Draft NIOSH Report Focuses on Developing OELs, OEBs for Engineered Nanomaterials

A new draft technical report published by NIOSH describes the agency’s proposed approach to developing occupational exposure limits (OELs) or occupational exposure bands (OEBs) for engineered nanomaterials. According to NIOSH, the publication is intended as a resource for risk management decision-making to protect workers from potential exposures to engineered nanomaterials. Specifically, the report seeks to cover state-of-the-science approaches for developing categorical OELs or OEBs for engineered nanomaterials that lack sufficient experimental data to develop substance-specific OELs. NIOSH describes categorial OELs as “one approach to estimating exposure concentrations for groups of materials with similar toxicological effects and/or physicochemical properties.” The agency’s report focuses on the assessment of typical microscale airborne particles and engineered nanomaterials by possible health impact and explores how engineered nanomaterials can be grouped into categories based on the degree to which their effects may harm worker health.

The report is divided into two parts: the first part, the user guide, focuses on tools for gathering and assessing information on OELs or bands for engineered nanomaterials, while the second part outlines the development of the methods for grouping engineered nanomaterials. Part II of the report also discusses the technical basis for the categorical OELs or OEBs described in Part I, the user guide. NIOSH describes the target audience of the report as occupational safety and health practitioners, including industrial hygienists, who use scientific information and tools to assess workplace safety and health.

NIOSH has opened a comment period for stakeholders and others to review and provide feedback on the draft report. The authors seek technical review on issues such as whether the draft document adequately describes the development of a framework for categorizing engineered nanomaterials by potential occupational health hazard from inhalation exposure and if a revision to current OEB guidance is needed to incorporate a new, more stringent “band F.” A notice in the Federal Register provides a full list of questions for those reviewing the draft report, which can be downloaded as a PDF from Regulations.gov. Comments are due by Sept. 13, 2021.