Nanotechnology Podium Session Provides New Answers
Nanotechnology is once again a hot topic at the American Industrial Hygiene Association's annual conference and expo. Today's "Nanoparticle Assessment and Control" Technical program (PO 101), sponsored by the Nanotechnology Working Group, was nearly filled to capacity as attendees gathered around to listen as several industry professionals and researchers discussed their latest scientific findings at the conference being held in Minneapolis.
Michael Weeks, ENVIRON International Corp., discussed nanomaterial exposure assessment and control validation using tracer gas technologies.
Using tracer gas is a good way to measure exposure because nanosized particles behave like a gas when airborne, Weeks said. Some gases that could be used include sulfur hexafluoride, carbon dioxide, freons, and many others depending on application and need.
The biggest issues surrounding nanoparticle exposure, Weeks said, are the lack of knowledge regarding toxicity, lack of nanomaterial specific standards, and uncertainty of measurement techniques.
Some of the biggest reasons that nanotechnology has grown so much in popularity, Weeks added, is because of the common perception that this new science will change life as we know it. Also, he said, the media tends to magnify the risks involved.
Despite the many unknowns, Weeks emphasized that the responsibilities of industrial hygienists have not changed; they must still protect employees from hazards, both known and unknown, using proven and sophisticated techniques.
To reduce the hazards, Weeks listed five steps:
- Identify health hazards
- Identify tasks and workers
- Control planning
- Control implementation
- Periodical re-evalution
Kwangseog Ahn, University of Massachusetts Lowell, reaffirmed through his demonstration that HEPA filtration is a viable method of removing nanoparticles from the air. Fabric filters were shown not to be an effective alternative; however, since fabric filters are reusable and HEPA filters are not, it was recommended that IH professionals employ a two-stage collection system in which a fabric filter is used followed by a HEPA filter, in order to elongate the HEPA filter's life.