35
involved nanoparticle due to coating, packaging, and filtering. Besides, as the use of
nanomaterials increases, the possibility of unintentional ingestion of nanoparticles
via food animals, fish, and water also increases (Bergin and Witzmann 2013).
Swallowing of mucus secreted by respiratory system can also lead to particle digestion because the mucus is likely to be impacted by nanoparticles. Lomer et al. have
estimated that about a thousand particles up to three microns are ingested each day
by a person in developed countries (Lomer et al. 2002). These particles generally
include titanium dioxide, food colorants and silica. Now let us look at the findings
related to exposure of nanoparticles by the digestive system. The absorption of
nanoparticles in the gastro-intestinal tract depends on their charge, size, surface
chemistry, length, and dose (Hoet et al. 2004). Kreyling et al. have reported that
nanoparticles of 18 nm were absorbed in the gut wall in rats (Kreyling et al. 2011).
Florence showed that positive charge of particles facilitates their uptake in the gut
(Florence 2005). Jani et al. carried out a research to figure out the size effect of
nanoparticles on uptake (Jani et al. 1990). They showed that the smaller the particles
are, the higher the uptake is. Also it was reported that the gastrointestinal barrier is
not effective for smaller particles (Ballestri et al. 2001). Chen et al. worked on nanocopper and the acute toxicity of bulk copper particles in mice (Chen et al. 2006).
They found that nanocopper was more dangerous and lethal than bulk copper particles and they also reported that nanocoppers led to damage to spleen, liver, and
kidney. Also the health condition of people has great impact on nanoparticle accumulation. People who have Crohn’s disease, cancer, and ulcerative colitis have
nanoparticles constantly in their colon tissue, while healthy people do not (Gatti
2004). Lately, it was believed that one of the reasons of Crohn’s disease is the intake
of high-level dietary nanoparticles (100 nm–1 μm) and the treatment of this disease
generally requires surgical intervention (Lomer et al. 2002).
Nanoparticles can enter the body via inhalation, gastrointestinal assimilation and
dermal absorption. Nanoparticles also can be transported to central nervous system
through blood–brain barrier or olfactory mucosa. This is very important in terms of
drug delivery for damaged parts. Depending on their properties such as size, solubility, surface charge etc., they can be highly mobile in the body. Thus, their translocation tends to be remarkably fast. However, it has not been fully clarified of the
relationship between the properties of nanoparticles and their circulation and fate in
the body. Most of the conclusions have been drawn from animal models and it has
remained as big challenge whether these models can be applied to human.
Although the effects of bioaccumulation of airborne particles on health have
been established, the effects of ultrafine and nanoparticles on health have not been
elucidated. Evidences indicate the translocation of iridium nanoparticles from lung
to liver, spleen, heart, brain (Stern and McNeil 2008). They reported that smaller
particles have a higher translocation rate.
It is particularly significant to determine the distribution of nanoparticles in the
body. Once nanoparticles enter the body somehow and gain access to the blood
circulation, they can be transported through body. Because of the small size, nanomaterials can run through the lungs into the bloodstream and they can reach potentially susceptible sites such as kidney, heart, spleen, and liver (Sturm 2015).
2 Nanomaterials and Human Health
involved nanoparticle due to coating, packaging, and filtering. Besides, as the use of
nanomaterials increases, the possibility of unintentional ingestion of nanoparticles
via food animals, fish, and water also increases (Bergin and Witzmann 2013).
Swallowing of mucus secreted by respiratory system can also lead to particle digestion because the mucus is likely to be impacted by nanoparticles. Lomer et al. have
estimated that about a thousand particles up to three microns are ingested each day
by a person in developed countries (Lomer et al. 2002). These particles generally
include titanium dioxide, food colorants and silica. Now let us look at the findings
related to exposure of nanoparticles by the digestive system. The absorption of
nanoparticles in the gastro-intestinal tract depends on their charge, size, surface
chemistry, length, and dose (Hoet et al. 2004). Kreyling et al. have reported that
nanoparticles of 18 nm were absorbed in the gut wall in rats (Kreyling et al. 2011).
Florence showed that positive charge of particles facilitates their uptake in the gut
(Florence 2005). Jani et al. carried out a research to figure out the size effect of
nanoparticles on uptake (Jani et al. 1990). They showed that the smaller the particles
are, the higher the uptake is. Also it was reported that the gastrointestinal barrier is
not effective for smaller particles (Ballestri et al. 2001). Chen et al. worked on nanocopper and the acute toxicity of bulk copper particles in mice (Chen et al. 2006).
They found that nanocopper was more dangerous and lethal than bulk copper particles and they also reported that nanocoppers led to damage to spleen, liver, and
kidney. Also the health condition of people has great impact on nanoparticle accumulation. People who have Crohn’s disease, cancer, and ulcerative colitis have
nanoparticles constantly in their colon tissue, while healthy people do not (Gatti
2004). Lately, it was believed that one of the reasons of Crohn’s disease is the intake
of high-level dietary nanoparticles (100 nm–1 μm) and the treatment of this disease
generally requires surgical intervention (Lomer et al. 2002).
Nanoparticles can enter the body via inhalation, gastrointestinal assimilation and
dermal absorption. Nanoparticles also can be transported to central nervous system
through blood–brain barrier or olfactory mucosa. This is very important in terms of
drug delivery for damaged parts. Depending on their properties such as size, solubility, surface charge etc., they can be highly mobile in the body. Thus, their translocation tends to be remarkably fast. However, it has not been fully clarified of the
relationship between the properties of nanoparticles and their circulation and fate in
the body. Most of the conclusions have been drawn from animal models and it has
remained as big challenge whether these models can be applied to human.
Although the effects of bioaccumulation of airborne particles on health have
been established, the effects of ultrafine and nanoparticles on health have not been
elucidated. Evidences indicate the translocation of iridium nanoparticles from lung
to liver, spleen, heart, brain (Stern and McNeil 2008). They reported that smaller
particles have a higher translocation rate.
It is particularly significant to determine the distribution of nanoparticles in the
body. Once nanoparticles enter the body somehow and gain access to the blood
circulation, they can be transported through body. Because of the small size, nanomaterials can run through the lungs into the bloodstream and they can reach potentially susceptible sites such as kidney, heart, spleen, and liver (Sturm 2015).
2 Nanomaterials and Human Health