exposure decreases.MethodsClinical evaluation, CXR, Thin-section CT and spirometry were obtained in 1418 miners and millers who were exposed to progressively lower airborne concentrations of asbestos. They were separated into four groups according to the type, period and measurements of exposure and/or procedures for controlling exposure: Group I (1940-1966/tremolite and chrysotile, without measurements of exposure and procedures for controlling exposure); Group II (1967-1976/chrysotile only, without measurements of exposure and procedures for controlling exposure); Group III (1977-1980/chrysotile only, initiated measurements of exposure and procedures for controlling exposure) and Group IV (after 1981/chrysotile only, implemented measurements of exposure and a comprehensive procedures for controlling exposure).ResultsIn all groups, CXR suggested more frequently interstitial abnormalities and less frequently pleural plaques than observed on Thin-section CT (p < 0.050). the odds for asbestosis in groups of decreasing exposure diminished to greater extent at Thin-section CT than on CXR. Lung function was reduced in subjects who had pleural plaques evident only on Thin-section CT (p < 0.050). in a longitudinal evaluation of 301 subjects without interstitial and pleural abnormalities on CXR and Thin-section CT in a previous evaluation, only Thin-section CT indicated that these ARA reduced as exposure decreased.ConclusionsCXR compared to Thin-section CT was associated with false-positives for interstitial abnormalities and false-negatives for pleural plaques, regardless of the intensity of asbestos exposure. Also, CXR led to a substantial misinformation of the effects of the progressively lower asbestos concentrations in the occurrence of asbestos-related diseases in miners and millers. ; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) ; FUNAPE - Goias State Government ; SAMA ; Brazilian Crysotile Institute (IBC) ; Univ São Paulo, Fac Med, Hosp Clin, Inst Heart,Div Pulm, São Paulo, Brazil ; Univ Estadual Campinas, Fac Ciencias Med, Dept Social & Prevent Med, Occupat Hlth Area, São Paulo, Brazil ; Fac Med Jundiai, Dept Clin Med, São Paulo, Brazil ; Universidade Federal de São Paulo, Escola Paulista Med, Dept Med, Div Resp, São Paulo, Brazil ; Universidade Federal de São Paulo, Escola Paulista Med, Dept Radiol, Div Radiol, São Paulo, Brazil ; Fleury Grp, Div Radiol, São Paulo, Brazil ; Delfin Clin, Dept Radiol, Salvador, BA, Brazil ; Portuguese Hosp, Salvador, BA, Brazil ; Univ British Columbia, Dept Radiol, Vancouver, BC, Canada ; Universidade Federal de São Paulo, Escola Paulista Med, Dept Med, Div Resp, São Paulo, Brazil ; Universidade Federal de São Paulo, Escola Paulista Med, Dept Radiol, Div Radiol, São Paulo, Brazil ; FAPESP: 1996/10415-6 ; CNPq: 420001/2006-9 ; FUNAPE - Goias State Government: 54.023 ; SAMA: 2P-04559-98 ; Web of Science