Ultrafine particle

Ultrafine particles (UFPs) are particulate matter of nanoscale size (less than 0.1 μm or 100 nm in diameter).[1] Regulations do not exist for this size class of ambient air pollution particles, which are far smaller than the regulated PM10 and PM2.5 particle classes and are believed to have several more aggressive health implications than those classes of larger particulates.[2] Although they remain largely unregulated, the World Health Organization has published good practice statements regarding measuring UFPs.[3]

There are two main divisions that categorize types of UFPs. UFPs can either be carbon-based or metallic, and then can be further subdivided by their magnetic properties. Electron microscopy and special physical lab conditions allow scientists to observe UFP morphology.[1] Airborne UFPs can be measured using a condensation particle counter, in which particles are mixed with alcohol vapor and then cooled, allowing the vapor to condense around them, after which they are counted using a light scanner.[4] UFPs are both manufactured and naturally occurring. UFPs are the main constituent of airborne particulate matter. Owing to their large quantity and ability to penetrate deep within the lung, UFPs are a major concern for respiratory exposure and health.[5]

  1. ^ a b S. Iijima (1985). "Electron Microscopy of Small Particles". Journal of Electron Microscopy. 34 (4): 249.
  2. ^ V. Howard (2009). "Statement of Evidence: Particulate Emissions and Health (An Bord Plenala, on Proposed Ringaskiddy Waste-to-Energy Facility)" (PDF). Durham Environment Watch. Archived (PDF) from the original on 2012-03-31. Retrieved 2011-04-26.
  3. ^ url = https://iris.who.int/handle/10665/345334
  4. ^ John D. Spengler, John F. McCarthy, Jonathan M. Samet (2000). Indoor Air Quality Handbook. Mcgraw-hill. ISBN 978-0074455494.{{cite book}}: CS1 maint: multiple names: authors list (link)
  5. ^ T. Osunsanya; et al. (2001). "Acute Respiratory Effects of Particles: Mass or Number?". Occupational & Environmental Medicine. 58 (3): 154–159. doi:10.1136/oem.58.3.154. PMC 1740106. PMID 11171927.