PHOSPHATE FERTILIZERS MARKETED IN RUSSIA AS A SOURCE OF RARE EARTH ELEMENTS IN THE SOIL

Phosphate fertilizers actively used in agriculture can serve as a source of various impurities in the soil, which can have a negative impact on environmental components. In this work, the content of rare earth elements (REEs) in phosphate fertilizers marketed in Russia was evaluated. REEs are a group of elements that are actively studied due to possible negative and positive effects on living organisms. Currently, there are no standards for the content of REEs in soil and fertilizers. Also, in the literature there are no data on REEs content in phosphate fertilizers marketed on the territory of Russia and assessment of the significance of fertilizer application as a factor of REEs input into agricultural soils. Using the method of optical emission spectrometry with inductively coupled plasma, we obtained data on the REEs content in samples of phosphate rock, single and double superphosphate (22 samples). It is shown that phosphate fertilizers can differ significantly in REEs content, high REEs content (over 1000 mg/kg) was observed in some samples of single and double superphosphate. The group of phosphate rock samples is the most homogeneous in terms of REE content in the samples. Light REEs predominate over heavy REEs in the composition of fertilizers. According to the results of the study, it can be concluded that there is potentially no significant effect of the application of the studied phosphate fertilizers on the REEs content in the soil. However, the high REEs content in some fertilizer samples requires monitoring of REEs content in soils of agrocenoses, as well as the development of standards for REE content in mineral fertilizers. Funding. This work was supported by Russian Science Foundation grant No. 22-74-00003, https://rscf.ru/project/22-74-00003/.