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The crystal form of titanium dioxide nanoparticles influences the effect on the immune system

De kristalvorm van titaniumdioxide nanodeeltjes beinvloedt de maturatie van dendritische cellen


The use of manufactured nanoparticles is widespread and still increasing. For this reason, there is a need to know what effect they have on human health. In that respect, the RIVM investigated the risks of exposure to engineered nanoparticles, for example when using hair spray or sunscreen in spray form. This study shows that a specific crystal form of titanium dioxide nanoparticles has an effect on the immune system. They affect the maturation process of the so-called dendritic cells. These dendritic cells are an important part of the immune system. The percentage of cells maturing is a measure of the response of the immune system: the more cells mature, the more active the immune response to pathogens, and the like.

Titanium dioxide nanoparticles exist in two crystal forms: anatase and rutile. It turns out that the anatase form induces a greater percentage of dendritic cells to mature than the rutile form. In sunscreens titanium dioxide particles are used in both crystal forms. For this reason it seems likely that particles of the rutile form are preferred. More research is needed to make a final statement.

Diesel soot, particulate matter and titanium dioxide are known to cause an allergic reaction. In addition, more and more people acquire such a response and its severity is increasing. The results obtained support the influence of nanoparticles on the immune system and the need to pay attention to these effects. The results can be used for research into the effects of inhaled nanoparticles.

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