A review of studies of occupational titanium dioxide (TiO2) exposure was conducted, and results from the three industry-based cohort mortality studies were summarized using meta-analysis.
Summary standardized mortality ratios (SSMR) and summary Cox regression coefficients from exposure–response models were derived using random effects models.
Results from studies of 24,312 TiO2 production workers were combined. SSMRs for lung cancer, all causes, all cancer, and non-malignant respiratory disease were 1.10 (95% confidence interval [CI]: 0.91 to 1.32), 0.85 (95% CI: 0.81 to 0.89), 0.92 (95% CI: 0.82 to 1.03), and 0.85 (95% CI: 0.71 to 1.02), respectively. For lung cancer, the summary hazard ratio for a 1 mg/m3 year increase in cumulative exposure was 0.999 (0.997 to 1.002).
Consistent with other published qualitative reviews, there is no clear evidence of an association between occupational exposure to TiO2 and lung cancer.
The Chemours Company, Wilmington, Delaware (Dr Le, Dr Warheit); Causation Ltd., Macclesfield, UK (Dr Tomenson); EpidStat Institute, Rockville, Maryland (Dr Fryzek); Oak Ridge Associated Universities, Oak Ridge, Tennessee (Dr Golden, Dr Ellis).
Address correspondence to: Hien Q. Le, PhD, MPH, The Chemours Company, Wilmington, DE (firstname.lastname@example.org).
Funding Sources: This work was a collaboration with the Titanium Dioxide Industry Consortium (TDIC). Funding was provided by the TDIC and The Chemours Company. Drs Le and Warheit are employed by Chemours. Dr Tomenson received funding from TDIC. Drs Golden and Ellis received funding from TDIC and Chemours. Dr Fryzek reports no conflicts of interest. The findings and conclusions of the scientific research described in this study are our own professional opinions and do not necessarily represent the official views of Chemours or its employees and shareholders, and the Oak Ridge Associated Universities.