Nanoparticles in occupational environment: Insights for detection, modeling, and risk assessment
Andrey Korchevskiy, Daniel Hall, Matthew Hull, Cary Hill, & Steven Trammell
Toxicity of tiny particles became a matter of toxicological concern many decades ago. Small size of a particulates sometimes serves to decrease the inhalation hazard, because significant fraction of such particles would not be retained in the body for long time. However, the smallest particles can also penetrate deep and interact with the sensitive cellular structures. Sometimes, nanoparticles of the same chemical composition are considered much more toxic than their larger analogies. Nanoparticles are widely spread in occupational environments; however, the related industrial hygiene interventions are often limited because of the difficulties in recognizing the hazard, measuring the exposure concentrations, and assessing the risks. This issue is especially concerning for the technologically advanced industries, including semiconductor facilities where different types of nanoparticles and fibers can be expected as a part of workers’ exposure. This PDC will take participants for an intensive, half-a-day ride, exploring how to address the occupational health and industrial hygiene issues related to particles and fibers of extremely small size. The types of nanoparticles and their sources in semiconductor facilities will be identified and characterized.
We will discuss techniques and tools that may be deployed at the semiconductor facilities to assess exposures to nanoparticles in the workplace, from cost-effective personal exposure detectors to robust analytical suites capable of discerning great detail regarding nanoparticle size, concentration, and composition. It will be also demonstrated how air dispersion modeling, including computational fluid dynamics (CFD) software, can be used to assess the exposure to nanoparticles from various types of equipment. The participants will be lead through examples showing how industrial hygienists and environmental professionals can use CFD to assess and prevent exposure to hazardous particulates.
At the end of this session, attendees will be equipped with basic knowledge and starting resources for determining nanoparticle exposure as well as avenues for guidance from experts. The audience will also learn how to evaluate toxicity of nanoparticles in the situations when occupational exposure limits are established only for certain types of the agents (like carbon nanotubes and titanium dioxide). The “scale of toxicity” approach will be introduced to help with exposure banding for the purposes of practically oriented and scientifically based risk assessment.