In 2007, researchers from Arizona State University, USA, conducted a survey among ordinary Americans on the one hand and 363 scientists and engineers involved in nanotechnologies on the other. They were asked to name the perceived benefits and risks of nanotechnologies. Among the risks, ordinary Americans placed increase of interference in private life on top of the list, then – increase of unemployment, arms race and danger of use of nanotech by terrorists. Risk for health was only fifth on the list. At the same time, nanotech specialists put health risks on the first place. This picture reflects the fact that the media primarily draw attention to what types of new services, goods and arms will appear and how it will affect the geopolitics and world economy, often letting out of sight such boring issues as common safety. It is enough to take a look at how the reviews and video materials dedicated to nanotechnologies usually begin with. For example, it is told that nanoparticles are objects with the size of 1 to 100 nanometers and a nanometer (nm) is one billionth part of a meter, which is one millionth part of a millimeter and to be clear add that thickness of a human hair is 80,000 nm, although it would be much more understandable to use another comparison – with the thickness of tubes of asbestos fiber, the external diameter of which is 26 nm and internal – 13 nm. Asbestos is a typical nanomaterial, though it has been known since the times of Ancient Rome.

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According to the information published by the World Health Organization in July 2010, around 125 mn people are subject to effect of asbestos at their working places in the whole world and around 107,000 people die annually from diseases caused by asbestos. The EU issued a directive in 1999 prohibiting the use of all types of asbestos on its territory starting from January 5, 2005. Asbestos dust consists of fragments of nanofiber, which thanks to their small size can be inhaled into the respiratory tract to bronchial tubes and alveoli, even having the length of up to 100,000 nm. Carbon nanotubes are one of the most popular modern nanomaterials and by their size are very similar to asbestos dust.

Ball-shaped nanocrystals have become just as popular. For example, such nanoparticles from titanium dioxide and zinc oxide are widely used as bleaching and antiseptic substances in many consumer goods, including textile items, cosmetics, sun-protection creams, food products, in particular crab sticks. The sizes of these particles can be characterized by the following comparison: they are several times smaller than 70 nm and 70 nm is the minimum size of objects that macrophages (translated from Greek as large predators) are capable of seeing. The macrophages are actively motile body cells capable of ingesting bacteria, remains of dead cells and other foreign or toxic for the body particles.

The results of the studies conducted by Plymouth University, UK and published in September 2011 showed what accumulation of nanoparticles in an organism could lead to. The tests run on rainbow trout showed that titanium dioxide nanoparticles provoke formation of holes in nervous cells of some parts of the brain, which causes death of these cells. By their effect, nanoparticles turned out to be similar to mercury, which also has the capacity to accumulate in an organism.