Biosafety of Nanotechnology in Agriculture: A Review
Divya R.K. and Biswajit Lenka
Agriculture is the backbone of the Indian economy with more than 70% of its population is directly or indirectly dependent on agriculture for a livelihood. After Independence, India faced the problem of food insufficiency as the then level of production wasn’t able to meet the increasing demand of food grains. This situation forced India to adapt the ‘ship to mouth’ concept i.e., importing of the food grains in order to feed her population.
However, thanks to the Green Revolution in India in the early 1960s. Consequently, the food grain production shot up from 50 mt in 1950 to 108 mt in 1970-71. The production of the same touched 265.57 million tons in 2013-14 (Mishra S.K., 2007). This was mainly due to introduction of semi dwarf varieties of wheat and rice, increased use of chemical fertilizers, irrigation, plant protection chemicals and farm machinery. This elevated India from a starving bowl to self-sufficiency in staple food i.e., rice and wheat..
The use of Nanotechnology in agriculture has immense research potential in order to employ it in widespread and commercial way to improve sustainability of the agro ecological system. However, like every new technology, the concept of usage of Nanotechnology in agriculture has been put to discussion to a great extent in terms of economic viability, long term environmental safety, social acceptability and most importantly its biosafety. The topic of biosafety is of utmost concern when it comes to agriculture because agriculture is the biggest interface between human beings and the environment. A technology is considered to be ethically acceptable if it causes no harm to either components of the interface. Here, in this review article, the biosafety issues of the use of Nanotechnology in agriculture, its consequences and future perspective of research in this field is discussed.
Nanotechnology in agriculture:
Nanotechnology is the science, engineering and technology conducted at the Nano scale i.e. 1-100 nm (Nano meter). It is considered to be the most versatile of the modern sciences as it has application in chemistry, biology, physics, material sciences, engineering and consistently finding its way into many other disciplines. The father of Nanotechnology is Richard Feynman. The application of Nanotechnology started in 1981 with the development of scanning tunneling microscope which is capable of imaging surfaces at atomic level which is based on quantum tunneling with the resolution of 0.1 nm lateral resolutions and 0.01 nm depth resolutions.
Nanotechnology is put to use primarily with the help of Carbon nanotubes, Mesoporous Silica Nanoparticles, Nano sensors, Nano emulsions, Silver Nanoparticles, etc. The Nanoparticles are produced by two methods which comprises of bottom up approach (self- assembly to Nano particles from atoms and molecules) and top down approach (milling to Nano scale particles from their macro scale counterparts) (Micheal Berger, 2010). These have applications in various aspects of agriculture like nutrient management, weed management, crop protection, water management, food processing and many more. Nanotechnology has an immense potential for sustainable agriculture. The idea of sustainability is to meet the current requirements without deteriorating the capacity of the system to cater to the needs of the future generation.
Sustainability is achieved by precisely detecting and delivering the correct quantity of nutrients and pesticides that promotes productivity while ensuring environmental safety. The need based application minimizes the wastage of the external inputs both spatially and temporally. This enables conservation of resources and minimizes the environmental pollution which results from indiscriminate use of synthetic inputs like chemical fertilizers and pesticides.
The whole concept of Nanotechnology in agriculture revolves around the higher use efficiency of applied inputs by better management and conservation of the same. This is achieved by the fact that when particles are reduced to Nano scale, show different behavior from macro scale which enables unique application due to its increased surface area of exposure and high sensitivity. This is not a reality with conventional agriculture. However, sustainability in the long run can be achieved only when the employed technology is economically viable in the short term. Hence, Nanotechnology can be considered as the path to sustainability through high precision which when applied on a large scale will be economically viable too.
There are many obstacles that hinder the adaption of Nanotechnology and its widespread application on the commercial levels. Some of them are social acceptability, ethical concerns, economic viability and biosafety. Out of this, biosafety is considered to be one of the major obstacles because, if the Nano products and the processes for creating them are not managed judiciously, there could be serious health and environmental risks.
Some of the threats include that the pesticides and fertilizers when in various Nano formulations especially when air borne, may deposit on above ground plant parts and may result in plugging of the stomata which hinders the gaseous exchange required for photosynthesis and respiration and also hinders the transpiration process or may create fine physical and toxic barrier on the stigma preventing the penetration of the pollen tube preventing the fertilization and seed formation (Micheal Berger, 2010). It may also enter the vascular system and hinder the translocation process and disrupt the source-sink link. It also poses a threat to the environment in many ways like increased fixation of soil applied herbicides increasing the persistence of the same in the field and possibly cause increased phyto toxicity to the subsequent crops.
It may also affect the animal life because when inhaled causes ill effects by entering into the bloodstream. It affects human health in many ways by entering into the respiratory system by inhaling the air borne particles and cause inflammation of the lungs. The other ill effects include protein fibrillation and may be the cause of induction of genotoxicity i.e. destructive effect on the cell’s genetic material (DNA and RNA) affecting its integrity and can cause mutations.
Due to these risks, the question of biosafety has to be addressed very carefully and needs to be critically analyzed and examined. The process of production of formulation and the Nano particles must be managed judiciously in order to avoid health and environmental risks involved.
The problem of various biosafety issues with respect to the environment, plants, animals and human beings can be minimized to a great extent by utilizing the Nano particles derived from biopolymers such as proteins and carbohydrates which have low impact on the same. Also, the process of synthesis of Nano particles may be changed to green synthesis i.e. microbial method and may be naturally encapsulated with mother protein polymers which results in increased stability which is eventually safer to the biological system.
Future research motives:
The existing biosafety issues of use of Nano technology in agriculture opens new windows for further research in the same field. The possible research motives may include developing bio polymers and starch based Nano particles which are not toxic to the living system. The stability of the particles should be improved within the living system at the same time the problem of higher persistence of the particles must be taken care of. This can be solved if they are microbial based formulations which can be degraded in a short span of time reducing the phyto toxicity of the subsequent crops. The behavior of the particles in varying conditions can be studied in green house conditions to predict their behavior in the field conditions.
Nanotechnology is one of the fastest growing branches of science. Like all other technologies, its usage in agriculture faces constructive criticism initially which when addressed in the correct manner can lead to a breakthrough. In the present scenario of agriculture, the main motive a technology should be attaining sustainability and maintaining the long term productivity of the system. With research advancing in biosafety and commercialization of use of Nano technology, this has very great potential in breaking the yield plateau and leading to the next Green revolution with adequate foresight.
Mishra S.K., 2007. Trends in Growth of Agriculture Sector of the Indian Economy. Dept. Of Economics NEHU, Shillong.
Micheal Berger, 2010. Nanotechnology in Agriculture
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