Agriculture Reference
In-Depth Information
medium. A higher uptake was achieved in hydroponic medium as compared to the
plant grown in sand, whereas no uptake was observed in plants grown in soil which
might be due to the adherence of magnetite nanoparticles to soil and sand grains. In
contrast, no uptake was found in treated lima bean plants, showing that uptake of
nanoparticles is also dependent on plant species. Wang et al. (
2011
) reported no
uptake of magnetite nanoparticles in pumpkin plants because of the large size of
nanoparticles. Effect of functionalization on uptake of nanoparticles was studied by
Corredor et al. (
2009
) by applying carbon-coated iron nanoparticles on leaf of
pumpkin plant. They observed presence of nanoparticles in epidermal cells but
could not find nanoparticles near xylem. Lee et al. (
2008
) studied the uptake and
translocation of copper nanoparticles in mung bean and wheat in agar growth
medium. They reported that copper nanoparticles can cross the cell membrane
and agglomerate in the cell. Unlike the conclusive studies on TiO
2
and ZnO
nanoparticles, most of the uptake, translocation, and accumulation studies in plants
are reported only up to the germination stage. Thus, the fate of nanoparticles in the
plant system is largely unknown (Rico et al.
2011
). The details of storage in plant
system are yet to be elucidated.
4.8 Ethical and Safety Issues in Using Nano-fertilizers
Although nanotechnology has incredible potential to revolutionize many aspects of
human life, the benefits may come with some price. One of the major questions
faced by the world before accepting nanotechnology is whether the unknown risks
of nanoparticles involving their environmental and health impact prevail over their
potential benefits. The risks associated with the application of nanoparticles are yet
to be evaluated before fully implementing this technology. This consideration has
developed “nanotoxicology,” which is responsible for assessing toxicological
potential as well as promoting safe design and use of nanoparticles (Oberd¨rster
et al.
2005
). A systematic and thorough quantitative analysis regarding the potential
health impacts, environmental clearance, and safe disposal of nanoparticles can
lead to improvements in designing further applications of nanotechnology (Meng
et al.
2009
).
Although no direct human disease has been linked to nanoparticles so far, early
experimental studies indicate that nanoparticles could initiate adverse biological
responses that can lead to toxicological outcomes (Nel et al.
2006
). Nanoparticles
which constitute a part of ultrafine particulate matter can enter in the human/animal
system through oral, respiratory, or intradermal routes. Currently, there is a com-
mon assumption that the small size of nanoparticles allows them to easily enter
tissues, cells, and organelles and interact with functional biomolecular structures
(i.e., DNA, ribosomes) since the actual physical size of an engineered nanostructure
is similar to many biological molecules (e.g., antibodies, proteins) and structures
(e.g., viruses). A corollary is that the entry of the nanoparticles into vital biological
