Nitrates - what is it? Nitrates: formula, receipt, application, action

Among the information on the problemcorrect nutrition, we can distinguish a segment that reveals the effect on the human body of substances such as nitrates. Their effect on our health is ambiguous. How not to recall the famous expression of Paracelsus: "Everything is poison and everything is a medicine; this or that does only a dose of it. " Indeed, for proper metabolism, the presence of anion NO in the cytoplasm of cells₃^- NO₄⁺. At the same time, the excess of compounds containingthese ions, in food is dangerous to human health. The role of nitric acid salts, their preparation, application of nitrates will be considered in this article.

The position of nitrates in the classification of inorganic substances

Many know that the salts of nitric acid are goodsoluble in water are nitrates. What is saltpeter is not known to everyone. It turns out that earlier in the chemistry called special substances - salts of nitric acid. So far we can hear this term applied to the chemistry of mineral fertilizers. In nitrates, nitrate ion is bound to potassium, calcium, sodium and ammonium cations. They are medium salts. It turned out that nitrates of sodium, potassium and other salts decompose on heating, and the reaction products depend on which cation is a part of the molecule. So, nitrates, the formula of which is KaNO₃ or NaNO₃, are thermally decomposed to the corresponding nitrite and free oxygen, and magnesium nitrate upon heating forms oxide, nitrogen dioxide and oxygen.

Getting nitrates

The main method is the processing of naturalminerals containing salts of nitric acid. Thus, Chilean nitrate, which is a mineral nitrone, is one of the main sources of their production. At the factories of the fat industry, rock containing sodium nitrate is finely ground and, in pre-packaged form, is supplied by the agricultural enterprises of the farm as a nitrogen fertilizer. Apply it primarily for the growth of the vegetative mass of vegetable, cereals and fruit and berry crops, as well as to increase their yield. Under laboratory conditions, nitric acid salts are obtained by an exchange reaction between alkali and nitrate acid or by the interaction of metals with concentrated HNO_3. The use of nitrogen fertilizers, such as potassium nitrate, ammonium nitrate, is a prerequisite for obtaining stable high yields of basic crops.

Agrotechnical conditions for the introduction of nitrogen fertilizers (nitrates)

They include, above all, compliance with standardsintroduction of drugs into the soil. For example, for ammonium nitrate containing up to 35% nitrogen, the allowable rate is not more than 25 g per square meter. Calcium nitrate, which includes up to 15.5% of nitrogen, is introduced at a rate of up to 50 g per 1 m. Violation of the agrotechnical norms of nitrogen fertilizing of plants not only leads to soil contamination and a decrease in its reducing function, but also to a dangerous concentration of compounds such as nitrates, in vegetables and fruits. We will dwell on this question further.

How nitrates get into plants

Let's consider, what exactly ways arrive insoil nitrates, what is pre-sowing, starting fertilizer and feeding. In agriculture, the main application of fertilizers is carried out in the spring and at the same time pay attention to the soil composition and climatic features. The goal is to ensure nitrogen nutrition during the vegetative period of the plant.

When using the starting method, niterare applied directly to the rows or wells, using nitrates in minimum doses to "not burn" the fragile roots of the planted seedlings. Feeding is carried out during the most intensive absorption of nutrients by plants. It is carried out in the form of vegetative crops or as a root dressing with solutions of nitrates. In the soil substrate, ammonium ions or nitrate ions are easily absorbed by the root hairs by diffusion and then go to xylem. It consists of conducting elements of plants. In gymnosperms it is tracheids, and in flowering ones - vessels (trachea). The nitrogen atoms that make up the nitrates are included in the Calvin cycle, which is carried out in the dark phase by photosynthesis, and later they are part of the synthesized amino acids and further into vegetable proteins.

