Aim:
Microfertilizers based on nanomaterials differ from traditional ones and require more detailed studies of their toxicological properties. The aim of the investigation was to study the toxicological properties and safety of the micronutrients in the experiment.

Objects of the research:
Microfertilizer of various brands based on bio-polymer-stabilized colloidal solutions of nanoparticles of microelements (Co, Mn, Cu, Fe, Zn, Cr, Se, Mo, Ag in various combinations and concentrations).

Methods of investigation:
Toxicological, physiological, hematological, biochemical and statistical.

Results:
A study of acute toxicity with a single intragastric administration for all brands of microfertilizer revealed a complete absence of symptoms of intoxication and death of animals in the limiting dose (15 000 mg / kg b.w.). Studies of cumulative properties (the effect of toxicity during accumulation) were performed with repeated intragastric administration of microfertilizer (within 30 days) at a dose of 1,500 mg / kg b.w. Symptoms of intoxication and death are not revealed. To verify immunotoxicity and sensitizing effect, intradermal administration of microfertilizer doses above 5,000 mg / kg b.w. was performed. The test showed complete absence of edematous proliferative reaction. When tested on seeds of radish, cucumber and oats, the complete absence of phytotoxicity of microfertilizer is shown. On the contrary, the effect of stimulation of the process of germination of test seeds and an increase in the length of rootlets of seedlings was revealed. In the study of reproductive toxicity microfertilizer was daily administered per os to a group of pregnant female rats. There were no clinical signs of poisoning of the mother organism. Miscarriages and premature births were not noted. When examining the effect on the reproductive function of males and females, microfertilizer was intragastric administered to a group of males and females 7 weeks before mating. Then the females were introduced during pregnancy and feeding. It has been established that microfertilizer does not affect the reproductive function of males and females.

Conclusion:
It is established that microfertilizer of all brands is low-toxic, is not eco- and phyto- toxic, is not cause long-term consequences when used (no mutagenicity, genotoxicity, effects on reproductive function).