To the issue of ecotoxicological assessment of nanopreparations

Abstract

The rapid introduction of nanomaterials into agricultural practices not only opens up new prospects, but also bears a threat to natural ecosystems and people. Therefore, the urgent issue is to develope a system of environmental assessment nanopreparations that will allow justifying regulations of their use and determine the best environmentally safe rate of their application to crops. Taking into consideration the peculiarities of structure and size of nanoparticles of the basic components of nanoagrochemicals registration of negative changes at the cellular level is relevant, as well as of its organelles, processes occurring in it. This will enable preventively assess the risks, extrapolate the obtained results to a higher level of organization of biological systems and avoid possible negative impacts on the ecosystem level. Results of the study of cytotoxic effect on the cells of Allium cepa L. indicate that the use nanoagrochemicals in doses recommended for agricultural production have led to a decrease of mitotic activity. Mutations have been reported, caused by the impact of agrochemicals and were related to flagrant violation of the structure of chromosomes, damage of mitotic spindle and with the change of behavior of chromosomes on the spindle. According to the study the application of the preparation Avatar-1 at all concentrations caused 100% death of the female parent specimen of Ceriodphnia. Preparation Nano-Gro in the recommended dose caused the death of 78% of the female parent specimen, however, the increase of the applicable dose was accompanied with a decrease in the number of dead female parent specimen of Ceriodaphnia (44%). Preparation Nano-Gro reduced the number of viable affiliated individuals and the number of eggs the female laid again if compared to the control. However, the toxic effect of Nano-Gro was significantly lower compared to the preparation Avatar-1. The use of the latter, especially in high doses - 4RD (concentration of 1.00 mg/dm3 ), led to such phenomena as female deaths, birth of dead offspring, throwing eggs out at different stages of development, the birth of the offspring with underdeveloped armor, etc. Ecotoxicological assessment of the risk of nanoagrochemicals should not be based only on the study of dependence “doseeffect” at the level of the organism and population, it should include the studies of the toxic process, starting from the level of cell and its organelles.