Cancer Incidence in a Population Living Near Radioactive Waste Storage of Uranium Mining in Stepnogorsk Area, Northern Kazakhstan.

OBJECTIVE: This study evaluates the impact of radioactive uranium waste storage facilities on cancer occurrence in nearby areas. METHODS: Current research evaluates the effect of radioactive uranium waste storage facilities on cancer epidemiology in nearby areas. The critical area had Aqsu, Kvartsitka, Zavodskoy and Stepnogorsk cities, which are located at a less than 5 km distance to the south of the Hydrometallurgical Plant tailings dump while the control group had Akkol region in 90 km from the source. The majority of population had lived in this territory more than the 30 years. Data were obtained from the Electronic Register of Cancer Patients of the Republic of Kazakhstan from 2001-2015, and 2,271 incident cases of cancer were registered. RESULTS: The most frequent malignancies were observed in the digestive organs (646 cases, 28%) and respiratory and intrathoracic organs (376 cases, 17%). The proportion of digestive organ cancers was higher in the critical group (560 cases out of 1913, 29%) than in the control group (86 cases out of 358, 24%). Additionally, respiratory organ cancers were more common in men, but the cancer incidence rate ratio was higher in the critical area. Notably, the study found that the cancer incidence rate ratios decreased over time, specifically for digestive, respiratory and female genital organs and breast cancer. CONCLUSION: In conclusion, while our study highlights significant differences in cancer incidence rates and frequencies between the critical and control groups, further analytical research, incorporating age-adjustment, is needed to provide a more conclusive evaluation of the potential impact of residence in proximity to the uranium mining waste storage on cancer occurrence in the study area.

Refining the evolutionary tree of the horse Y chromosome.

The Y chromosome carries information about the demography of paternal lineages, and thus, can prove invaluable for retracing both the evolutionary trajectory of wild animals and the breeding history of domesticates. In horses, the Y chromosome shows a limited, but highly informative, sequence diversity, supporting the increasing breeding influence of Oriental lineages during the last 1500 years. Here, we augment the primary horse Y-phylogeny, which is currently mainly based on modern horse breeds of economic interest, with haplotypes (HT) segregating in remote horse populations around the world. We analyze target enriched sequencing data of 5 Mb of the Y chromosome from 76 domestic males, together with 89 whole genome sequenced domestic males and five Przewalski's horses from previous studies. The resulting phylogeny comprises 153 HTs defined by 2966 variants and offers unprecedented resolution into the history of horse paternal lineages. It reveals the presence of a remarkable number of previously unknown haplogroups in Mongolian horses and insular populations. Phylogenetic placement of HTs retrieved from 163 archaeological specimens further indicates that most of the present-day Y-chromosomal variation evolved after the domestication process that started around 4200 years ago in the Western Eurasian steppes. Our comprehensive phylogeny significantly reduces ascertainment bias and constitutes a robust evolutionary framework for analyzing horse population dynamics and diversity.

Residential radon exposure in Astana and Aqsu, Kazakhstan.

A pilot study was carried out to measure indoor radon concentrations in a uranium mining area of northern Kazakhstan. A total of 80 places at kindergartens, elementary schools, and dwellings were selected in Aqsu village and Astana city as the uranium mining area and background area for comparison, respectively. In Astana and Aqsu, the 3-month radon concentrations from late summer to autumn in 2022 were measured using the RADUET passive radon detectors. Radon concentrations ranged from 4 to >2000 Bq m-3(mean ± standard deviation: 290 ± 173 Bq m-3) throughout the study areas. The concentrations were higher in Aqsu, and 70% of the dwellings there exceeded 300 Bq m-3, whereas only 5% of them exceeded 300 Bq m-3in Astana. Accordingly, the new dose conversion factor for radon recommended by International Commission on Radiological Protection Publication 137 was applied to calculate the annual effective dose. The annual effective dose from the inhalation of radon was estimated to be 3.6 ± 4.6 mSv y-1for Astana and 23.7 ± 15.6 mSv y-1, for Aqsu, which are both higher than the world average value of 2.5 mSv y-1.

