LIFE-STYLE, ENVIRONMENTAL-POLLUTION AND LUNG-CANCER IN CITIES OF LIAONING IN NORTHEASTERN CHINA

Several studies were conducted in cities of Liaoning Province, one of the areas of China with heavy concentrations of industry, to investiga te the effects of life-style factors and environmental pollutants on l ung cancer causation. A case-control study involving 1249 lung cancer patients and 1345 population-based controls was conducted in 1985-1988 in Shenyang, the capital of Liaoning. Cigarette smoking was found to be the principal cause of lung cancer in this population, accounting f or 55% of the disease in males and 37% in females. There was also a si gnificant increase in lung cancer risk associated with an overall inde x of indoor air pollution due to coal-burning emission. The population attributable risk (PAR) for indoor air pollution was 13% for males an d 17% for females. Risks were significantly increased for workers in t he non-ferrous smelter (odds ratio (OR) = 2.6, 95% CI, 1.3-5.1), chemi cal and drug manufacturing (OR = 3.0, 95% Cr, 1.0-8.0), and the glass and pottery industry (OR = 1.6, 95% CI, 1.0-2.5). Studies in the Ansha n Iron-Steel Complex showed a significant excess of lung cancer for wo rkers exposed to a variety of dusts. A standardized proportional morta lity ratio (SPMR) study of 8887 deaths during 1980-1989 among male wor kers of the complex indicated a 37% excess risk of lung cancer compare d to residents of the city. A nested case-control study was then condu cted in that complex. A total of 610 cases of lung cancer diagnosed du ring 1987-1993 and 959 randomly selected controls from 196 993 active and retired employees of the complex were interviewed. Historical moni toring records for dust and benzo(a)pyrene (B(a)P) were collected from 1956-1992 to calculate cumulative exposure for each person. Results s uggested that risks were increased for all occupations in which there was exposure to dusts, with the highest risks seen among coke oven wor kers (OR = 3.5, 95% CI, 2.0-6.4) and fire-resistant brick makers (OR = 2.9, 95% CI, 1.9-4.4). Significant dose-response patterns between cum ulative total dust, cumulative total B(a)P and lung cancer risk were o bserved. The findings suggest that smoking and environmental pollution combine to account for elevated rates of lung cancer in cities of nor theastern China.