Page 457 - Environmental Nanotechnology Applications and Impacts of Nanomaterials

434 Potential Impacts of Nanomaterials

have shown to have the highest mobility and can migrate 10 meters in
unfractured sand aquifers (Lecoanet et al., 2004). Studies have also shown
that fullerol toxicity can increase in the presence of light (Pickering and
Wiesner, 2005). These studies underline the importance of basic nano-
materials chemistry to predict potential adverse effects.

Conclusion
Many of the studies discussed in this chapter clearly indicate that nano-
materials interact with biological systems. Composition, size, and sur-
face property are important attributes that are needed to predict
biological effects. It is intriguing to realize that although materials of
vastly different chemical compositions have similar interactions with
biological systems—the clearest example being preferential cellular
uptake of anionic iron oxide nanoparticles and QD. Size also seems to
be an important factor. The precise nature of toxicity seen is a function
of the chemistry of the particle. The physical chemical properties of
many nanoparticle surface modifications may be the factor that deter-
mines their ultimate safety. A great deal of literature exists for those
nanomaterials with commercial applications, including titanium diox-
ide particles for sunscreens and iron oxide particles or QD for imaging.
Similarly, pivotal disposition and cell targeting data are often available
for those nanomaterials intended for use in drug delivery, such as seen
with QD, fullerenes, and carbon nanotubes. There is a serious lack of
information about human health and environmental implications of
manufactured nanomaterials. This emerging field of nanotoxicology
will continue to grow as new products are produced. The need for toxi-
cology studies will increase for use in risk assessment. Knowledge of
exposure and hazard are needed for understanding risks associated
with nanomaterials. This chapter has explored the beginning threads
of nanomaterial toxicology for a variety of nanomaterials.

References
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