The safety of nanotechnology is guaranteed. Paper will endure everything…
Macro tasks for microparticles
Rossiyskaya Gazeta, 12.10.2011
The Federal Target Program "Development of Nanoindustry Infrastructure in the Russian Federation for 2008-2011" is coming to an end in November.
One of its directions was the creation of a safety assessment system for nanomaterials and nanotechnologies. It has been successfully completed: regulatory and methodological documents have been developed in Russia for all stages of safety assessment and control, experimental methods for testing nanoproducts on various models have been developed, laboratories responsible for their examination and control have been accredited.
– The problem of nanoparticles is not new in scientific terms, the theoretical basis explaining the properties of dispersed systems has existed since the nineteenth century, – says Ivan Gmoshinsky, a leading researcher at the Institute of Nutrition of the Russian Academy of Medical Sciences, Doctor of Biological Sciences. – Everything that exists around us – any aerosols, dust, fogs, soot particles in case of fire – these are highly dispersed, that is, nanoscale systems. Naturally, the question arose whether human contact with them is dangerous. To answer it, it was necessary to create a safety assessment and control system for nanotechnology and nanomaterials.
This task was set before scientists when, in reality, neither one nor the other did not exist. Such caution was caused by the fact that humanity already has a bitter experience of unsuccessful implementation of the latest technologies that society has not accepted.
– Any mistake or delay in this area is fraught with serious consequences, – says the director of the Institute of Nutrition of the Russian Academy of Medical Sciences, Academician Viktor Tutelyan. – And the more innovative the technology is, the more carefully we need to prepare for its implementation, and especially in what concerns humans directly – in the production of food, medicines, new materials.
An example is the formation of a negative attitude towards genetically modified organisms (GMOs). These technologies can dramatically increase the yield of valuable crops, improve the structure of nutrition. But large firms, having invested a lot of money in technology, did not take care of preparing public opinion for its perception. As a result, GMOs are rejected in many countries, although there is no scientific data on the harm of GMOs to humans.
On the other hand, there are negative examples of underestimating the danger of new materials. For example, polychlorinated biphenyls have been widely used in electrical engineering for many years, and they were released into the external environment in huge quantities. As a result, they accumulated in living organisms and are now one of the global pollutants of the environment
These negative examples were taken into account as soon as nanotechnology began to develop. The scientists were tasked with creating an effective and rigorous system for assessing the risks of possible negative impact on people of new products and technologies and their control.
The question arises: if nanoforms of substances have always existed in nature, what is the danger of new nanomaterials? The fact is that artificial nanoparticles have a complex of physical, chemical properties and biological effects that are radically different from the properties of the same substances in the form of continuous media or larger dispersions. Firstly, they have greater solubility and the ability to react. Secondly, a very large surface area of nanomaterial particles increases their ability to bind heavy metal ions, pesticides and radionuclides compared to larger particles. They thereby act as a kind of "Trojan horse". Their ability to produce free radicals, which damage the body's cells and even DNA, is also increased. In addition, due to the small size of nanoparticles, they may not be recognized by the body's immune system and are not excreted from it, which can lead to their accumulation. Many of these effects have been confirmed experimentally and are considered scientifically proven.
These risks are not something speculative. In 2006, a landmark incident occurred in Germany – the first ever case of mass intoxication with silicate nanoparticles, which were part of a spray for cleaning baths and sinks. About 70 people were poisoned, and six of them were hospitalized with pulmonary edema. As a result, the entire batch of funds was withdrawn from the market. But the lesson of this story is different – all new products manufactured using nanotechnology should be carefully checked for safety. Especially when it comes to food or cosmetics.
One of the important directions is the use of nanotechnology in food production. For example, the use of nanoscale forms of trace elements. The expediency of this is determined by the fact that there is a problem of a small interval between the necessary and toxic levels of their consumption. New forms allow it to be solved for a number of minerals that are indispensable in nutrition – iron, selenium, zinc, etc. Nanoincapsulation makes it possible to overcome the incompatibility of various nutrients, for example, copper and vitamin C. It also increases the bioavailability of many substances, protecting them from the effects of gastric juice. Nanoparticles can also be used as preservatives, fillers, dyes, flavors and other food additives. And the use of nanotechnology for the manufacture of food packaging materials allows you to increase the shelf life of products, preventing their contamination by microbes by reducing the size of pores or increasing the absorption of UV rays.
