Objectives for the SYNERGY project

The SYNERGY project holds individual lifetime data on occupations and smoking history for >17 700 lung cancer cases and >21 800 control subjects. This database provides the best available tool for estimating the joint effects of occupational exposure to asbestos, PAHs, nickel, chromium and silica.

The main aims of the SYNERGY project are:

  • To assemble and pool eligible lung cancer studies;
    • To assemble and evaluate the best available exposure information, and create an exposure database (ExpoSYN);
    • To develop a project-specific job-exposure matrix (SYN-JEM);
    • To develop exposure variables based on the SYN-JEM and other parameters of exposure assessment;
    • To asses the exposure-response relationships for the lung carcinogens selected for evaluation;
    • To estimate the interactions between occupational carcinogens;
    • To investigate the effects of smoking as a potential confounder or effect modifier.

    The criteria for selecting asbestos, PAH, nickel, chromium and respirable crystalline silica as the exposures of interest were:
    • Classification in IARC Group 1 (carcinogenic to humans);
    • Prevalence of joint exposure in study populations;
    • Availability of quantitative exposure data;
    • Possibility to disentangle the effects of correlated occupational exposures;
    • Possibility to disentangle occupational exposures from exposures in general population;
    • Mechanistic considerations (shared or different modes of biological action).
    • Relevance for prevention;
    • Relevance for compensation;