Kaschin-Beck Disease Areas Research Articles

Research Progress of Drinking Water and Trace Elements in KBD Area

Kaschin-beck disease (KBD) is an endemic, chronic, and deformable osteochondral disease characterized by multiple degenerations and deep cell necrosis of epiphysis, epiphysis, and articular cartilage. The disease mainly affects children and adolescents aged 5-15, is concentrated in northeast and southwest China, involving 15 provinces, and extends into southeastern Siberia and North Korea. Although the etiology and pathogenesis of KBD are still not very clear, in recent years, more breakthroughs have been made in the supplement and update of its biogeochemical theory, especially in the analysis of hydrochemical characteristics and the study of the role of selenium and iodine in the pathogenic factors of KBD. Therefore, the present research results on the environmental geographical factors of Kashin-beck disease are reviewed in this paper.

Thermodynamic control on chemical weathering of river bedrock at the Aba and Qamdo in Kaschin-beck disease region, eastern Tibet Plateau

Groundwater is the main source of water for living and agriculture in an area. To investigate the relationship between water environment and Kaschin-beck disease (KBD), we collected published data on water samples (data from the KBD areas of Aba Prefecture, Qamdo area, the Yellow River Basin region and the non-KBD area of the Yangtze River Basin region) for thermodynamic simulations to further analyze the hydrogeochemical properties. The analysis results show that: (1) The groundwater in Aba Prefecture and Qamdo area is weakly alkaline. (2) The groundwater type in Aba Prefecture and Qamdo area is Ca-HCO3− type. (3) The average concentration of cations Mg2+and Ca2+ can be expressed as Yellow River Basin > Yangtze River Basin > Aba Prefecture > Qamdo area. The average concentration of cation Na+and anion Cl− can be expressed as Yellow River Basin > Qamdo area > Yangtze River Basin>Aba Prefecture. The value of TDS can be expressed as Yellow River Basin > Qamdo area > Yangtze River Basin > Aba Prefecture. This may indicate that there is no direct relationship between KBD and water environment. (4) The dissolution of calcite and dolomite in quartzite controls the change of element content of water. (5) Analysis of the Gibbs distribution shows that most of the elements in the groundwater of the KBD areas (Aba Prefecture, Qamdo area and the Yelllow River Basin region) and non-KBD area (the Yangtze River Basin region) majorly come from rock weathering. (6) The overall quality of groundwater is good, the salinity is low, and it is suitable for agricultural irrigation.

Differences of selenium and other trace elements abundances between the Kaschin-Beck disease area and nearby non-Kaschin-Beck disease area, Shaanxi Province, China

In order to find out the environmental geochemical characteristics of KBD affected area, KBD and non-KBD villages in KBD Counties, Weibei KBD area, Shaanxi Province, China were studied. Contents of Se and other elements in soil, wheat, maize and drinking water were analyzed. The results show that soil of Weibei KBD area is deficient in trace elements comparing with BSC and non-KBD area. Wheat of Weibei KBD area is deficient both in major elements and trace elements comparing with REC. Wheat of KBD village is especially deficient in Cr, Co, Se, Mo and Mg. Contents of Sr, Li and Mo in wheat of KBD village are significantly lower than nearby non-KBD village, but the average Se content is slightly higher. The deficiency of trace elements, especially Se, Sr, Li and Mo in staple food and trace elements in soil, is the main characteristic for the environment of KBD area.

Trace Element Levels in Scalp Hair of School Children in Shigatse, Tibet, an Endemic Area for Kaschin-Beck Disease (KBD).

Kaschin-Beck disease (KBD) is an endemic osteoarthritis, and the etiology is closely related with levels of trace elements in the human body. Currently, it is clear that the selenium (Se) status of children in KBD areas is lower than that in non-KBD areas in the Tibetan Plateau, whereas role of other elements are yet unknown. This study aimed to assess some essential trace elements (Se, Mo, Mn, Zn, Fe, Cu, Co, and Sr) in children using scalp hair as a biomarker, and 157 samples from school children aged 8-14years old were collected from both KBD and non-KBD areas in Shigatse, Tibet. Se and Mo were measured by inductive coupled plasma mass spectrometry, and the other elements were determined by inductive coupled plasma optical emission spectrometry. Compared with the non-KBD areas, Se, Mo, Mn, Fe, Zn, Co, and Sr levels of children in KBD areas were found to be significantly different (P<0.05); while in linear discriminant analysis, only Se and Zn were found to contribute to the KBD prevalence in the study area. The hair Se level of children in KBD areas ranged from 0.115 to 0.299mg/kg, while in non-KBD areas it ranged from 0.135 to 0.519mg/kg. The Zn content of children's hair was between 83 and 207mg/kg in KBD areas, while it was 37 and 219mg/kg in non-KBD areas. Lower Se and higher Zn levels in children in KBD areas was found when compared with non-KBD groups. In addition, Mo levels were found to be different between KBD areas and non-KBD areas on the opposite side of the Yarlung Zangbo River, but no close relationship was shown because there was no difference compared with the non-KBD area on the same side of the river. Our observations suggest that Se deficiency is still an important factor for the occurrence and prevalence of KBD, while the relationship between Zn and KBD needs to be further explored in the Tibetan Plateau.

