Objectives A feasibility study has shown that a scientifically rigorous and comprehensive epidemiological study of workers involved in the manufacture or production of tungsten carbide with a cobalt binder is feasible, and should include workers from sites in the United States and in Europe. Objectives include: (i) to investigate the total and cause-specific mortality experience of current and former workers as compared with the corresponding national and local populations from which the workforces were drawn, with adjustment for potential confounding factors; (ii) to characterise as completely as possible the current and past working environment of the study participants; and (iii) to determine the relationship between level and duration of exposures and mortality from lung cancer with analytic adjustment for important potential co-exposures, including tobacco smoke. The study is funded by the International Tungsten Industry Association.

Methods The study cohort will be enumerated using human resources data, with cross-checks for completeness against pension, payroll, occupational health and other sources. All available occupational hygiene data will be extracted to facilitate a study-wide exposure assessment.

Results Initial meetings have been held with the two UK factories to establish the scope and quality of demographic and industrial hygiene data. In parallel with this an application has been submitted to an ethics committee and the National Information Governance Board, the latter seeking to obtain an exemption from having to gain positive consent for study participants. A worker leaflet explaining the study has been drafted for inclusion in the ethical submission. Work to determine the optimum way to extract the data from the factories, is currently underway.

Conclusions This large study will represent multiple companies, countries and manufacturing processes and will be larger, more robust and more definitive than any hard-metal manufacturing epidemiological study done to date.