Researchers have discovered how the aftermath of the Chernobyl disaster affects products from Kaluga.

The Chernobyl tragedy of 1986 still resonates with the residents of the Kaluga region. This issue is particularly relevant for the Ulyanovsk district, located 100 kilometers south of Kaluga.

Residents of the Ulyanovsk district primarily engage in maintaining personal subsidiary farms, cultivating vegetables and fruits for sale at local fairs and markets. According to the decree of the Government of Russia dated October 8, 2015, 14 populated areas in three districts of the Kaluga region have been assigned the status of "residential zone with the right to resettlement," while 284 populated areas in nine districts have been classified as "residential zone with preferential social status."

In September 2023, scientists from the RUDN University named after Patrice Lumumba, in collaboration with researchers from MTUCI, organized an expedition to the Ulyanovsk district of the Kaluga region. The objective of the expedition was to collect samples of plant-based food products for analysis of radionuclide content and to compare the obtained data with hygiene standards. Particular attention was given to two of the most hazardous radionuclides—cesium-137 and strontium-90—which serve as indicators of radioactive contamination. These radionuclides pose a significant threat due to their long half-lives (up to 30 years) and their ability to accumulate in the tissues of animals and plants.

Measurements of the specific activity of gamma radiation from cesium-137 and beta radiation from strontium-90 in two samples of potatoes and carrots were conducted in the laboratory of the "Ecology" department at MTUCI using the MKS-01A "MULTIRAD" spectrometric installation, equipped with the "MULTIRAD-gamma" gamma spectrometric channel and the "MULTIRAD-beta" beta spectrometric channel with "Progress" software.

The research results indicated that the cesium-137 content in all samples was approximately 20 times lower than the normative value (SanPiN 2.3.2.1078-01). However, the situation with strontium-90 is ambiguous: in all studied samples, its content exceeded the allowable level (40 Bq/kg).

“The specific activity of strontium-90 in the examined potato samples exceeds the established norm (40 Bq/kg) by about two times. In one of the samples, the maximum value reached 165.8 ±5 Bq/kg, which is more than four times the permissible level set by SanPiN 2.3.2.1078-01,” notes Victoria Erofeeva, Candidate of Biological Sciences, Associate Professor, and Head of the "Ecology" department at the Faculty of KiIB at MTUCI.

The study demonstrates that even decades after the disaster, monitoring the quality of agricultural products in regions affected by the Chernobyl accident cannot be relaxed. Cesium-137 has a half-life of about 30 years, while strontium-90 has a half-life of approximately 28.8 years, leading to their prolonged presence in the environment.

To optimize the radiation situation in the area, specialists propose implementing comprehensive protective measures aimed at reducing the radionuclide content in soil and products. For instance, modern agrochemical methods can be applied: the introduction of phosphorus and potassium fertilizers, the use of micronutrients, adjustments to the nitrogen nutrition of plants, and liming of soils. The application of micronutrients (boron, molybdenum) and soil liming also effectively limits the uptake of radionuclides by plants. These methods help reduce the absorption of radionuclides by plants and contribute to the restoration of soil fertility.

Scientists also suggest the mechanical removal of the topsoil (a labor-intensive and costly method) or, as an alternative, deep plowing of contaminated areas. Deep plowing, coupled with burying the uppermost, most contaminated layer of soil to a depth of 40–60 centimeters or deeper, allows for the displacement of radionuclides from the upper layer to the lower horizons, where only a few plant roots can penetrate.

Regular monitoring of the radiation background of the harvest and providing the population with up-to-date information about the state of the environment and the safety of the grown products are also necessary. Each of these measures requires a systematic approach and long-term efforts from the government, the scientific community, and local residents.

The scientists' article was published in the journal "Innovative Technologies in the Agro-Industrial Complex: Theory and Practice."