The sanitary-hygienic laboratory of the branch of the Republican State Enterprise on the REM "National Center of Expertise" in the city of Almaty conducts research on crop products (in vegetables, fruits, and gourds) for nitrates and pesticides.

To date, the laboratory is equipped with modern instruments that allow determining with a high degree of accuracy the residual amounts of organochlorine and organophosphorus pesticides.

So, for 6 months of 2018, 786 samples of food and animal origin were examined for the content of pesticides. Basically, organochlorine pesticides were found that did not exceed the maximum allowable concentration (MAC). These are potatoes, carrots, cabbage, cucumbers, lemon, cherries, in meat products and cereals. For example, 0.01 mg/kg at a rate of 0.1 mg/kg, 0.06 mg/kg at a rate of 0.5 mg/kg, 0.02 mg/kg at a rate of 0.1 mg/kg, 0.02 mg/kg at a rate of 0.5 mg/kg, 0.02 mg/kg, 0.03 mg/kg, 0.003 mg/kg, 0.006 mg/kg at a rate of 0.1 mg/kg.

Also, for 6 months of 2017, 630 samples of crop products were examined, of which 10 were found to exceed the permissible limits (onions, cucumbers, tomatoes, carrots), which amounted to 1.6% of the total number of products studied for this year. In 2018, for the same period, 621 samples of crop products were examined - vegetables and fruits, melons. According to the results of studies in 13 samples (melon, onion, beetroot, cherry, tangerine, apricot, peach, strawberry, lemon), an excess of nitrate content by 2.1% of the total amount of the studied products was found. That is, in comparison with 2017, we are seeing an increase in the discrepancy by 0.5%.

Pesticides are the only pollutant that is deliberately introduced into the environment by man. Pesticides are plant protection chemicals used to control pests and diseases of plants, weeds, pests of grain and grain products, wood, cotton products, wool, leather, ectoparasites of domestic animals, as well as vectors of dangerous human and animal diseases. However, like any chemicals, pesticides are harmful. They affect various components of natural ecosystems: they reduce the biological productivity of phytocenoses, the species diversity of the animal world, reduce the number of beneficial insects and birds, and ultimately pose a danger to humans.

Nitrates - salts of nitric acid, are an element of plant nutrition and a natural component of food products of plant origin. Their high concentration in the soil is absolutely non-toxic to plants, but they are precursors of N-nitroso compounds that have a carcinogenic effect, that is, they predispose to the development of oncological diseases. The intake of increased amounts of nitrates in the body can lead to a significant impairment of health, and the excessive accumulation of nitrates in agricultural products of plant origin is accompanied by a decrease in their nutritional value: the content of vitamins, carbohydrates, amino acids decreases, the micro- and macroelement composition of products changes, etc. It is also possible to accumulate toxic and carcinogenic compounds, in particular, heavy metals, nitrosamines and radionuclides.

In case of violation of the regulated conditions for long-term storage of products containing high amounts of nitrates, there is an accumulation in them of nitrites and secondary amine derivatives that are more hazardous to health, accompanied by an intensive loss of consumer properties.

Құdayberdi Marzhan Daukenkyzy

high-tech research specialist

Sanitary and Hygienic Laboratory of the NCE Branch in Almaty