Biomedical Engineering Reference
In-Depth Information
nano-products are already on the market and enjoying commercial
success. For example, nanoparticles are used in some sunscreens
to relect and absorb ultraviolet (UV) light; the football-shaped
buckminsterfullerene (C
60
) and its analogs show great promise as
lubricants and, thanks to their cage structures, as drug delivery
systems [8, 31].
Applications of nanotechnologies in medicine are especially
promising in the long term. These can be expected to enable drug
delivery targeted at speciic sites in the body so that, for example,
chemotherapy is less invasive [8]. Nanotechnology is expected to
lead to stronger, longer-lasting implants; sensors that can be used to
monitor aspects of human health; and improved artiicial cochleae
and retinas. However, many of these applications will not be realized
for at least 10 years, partly because of the rigorous testing and
evaluation that will be required. Antimicrobial wound dressings
are already on the market in the United States. These dressings use
nanocrystalline Ag to provide a steady dose of ionic Ag to protect
against secondary infections and are claimed to be effective against
150 different pathogens.
Little research has been carried out on the toxicity of
manufactured nanoparticles, but we can learn from studies on the
effects of exposure to mineral dusts in some workplaces and to the
nanoparticles in air pollution. Considerable evidence from industrial
exposure to mineral dusts demonstrates that the toxic hazard is
related to the surface area of the inhaled particles and to their surface
activity. Epidemiological studies of urban air pollution support the
conclusion that iner particles cause more harm than coarser ones
— diesel PM
10
pollution is implicated in heart and lung disease and
asthma, particularly in susceptible people.
There is practically no information on the environmental impacts
of nanoparticles. More research on their properties and effects is
necessary. It is time to look at the toxicity, epidemiology, persistence,
and bioaccumulation of manufactured nanoparticles, including their
exposure pathways.
References
1. Agheli, H., Malmström, J., Hanarp, P., and Sutherland, D.S. (2006).
Nanostructured biointerfaces,
Mater
.
Sci
.
Eng
.,
C
,
26
, pp. 911−917.
