Report Outlines Occupational Sampling for Nanomaterials

Practical approaches for sampling engineered nanomaterials (ENMs) in the workplace are outlined in a new NIOSH technical report. ENMs, the report explains, are “a diverse group of materials that have at least one dimension in the size range of 100 nanometer (nm) or less.” ENMs are potentially hazardous because some substances have been found to be more toxic in microscale forms than at larger scales. As ENM production is increasing and these materials are being incorporated into more products, NIOSH has identified “a clear need to develop, implement, and apply a suitable strategy for occupational risk assessment and management” of ENMs.

To support an ENM management strategy, the report outlines steps for conducting workplace sampling of three types of ENMs that have NIOSH recommended exposure limits: airborne carbon nanotubes and nanofibers (CNTs and CNFs), silver, and titanium dioxide (TiO₂). Another section of the report discusses recommendations for exposure sampling of ENMs lacking NIOSH RELs. Since no single instrument or analytical technique can assess occupational exposure for all ENMs, NIOSH recommends combinations of instruments and measurement techniques to collect data to characterize ENM exposures.

Studies in rats and mice have shown that inhalation of CNTs and CNFs, silver nanoparticles, and TiO₂ nanomaterials causes a range of health effects that particularly impact lung function. Occupational exposures to CNTs and CNFs in workers are also “associated with biomarkers of early effect for fibrosis, inflammation, oxidative stress, and cardiovascular responses,” the report states.

The report can be downloaded for free from NIOSH’s website.