The process of mastering these technologies by the food industry is still at the very beginning. Today, about 30 nanoproducts of the food industry are present in the register maintained by the Institute of Nutrition of the Russian Academy of Medical Sciences. These are actually food products, biologically active food additives, and packaging materials for it. However, the forecast of the development of this direction, which was compiled by the institute's specialists on the basis of determining the number of patent developments in this area awaiting their practical implementation, shows that since 2013 we are waiting for an avalanche–like growth of food nanoproducts - the bill will go to at least hundreds.
Scientists of the Research Institute of Nutrition of the Russian Academy of Medical Sciences have developed methodological recommendations for identifying nanomaterials that pose a potential danger to human health. They are based on the method of mathematical modeling and allow you to calculate and classify the degree of danger as low, medium and high. Depending on this, the volume of toxic and hygienic studies of a particular nanomaterial is determined. Priority materials for the domestic nanoindustry have already passed this examination in full.
Experiments on various models – cells, plants, laboratory animals – were carried out with nanoparticles of titanium dioxide, silicon dioxide (silica, silica gel) and nanoscale silver. The first compound is used in the cosmetic industry, the second – in various abrasive materials, as well as as a food additive, and colloidal silver – as a disinfectant.
Thus, the introduction of titanium dioxide nanoparticles to rats demonstrated their toxic effect – the animals grew worse, they had changes in the indicators of antitoxic protection of the liver, glucose, hemoglobin and platelet count. Experiments with silica nanoparticles, on the contrary, have shown their harmlessness even in high doses.
The third product that went through a full cycle of experimental research was nanoscale silver. In the experiments, the doses of nanoparticles that are completely harmless and those at which small shifts in individual biochemical processes may occur were determined.
Based on a comprehensive study of priority nanomaterials, scientists have also developed hygienic standards for their presence in environmental objects – the air of the working area, the water of reservoirs and drinking water. They are approved and binding on all subjects of law in Russia. Work continues on other practically important nanomaterials and nanoparticles.
So, the country has developed one of the strictest and most effective systems for safety assessment and control of nanotechnology and nanomaterials in all aspects. The task set before the scientists was twofold. On the one hand, it was impossible to slow down the progress in these works, not to get bogged down in endless research and experiments. On the other hand, clear guarantees of complete security for the population were required.
To begin with, a calculated assessment of the potential danger of nanomaterials, that is, material objects having near-molecular sizes ranging from 1 to 100 nanometers, was chosen.
– More than 2000 papers on the toxicological and hygienic characteristics of nanomaterials and their testing on a variety of models - bacteria, cells, crustaceans, fish, mammals, etc. have already been published in the world, – continues Ivan Gmoshinsky. – It was necessary to collect all the data, analyze them using mathematical methods, develop algorithms for calculating several levels of potential danger – small, medium, high. And determine the ways to further study them.
Based on this analysis, a structured document system was created. There are six levels in it – priority determination based on mathematical modeling; algorithms for quantitative analysis and rationing; sampling procedures and methods; methods of toxicological, hygienic and biomedical assessment; methods of control and supervision; risk assessment and management. Among the latter are a wide range of measures – from the improvement of treatment facilities up to the change of technology and even the conversion of production if its products are recognized as dangerous.
As a result, as part of the implementation of the Federal Target Program "Development of Nanoindustry Infrastructure in the Russian Federation for 2008-2011", a complex of 28 regulatory and methodological materials establishing a two-stage system for testing the safety of nanomaterials was developed and approved by the resolutions of the Chief State Sanitary Doctor of the Russian Federation. The first stage is informational and analytical, which, based on the data of scientific literature, allows us to classify the degree of their potential danger. The country has also established a network of laboratories accredited for testing the safety of nanotechnology products, both in Moscow and in major scientific centers of the country – in Tyumen, Perm, Yekaterinburg, Novosibirsk. In a scientific sense, the problem of assessing the risks of using nanotechnology and the resulting products, as well as managing them, has been solved. The question is how it will work in practice. According to the Rospotrebnadzor decree of 2007, all manufacturers of nanoproducts are required to undergo state registration and label their products accordingly. However, there are many products on the market that are advertised as nanoproducts, but at the same time manufacturers do not indicate information about state registration. Apparently, in addition to departmental documents, a direct federal law is needed that would introduce serious liability for violating these rules and regulations.
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