Risk Assessment on Silver Nanoparticles - Research Paper Example

Risk Assessment on Silver Nano-Particles Introduction Nanotechnology involves use of modern skills in the production of components from simple particles and is based on the ability to influence the formation of a complex structure from a simple state. (Wijnhoven.et.al.110). As result of its wide application, most of the products have traces of nano-particles though at a varying degree. However, as more products are currently manufactured using nanotechnology, this has raised concern over the negative impact it may have on both human beings and on the surroundings (Wijnhoven.et.al, 128). It is believed that prolonged exposure to these substances may result to complications on both human health and to the environment. The perceived consequences of this technology may limit its application in order to reduce its impact on human lives (Peters, 2012). This study examines the extent to which nano-particles may affect human lives and their surroundings and means through which these effects can be prevented. Finally this study will assess the paths through which nano-particles may find their way into human beings and the environment. Background and Application of Nanotechnology Uses of the Nano-Materials Nanotechnology is widely used in the manufacture of different components due to the varying characteristics of its atoms which eventually determine the quality of the entire component (Wijnhoven.et.al. 116). Depending on their sizes, nano-particles significantly influence the nature of the component such as color, texture, magnetism, conductivity and flexibility. The characteristics of metal components will vary according to the size of nano-particles present in that particular component. This technology has been used in the manufacture of smartfridge which utilizes nano-silver particles to preserve food. The same technology has been used in sterilizing various equipments such as children toys, cleaning of wounds, manufacture of cloth and keyboard (Wijnhoven.et.al, 117). In smartfridge, nano-silver sterilizes food particles by destroying all bacteria presents in food (Wijnhoven.et.al, 127). Due to low temperature present in the fridge and absence of bacteria, the food can be stored for a longer period before going into waste. Silver ions react with enzymes present in bodies of the bacteria hence choking them due to lack of oxygen and eventually denatures the bacteria. The size of the particles will influence the performance of the components. For example, very tiny particles of less than 10nm will easily penetrate in the body of bacteria which is quite larger compared to bacteria (Wijnhoven.et.al. 123). Also, the size of nano-particles used in manufacturing components will determine their ability to float or sink in fluid. Therefore, smaller nanosilver particles will easily circulate in the smartfridge hence reaching all bacteria present in food (Peters, 2012), Nano-particles will likely result into superior perfection in testing and treatment of human diseases such as tumor, improve efficiency in drugs administration (Benn, and Westerhoff, 7025). Boundaries of the Risk Assessment Nanoparticles are used in manufacture of various commodities which are used by all human beings on a day to day life (Hussain, and Schlager, 223). For example they are used in manufacturing and preservation of food, consumer commodities, in medicine, and are also present in the surroundings from various sources (Tolaymat, 1005). In smartfridge, the presence of nanosilver results to exposure of many people or all ages and background because many people have higher chances of tasting the food. Those who work in food industries or use fridges at home are also exposed to nano-silver particles which they may inhale, consume with food or assimilate through the skin (Wijnhoven.et.al, 119). If waste water from smartfridges is dumped into water treatment system, nanoparticles will destroy bacterial responsible for decomposition of the organic matter in the treatment system. These will breakdown the treatment process (Wijnhoven.et.al, 128). In addition, if water from smartfridges comes into contact with soil, high levels of silver particles may cause interference with the soil bacteria which are responsible for decomposing organic matter in the soil (Benn & Westerhoff ,7026). Hazard and Exposure Identification Due to wide application of silver in processing of various components, there is probability of high level of nano-particles in the surroundings people can come into contact with them through various means including inhalation, oral uptake and assimilation through the skin (Wijnhoven.et.al, 116). These are likely to be swallowed with food from the smartfridges, or inhaled directly thus causing health hazard to human beings. Dose response and toxicity evaluation The level of nano-particles such as silver ions will not be poisonous to human health or to the environment unless they have accumulated up to a certain level. Between less than 6 to 1000ppm such as of silver is not considered dangerous (Tolaymat, 1002). Most of nano-silver particles are taken with food and water into the body and remains the major means into which these particles get into the body accounting for 70-90µg.day-1. After nano-particles have got into the human body, some of it assimilated into the blood through gastrointestinal