41
membranes: inner and outer membrane. Being damaged by any incident, membrane
degrades or destroys essential functions of the cell. Foley et al. have shown that
fullerenes can cross the membrane of living cells and localize in the mitochondria
(Foley et al. 2002). The size-dependent permeability of nanoparticles has been
reported by Salnikov et al. (2007). They claimed that 3 nm gold particles could pass
membranes of mitochondria while 6 nm gold nanoparticles could not. It has been
shown that airborne particles were found in the organelle (Li et al. 2003). Another
research has revealed that ambient ultrafine particles caused damage to mitochondria with increased calcium uptake and ROS production (Xia et al. 2006). A research
carried out by Hussain et al. on metallic nanoparticles has confirmed that among
them, silver nanoparticles are the most likely to lead to dysfunction of mitochondria
(Hussain et al. 2005).
Nucleus includes DNA and damage to DNA leads to genetic mutations. Diseases
resulted from these mutations can be transmitted to next generations. Thus, it is of
great importance to investigate the effects of nanoparticles on DNA. Godbey has
claimed that possible portals of entry of nanoparticles into nucleus membrane can
be either via interaction of nanoparticles coated with phospholipids with the membrane or diffusing through pores (Godbey et al. 1999). Nanoparticle may also lead
to protein misfolding and bring about dysfunction of it. When taking internally produced nanoparticles and their interaction with engineered nanoparticles into
account, the scenario of their circulation and fate becomes fiendishly complicated.
Most kinds of diseases are associated with protein misfolding. The protein misfolding may cause non-functioning proteins, change their solubility or production
of toxic oligomers (Cottingham et al. 2002). If the misfolding increases, highly
probable are adverse consequences. It has been shown that nanoparticles have the
ability to affect protein folding. Nanoparticles can disturb protein folding and the
phenomenon is known as chaperone effect. Billsten et al. reported that silica particles of 9 nm can change the configuration of human carbonic anhydrase II (Billsten
et al. 1997). It has been revealed that the rate of fibrillation of amyloid has been
perturbed by nanoparticles (Linse et al. 2007). However, Ishii et al. showed that
semiconductor nanoparticle can be stabilized and they can be transported by
Adenosine triphosphate (Ishii et al. 2003). This is promising for future biomediated
devices. It is clear that the available data are lacking to reveal the interaction of
nanoparticles with proteins and their effect is too far to be predicted for now.
The particle size is of key importance for evaluating health hazards of airborne
particles. Relatively larger particles (>10 μm) are generally caught in the nose and
throat. Particles which are smaller than 10 μm get access to upper branches where
body removes them by coughing, spitting, or swallowing (Jang 2012). As particle
size decreases, they can travel further. Particles with size of 5 μm and smaller can
reach bronchial tubes at the top of the lung. Particles which are smaller than 2.5 μm
get access to alveolar portions of lungs. Although their toxicological mechanism is
not clear enough to draw some logical conclusions, there are strong association
between fine particles and health hazards such as lung cancer, cardiovascular diseases, asthma, and bronchitis. Particles smaller than 0.1 μm (in the range of
nanoscale, 1–100 nm) have been shown to be most harmful since they can reach
2 Nanomaterials and Human Health
membranes: inner and outer membrane. Being damaged by any incident, membrane
degrades or destroys essential functions of the cell. Foley et al. have shown that
fullerenes can cross the membrane of living cells and localize in the mitochondria
(Foley et al. 2002). The size-dependent permeability of nanoparticles has been
reported by Salnikov et al. (2007). They claimed that 3 nm gold particles could pass
membranes of mitochondria while 6 nm gold nanoparticles could not. It has been
shown that airborne particles were found in the organelle (Li et al. 2003). Another
research has revealed that ambient ultrafine particles caused damage to mitochondria with increased calcium uptake and ROS production (Xia et al. 2006). A research
carried out by Hussain et al. on metallic nanoparticles has confirmed that among
them, silver nanoparticles are the most likely to lead to dysfunction of mitochondria
(Hussain et al. 2005).
Nucleus includes DNA and damage to DNA leads to genetic mutations. Diseases
resulted from these mutations can be transmitted to next generations. Thus, it is of
great importance to investigate the effects of nanoparticles on DNA. Godbey has
claimed that possible portals of entry of nanoparticles into nucleus membrane can
be either via interaction of nanoparticles coated with phospholipids with the membrane or diffusing through pores (Godbey et al. 1999). Nanoparticle may also lead
to protein misfolding and bring about dysfunction of it. When taking internally produced nanoparticles and their interaction with engineered nanoparticles into
account, the scenario of their circulation and fate becomes fiendishly complicated.
Most kinds of diseases are associated with protein misfolding. The protein misfolding may cause non-functioning proteins, change their solubility or production
of toxic oligomers (Cottingham et al. 2002). If the misfolding increases, highly
probable are adverse consequences. It has been shown that nanoparticles have the
ability to affect protein folding. Nanoparticles can disturb protein folding and the
phenomenon is known as chaperone effect. Billsten et al. reported that silica particles of 9 nm can change the configuration of human carbonic anhydrase II (Billsten
et al. 1997). It has been revealed that the rate of fibrillation of amyloid has been
perturbed by nanoparticles (Linse et al. 2007). However, Ishii et al. showed that
semiconductor nanoparticle can be stabilized and they can be transported by
Adenosine triphosphate (Ishii et al. 2003). This is promising for future biomediated
devices. It is clear that the available data are lacking to reveal the interaction of
nanoparticles with proteins and their effect is too far to be predicted for now.
The particle size is of key importance for evaluating health hazards of airborne
particles. Relatively larger particles (>10 μm) are generally caught in the nose and
throat. Particles which are smaller than 10 μm get access to upper branches where
body removes them by coughing, spitting, or swallowing (Jang 2012). As particle
size decreases, they can travel further. Particles with size of 5 μm and smaller can
reach bronchial tubes at the top of the lung. Particles which are smaller than 2.5 μm
get access to alveolar portions of lungs. Although their toxicological mechanism is
not clear enough to draw some logical conclusions, there are strong association
between fine particles and health hazards such as lung cancer, cardiovascular diseases, asthma, and bronchitis. Particles smaller than 0.1 μm (in the range of
nanoscale, 1–100 nm) have been shown to be most harmful since they can reach
2 Nanomaterials and Human Health