Nanotechnology, what is it? First of all, let us define nanotechnology so that one can better understand what the concept of it is. “Nanotechnology, also called molecular manufacturing, is ‘a branch of engineering that deals with the design and manufacture of extremely small electronic circuits and mechanical devices built at the molecular level of matter.’12 The goal of nanotechnology is to be able to manipulate materials at the atomic level to build the smallest possible electromechanical devices, given the physical limitations of matter. Much of the mechanical systems we know how to build will be transferred to the molecular level as some atomic analogy.”  So nanotechnology is on the scale of 100 nanometers or less, which gives engineers access to tools on the atomic level.
Figure: Displays different nanotechnologies 
What are the Benefits from Nanotechnology? If nanotechnology keeps being researched upon then access to some benefits may open up such as:
So basically, through the use on nanomachines or nanorobots, one “…could better design and synthesize pharmaceuticals[,]” “…directly treat diseased cells like cancer[,]” “…better monitor the life signs of a patient[,]” “or…make microscopic repairs in hard-to-operate-on areas of the body.” Other things that one could be able to do with nanotechnology is the “…use [of] nanomachines … [is] clean up toxins or oil spills, recycle all garbage, and eliminate landfills, thus reducing our natural resource consumption.”
However, not only would one have access to those potential benefits, but newer dangers would emerge such as:
So with the potential of having weapons or explosives made at the molecular level, it would mean that if it fell into the wrong hands such as terrorists, they would be able to wreak havoc anywhere in the world from the molecular level. As a result, this would mean that new security measures would have to be developed and thus, it may be the end of our privacy and freedom that we have today. This is because if one is to combat weapons at the molecular level, then surveillance at the molecular level would have to be made to constantly scan and watch from any area which could mean that if used incorrectly, then “… [P]eople could use molecular sized microphones, cameras, and homing beacons to monitor and track others.”
Ethical Issues Some of the ethical issues that emerge from nanotechnology (NT) fall under the following categories:
Equity “…NT, were it to develop in the way it ought, might ultimately be of most value for the poor and sick in the developing world. At the Johannesburg summit, the main issues for developing countries were poverty reduction, energy, water, health, and biodiversity. NT has the potential to make a positive impact on all of these if its risks either do not materialize or are appropriately managed. The poor could benefit from NT, for example, through safer drug delivery, lower needs for energy, cleaner energy production, and environmental remediation. It is also possible that health could be improved by better prevention, diagnosis, and treatment. One of the biggest health problems in developing countries is trauma, especially from road traffic accidents, and absence of rehabilitation facilities : better nanomaterials for making safer t[i]res, or NT-based scaffolds to grow bone  may be extremely important, especially if the promise of mass production at very low cost materializes.” 
What this is saying is that not only will developed countries benefit from nanotechnology, but developing countries will either benefit more or the same as well.
Privacy and security “NT is capable of dramatically improving surveillance devices, and producing new weapons. How would individual privacy be protected if near-invisible microphones, cameras, and tracking devices become widely available? Will these new technologies increase security or add to the arsenal of bio- and techno- or even nano-terrorism? Who will regulate the direction of research in defensive and offensive military NT? How much transparency will be necessary in government and private NT initiatives to avoid misuses? There are also very interesting legal questions  involving monitoring, ownership, and control of invisible objects .” 
The issue here is that while surveillance systems would be considerably improved to keep our defenses up by giving the military the means to monitor an enemy threat, at the same time, that technology could be used against us such that our privacy would no longer be so secure and as a result, identity theft could occur more.
Environment “NT has already generated novel types of matter such as fullerenes and carbon nanotubes. Where do these and other nanomaterials go when they enter the environment and what are their effects? This year, the US environmental protection agency (EPA) has added the funding of research projects that explore potential environmental dangers of NT to its list of priorities.”
Basically, the issue here is that not enough research has been given to determine the effects of nanotechnology on the environment which means that we are unsure of any harm that may occur from NT materials which are produced or used.
Human or machine? “Some avenues of research in NT include the incorporation of artificial materials or machines into human systems, as is beginning to happen with implanted computer chips . The modification of living systems is met with great s[k]epticism by much of society. How acceptable will technologies such as implantable cells and sensors be for the general population? What are its implications and what are our limits?”
Two issues that arise from this ethical issue are about how far are we willing to go to replace human parts with robotic parts and will this seem like God is being put out of business? This would cause a lot of fuss from several religious parties.
Conclusion Not only does nanotechnology offer great potential that can benefit humankind but at the same time it can cause severe danger as well. So what I think is that we should not stop research on nanotechnology. Instead we should create some ethical guidelines and policies so that we can reduce some of the ethical issues that can occur and to insure that the technology does not become potentially harmful. Also, “…nanomachines should NOT be designed to be general purpose, self replicating, or to be able to use an abundant natural compound as fuel. Furthermore, complex nanomachines should be tagged with a radioactive isotope so as to allow them to be tracked in case they are lost.”
 http://www.theage.com.au/articles/2004/12/08/1102182359368.html  http://www.treehugger.com/files/2007/05/nanotech_environment.php  http://cnst.rice.edu/nano.cfm  Chen, Andrew. “The Ethics of Nanotechnology.” American Institute of Biological Sciences. March 2002. 13 Dec. 2007.
 Mnyusiwalla, Anisa. Daar, Abdallah S. and Singer, Peter A. “‘Mind the gap’: science and ethics in nanotechnology.” Institute of Physics Publishing. 13 Dec. 2007.