Epidemiology of Somatic Diseases and Risk Factors in the Population Living in the Zone of Influence of Uranium Mining Enterprises of Kazakhstan: A Pilot Study.

The increase in uranium mining in Kazakhstan has brought with it a number of problems. Reducing the negative impact of radiation-toxic factors on the health of workers and the population in uranium mining regions is one of them. This article presents a pilot population health study in which we developed approaches to support residents living near an operating uranium mining enterprise. The purpose of the current study was to assess the impact of technogenic factors on the health of those living near the Syrdarya uranium ore province. Data collected from 5605 residents from the village of Bidaykol (the main group)-which is located 4 km from the uranium mining enterprise-and the village of Sunakata (the control group), which is located in the Kyzylorda region, were analyzed. A bidirectional cohort study was conducted. The prevalence of acute and chronic diseases among the residents of Bidaykol was 1.3 times higher than that in the control group. The structure of morbidity was dominated by pathologies of the genitourinary system (27%), the circulatory system (14.4%), and the respiratory system (11.9%). Relative risks (RR > 1) were identified for most classes of diseases, the highest being for diseases of the blood (RR = 2.6), skin (RR = 2.3), and genitourinary system (RR = 1.9). In the main group, renal pathologies were the most frequent class in the age group of 30-40 years, occurring mainly in women. In addition, they had a direct dependence on the duration of residence in the territory of the uranium ore province. Further studies into the interaction between the technogenic factors associated with uranium mining enterprises and the development of diseases of the urinary system are needed. This will make it possible to determine ways to prevent these pathologies in the population.

STUDIES ON GAMMA DOSE RATES IN OUTDOOR ENVIRONMENT AND ASSESSMENT OF EXTERNAL EXPOSURE TO PUBLIC IN STEPNOGORSK AREA, NORTHERN KAZAKHSTAN.

The present study is based on a pilot study, which showed that the Stepnogorsk area of Northern Kazakhstan represents sources of potential contamination of the living environment. The aim of the study was measurement of outdoor gamma radiation levels, activity concentration in soil samples and assessment of external exposure to the public. According to our analysis, the highest ${\boldsymbol{H}}^{\ast}$(10) values ∼2870 nGy h-1 were detected in the Aqsu school territory, which were slightly higher than the control readings for this region. The average 226Ra, 232Th and 40K activities were 617.8 ± 3.2 Bq kg-1, 188.3 ± 2.9 Bq kg-1 and 731.5 ± 6.2 Bq kg-1, respectively. The annual effective dose received by the Aqsu population ranged from 0.08 to 3.5 mSv y-1, which was found higher by an order of magnitude than the upper annual dose limit. Changes in radiation background are an unfavourable factor for the population and may possibly become potential radiation risks for long-term effects.

Geographical contrasts of Y-chromosomal haplogroups from wild and domestic goats reveal ancient migrations and recent introgressions.

By their paternal transmission, Y-chromosomal haplotypes are sensitive markers of population history and male-mediated introgression. Previous studies identified biallelic single-nucleotide variants in the SRY, ZFY and DDX3Y genes, which in domestic goats identified four major Y-chromosomal haplotypes, Y1A, Y1B, Y2A and Y2B, with a marked geographical partitioning. Here, we extracted goat Y-chromosomal variants from whole-genome sequences of 386 domestic goats (75 breeds) and seven wild goat species, which were generated by the VarGoats goat genome project. Phylogenetic analyses indicated domestic haplogroups corresponding to Y1B, Y2A and Y2B, respectively, whereas Y1A is split into Y1AA and Y1AB. All five haplogroups were detected in 26 ancient DNA samples from southeast Europe or Asia. Haplotypes from present-day bezoars are not shared with domestic goats and are attached to deep nodes of the trees and networks. Haplogroup distributions for 186 domestic breeds indicate ancient paternal population bottlenecks and expansions during migrations into northern Europe, eastern and southern Asia, and Africa south of the Sahara. In addition, sharing of haplogroups indicates male-mediated introgressions, most notably an early gene flow from Asian goats into Madagascar and the crossbreeding that in the 19th century resulted in the popular Boer and Anglo-Nubian breeds. More recent introgressions are those from European goats into the native Korean goat population and from Boer goat into Uganda, Kenya, Tanzania, Malawi and Zimbabwe. This study illustrates the power of the Y-chromosomal variants for reconstructing the history of domestic species with a wide geographical range.

