Lung cancer risk among bricklayers and other construction workers: A pooled analysis of case-control studies

Background Several occupations within the construction sector are included in lists of occupations known (list A, including insulators and pipe coverers, roofers, asphalt workers, painters) or suspected (list B, including carpenters and joiners, operators of excavating machines) to be associated with lung cancer risk. Other jobs, notably bricklayers, are not included in those lists, although they may be exposed to known carcinogens, in particular crystalline silica (especially during cutting operations of bricks and stones), and several studies reported an excess of lung cancer among them. Objectives We present preliminary analyses of lung cancer risk among bricklayers and other construction workers within the frame of the SYNERGY project (http://synergy.iarc.fr), a large international pooled analysis of case-control studies on the joint effects of occupational carcinogens in the development of lung cancer. Methods Industries and occupations were coded following the International Standard Industrial Classification (ISIC 1968/1971) and the International Standard Classification of Occupations (ISCO 1968). Because of coding heterogeneity across study centres, in the analysis of “bricklayers” we pooled the following ISCO codes together: 95120 (bricklayers), 95140 (stonemasons), 95190 (other bricklayers, stonemasons and tile setters), and 95910 (housebuilders). For men employed in selected occupations in the construction sector (ISIC code 5000), we calculated odds ratios (ORs) and their 95 % confidence intervals (CIs) adjusted for study centre, age, cigarette smoking (ever/never, log-transformed pack-years, time since quitting), and employment in list A or B occupations. Results The pooled dataset included 15,608 cases and 18,531 controls from 16 studies in 13 European countries, Canada, Hong-Kong, and New Zealand. The number of blue collar cases/controls ever employed in non-list A or B occupations in the construction industry was 3,757/3,122. The majority (977 cases, 767 controls) was employed as bricklayers, with an OR of 1.4 (95 % CI: 1.3-1.6) and a clear positive trend with length of employment (p