Economic status and occupational correlates of stomach cancer in the rubber industry.
Associations between stomach cancer and occupational exposure to rubber remain uncertain, and thus far only a few studies have been carried out to investigate risks of stomach cancer in different jobs in the rubber industry, and confounding of the risk/exposure relationship by non-occupational risk factors, especially by the economic status. This study was aimed to explore these questions. Following a case-cohort design, we used the data of 36 stomach cancer deaths in 1973-95 and a random sample (sub-cohort) of 188 from among 1598 subjects employed in a rubber plant in Shanghai, China. We analysed stomach cancer risks by the economic status, smoking, alcohol consumption, and residential exposure to coal burning-related pollution, etc., and assessed by jobs and years, unadjusted and adjusted. The rate ratios for stomach cancer were found to be 1.70 for 1-19 yr of employment and 1.79 for 20 or more yr of employment in the inner tire tube department. After the economic status was adjusted, the rate ratios were 1.54 and 1.64, respectively. Although the front processing of rubber was also included in our analysis no evidence of any excess risk of stomach cancer was found. Rate ratios adjusted for four job groups were the highest in the low income group. The association followed a pattern of a dose-response relationship--increasing rate ratios correlated with decreasing annual income (statistic trend: chi 2(1) = 8.35, p = 0.004). The data obtained suggest that excess risks of stomach cancer in the rubber workers were mainly related to their economic status and only slightly (some 1.6) to the talc powder exposure. Results of this study fail to provide any statistically significant evidence to support the hypothesis that there was high risk of death from stomach cancer among the rubber workers employed in high dusty departments.
Ke
L
L
Preventive Branch, Shantou University Medical College, China.
Shunzhang
Y
Y
D002681:China / Q000453:epidemiology; D006801:Humans; D007182:Income; D009784:Occupational Diseases / Q000453:epidemiology*; D011897:Random Allocation; D012408:Rubber; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000401:mortality
D012408:Rubber