For the first time ever, the National Institute for Occupational Safety and Health (NIOSH) has released two separate guidelines for the same chemical based on size – and it’s all about nanotechnology.
NIOSH Director John Howard, M.D., said that the information in "Current Intelligence Bulletin 62: Occupational Exposure to Titanium Dioxide" reflects the institute’s efforts to better understand nanoparticles.
"As NIOSH continues to conduct research into the occupational health implications of nanotechnology, guidance of this nature will play an increasingly important role in fashioning protective occupational safety and health practices,” Howard said.
Titanium dioxide is an insoluble white powder that is used in many commercial products, including paint, cosmetics, plastics, paper, and food. In the new publication, NIOSH examines data regarding the potential likelihood that occupational exposure to TiO2 by inhalation may result in adverse health effects. The TiO2 CIB makes recommendations for occupational exposure limits and suggests techniques for monitoring and controlling worker exposure. Specifically the TiO2 CIB:
- Reviews data relevant to assessing the carcinogenicity and other adverse health effects of TiO2.
- Provides quantitative risk assessments and recommended exposure limits (RELs) for fine and ultrafine TiO2. The two RELs by particle size reflect laboratory data showing that ultrafine TiO2 particles demonstrated greater potency in laboratory rats than fine particles did, when the dose was expressed by particle surface area. This greater potency was associated with the greater surface area of the ultrafine particles for a given mass.
- Describes exposure monitoring techniques, exposure control strategies, and future research needs.