Genetic characterization of Kushum horses in Kazakhstan based on haplotypes of mtDNA and Y chromosome, and genes associated with important traits of the horses.

The Kushum is a relatively new breed of horses in Kazakhstan that was established in the middle of the 20th century through a cross between mares of Kazakhstan local horses and stallions of Thoroughbred, Trotter, and Russian Don breeds to supply military horses. To reveal the genetic characteristics of this breed, we investigated haplotypes of mitochondrial DNA (mtDNA) and single-nucleotide polymorphisms of the Y chromosome, as well as genotypes of five functional genes associated with coat color, body composition, and locomotion traits. We detected 10 mtDNA haplotypes that fell into 8 of the 17 major haplogroups of horse mtDNA, indicating a unique haplotype composition with high genetic diversity. We also found two Y-chromosomal haplotypes in Kushum horses, which likely originated from Trotter and/or Don breeds. The findings regarding the mtDNA and Y-chromosomal haplotypes are concordant with the documented maternal and paternal origins of the Kushum horses. The allele frequencies of ASIP, MC1R, and MATP associated with coat color were consistent with the coat color variations of Kushum horses. The allele frequencies of MSTN associated with endurance performance and those of DMRT3 associated with gait suggested that the observed allele frequencies of these genes were the result of selective breeding for these traits. As a result of this study, we were able to obtain useful information for a better understanding of the origin and breeding history of the Kushum horse breed using molecular markers.

Site-specific concentration of uranium in urine of workers of the hydrometallurgical plant of Stepnogorsk mining and chemical combine.

Radiation monitoring is an important radiation safety measure implemented at the hydrometallurgical plant of the Stepnogorsk mining and chemical combine (HMP SMCC, Republic of Kazakhstan). Follow-up of the workers and their regular medical examinations has laid the basis to create a cohort with the potential to be used in radiation epidemiology. The aim of current pilot study was to analyze the dose forming factors for workers of HMP SMCC. For this, bioassays samples collected from 54 workers employed at eight HMP workshops were measured using the "Agilent 7800 ICP-MS" mass spectrometer. Three years later, measurements were repeated for four workers with the highest concentrations of uranium in urine. The results of site-specific measurements of dose rates, long-lived alpha-particle activity concentrations and equivalent equilibrium volume activity of radon were derived from the archive of the HMP SMCC Service of Radiation and Toxic Safety and analyzed to fully evaluate the radiation situation at those workplaces. Maximum urine uranium concentrations were measured for workers at the extraction workshop and mechanical repair shop (up to 26.7 µg/L and 14.6 µg/L, respectively). Urinary uranium from workers employed at other sites was mainly (for about 72% of the samples) in the range of values that may occur in natural conditions (< 0.4 µg/L). A wide individual variability in uranium concentration in urine samples (from 60% to 200% of CV) was found. A linear dependence of cumulative effective dose on work experience was found with a slope of 7.5 mSv per year. This slope did not depend on working place. For the investigated workers, cumulative effective doses of workers were found in the range of low (< 100 mSv) and medium doses (100-500 mSv). It is concluded that the newly created cohort of HMP SMCC workers has the potential to improve the knowledge on health effects from low- and medium doses of ionizing radiation.

RADIATION SITUATION IN THE TERRITORIES AFFECTED BY MINING ACTIVITIES IN STEPNOGORSK AREAS, REPUBLIC OF KAZAKHSTAN: PILOT STUDY.

The Republic of Kazakhstan has a long history of mining activities, viz., gold and uranium. Mining activities represent sources of potential naturally occurring radionuclides contamination of the environment and human health of population. The aim of this study was to investigate the radiation situation of industrially modified environment in Stepnogorsk areas of Kazakhstan to understand the sources of contamination. Quite high values of ambient equivalent dose rates in air ~2.87 µSv h-1 were found in the Aqsu gold-mining site. The radon equivalent equilibrium volume activity (indoor) were in the range of 313-858 Bq m-3 in the study area buildings. The high values of activity concentration of natural radionuclides found in Aqsu soil samples were 226Ra-4060, 232Th-1170 and 40K-4080 Bq kg-1, respectively. However, our comprehensive surveys implied that the increased natural radiation background caused by the radionuclide transport from the tailing area did not have an impact, while evaluation of its potential radiation risks and remediation of the territories of the former gold mining should be needed.

