Biomedical Engineering Reference
In-Depth Information
regard to such conclusions, based on unpublished propriety research, due
diligence is needed in tracing assertions back to primary sources.
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In 2007, the United States listed gold and silver nanoparticles among a
number of new chemicals and materials that the FDA had asked the National
Toxicology Program (NTP) to study. This will seek to determine whether
their use causes specific health problems. The NTP should test gold nanopar-
ticles and determine what types of tests are warranted.
3.3 Summary
Although bulk gold is considered to be intact and the most inert material
used safely for centuries, in addition to being considered the most nontoxic
material by chemists, nanoparticulated gold poses certain risks for human
health, mainly due to the many aspects of modifications enabled by nano-
technology. Particle shape and the solvent used to obtain gold nanoparticles
present some danger to safety. Experiments have shown that gold nanopar-
ticles can result in uptake via the relevant exposure routes. Their properties
and the cell types used for their exposure are likely to influence the uptake,
subcellular distribution, and toxicity of gold nanoparticles. That is why sci-
entists work to obtain safe and nontoxic forms of nanoparticle gold—exam-
ples include ultrasound exposure for the production of gold nanoparticles
and the use of certain bacterial strains capable of producing gold nanopar-
ticles that are free of solvent. However, the charge and particle shape char-
acteristics remain a cause for concern with regard to consumer safety. From
a thorough analysis of the scientific literature, investigating the divergent
features of gold nanoparticles, the concept that some gold nanoparticles pose
human health risks can be obviated, as information about the exact physical
and chemical properties of gold nanoparticles used in certain cosmetic or
health-care products need to be strictly regulated. Until now, relevant control
mechanisms are under development. As cosmetic products achieve market
acceptance earlier than drugs, there are currently available personal care
items in the market that are positioned as nanoparticle gold containing and
safe. Actually, many of them must be safe, as manufacturers sell nanogold-
containing fluids, the chemical and physical properties of which are pre-
sented in product certificates.
However, investigations on metal particulates are still in their infancy
at this time and have concentrated on revealing the toxicity, safety, tissue
distribution, antibacterial properties, and cellular uptake of gold nanopar-
ticles. Consequently, more comprehensive studies are required to more fully
understand the risks associated with metal particulate exposure.
Inevitably, any emerging technology requires extensive safety assess-
ment before coming to market, including diagnostics, medications, and
