Nanotechnology is the development and use of techniques to study physical phenomena and construct structures in the physical size range of 1-100 nanometers (nm), as well as the incorporation of these structures into applications . Nanotechnology is a dynamic field that is constantly evolving. Nanotechnology impacts all areas of our lives. For instance, nanotechnology has had an impact in the areas of electronics, foods, medicine, medical procedures, energy, computer, information technology, and communications. In addition to the benefits of nanotechnology, we must be alert to cautions and risks associated with nanotechnology. Why should we exercise caution? Studies have shown issues of concern; such as, incursion, retention, and the movement of nanoparticles within living beings and their tissues. For example, titanium dioxide nanoparticles that were inhaled by animal test subjects were later found on the luminal side of airways, and in the major lung tissue compartments and cells . In this article, we will look at areas of caution and risk in the development and application of nanomaterials.
Two areas of significance are the impact of nanomaterials on the human body, and on the environment. There have been a few studies conducted to determine the impact of nanomaterials on the human body; specifically, if ingested. However, there have not been enough studies conducted to give indisputable conclusions on either the impact of nanomaterials on the human body or the environment. Specifically, we will consider risks in relation to the human body.
One study was conducted on the human body, in order to determine if nanomaterials could pass through the placenta to a fetus. The researchers determined that depending on the size of the nanoparticles; the particles could pass through the placenta to the fetus . In another study, consumer spray products which contained nanomaterials were analyzed in order to detect the presence and possible dispersal of the nanoparticles once the sprays were used. The researchers found that the nanoparticles were present and could potentially be inhaled by individuals. The nanoparticles that were detected ranged from 14 nanometers to 20 micrometers in size [2, 4]. The true question is whether the inhalation and ingestion of the nanomaterials are harmful to humans, animals, and the environment.
In light of the risks and cautions that are mentioned by the studies that have been conducted up to this point; efforts are being made to address the concerns related to the development and use of nanomaterials. For instance, The European Food Safety Authority has provided guidance on, 1) the physic-chemical characterization requirements of engineered nanomaterials, and 2) testing approaches to identify and characterize hazards arising from nanomaterials . In addition, The Institution of Occupational Safety and Health and the United Kingdom NanoSafety Partnership Group produced a publication geared towards reducing health risks associated with working in nanotechnology . Also, a National Research Council report, A Research Strategy for Environmental, Health, and Safety
Aspects of Engineered Nanomaterials, (2012) identified four search categories that should be addressed within 5 years:
- Identify and quantify nanomaterials being released and populations and environments being exposed.
- Understand processes that affect both potential hazards and exposure.
- Examine nanomaterials interactions in complex systems ranging from sub cellular to ecosystems.
- Support an adaptive research and knowledge infrastructure for accelerating progress and providing rapid feedback to advance research .
As is evident from this brief look at the cautions and risks associated with the research, development, and application of nanotechnology and its various nanomaterials; there is still much to be learned and many benefits to be gained from nanotechnology.
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