User:The Overlooker/Nanowiki

Safety of Nanotechnology

Nanotechnology is a very new branch of science and products incorporating nanotechnology are being brought to the consumer market in record numbers. While products containing nanotechnology have great advantages, there has been little research and even less reported data on the long term consequences of these extremely small particles involving human health, society, and the environment.

Abstract

The research of nanotechnology is progressing at an astronomical rate. Products incorporating nanotechnology are being introduced to the consumer market almost as fast. Nanotechnology allows products to be more effective and/or more efficient and in some instances allow products to do things that ordinarily not be possible. Most of the research done with nanotechnology involves synthesis and characterization; much less research has been done on the environmental effects and physiological effects on the human body. Even slower is the ability for the government to enact laws and regulations. Slowly, evidence has been mounting that nanoparticles can cause harm to the human body and questions have been raised on how long they can persist in the environment. In the quest for ever tightening regulations however, the advantages of nanoparticles are almost becoming a requirement to meet the demands of 21st century materials. The real question is whether the pros of using nanotechnology outweigh the possible negative impacts that its use could be having on our environment and health.

Introduction

So what exactly is nanotechnology? To start off, nano is referring to the size of the “technology”, with one dimension of the object being one to one hundred nanometers long. A nanometer is defined as 1×10⁻⁹ meters, this is the same as dividing up 1 meter, which is about 3 feet, one billion times. For comparisons sake, human hair ranges from 18,000 to 80,000 nanometers thick[1]. The technology part refers to anything and everything. Currently there are over 1,000 products advertised as products containing or utilizing nanotechnology[2]. These range from odor preventing socks to skin creams, and even clothes washers. But how safe are these products long term? This whole nanotechnology craze has an eerie similarity to the radioactivity craze that swept over the country almost a century ago. Irradiated water jugs promised to prevent acne and arthritis. It wasn’t soon before it was found out that regular exposure to radiation greatly increases the possibility of cancer.

Background

Diagram of an AFM.

The age of nanotechnology came to light in the 1980s with the advent of the scanning electron microscope. The scanning electron microscope made, for the first time ever, images of surfaces at the atomic level. This allowed scientists to view things in nanoscale, such as individual atoms, something that had previously been unheard of. Other advancements in the area of chemistry contributed to the foundation of nanotechnology. One such discovery that greatly increased interest in nanosized structures was the discovery of carbon fullerenes. These are the well known carbon soccer balls known as bucky balls and other spherical or egg shaped carbon cages. These fullerenes are rather similar to one of the most famous nanomaterials, carbon nanotubes.

How do nanoparticles work?

Nanoparticles work so well because of their extremely small size. They have an extremely high surface area which accelerates reactions. Particles that are nanosized behave differently than the sizes we are used to. For example gold, which we think of as a gold colored metal is a violet to light pink depending on size of the nanoparticles. Another while field of nanotechnology are nanomachines. These are little contraptions are built from individual atoms or molecules that accomplish a certain task. These tasks can be mechanical, chemical, or even electrical tasks.

Our stance

We believe that the benefits do outweigh the negative effects because nanotechnology has the potential to overcome the current health and environmental obstacles.

Argument

The controversy whether the benefits from applied nanotechnology outweigh the negative impacts on society and the environment is a complex issue on two main levels. First, nanoparticles provide advanced modification of everyday materials. Application of nanoparticles range from household consumables such as toothpaste to large-scale water-filtration that has a variety of uses in and of itself. The question is raised: if they were found to be dangerous, how would we limit their application when they are already deeply involved in much of industry and medicine? Second, nanoparticles provide a current source of income for the economy on a global scale that could help carry the people of the world to new heights in terms of renewable resources that have worth. If nanoparticles pose a threat to the environment and human health, how would limiting the use of nanotechnology affect the current global economy? The possible health and environmental effects are numerous. Hinds (1999) found that UFPs have longer lifetimes in the atmosphere, can be transported over thousands of kilometers, and remain suspended in air for several days.3 This presents a possibility that nanoparticles can adversely affect the environment by picking up pollutants from one environmental pocket and translocating the pollutants to other pocket environments (e.g. from soil systems to water systems). The adsorbed pollutants can then be released into the new environment depending on the pH of that environment. It is currently difficult to surmise what the many different types of effects nanoparticles could have on the environment due to a lack in proper research. Currently, nanoparticles have a wide spectrum of applications to the medical field. They allow for better diagnostics and cellular imaging by acting as fluorophores (molecules that fluoresce under ultra-violet light). In a study using mouse fibroblasts, Bruchez et al. (1998) showed that NP-based fluorescent labeling was better than conventional fluorophores. Nanoparticles are also applied to drug delivery. Various chemical processes in bacteria and multi-cellular organisms can be affected by nanoparticles due to their ability to easily pass through cell membranes and interact with biologically important molecules such as DNA and proteins. Research currently shows that titanium dioxide, a type of nanoparticle used in paint, sunscreen, and some foods, can pass through the air-water barrier in the lungs and enter the blood stream. Conclusion The worldwide market for products produced using nanotechnology is estimated to reach US$1 trillion by 2015 (Roco 2005).3 The U.S. Environmental Protection Agency, the International Life Sciences Institute Research Foundation, and the Risk Science Institute brought together experts in the fields of nanotechnology from academia and government to develop new toxicity screening, reporting, and hazard identification of engineered nanomaterials.3

References

1. Reviewing the Environmental and Human Health Knowledge Base of Carbon Nanotubes Author(s): Aasgeir Helland, Peter Wick, Andreas Koehler, Kaspar Schmid, Claudia Som Reviewed work(s):Source: Environmental Health Perspectives, Vol. 115, No. 8 (Aug., 2007), pp. 1125-1131Published by: Brogan & PartnersStable URL: http://www.jstor.org/stable/4626843 .

2. Health Sharpening the focus on occupational safety and health in nanotechnology Author(s): Paul Schulte, Charles Geraci, Ralph Zumwalde, Mark Hoover, Vincent Castranova, Eileen Kuempel, Vladimir Murashov, Harri Vainio, Kai Savolainen Reviewed work(s):Source: Scandinavian Journal of Work, Environment & Health, Vol. 34, No. 6 (December 2008),pp. 471-478Published by: the Scandinavian Journal of Work, Environment & Health, the Finnish Institute of Occupational Health, the Danish National Research Centre for the Working Environment, and the Norwegian National Institute of Occupational Health Stable URL: http://www.jstor.org/stable/40967745 .

3. Nanoparticles: Health Effects: Pros and Cons Author(s): Maureen R. Gwinn and Val Vallyathan Reviewed work(s):Source: Environmental Health Perspectives, Vol. 114, No. 12 (Dec., 2006), pp. 1818-1825Published by: Brogan & Partners Stable URL: http://www.jstor.org/stable/4119591