Concerns of nanotechnology-toxicity, benefits, challenges and future of nanotechnology

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Concerns of nanotechnology-toxicity, benefits, 

challenges and future of nanotechnology

Toxicity

          
There are mounting ecological concerns associated with nanotechnologies. Nanomaterials are introducing new and unexpected forms of pollution. The size, dissolvability and other novel characteristics of nanomaterials enable them to readily contaminate soils, waterways and food chains, posing new and little understood ecological risks. For example, antimicrobial properties of nanoparticles are able to shift into microbial populations—disrupting signals between nitrogen-fixing bacteria and plant hosts—with negative impacts for entire ecosystems. Nanoparticles can also transport other contaminants. Studies with fish demonstrate titanium dioxide can significantly increase cadmium accumulation. Nanoparticles can also bioaccumulate with recent findings demonstrating that carbon nanotubes are taken up by microbial communities and root systems, thereby concentrating up the food chain.

Tiny particles which, because of their small size, are able to travel very far into the environment. These particles will act in the environment or what chemical reactions they will trigger on meeting other particles. But mostly, the concern is for the lack of research into nanotechnology's potential threats   

          Nanoparticles gain ready access to the blood stream after being inhaled, while some can directly penetrate the skin. Scientific evidence demonstrates nanoparticles are able to cross-cellular barriers (including the stomach wall), increasing absorption rates and bioavailability. There is also evidence demonstrating nanoparticles are cytotoxic (i.e. toxic to cells). Meanwhile, carbon nanotubes (used in food packaging materials) have been likened to asbestos, with evidence demonstrating exposure may lead to mesothelioma, or lung cancer, in test mice. It is also possible that nanoparticles in food packaging materials may migrate into food it comes into contact. This is cause for alarm; given research into a range of nanoparticles that are widely used in food packaging (including nano silver, nano zinc oxide and nano chlorine oxide) demonstrate specific adverse health impacts—with tests on nano zinc oxide producing damaging health impacts in mice and rats, as well as being toxic to human cells, even at very low concentration.

Weapons are an obvious negative use of nanotechnology. Simply extending today's weapon capabilities by miniaturizing guns, explosives, and electronic components of missiles would be deadly enough. However, with nanotechnology, armies could also develop disassemblers to attack physical structures or even biological organism at the molecular level. A similar hazard would be if general purpose disassemblers got loose in the environment and started disassembling every molecule they encountered. This is known as "The Gray Goo Scenario." Furthermore, if nanomachines were created to be self replicating and there were a problem with their limiting mechanism, they would multiply endlessly like viruses. Even without considering the extreme disaster scenarios of nanotechnology, we can find plenty of potentially harmful uses for it. It could be used to erode our freedom and privacy; people could use molecular sized microphones, cameras, and homing beacons to monitor and track others.

Benefits

          Along with all the obvious manufacturing benefits, there are also many potential medical and environmental benefits. With nanomachines, we could better design and synthesize pharmaceuticals; we could directly treat diseased cells like cancer; we could better monitor the life signs of a patient; or we could use nanomachines to make microscopic repairs in hard-to-operate-on areas of the body. With regard to the environment, we could use nanomachines to clean up toxins or oil spills, recycle all garbage, and eliminate landfills, thus reducing our natural resource consumption.

Future of nanotechnology

Nano Farming:     The agri-chemical and information technology industries have shifted down to the nano-scale to produce new agricultural chemicals, seeds, and livestock with novel functions and capabilities, as well as new systems of farm monitoring and management.

Nano pesticides including microcapsules that contain pesticides engineered to break open in the alkaline conditions of an insect’s stomach. This will enable the more targeted delivery of pesticides. The convergence of nanotechnologies with biotechnology, also provides industry with new tools to modify genes and even produce new organisms. For example, nanobiotechnologies enable nanoparticles, nanofibres and nanocapsules to carry foreign DNA and chemicals that modify genes. In addition to the re-engineering of existing plants, novel plant varieties may be developed using synthetic biology; a new branch of technoscience that draws on the techniques of genetic engineering, nanotechnology and informatics. Recently, researchers completely replaced the genetic material of one bacteria with that from another—transforming it from one species to another. These technologies clearly up the ante, increasing both the opportunities and risks offered by each of these technologies in isolation.

NanoFood: Nanotechnologies are being used to manufacture entirely new foods. These include ‘smart’ foods—nutritional profiles that respond to an individual’s allergies, dietary needs or food preferences. While such designer food sounds like the stuff of fantasy, nanotechnologies make them scientifically possible. Nanotechnology is also being used to alter the properties and traits of food; including its nutrition, flavor, texture, heat tolerance and shelf life. For example, breakthroughs in the manufacture of low fat and low-calorie food that retains its rich and creamy taste and texture, applying this to a range of very low-fat ice-creams, mayonnaise and spreads . Meanwhile, food companies are using microcapsules to deliver food components such as omega 3-rich fish oil. The release of fish oil into the human stomach is intended to deliver claimed health benefits of the fish oil, while masking its fishy taste.

Nano Food Packaging: Nano food packaging is the most commercialized of the agri-food nanotechnologies. Nano packaging materials include barrier technologies, which enhance the shelf life, durability and freshness of food—or at least slow the rotting process.

A nano titanium dioxide plastic additive that reduces UV exposure that they claim will minimize damage to food contained in transparent packaging. Nano packaging is also being designed to enable materials to interact with the food it contacts; emitting antimicrobials, antioxidants, nutraceuticals and other inputs. This ‘smart’ or ‘active’ packaging, as manufacturers brand it, is being developed to respond to specific trigger events. For example, packaging may contain nanosensors that are engineered to change color if a food is beginning to spoil, or if it has been contaminated by pathogens. This technology is already being used with carbon nanotubes incorporated into packaging materials to detect microorganisms, toxic proteins and food spoilage.

Social Transformations From Nano-foods

          The broad range of nanotechnological innovations is being used to support the continuation of the dominant industrial food system; despite the obvious social, economic and ecological limits of this system. In many instances, nano innovations offer short term techno-fixes to the problems facing modern industrial agriculture and food systems, or introduce new efficiencies within large-scale systems. There are many parallels between nano-food innovations and the introduction of genetically engineered foods. While promising to ameliorate some of the health and ecological problems associated with industrial food production, processing and distribution, they also threaten to introduce new dangers to the environment and human health. At the same time, these applications threaten to further concentrate corporate ownership and control of large sections of food production systems and markets, and to increase inequalities and power imbalances across the food system.

          Nanotechnologies are likely to extend some of the adverse impacts associated with the introduction of earlier technologies as well, including genetic engineering. For example, it can be expected that nanotechnology will support large-scale, capital and chemical-intensive production, given that nano-pesticides and nanosensors are likely to deliver the greatest benefits to large-scale farming operations. They are also likely to support the further expansion of chemical-intensive, mechanized and automated farming operations. Given patterns of corporate ownership and high levels of concentration across the nano industries, the adoption of these technologies is also likely to further erode farmers’ autonomy and control over their farm operations.

        Labs-on-a-chip are pocket-sized laboratories. They can be used for analyzing biopolymers and also for research and for manipulating cells. They are expected to play an important role in the further development of biosensors for the detection of pathogenic bacteria. In due course, simple analyses can be made in the patients’ homes and carried out by the patients themselves. Researchers are currently working on the development of a lab-on-a-chip for measuring lithium concentrations in the blood.