Constraint on selenium bioavailability caused by its geochemical behavior in typical Kaschin–Beck disease areas in Aba, Sichuan Province of China

Kaschin–Beck disease (KBD), an endemic osteoarthropathy, is distributed in the low-selenium (Se)-belt that stretches from northeast to southwest China. However, very few studies have investigated the relationship between low bioavailabitity of Se and KBD. The present study examined the behavior of Se and other elements in areas with varying levels of KBD prevalence using pedological and geochemical methods. Rhizosphere soil samples obtained from the KBD-stricken Aba area were classified into Ustic Isohumisols (J2), Udic Luvisols (L4), Stagnic Gleysols (I2), and Cryic Cambisols (M1) and the integrated constraints on selenium bioavailability in these soils were analyzed. We found that Se concentration in soil profiles from a typical KBD area ranged between 0.08μg·g−1 and 0.215μg·g−1, indicating absent and marginal bioavailability, respectively. This suggested that low Se bioavailability may be a feature that soils inherit from their Se-deficient parent materials. Moreover, the soil types examined showed different geochemical behaviors such as eluviation for soluble Se(VI), migration of Se(IV) for its adsorption on clay and sesquioxide, and extreme redox conditions. In conclusion, a higher level of Se bioavailability in environment might be related to a lower risk of KBD, and our results offer a foundation for scientific theory on ecological geochemistry and improve our understanding of KBD.

T-2 Toxin Contamination in Grains and Selenium Concentration in Drinking Water and Grains in Kaschin–Beck Disease Endemic Areas of Qinghai Province

It has been strongly suggested that two factors are involved in the development of Kaschin-Beck Disease (KBD), namely grains contamination with T-2 toxin and selenium deficiency. So our team undertook a survey about grains and drinking water in three rural KBD endemic villages and one non-KBD village in Qinghai Province. The level of T-2 toxin contamination in 364 grain samples was assayed using an ELISA kit. The selenium concentration in these grains and 15 drinking water samples from three KBD endemic villages were determined using the 2,3-diaminonaphthalene fluorometric assay. The results revealed that the level of T-2 toxin contamination in the samples from three KBD endemic villages was relatively high with an average level of 78.91ng/g in wheat and 47.47ng/g in flour. The T-2 toxin level in samples from the non-KBD village (12.23ng/g) was significantly lower than that of local grains from the three KBD endemic villages. The average selenium content in wheat and flour from KBD areas was 0.0045 and 0.0067μg/g, respectively. The selenium concentration in local grain samples was significantly lower than that in samples from the non-KBD village (0.0604μg/g). In addition, the selenium concentration in drinking water from three KBD endemic villages was also low (0.156μg/L). These results support a potential role of T-2 toxin contamination and selenium deficiency in KBD. Compared with non-KBD endemic areas, health hazards in grains and in the environment of KBD endemic areas were observed.

Erratum to: Environmental selenium in the Kaschin–Beck disease area, Tibetan Plateau, China

The original publication of the article contained mistakes in figure citations. The contents are listed as follows: Page 498, Left column, Under Section: ‘‘Selenium contents in drinking water’’ Fig. 1 citation must be Fig. 2. Page 498, Right column, Under Section: ‘‘Selenium contents in cultivated topsoil’’ Fig. 2 citation must be Fig. 3. Page 499, Left column, Under Section: ‘‘Selenium contents in Highland Barley grains’’ Fig. 3 citation must be Fig. 4. Page 499, Left column, Under Section: ‘‘Selenium contents in tsamba’’ Fig. 4 citation must be Fig. 5. Page 499, Right column, Under Section: ‘‘Selenium in the soil-plant-food system’’ Fig. 5 citation should be deleted/cancelled.

