Journal of Nanoparticle Research

, Volume 12, Issue 6, pp 1971–1987 | Cite as

Occupational exposure limits for nanomaterials: state of the art

  • P. A. SchulteEmail author
  • V. Murashov
  • R. Zumwalde
  • E. D. Kuempel
  • C. L. Geraci
Review Paper


Assessing the need for and effectiveness of controlling airborne exposures to engineered nanomaterials in the workplace is difficult in the absence of occupational exposure limits (OELs). At present, there are practically no OELs specific to nanomaterials that have been adopted or promulgated by authoritative standards and guidance organizations. The vast heterogeneity of nanomaterials limits the number of specific OELs that are likely to be developed in the near future, but OELs could be developed more expeditiously for nanomaterials by applying dose–response data generated from animal studies for specific nanoparticles across categories of nanomaterials with similar properties and modes of action. This article reviews the history, context, and approaches for developing OELs for particles in general and nanoparticles in particular. Examples of approaches for developing OELs for titanium dioxide and carbon nanotubes are presented and interim OELs from various organizations for some nanomaterials are discussed. When adequate dose–response data are available in animals or humans, quantitative risk assessment methods can provide estimates of adverse health risk of nanomaterials in workers and, in conjunction with workplace exposure and control data, provide a basis for determining appropriate exposure limits. In the absence of adequate quantitative data, qualitative approaches to hazard assessment, exposure control, and safe work practices are prudent measures to reduce hazards in workers.


Nanomaterials Regulation Risk assessment Occupational safety and health Carbon nanotubes Control banding 



The authors thank the following for comments on earlier drafts: Frank Mirer, Chris Laszcz-Davis, Larry Gibbs, Mike Jayjock, Bruce Naumann, Bruno Orthen and Andrew Maynard.


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Copyright information

© US Government 2010

Authors and Affiliations

  • P. A. Schulte
    • 1
    Email author
  • V. Murashov
    • 1
  • R. Zumwalde
    • 1
  • E. D. Kuempel
    • 1
  • C. L. Geraci
    • 1
  1. 1.National Institute for Occupational Safety and HealthCenters for Disease Control and PreventionCincinnatiUSA

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