This section provides environmental, health and safety guidance to researchers working with engineered nanomaterials in Stanford University laboratories. It is intended to supplement the requirements of Stanford University’s Chemical Hygiene Plan and its companion Laboratory Safety Toolkit.

As the scientific community continues to gather data to assess the potential health and safety risks associated with engineered nanomaterials and more information becomes available, these guidelines may be updated. Until more is known about the possible risks of nanomaterials, it is prudent and appropriate to take a precautionary approach and to utilize good laboratory safety practices when working with these materials.

Action items for faculty working with or creating engineered nanomaterials

• Review the General Principles and Practices for Working Safely with Engineered Nanomaterials document.
• Instruct all research personnel in your lab to follow the work practices described in the document.
• Create standard operating procedures (SOPs) for processes and experiments involving nanomaterials using the guidance in the SOP section. Priority for SOP development should be given to those operations where there is higher risk of exposure (e.g. manipulation of nanoparticles in a gas stream or work with dry dispersible nanoparticles).

What are nanomaterials?

Nanomaterials are defined as materials with at least one external dimension in the size range from approximately one to 100 nanometers. Nanoparticles are objects with all three external dimensions at the nanoscale.¹ Nanoparticles that are naturally occurring (e.g. volcanic ash or soot from forest fires) or are the incidental byproducts of combustion processes (e.g. welding, diesel engines) are usually physically and chemically heterogeneous, and are often termed ultrafine particles.

Engineered nanoparticles are intentionally produced and designed with very specific properties related to shape, size, surface properties, and chemistry. These properties are reflected in aerosols, colloids, or powders. Often, the behavior of nanomaterials may depend more on surface area than particle composition itself. Relative surface area is one of the principal factors that enhance reactivity, strength, and electrical properties.

Engineered nanoparticles may be bought from commercial vendors or generated via experimental procedures by lab researchers. Examples of engineered nanomaterials include carbon buckeyballs or fullerenes, carbon nanotubes, metal or metal oxide nanoparticles (e.g. gold or titanium dioxide), and quantum dots, among many others.