CANCER RISKS AMONG IRON AND STEEL WORKERS IN ANSHAN, CHINA .2. CASE-CONTROL STUDIES OF LUNG AND STOMACH-CANCER

Nested case-control interview studies of lung cancer (610 incident cas es), stomach cancer (292 incident cases), and 959 controls were conduc ted to follow up leads from a proportional mortality analysis of death s among male workers in a large integrated iron-steel complex in Ansha n, China. For lung cancer, after adjusting for the significant non-occ upational risk factors (smoking, other pulmonary disease, family histo ry of lung cancer, and low consumption of fruit or tea), risks were si gnificantly elevated for those employed for 15 or move years in smelti ng and rolling (OR = 1.5, CI = 1.1-2.2), in the fire-resistant brick f actory (OR = 2.9, CI = 1.4-5.9), in general loading (OR = 2.5, CI = 1. 0-6.1), and as coke overt workers (OR = 3.4; CI = 1.4-8.5). For stomac h cancer, after adjusting for consumption of pickled vegetables, prior gastric diseases, family history of stomach cancer, low intake of fru its and vegetables, and education, risks were significantly elevated f or those employed for 15 or more years in ore sintering and transporta tion (OR = 2.1, CI = 1.0-4.4), in the fire-resistant brick factory (OR = 2.5, CI = 1.1-5.8), in general loading (OR = 3.2, CI = 1.2-8.9), as boilerworkers and cooks (OR = 2.6, CI = 1.2-5.6), and as coke oven wo rkers (OR = 5.4, CI = 1.8-16.0). For both lung and stomach cancers, si gnificant dose-response gradients were observed for exposure to total dust and benzo(a)pyrene, but not for specific chemical components of d ust. Overall, long-term steel workers with exposure to workplace pollu tants had a 40% increased risk of both lung and stomach cancers. These case-control studies confirm many of the occupational findings report ed in the proportionate mortality analysis, and suggest avenues for fu rther work to evaluate the carcinogenicity of individual components of dust. (C) 1996 Wiley-Liss, Inc.