Environmental Risks of Nanomaterials - Nanotechnologies for Water Environment Applications - page 610

clear at all. Currently, studies on the antimicrobial properties of NMs and their
interactions with microorganisms are limited to tests in pure cultures. It is not clear how
microbial communities respond to NMs as a function of NM chemical and physical
properties (such as composition and stability) and the environment in which the microbial
community exists. Moreover, frameworks allowing the extrapolation of in vitro results to
natural systems or to assess the risks of forthcoming NMs based on previous knowledge
are needed (Navarro et al., 2008).
Engineered NMs are already being produced, used and disposed. Humans are
already exposed to a range of natural and man-made NMs. Exposure to NMs via the
food, water, as well as medical applications will likely impact the public health and the
environment. However, accurate risk evaluation of the NMs to human remains difficult
due to the lack of toxic data and our poor understanding of human exposure routes.
Although some scientific information on the impact of NMs is being made, the public
generally do not yet understand the implications of the nanotechnology enhanced
products (Lee et al., 2005).
The public knowledge of pollution and health is not focused on NMs yet. People
view air quality in the context of more obvious features such as traffic density, the
quality of vegetation and dust in the air ( Bickerstaff, 2004 ). However, toxicology studies
on animals and cells raise the possibility of NMs to cause adverse effects on the immune
system, oxidative stress related disorders, and diseases such as cancer (tumor formation).
Toxicologists have a perception and expectation of the risks of NMs that is different
from the general public, and thus 'uncertainty factors' of NMs are being considered in
risk evaluation. Scientists and regulators have already recognized the importance of
modifying test methods and risk assessments, and establishing new legislation for the
safe use of NMs.
17.6 References
Adams, L.K., Lyon, D.Y., Alvarez, P.J.J. (2006). "Comparative ecotoxicity of nanoscale
TiO 2 , SiO 2 , and ZnO water suspensions." Water Research, 40, 3527-3532.
Aitken, R.J., Creely, K.S., and Tran, C.L. (2004). Nanoparticles: An Occupational
Hygiene Review . Research Report 274. Prepared by the Institute of Occupational
Medicine for the Health and Safety Executive, North Riccarton, Edinburgh,
England.
Allen, J.I., and McVeigh, A. (2004). “Towards computational models of cells for
environmental toxicology.” J. Mol. Histol., 35, 697-706.
Babynin, E.V., Nuretdinov, I.A., Gubskaya, V.P., Barabanshchikov, B.I. (2002). “Study
of mutagenic activity of fullerene and some of its derivatives using His+