title: Respirable quartz dust exposure and airway obstruction: a systematic review and meta-analysis.
abstract: Studies on exposure to respirable quartz dust at the workplace and the development of chronic obstructive pulmonary disease (COPD) were selected into a systematic review and meta-analysed to obtain an overall estimate of forced expiratory volume in 1 s (FEV1) and FEV1/forced vital capacity (FVC) reduction. PubMed and Embase were searched from 1970 to 2010. In total, 257 cross-sectional and longitudinal studies were identified that reported on inorganic dust exposure and had available lung function data. Of the 55 publications which met our inclusion criteria, 11 reported on associations with occupational exposure to respirable quartz dust. The combined average effect estimate of respirable quartz dust on spirometric parameters was obtained using a random effects model meta-analysis. Between-study heterogeneity was assessed via the I(2) statistic. Most studies found a significant negative association of FEV1 and FEV1/FVC related to increasing exposure to crystalline quartz at the workplace. One study found an effect only for smokers, and one did not observe such an effect at all. The meta-analysis of cross-sectional studies showed that the mean ratio FEV1 to FVC was reduced and FEV1 of workers exposed to respirable quartz dust was 4.6% less than predicted compared with workers with no/low exposure. Both results showed a statistically significant difference. Occupational exposure to respirable quartz dust was associated with a statistically significant decrease in FEV1 and FEV1/FVC, revealing airway obstruction consistent with COPD.
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology I, Neuherberg, Germany.
authors.forename: Irene
authors.initials: I
authors.lastname: Brüske
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology I, Neuherberg, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Thiering
authors.affiliation: Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology I, Neuherberg, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Heinrich
authors.affiliation: Ludwig-Maximilians-University, Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Inner City Clinic, University Hospital of Munich, Munich, Germany.
authors.forename: Katharina M
authors.initials: KM
authors.lastname: Huster
authors.affiliation: Ludwig-Maximilians-University, Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Inner City Clinic, University Hospital of Munich, Munich, Germany DZL Munich, Member of the German Center for Lung Research (DZL), Munich, Germany.
authors.forename: Dennis
authors.initials: D
authors.lastname: Nowak
mesh_terms: D004391:Dust; D005541:Forced Expiratory Volume; D006801:Humans; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology; D009784:Occupational Diseases / Q000209:etiology*; D016273:Occupational Exposure / Q000009:adverse effects*; D052638:Particulate Matter / Q000009:adverse effects*; D029424:Pulmonary Disease, Chronic Obstructive / Q000209:etiology* / Q000503:physiopathology; D011791:Quartz / Q000009:adverse effects*; D014797:Vital Capacity
chemical_list: D004391:Dust; D052638:Particulate Matter; D011791:Quartz