California’s Office of Environmental Health Hazard Assessment (OEHHA) has adopted a new regulation establishing No Significant Risk Levels (NSRLs) for titanium dioxide under Proposition 65. This action specifically targets airborne, unbound particles of respirable size and became effective on October 1, 2025.

The establishment of these NSRLs provides a clear ‘safe harbor’ threshold for businesses. If exposure from a product is below these levels, a Prop 65 warning for cancer risk is not required.

The New NSRLs:

The OEHHA has set two distinct daily exposure limits based on particle size:

  • 440 micrograms per day for airborne, unbound titanium dioxide particles with diameters of 10 micrometers or less
  • 44 micrograms per day for airborne, unbound titanium dioxide particles with diameters of 08. micrometers or less

Please contact us if you would like assistance with formula reviews or exposure assessments to ensure compliance with Prop 65.