wall (Wijnhoven.et.al, 114). These particles are spread into the entire body through blood. Others are assimilated through the skin or wound during cleaning. In (Hussain and Schlager 224), during breathing in of the air, some particles due to their light weights are taken into the lungs through olfactory system. About 15nm of the inhaled nano-particles are deposited in the olfactory system while the rest is proceeds to the lungs. However, these particles may not reach dangerous level because some of the ingested particles are also eliminated through excreta or thorough urine (Wijnhoven.et.al, 133). This reduces danger of such particles accumulating in the body to a level which is poisonous to the body. Exposure Assessment All people are generally susceptible to exposure to nano-particles because these particles are present everywhere. However, the exposure time and level of particles will differ (Hussain and Schlager, 224). For example, those people who work in chemical processing companies have higher rate of exposure due to large dust particles present in the atmosphere. This mainly occurs through inhalation of the dust. Longer exposure time will result to significant risk due to accumulation of these particles to a high level (Wijnhoven.et.al. 131). Risk Characterization One of the likely consequences is assimilation of produced nano-particles into the human bodies (Tolaymat, 1006). Due to large surface area compared to volume of these nano-particles, they can easily penetrate into the body of human beings either via skin pores, or through lungs when they are inhaled and through alimentary canal if ingested into the body. These particles may cause damages to different body organs (Hussain and Schlager, 224). Most nano-particles such as iron oxide, Titanium dioxide, Zinc oxide and copper oxide have potential for damaging DNA. The presence of nano-particles in the surroundings may affect process decomposition of organic matter hence resulting to deficiency of nutrients to crops (Tolaymat, 1003). The accumulation of these particles on plants will also affect photosynthesis and hence poor plant growth. Risk management strategy To minimize the effect of overexposure of human beings to the nano-particles, people should shorten the period in which they store food in the fridges. Longer period of storage will result to accumulation of nanosilver particles to a level which is dangerous to human beings (Tolaymat, 1005). Also, those people who deal with smartfridges should minimize the time of exposure to the fridges. This will also reduce the chances of inhaling or coming into contact with nanosilver particles to a level which may affect their health (Wijnhoven.et.al. 130). It is important for people to use protective materials while using smartfridges so as to reduce risk of exposure to nanosilver particles. In (Tolaymat, 1004), manufacturers of smartfridges should ensure the level of nano-particles released by those components is kept as low as possible to avoid causing damages to the environment and to the human lives. Evaluation and selection alternatives for mitigation The presence of nickel in silver may cause sensitivity effects on human beings. Silver nano-particles may also result into discoloration of some body organs such as liver and brain, a condition referred to as Argyria (Wijnhoven.et.al. 134). However, the discoloration effects do not last long since it comes to an end with time. Nano-particles may affect waste treatment due to discharge of nanosilver particles which interfere with the bacteria responsible for decomposing waste in the treatment system (Wijnhoven, et.al. 125). Therefore, the water which has been used for cleaning smartfridges should be disposed in a proper channel where it will have minimal effects in the environment (Benn, 7025). Conclusion and recommendation The increase use of nanotechnology has improved production of various items due to increased efficiency and wide of application of components (Tolaymat, 1002). However, there is a perceived risk of human health and surroundings due to prolonged exposure and intensity of nano-particles in the atmosphere. It is essential for further investigation to be carried out to establish the amount of nano-particles which may cause damage to human health as well as to the environment. Works Cited Benn, T.M. and Westerhoff, P. Nanoparticle. Silver Released Into Water from Commercially Available Sock Fabrics. Environ Sci. Technol 42:4133-4139. Erratum in: Environ Sci Technol 42: 2008. 7025-7026. Hussain, Saber M. and Schlager, John J. Safety Evaluation of Silver Nanoparticles: Inhalation Model for Chronic Exposure: Oxford Journals Life Sciences & Medicine Toxicological Sciences Volume, 108(2).2009. 223-224. Peters, Sheona, e.d. Feasibility and Challenges of Human Health Risk Assessment for Nanomaterials. SafeNano, 2012. Tolaymat, T.M., El Badawy, A.M., Genaidy, A., Scheckel, K.G., Luxton, T.P., and Suidan, M. An Evidence-Based Environmental Perspective of Manufactured Silver Nanoparticle in Syntheses and Applications: A Systematic Review and Critical Appraisal of Peer- Reviewed Scientific Papers. Sci Total Environ.; 408 (5): Elsevier B.V. 2010, 999-1006 Wijnhoven, Susan, W.P. et.al. Nano-Silver a Review of Available Data and Knowledge Gaps in Human and Environmental Risk Assessment. Nanotoxicology. Informa Healthcare, 2009. 3(2). 109-138 Read More