The accumulation of nitro compounds by plants depends on several factors, in particular: the doses and frequency of incorporation of organic and mineral fertilizers into the soil, the accumulation of nitro compounds in soil and plants, climatic conditions, the period of physiological development of plants, water insufficiency, etc. All of these factors contribute to the accumulation in amounts that exceed the admissible limit concentration (ALC) of nitro compounds in plants including fodder. The main causes that contribute to the nitro intoxication of animals are: non-compliance of the rules for the storage and use of nitrogen fertilizers, lack of zooveterinery control over the quality of forage containing amounts that exceed ALC. The most sensitive to nitro intoxication are ruminants. The degree of nitrate hazard is determined, mainly, by the total toxicity of all metabolites formed in the fermentation process in the multichamber stomach at ruminant animals. Nitro intoxication of animals occurs as a result of penetration of nitro compounds into the body with food and drinking water containing nitrites and nitrates that exceed ALC. The use in feed ration of animals, forage and water with a high nitrite and nitrate content causes acute or chronic toxicities, which diminishes the sanitary and biological quality of animal products.