Tobacco smoking among chrysotile asbestos workers in Asbest in the Russian Federation

A historical cohort study of cancer mortality is being conducted among workers in a chrysotile mine and its enrichment factories in the town of Asbest, Russian Federation. Because individual-level information on tobacco use is not available for Asbest Chrysotile Cohort members, a cross-sectional survey of smoking behaviours was conducted among active and retired workers.

Self-administered questionnaires were completed by active workers during meetings organised by occupational safety personnel. Retired workers completed questionnaires during meetings of the Veterans Council or were interviewed via telephone or in person. Of the respondents, 46% could be linked to the Asbest Chrysotile Cohort. Among those, logistic regression models were used to assess associations between smoking and cumulative dust exposure.

Among men, smoking prevalence was high and relatively consistent across birth decades (average, 66%), and was similar in workers across all levels of cumulative dust exposure (p trend, 0.44). Among women, the prevalence increased from <10% in those born before 1960 to 30% in those born after 1980, and smoking was associated with exposure to dust versus not exposed to dust (p value, 0.006), but did not vary appreciably across workers in different cumulative dust exposure categories (p trend, 0.29).

Our study suggests that cross-sectional surveys may be a useful tool for understanding the potential health impact from smoking in occupational cohorts, including possible confounding by smoking. This survey showed that adjustment at the age group level among women is needed to reduce residual confounding and account for smoking patterns, which have changed substantially over time.