Introduction. Various copper compounds are most widely used as plant protection agents in agriculture. From a hygienic point of view, information on excessive accumulation of copper in plants related to the use of a specific formulation of copper-containing pesticides is of interest. Our objective was to assess feasibility of increasing statistical significance of results of determining low residue levels of a copper-containing pesticide in apple samples by flame atomic absorption spectrometry using a high-resolution spectrometer in combination with developed approaches to sample preparation of plant-based foods, including homogenization with dry ice and microwave mineralization. Materials and methods: We analyzed 30 samples of apples collected in three different agro-climatic zones by flame atomic absorption spectrometry and electrothermal atomization atomic absorption spectrometry. Both methods were validated on 10 samples with added copper at levels 1-5 of the lower limit of quantitation. A statistical calculation was performed based on a simple Student’s test to assess the significance of differences between the results of measurements by flame and electrothermal techniques. Homogeneity of variances was estimated using the Fisher test to clarify the possibility of comparing two data sets. Results: The use of a technique of cryo-grinding and microwave decomposition in a microwave reactor in combination with a high-resolution continuum source atomic absorption spectrometry demonstrated a decrease in scattering and the limit of detection and better repeatability in the analysis of parallel samples. Results of statistical calculations confirmed the homogeneity of variances in data samples obtained for electrothermal and flame techniques, and the further Student’s t-test showed insignificant differences between the results of measurements obtained by FAAS and ET-AAS. Conclusion: Our findings prove that modern methods of sample preparation in combination with highly sensitive equipment allow a significant reduction in the limit of detection and scattering of test results.

Relevance and methods. Methodological approaches to assessing the residual amounts of copper-containing pesticides in plant products against the background of natural copper content are presented. The conditions for obtaining reliable results when conducting a hygienic assessment of the content of residual amounts of the active substance are determined. The developed scheme for determining the residual amounts of copper-containing pesticides includes the homogenization of the analyzed material by shredding with dry ice and microwave mineralization of samples with subsequent flameless atomic absorption determination of copper.Results. Data on the levels of natural copper content in samples of potatoes, onions, cucumbers, tomatoes and grapes of various varieties and growing areas are presented. The possibility of applying the developed approaches to study the dynamics of accumulation of active substances during the growing season is shown.

There are presented methodological approaches to assess the risk of negative factors associated with characteristic areas of metallurgical enterprises in pollution of the environment with heavy metals to human health. The use of noninvasive biotesting, based on established correlations of indices of trace elements and oxidative status in the body is suggested. As a non-invasive biological material, alveolar moisture condensate from the person (expirate) is used. The basis for the health risk assessment is information on the balance of two components of the oxidative process responsible for the adaptive function of the body - free radical oxidation and antioxidant defense system. An imbalance of these processes contributes to the development of oxidative stress, the complication of the course of many diseases. The deviation in quantitative indices of a number of elements, primarily of metals of variable valency, which participate in reactions of lipid peroxidation, showing pro - or antioxidant properties can also serve as the indicator of the effects of complex heavy metals. The identified relationship of trace elements and oxidative status allows providing the approach to the assessment of processes of peroxidation in the assessment of microelement exchange indirectly. To study the intensity of peroxidation and capacity of the antioxidant defense system in expirate a number of methodological solutions was proposed - methods of chemiluminescence and spectrophotometry, as well as biotest, allowing detect deviations in the oxidative status and based on the level of bioluminescence of lyophilized bacteria by oxidative potential of investigated expirate of alveolar moisture. The complex of methods for assessment of the degree of the health risk associated with pollution by heavy metals can be used for screening observations in selected contingents with the purpose of formation of risk groups such as individually for the choice the optimal ways of correction of disorders and the assessment of the efficiency of preventive or corrective measures. Examples of methodological approaches in one of the regions of accommodation of the enterprises of nonferrous metallurgy, and in the estimation of risk development of pathological conditions and the efficiency of the treatment for a particular worker of the metallurgical plant, as the patient in the clinic of occupational diseases.

Introduction. Atmospheric aerosols contain many carcinogenic and toxic substances, a significant part of which is represented by heavy metals. Traditionally, metal analysis is preceded by air sampling on AFA-HA-20 filters; yet, the lack of regulations on permitted background levels of trace elements in the filter material may limit reliability of measurements. Selection of filters with similar technological parameters can be a way to improve analytical accuracy. Objective: To determine contamination of different types of filters and to establish its effect on the results of spectral analysis of airborne metal concentrations in a large industrial city. Materials and methods: We analyzed unexposed AFA-HA-20 filters and Merck Millipore MF filters (n = 30 each) for the content of 13 heavy metals identified as priority pollutants within the Federal Clean Air Project. To assess the effect of filter contamination on the analytical error, air sampling was performed by exposing Merck Millipore MF filters at mobile monitoring stations in the city of Lipetsk. The filters were then analyzed by inductively coupled plasma mass spectrometry with prior microwave mineralization. Results: Our findings confirm the repeatedly obtained data on metal contents in null AFA-HA-20 filters and indicate significantly lower levels of contamination of unexposed Millipore MF filters made of mixed cellulose ethers. Conclusions: The risk of obtaining false positive and false negative results depends on the level and variability of the content of a particular trace metal in the filter. The AFA-HA-20 type of filters traditionally used for ambient air sampling may itself confound measurement result.

Relevance. Study of pesticide residues is an integral part of registration tests. It is present a particular interest in terms of hygienic safety of eating vegetable crops grown with use of protective agents.Methods. The analysis procedure includes an approach developed by the authors, based on microwave digestion of samples after cryo-destruction, followed by analysis by atomic absorption spectrometry with electrothermal atomisation. The approaches used in research, allow us to trace the dynamics of copper content in fruits of potatoes, tomatoes, cucumbers and onions, during the vegetation periods of 2020-2021 in different soil and climatic zones.Results. It is shown that treatment with copper-containing preparations does not affect the content of copper in fruits of the studied crops during the whole experiment, except for the day of sampling immediately after the treatment. At the same time, reliable excesses in comparison with control samples are observed in experiments, where the aboveground part of crops is investigated. For example, the content of copper in tomato fruits in 2020, taken on the day of the last treatment, was 0.61±0.16 mg/kg and 0.47±0.08 mg/kg in the experimental and control samples, respectively. In 2021, the trend continued and copper concentration on the day of treatment was 0.80±0.15 mg/kg and 0.64±0.12 mg/kg respectively in the experimental and control samples. In the study of onion treated with copper oxychloride-based preparation, the concentration of copper in the whole plant (leaves + bulb) on the day of treatment in 2020 was 8.5±1.1 mg/kg in the experimental sample and 0.43±0.18 mg/kg in the control sample. In 2021, the copper concentration in the experimental sample collected on the treatment day was 14.1±3.8 mg/kg and in the control sample was 1.1±0.2 mg/kg respectively.