The more dangerous is the excess content of nitrate salts

If the concentration of the above compoundsexceeds the permissible norm, this can be determined by the device for measuring nitrates in products. It is available on sale and is used in many families that are responsibly related to their health. Studies of medicine have proven that the excess of HNO salts₃ in the gastrointestinal the path turns into nitrite. They cause irritation of the mucous membranes of the stomach and duodenum, symptomatically manifested by the phenomena of dyspepsia and food poisoning. It was also found that the excess of HNO salts₂ poor kidney output, so theyaccumulate in the renal parenchyma. It is known that the kidneys themselves play a leading role in metabolism and the removal of harmful metabolic products. Reduction of the filtration function of the kidneys is a very dangerous complication resulting from poisoning with salts of nitrogen and nitrous acids. As a result of eating foods with a high content of nitrates, the liver, which is another detoxifying organ, also suffers. Its damage with nitrates is fraught with severe damage right up to the degeneration of hepatocytes into adipose tissue.

Oxygen starvation of tissues as a consequence of their poisoning with nitrates

Nutrients (fats, carbohydrates) canThey are stored as a spare source of energy and are expended by the body gradually. That's why a person is able to do without food for 5-7 days. But oxygen, unlike carbohydrates and fats, can not last long in cells or tissues, so hypoxia for 5-15 minutes leads to the death first of the brain cells, and then of the entire human body as a whole. Seemingly innocuous, nitrates in fruits, vegetables, milk infant formulas can cause the destruction of respiratory chains in the mitochondria, disrupt the formation of the binding of the erythrocyte pigment - hemoglobin - with oxygen molecules.

And to prevent its transfer to organs and tissues. Therefore, the excess concentration in the cytosol of cells of compounds such as nitrates (formula - Me (NO₃) N_1), can lead to serious impairment of functions on the part of such physiological systems as digestive, excretory, and also nervous.

Which products can be contaminated with nitrate acid salts

In most people, the surplus content of thesesubstances is associated with vegetables or fruits, such as watermelon, potatoes, radish or strawberries. But it turns out that the pollution of the soil and especially water with nitrogen fertilizers that got there due to a violation of the norms of their application directly leads to "subsidence of nitrates" in the organisms of domestic animals. Therefore, the uncontrolled and irrational use of nitrates entails their high content in livestock products: meat, milk and even honey. Spraying of plants-honey plants (buckwheat, rape) with solutions of nitric acid salts as a liquid fertilizer leads to the appearance of toxins in bee products.

How to determine the content of nitric acid salts in products

Let's clarify how it is practically possible to learnon the concentration of nutrients in compounds such as nitrates. What is a nitrate tester, consider in more detail. To detect the presence of nitric acid salts, it is necessary to immerse the instrument probe in the pulp of a watermelon or other product. The device has two parts: positive and negatively charged. And the nitrate meter itself determines the electrical conductivity of the cell-juice solution. The obtained results are compared with the MPC of the product under investigation, and the device for measuring nitrates in products displays a result with the content of salts in mg / kg. Especially desirable is the testing of food products used in the nutrition of young children, pregnant and lactating women, as well as people suffering from chronic gastrointestinal and renal diseases.

Nitric acid salt poisoning and its prevention

The peak of recorded cases of intoxication,associated with poisoning with salts of nitric acid, is carried out at the end of winter - the beginning of spring. Due to the lack of sunlight and energy, the human body during this period is in dire need of vitamins contained in fresh vegetables and fruits. Therefore, supermarkets do not contain greenhouse cucumbers, tomatoes, spicy flavors (celery, parsley, dill), as well as strawberries. Agrotechnologies for their cultivation require the mandatory use of substances such as nitrates. What is mineral fertilizers and how their excess affects the human body, has already been considered by us earlier. Now we will focus on first aid measures that can alleviate the condition of a patient with symptoms of nitrate poisoning. First of all, you need to induce vomiting to remove from the stomach a toxic product. To do this, drink abundantly. Then take drugs-enterosorbents and continue to comply with water-salt regime. With complex symptoms such as a drop in blood pressure, loss of consciousness, seizures caused by central nervous system damage and kidneys, an "ambulance" should be urgently called.