Benefits of nanoscience and nanotechnology have been carefully implemented in many areas of engineering to enhance the performance and quality of living conditions. Even though the novel technology offers enormous benefits, the serious concerns in that need to be addressed before commercializing the technology. Proper implementation of the technology needs careful assessment of the impact on environment, health hazards that may arise to the workers, users of the products and also to the environment. An attempt has been made to highlight the potential hazards of nanotechnology in some of the areas and the possible remedial measures, though the availability of the data to substantiate the claims are very much limited.
Nanotechnology employs "bottom up" as well as "top down" approaches to produce nanomaterials in all the three dimensions. Nanoparticles, nanotubes and carbon nanocrystals called Bucky Balls are now being manufactured in large quantities [1, 2, 3]. Quantum effects begin to dominate the behaviour of matters at the nanoscale and affect the optical, electrical and magnetic behaviours. Applications of nanotechnology in terms of nanofibres, nanoparticles, nanocomposites and nanotubes have been reviewed recently by many researchers [4, 5, 6, 7, 8]. Nanofibres, nanotubes and nano-particles for imparting functional finishes find increased applications in various forms of textile materials [5, 6, 7]. Though the advantages of the nanomaterials are unending, the potential risks or hazards to ecosystem or to the humans have drawn very little attention. Potential hazards exist in production of man made fibres where nanosized dope additives are mixed and, in the post manufacturing operations, where the continuous filaments are cut into staple fibres. The post spinning processes are capable of producing respirable fibre flocks, tiny fibres that can result in diseases related to lungs [4, 9].
Even though the nanomaterials appear to be a single class of material they differ in terms of size, shape, surface area, chemical compositions, biopersistance ; the possible environmental and health impact need to be assessed for each type of nanomaterial separately. Two factors that are responsible for occupational risk of nano-particles include size and massive surface area, which can absorb toxins and similar substances that can be transported into the body .
2.0 Potential Hazards
Proper implementation of nanotechnology increases the exposure to nanoparticles through various routes like inhalation, ingestion, dermal and injection [11, 12, 13]. Factors that can alter the risk levels in nanoparticles include:
- The quantum of material (mass / number of particles)
- Condition of materials (solution / powder)
- Degree of exposure
- Dosage levels
The particles of similar dimensions and elemental compositions can have different properties if the chemical architecture of such particles are modified e.g. diamond crystal and bucky balls. Nanoparticles in the aggregates are likely exhibit the biological effects that could be different from the bigger particles obtained from the same substrate.
Nanomaterials, like single walled carbon nanotubes, vary in terms of the physical forms and physical properties, which make difficult to apply generic rules about the potential health effects. A list of potential hazards due to nanomaterials has been published regardless of their quantitative effects . In many cases, analogies have been drawn with results from very small particles present in large numbers in the urban air, and in some workplaces.
Also, there is no established literature available regarding removal of nanomaterials from human body, water or soil. Inhalation of the nano spheres and nanotubes could cause serious troubles, especially for workers, who are involved in manufacturing and handling.