Nanoparticles and Health. Michael T. Kleinman Department of Community and Environmental Medicine University of California, Irvine. Particle Scale. PM 10. Ultrafine. Respirable. PM 2.5. Nanoparticles. 10 m m. 1 m m. 1 nm. 10 nm. 100 nm. Definitions- Particle Size.
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Michael T. Kleinman
Department of Community and Environmental Medicine
University of California, Irvine
Interparticle Forces And Surface Chemistry Will Be Influenced By Size And Whether Particles Are Individual or Aggregates & Agglomerates
Van der Waals (cohesive force α 1/d**2)
Equivalent dia. ~2 x
Settling velocity ~3-4 x
Equivalent diameters of 10-1000x are common
Nanoparticles are far to useful NOT to enter the human environment!
Once an early biomarker of a disease or dysfunction is identified, then scientists can use targeted pharmaceutical or gene therapy to correct the faulty components.
Carbon Nanotubes Will Be Used In Electronics Applications in the environment and in people
Source: Scientific American- Illustration: RICHARD E. SMALLEY, Rice University
Electron micrographs demonstrating effects of different sized particles in RAW 264.7 cells treated
with USC-Jan 02 CAPs for 16 hr. (A) and (B) Untreated RAW 264.7 cells. (C) and (D) RAW 264.7 cells exposed
to coarse particles. (E) and (F) RAW 264.7 cells exposed to fine particles. (G) and (H) RAW 264.7 cells
exposed to UFPs. Notice damage to cristae as well as the presence of particles (P) inside mitochondria (M)
in UFP- or fine + UFP-exposed cells.
Hepatocytes were labeled by endocytosis of EGF-coated red QDs
A & B Labeled Hepatocytes on Day 1.
C & D Hepatocytes were reorganized by Day 7 but still identified by label.
D Albumin production (marker for hepatocyte function) same as controls.
LESSON LEARNED: Nanomaterials may be safe under laboratory conditions but not under some environmentally relevant conditions.
(A) Hepatocyte viability assessed by mitochondrial activity of QD-treated cultures vs. untreated controls. Thirty minutes of exposure to air while TOPO-capped renders QDs highly toxic at all concentrations tested. Ultraviolet light exposure increases toxicity with increasing time and QD concentration
Handling nanotube material the handling of unrefined SWCNT- Andrew Maynard et al.
Raw single walled nanotube material
Characteristics of airborne ‘nanotube’ particle the handling of unrefined SWCNT- Andrew Maynard et al.
Nano-SiO2 is less inflammatory than Min-U-Sil
Pigmentary & Nano-TiO2 are not different
Most of the initial reports (in the media) have been positive; however, we should not forget that given the nature of nanoparticles, not all nanomaterials will be benign.
—Kenneth OldenWHERE DO WE STAND?