Absence of mutations in the human interferon alpha-2b gene in workers chronically exposed to ionising radiation.

Individuals chronically exposed to low-level ionising radiation (IR) run the risk of harmful and long-term adverse health effects, including gene mutations and cancer development. The search for reliable biomarkers of IR exposure in human population is still of great interest, as they may have a great implementation potential for the surveillance of occupationally exposed individuals. In this context, and considering previous literature, this study aimed to identify mutations in the human interferon alpha-2b (hIFNα-2b) as a potential biomarker of occupational chronic low-dose IR exposure linking low-IR exposure to the effects on haematopoiesis and reduced immunity. The analysis was performed in the genomic DNA of 51 uranium miners and 38 controls from Kazakhstan, and in 21 medical radiology workers and 21 controls from Italy. hIFNα-2b gene mutations were analysed with the real-time polymerase chain reaction (PCR) or Sanger sequencing. However, none of the investigated workers had the hIFNα-2b mutation. This finding highlights the need for further research to identify biomarkers for early detection of health effects associated with chronic low-dose IR exposure.

Kazakhstani native cattle reveal highly divergent mtDNA from Bos taurus and Bos indicus lineages with an absence of Bos indicus Y chromosome.

Kazakhstan is the largest landlocked country and contains two important propagation routes for livestock from the Fertile Crescent to Asia. Therefore, genetic information about Kazakhstani cattle can be important for understanding the propagation history and the genetic admixture in Central Asian cattle. In the present study, we analyzed the complete mtDNA D-loop sequence and SRY gene polymorphism in 122 Kazakhstani native cattle. The D-loop sequences revealed 79 mitochondrial haplotypes, with the major haplogroups T and I. The Bos taurus subhaplogroups consisted of T (3.3%), T1 (2.5%), T2 (2.5%), and T4 (0.8%) in addition to the predominant subhaplogroup T3 (86.9%), and the Bos indicus subhaplogroup of I1 (4.1%). Subsequently, we investigated the paternal lineages of Bos taurus and Bos indicus, however, all Kazakhstani cattle were shown to have Y chromosome of Bos taurus origin. While highly divergent mtDNA subhaplogroups in Kazakhstani cattle could be due to the geographical proximity of Kazakhstan with the domestication center of the Fertile Crescent, the absence of Bos indicus Y chromosomes could be explained by a decoupling of the introgression dynamics of maternal and paternal lineages. This genetic information would contribute to understanding the genetic diversity and propagation history of cattle in Central Asia.

The Eurasian Steppe is an important goat propagation route: A phylogeographic analysis using mitochondrial DNA and Y-chromosome sequences of Kazakhstani goats.

Goats (Capra hircus) were domesticated in the Fertile Crescent and propagated all over the world. The Silk Road through the Eurasian Steppe belt is a possible propagation route for domestic goats to Central Asia. Kazakhstan is in close geographical proximity to domestication centers and covers the majority of the Eurasian Steppe belt. In this study, we examined the genetic diversity and phylogeographic structure of Kazakhstani goats. The mtDNA sequences of 141 Kazakhstani goats were categorized into haplogroups A, C, and D, of which haplogroup A was predominant (97%), whereas haplogroups C and D were detected at low frequencies (1.4% each). The Kazakhstani haplotypes C were thzen categorized into Asian mtDNA type. Sequence analysis of the SRY gene on the Y-chromosome in 67 male Kazakhstani goats revealed two haplotypes: Y1A (64%) and Y2A (36%). Analysis of the distribution of mtDNA haplogroups and SRY haplotypes from Eurasia and Africa demonstrated genetic similarity among animals from Kazakhstan, Mongolia, and Northwest China located on the Eurasian Steppe belt. These phylogeographic results suggested that the Eurasian Steppe belt was an important propagation route for goats to Central Asia.