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KNOWLEDGE OF NITRATES
Nitrate is saline of nitrogen acid most widespread substance in nature.
Nitrates take place in a ground, water, they are the chemical components of plants, products of substances’ exchange in organism of human and animal. People experience nitrates influence during living all the time. However, in case when loading of these substances on an organism is too heavy they can have a negative effect.
There’re known over 20 factors able to bring to increased nitrates accumulation in vegetative food. They concern to: light deficit, heat and cold in plants vegetation period, drought and constant overly humidifying, large and small amount of such elements as nitrogen, potassium, phosphorum in a ground, biological activity of a ground, ground acidity, ground disease etc. But the primary factor stays non-rational applying of nitrogen fertilizers, violation of agrotechnic processing agricultural cultures.
The problem of nitrates has arisen due to use of mineral fertilizers containing nitrogen:
potassium niter KNO3;
natrium niter NaNO3;
ammoniac niter NH4NO3.
Such important components as protein, fat, carbohydrate, vitamins and other, and also various chemical substances: pesticides, toxic elements, nitrates and other take place in foodstuffs. Contents of chemical substances in food can vary in wide range: from concentration safe for people, to their level which represents actual danger for health. Nitrates serve as the obligatory part of foodstuffs, but their amount should stay in acceptable limits of concentration.
The problem of nitrates has two aspects: which are interconnected but have some features. It is the aspect of nitrates in potable water and aspect of nitrates containing in foodstuffs.
Nitrate is a toxic substance.
Intoxication by nitrates is characterized by heavy passing and can bring to lethal effects. Nitrates toxic action consists in hypoxia (deficiency in the amount of oxygen delivered to the body tissues).
Clinical indications of nitrates poisoning occur in 1 .. 1,5 hours after getting into an organism with potable water. At first period there’s cyanosis of lips, mucous membranes, nails and face observed. Then it comes sickness, stomach each, salivary emissions, vomiting. In case of nitrates getting into organism with food the latent period of disease is more prolonged - from 4 till 6 hours.
When there’s suspicion of poisoning by nitrates and nitrites patient gets:
1. stomach washing out,
2. taking suspension of activated carbon (2 spoons per glass of water),
3. salt laxative mixture.
The hygienic regulation of acceptable concentration provides the acceptable daily doze of nitrates. It makes 5 mg per 1 kg of body weight of a person.
Nitrates can be accumulated in the increased amount not only in vegetative food, but also in food of animal origin and first of all in milk.
Measures to reduce nitrate contents in food are described below.
10 % reduction is reached by usual washing and mechanical clearing of food (potatoes, beet, carrot, cabbage etc.).
25 .. 30% - 1 hour steeping of the cleaned food: potatoes, carrot, beet, greens, parsley, fennel, green onions.
Up to 80 % – by cooking potatoes; 60 .. 70 % - carrots and cabbage; 40 .. 50 % - beet.
While boiling they turn into broth and also into pickle or marinade as well.
Making juices and drying of fruits or vegetables, on the contrary, increases contents of nitrates.