Nanoparticle Monitoring in Occupational Environments – Comparing and Contrasting Measurement Metrics
There is increasing commercial development of nano-scale materials, structures, and devices that take full advantage of the unique physical, chemical, and biological properties of these materials. The occupational health risks associated with the manufacturing and use of nanoparticles are not clearly understood. No government regulations or workplace exposure limits exist for exposure to nanoparticles. Nano-scale materials behave differently than larger particles. Nanoparticles occur in much greater numbers, have far more surface area, and have negligible mass in comparison to larger particles. Exposure to nanomaterials may occur through inhalation, dermal contact, or ingestion. Traditional workplace exposure aerosol limits are based on mass per unit volume (e.g., mg/m3 or µm/m3). A growing number of experts agree that number concentration, size distribution, and surface area should be measured instead of mass. The presentation provides a brief introduction to nanotechnology and discusses the limits of traditional industrial hygiene aerosol measurements for nanoparticles. The presentation concludes by comparing alternate measurement metrics and instrumentation for measuring nanoparticles when no workplace exposure limits have been established.