NIOSH Current Intelligence Bulletin: Evaluation of Health Hazard and Recommendations on Occupational Exposure to Titanium Dioxide

Project Information

Principal Investigator	Christine Sofge
Institution	National Institute for Occupational Safety and Health
Project URL	View
Relevance to Implications	High
Class of Nanomaterial	Engineered Nanomaterials
Impact Sector	Human Health
Broad Research Categories	Hazard Control Characterization Risk Assessment
NNI identifier

Funding Information

Country	USA
Anticipated Total Funding	n/a
Annual Funding	n/a
Funding Source	NIOSH
Funding Mechanism	Intramural
Funding Sector	Government
Start Year	2003
Anticipated End Year	2008

Abstract/Summary

This Current Intelligence Bulletin will provide an updated review of the scientific literature pertaining to adverse health effects in workers exposed to titanium dioxide, including epidemiology studies and experimental studies in animals. A quantitative risk assessment will be performed using both lung cancer and noncancer (pulmonary inflammation) data in rats inhaling either fine or ultrafine titanium dioxide. The rat-based estimates of internal particle surface area dose in the lungs (at specified risk levels) will be extrapolated to humans using lung dosimetry models, and the rat-based excess risk estimates for lung cancer will be compared to the confidence intervals on risk from the epidemiological studies. The recommended exposure limits will account for particle surface area differences at given mass concentrations of fine or ultrafine titanium dioxide, as well as associated differences in toxicity. The current cancer classification for titanium dioxide will be evaluated and updated recommendations will be provided.