Nanopollutants change blood vessel reactivity - sunscreen, cosmetics, pharmaceuticals

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Nanopollutants change blood vessel reactivity.

<http://www.sciencenews.org/view/generic/id/339240/title/Nanopollutants_change_b\

lood_vessel_reactivity>

Exposure to nano-sized particles can impair the responsiveness of very

tiny blood vessels, new animal studies show.

Vessels called arterioles don't dilate or constrict appropriately after

recent nanoparticle exposure. The changes are small " but equate to a

level of impairment that would preclude affected tissues from

functioning normally, " says microvascular physiologist

Nurkiewicz of West Virginia University in town.

His team described new experiments March 13 at the Society of Toxicology

annual meeting.

The West Virginia researchers " have a unique set of findings that are

pretty powerful, " says Carll, a toxicologist at the University of

North Carolina at Chapel Hill. Their data " offer further demonstration

that air pollutants can impair cardiac function. "

In one set of tests, physiologist Knuckles of West Virginia

University exposed rats to airborne titanium dioxide nanoparticles ---

spheres 100 billionths of a meter across --- for four hours on two

consecutive days. The common material appears in a range of materials,

including sunscreen and cosmetics. The pollutant doses, though not in a

range considered toxic, were high enough to probe the possible effects

of occupational exposures to such engineered materials and

nano-pollutants associated with mountaintop mining....

In another experiment, rats inhaled or ingested particles known as

multi-walled carbon nanotubes. Made from rolled up sheets of carbon,

these tubes are about 50 billionths of a meter across and being explored

for use in delivering drugs via the nose, mouth or injections. As with

the nanospheres, the nanotubes made it harder for arterioles to dilate.

The nanotubes also exaggerated constriction when the body commanded

arterioles to reduce blood flow....

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Altered vascular phenotype in autism: correlation with oxidative stress.

<http://www.ncbi.nlm.nih.gov/pubmed/16908745>

Yao Y, Walsh WJ, McGinnis WR, Praticò D.

Arch Neurol. 2006 Aug;63(8):1161-4.

pdf here

<http://archneur.ama-assn.org/cgi/pmidlookup?view=long & pmid=16908745>

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T.R. Nurkiewicz et al.

Thinking outside the lung: Alternate routes of nanoparticle exposure

(abstract #924). Society of Toxicology annual meeting, March 13, 2012,

San Francisco.

S. Casinghino and M.A. Dobrovolskaia.

Nanoparticles for drug delivery: Interactions with the immune system

(abstract #818). Society of Toxicology annual meeting, March 12, 2012,

San Francisco.

M. Dobrovolskaia.

Immunological properties of engineered nanoparticles

(abstract #819). Society of Toxicology annual meeting, March 12, 2012,

San Francisco.

A.A. Shvedova.

Recognition of nanoparticles by macrophages --- from principles to

consequences and toxicity

(abstract #821). Society of Toxicology annual meeting, March 12, 2012,

San Francisco.