АIR POLLUTION EMISSIONS ARE ASSOCIATED WITH INCIDENCE AND PREVALENCE OF BREAST CANCER IN THE AKTOBE REGION OF WESTERN KAZAKHSTAN.

Purpose - to establish a relationship between the incidence and the prevalence of breast cancer and air emissions of pollutants in the Aktobe region of the Republic of Kazakhstan.A retrospective study of the database was carried out on the territory of the Aktobe region of Western Kazakhstan. The data were obtained from the Register of Oncological Diseases of the Aktobe Regional Cancer Center. Data on air emissions for 2014-2019 were obtained from the Annual Statistical Bulletin "Environmental statistics. On the state of protection of atmospheric air in Kazakhstan" of the Committee on Statistics of the Republic of Kazakhstan.Breast cancer ranks is first among the malignant oncological pathology of women in the Aktobe region in 2019 and is 20.5% (95% CI 19.6-21.4) of all cancer cases. The analysis shows that the incidence and prevalence of breast cancer in 2014-2019 continues to grow: incidents from 37.3 (2014) to 56.0 (2019) per 100,000 population, the growth rate is 8.3%; prevalence: from 274.0 (2014) to 344.8 (2019) per 100,000 population, the growth rate is 4.7%. Spearman's rank correlation analysis showed a strong direct relationship between benzene emissions and the incidence (r=0.8, p=0.027). A direct strong relationship was found between the prevalence of breast cancer and the amount of emissions into the atmosphere (r=0.8, p=0.027), carbon monoxide (r=0.9, p=0.037), nitrogen oxides (r=0.9, p=0.037), lead (r=0.8, p=0.021), hexavalent chromium (r=0.6, p=0.048), xylene (r=0.7, p=0.047), toluene (r=0.8, p=0.034), methanol (r=0.8, p=0.040), butyl acetate (r=0.7, p=0.046).The unfavorable environmental situation in the Aktobe region associated with the release of chemical pollutants and heavy metals can contribute to the development of cancer. The revealed correlation between the prevalence of breast cancer and the release of chemical elements into the atmosphere requires further study to determine risk factors for breast cancer in the region of Western Kazakhstan.

ASSESSMENT OF ADEQUATE IODINE AVAILA-BILITY TO THE POPULATION OF WEST KAZAKHSTAN BASED ON THE DATA OF INORGANIC IODINE IN URINARY EXCRETION.

Aim of research - to study the iodine supply of the region according to the degree of urinary iodine excretion in the West region of the Republic of Kazakhstan. Of 6493 schoolchildren participating in the study of the frequency of goiter, random sampling was applied to select 884 children to determine UIC. To establish the excretion of inorganic iodine in a single portion of urine in the field, express diagnostics, the "Iodine test" kits (manufactured in Ukraine), was applied. The collection of urine for the determination of UIC was carried out in disposable cups, hermetically sealed with stoppers to prevent the entry of iodine vapors into the test samples. The test was carried out immediately after urine collection. The concentration of iodine in the urine was expressed in µg/l. The method is semiquantitative and makes it possible to distinguish urine samples with iodine content below 70, from 70 to 100, from 100 to 300 and above 300 µg/L. The obtained data on the study of UIC in schoolchildren in the West Kazakhstan showed that the proportion of children with optimal urinary excretion of iodine (100-300 µg/L) is 62.67% (95% CI: 59.48-65.86%). Indices ranging from 100 to 200 µg/L were detected in 27.15% (95% CI: 24.22-30.08%, more than 200 µg/L and up to 300 µg/L - in 35.52% (95% CI: 32.37-38.68%) of schoolchildren. UIC exceeds 300 µg/L - in 18.89% (95% CI: 16.31-21.47%) of schoolchildren. Concentration of iodine in the urine of more than 400 µg/L was determined in 1.81% (95% CI: 0.93-2.69%) of children. Low excretion rates of iodine, less than 70 µg/L, were detected in 2.83 % (95% CI: 1.74-3.92%) of schoolchildren, and from 70 µg/L to 100 µg/L - in 13.8 % (95% CI: 11.53-16.07%). Thus, in 62.67% (95% CI: 59.48-65.86%) there is an optimal allocation of iodine in the urine, it can be considered that iodine status of the population of West Kazakhstan is adequate. In West Kazakhstan, in the absence of iodine deficiency, a strained goiter endemia remains.The formation of goiter endemia in the region does not exclude the influence of other strumogenic factors, which need further study.

[MICROELEMENT STATUS IN CHILDREN WITH ENLARGED THYROID GLAND IN WEST KAZAKHSTAN REGION].

Aim of research - analysis of content of microelements in hair of children with thyromegaly living in the West Kazakhstan region. 159 school children of 6-12 years constantly living in this region were studied. Thyroid volume was measured by ultrasonography using an ultrasound scanner and evaluated according to body surface area and the gender in accordance with the WHO recommendations (2007). Microelements were measured by inductively coupled plasma mass spectrometry on NexION 300D (PerkinElmer Inc., USA). Excess value of the content of boron at 32.29% and silicon at 21.44% was found in children with goiter compared with those from control group. There was a reduction of cadmium at 37.38%, manganese - 26.48%, lead - 47%, vanadium - 15.5% compared with children with the normal volume of the thyroid gland. Correlation analysis showed a positive association of thyroid volume and hair trace elements Cu (r=0.423; p=0.001) and Si (r=0.202; p=0.01) and between I in hair and Hg (r=0.2978; p=0.001). The results of the multiple regression analysis revealed that the amount of thyroid is positively related to the concentration of copper and silicon in hair, and in less degree negatively with vanadium. The effect of these elements is 23%. Also found a positive dependence of iodine in the hair from indicators of mercury and negative from beryllium. Children with goiter show increased content of boron and silicon in hair and the decreased level of cadmium, manganese, lead, vanadium. The content of iodine in hair of children depends on the indicators of mercury and beryllium.