Environmental selenium in the Kaschin–Beck disease area, Tibetan Plateau, China

Now, there is a decreasing trend for the prevalence rate of Kaschin-Beck disease (KBD) in most parts of China, but the disease is still active and severe in the Tibetan Plateau for some reason. To further explore the role of selenium in the occurrence of KBD, We collected samples including drinking water, cultivated topsoil, Highland Barley grains, and tsamba in Rangtang County and Aba County, Sichuan Province and determined concentrations of selenium by Hydride Generation Atomic Fluorescence Spectrometry. Levels of selenium in the environment were analyzed in detail. Selenium in the soil-plant-food system and their relationship with prevalence rate of KBD were also discussed. The results indicate: (a) the levels of environmental selenium are very low and the study area belongs to a selenium-deficient ecological landscape; (b) the KBD becomes much more severe with decreasing environmental selenium under the selenium-deficient condition. Namely, the lower the environmental selenium is, the more severe the disease is; (c) soil selenium deficiency plays a critical role for the prevalence of local KBD, and more factors inducing selenium deficiency should be more concerned in the future.

Investigation on the state of Kaschin-Beck disease in Shanxi province in 2008

Objective To investigate the current situation and variation in the tendency of Kaschin-Beck disease (KBD) in Shanxi province, to assess the effectiveness of prevention measures, and to provide evidence for making scientific and effective tactics in prevention and control of the disease. Methods In 2008, according to National Technical Scheme for Kaschin-Beck Disease Control in 2007, children aged 7 - 12 years underwent clinical and X-ray examination in two historical severe KBD areas of Shanxi province, the observed position on Xray film was finger bone and carpal bone. Adults aged 16 years and above were clinically examined in 50 villages of 13 counties of KBD areas, Shanxi province. The diagnosis was based on Diagnostic Standard of Kashin-Beck Disease(GB 16003-1995), the adult patients were degreed according to the state of illness and divided into different groups according to their ages. Results A total of 181 children were examined, none of them was diagnosed as clinical KBD patient. The positive cases of X-ray were 2, X-ray detectable rate of metaphysis was 1.1% for children.In the 50 villages 13 871 of adults were examined and 801 KBD patients were found and the detectable rate was 5.77%. The detectable rate increased with age. The adult patients distributed mainly in the subpopulation aged 51years and above and these patients accounted for 70.66% (566/801) of total people examined. Degrees Ⅱ and Ⅲ patients at these ages accounted for 71.78%(206/287) of total degrees Ⅱ and Ⅲ patients. Conclusions The state of child KBD in Shanxi is under the national control standards. The detectable rate of adult KBD is higher. Relevant departments should pay close attention to the treatment of adult patients. Key words: Kaschin-Beck disease; Children; Adults; Epidemiologic studies; Outcome assessment

Quantification and Comparison of Soil Elements in the Tibetan Plateau Kaschin-Beck Disease Area

The prevalence rate of Kaschin-Beck disease (KBD) in most parts of China is currently decreasing, but the disease is still active and severe on the Tibetan Plateau. Soil samples including the surface layer (0-20 cm) and the subsurface layer (20-40 cm) in the cultivated and natural soil profiles were collected, and the mechanical composite and total concentration of arsenic, cobalt, copper, iron, mercury, manganese, molybdenum, selenium, and zinc were determined. Concentrations of arsenic, iron, manganese, copper, and selenium in the surface soil were lower than those in the subsurface soil. The same was true of physical clay in the soil profiles. However, there were no significant differences between the different soil layers. The concentrations of selenium, molybdenum, and mercury were somewhat lower compared with the average concentrations of soils in China. Deficiencies of molybdenum and selenium both play a critical role in occurrence of KBD, but whether or not soil mercury at a low level contributes to KBD is still unclear. A correlation analysis of soil elements showed that there is a positive correlation between iron, cobalt, and manganese due to their similar chemical characteristics. Selenium concentrations in soil as well as the physical clay and iron descend with the deterioration of KBD, but mercury concentrations in soil ascend with the aggravation of the disease. The results show that selenium deficiencies greatly influence the disease, and a deficiency of molybdenum is likely another important factor in inducing KBD. Moreover, determining whether low levels of soil mercury contribute to KBD should be investigated in the future.