Objectives Besides radiation, nuclear workers can be exposed to a variety of chemical hazards. We examined the effect of chemical exposure on cancer mortality of French nuclear workers at the AREVA NC Pierrelatte establishment.

Methods A cohort of 2,897 uranium processing workers employed for at least 6 months was followed up from 1968 to 2006. Exposures to uranium and potentially carcinogenic chemicals were assessed using plant-specific job-exposure matrix. Lung, lympho haematopoietic, kidney and bladder, brain and other central nervous system (BCNS), and prostate cancers mortality hazard ratios (HRs) were estimated for each chemical exposure using Cox regression models stratified on sex and calendar period, and adjusted for socio-economic status. An effect of co-exposures to uranium and other chemicals was examined using additional adjustments.

Results Exposure to aromatic solvents was associated with increased risk of BCNS malignancies after adjustment for other chemicals (HR = 6.53, 95% CI = 1.14–37.41) and other chemicals and uranium (HR = 7.26, 95% CI = 0.90–58.19). Significantly elevated risk of lung cancer related to exposure to chromium (VI) compounds was also observed, based on only two deaths among exposed workers.

Conclusions Exposure to aromatic solvents was associated with the risk of BCNS cancers. The latter risk might be increased by uranium co-exposure. A potential excess risk of lung cancer related to chromium (VI) exposure observed among nuclear workers should be confirmed in further studies.