Objective To find out the distribution of drinking-tea-borne fluorosis in the six ethnics in Qinghai Province, and to provide basic data for prevention and control of the disease. Methods In 2010, according to the requirement of “The National Surveillance Program of Drinking-Tea-borne Fluorosis”, six ethnics accounted for 99.59% of total population in Qinghai Province were investigated in 28 counties having brick-tea drinking habit. Three townships and a town in each county, two administrative villages(residents’ committee) in each township and town were chosen and 50 adults in each administrative village and residents ’ committee were selected to check skeletal fluorosis, dental fluorosis, urine fluoride and daily drinking amount of tea water. Five to six samples of drinking tea water were determined. Dental fluorosis was examined by Deans method; the fluoride content of brick-tea and urine were determined by fluoride ion selective electrode; the skeletal fluorosis was diagnosed based on “Endemic Osteofluorosis Clinical Indexing Diagnosis Standard”( WS 192-2008 ) . Results A total of 10 335 adults were surveyed, the number of Tibetan, Han, Hui, Mongolian, Tu and Salar ethnics were 4 972, 3 063, 1 196, 634, 235 and 235, respectively. The daily drinking amounts of tea water in Mongolian, Tibetan, Hui, Tu, Han and Salar ethnics were 2.53, 2.19, 1.74, 1.63, 1.22 and 1.07 L, respectively. Daily fluoride intakes in Tibetan, Mongolian, Tu, Hui, Han and Salar ethnics were 3.99, 2.78,2.27, 2.16, 1.78 and 1.28 mg, respectively. The medians of urinary fluoride concentration of the Tibetan, Tu, Hui, Han, Mongolian and Salar ethnics were 1.46, 1.19, 1.12, 0.98, 0.93 and 0.81 mg/L, respectively. The prevalence rates of dental fluorosis of the Hui, Han, Tibetan, Tu, Mongolian and Salar ethnics were 34.53%(413/1 196), 27.07%(829/3 063), 21.60%(1 074/4 972), 20.00%(47/235), 17.98%(114/634) and 6.38%(15/235), respectively. The incidence rates of clinical skeletal fluorosis of the Tibetan, Mongolian, Han, Hui, Tu and Salar ethnics were 13.42%(667/4 972), 11.04%(70/634), 9.31%(285/3 063), 7.61%(91/1 196), 5.53%(13/235) and 4.26%(10/235), respectively. Conclusions The distribution and prevalent status of drinking-tea-borne fluorosis in the six ethnics of Qinghai Province are different. Tibetan and Mongolian ethnics are the key population concerning the prevention and control of the disease.

Objective:To understand the situation of drinking water-borne endemic fluorosis (short for drinking water fluorosis) in Huangzhong, Ping'an and Ledu districts of Qinghai Province and operation status of water improvement projects, and to evaluate the effect of control measures.Methods:In historical drinking water fluorosis villages of Huangzhong, Ping'an and Ledu districts of Qinghai Province in 2018, the status of water improvement, the operation of water improvement projects and the content of water fluoride were investigated; the dental fluorosis of 8-12 years old children in all investigated villages was checked; 3 villages from 3 districts were selected, X-ray examination for skeletal fluorosis and urinary fluoride detection of adults over 25 years old of age were performed.Results:Eight-two historical drinking water fluorosis villages in 3 districts were investigated and all the villages had water improvement projects, in addition, the water improvement projects were operating normally, and the water fluoride content ranged from 0.10 to 0.37 mg/L, which were in line with the drinking water fluoride content standard (< 1.2 mg/L). Totally 2 503 children aged 8-12 years old were examined, the detection rate of dental fluorosis was 6.03% (151/2 503), the index of dental fluorosis was 0.13, the epidemic intensity was negative; the detection rates of dental fluorosis in 3 districts were 6.24% (129/2 068), 4.05% (7/173), 5.73% (15/262), respectively, reaching the control standard (< 30%), and the detection rate of dental fluorosis in 81 villages was less than 30%; 198 adults over 25 years old were examined, the detection rate of skeletal fluorosis was 5.05% (10/198), the geometric mean of urinary fluoride was 0.81 mg/L, and skeletal fluorosis cases were mainly in the age group over 40 years old, all of them were mild cases.Conclusions:The fluoride content in drinking water and the detection rate of children's dental fluorosis are all up to the control standard, and the condition of skeletal fluorosis is significantly reduced after the implementation of water improvement measures in Huangzhong, Ping'an and Ledu districts. It can be seen that the prevention and control of drinking water fluorosis in Huangzhong, Ping'an and Ledu districts have achieved good results, but later management and condition monitoring of water improvement projects should be strengthened to prevent the disease from rebounding.

Objective:To investigate the dietary iodine intake of people in different areas of Qinghai Province, and to provide the basis for scientific iodine supplementation and continuous elimination of iodine deficiency hazards.Methods:From 2018 to 2019, according to administrative division, natural geographical regions, population distribution and economic development level of Qinghai Province, a total of 14 survey sites were selected. One village was selected from each survey site, and 20 households were selected from each village, the salt samples and 24 h urine samples of all family members were collected to detect salt iodine and urinary iodine. One drinking water sample was collected at the five directions of east, west, south, north and middle of each village to detect water iodine. Salt iodine was detected by direct titration, urinary iodine and water iodine were detected by arsenic-cerium catalytic spectrophotometry. At the same time, the 3-day weighing method was used to investigate the diet, the daily dietary iodine intake per capita (the result was expressed as average) and the proportion of dietary iodine in urinary iodine were calculated, the daily dietary iodine intake per capita of different production modes (agricultural region and pastoral region), different geographical environment (Hehuang Valley, Qaidam Basin, Qilian Mountain and Qingnan Plateau), different nationalities (Han, Tibetan, Hui, Mongolian, Tu, Salar) and different economic levels (< 8 000, 8 000 -, 10 000 -, ≥12 000 Yuan) were compared.Results:A total of 999 people from 280 families were surveyed, including 511 males and 488 females. The median water iodine of each survey site was less than 10 μg/L, all of which were environmentally iodine-deficient areas. A total of 280 salt samples were collected, the median salt iodine was 26.0 mg/kg, and the consumption rate of qualified iodized salt was 100% (280/280). A total of 999 urine samples were tested, and the median urinary iodine of people was 192.5 μg/L, which was at an appropriate level of iodine. There was no statistically significant difference ( t =-1.599, P > 0.05) in the daily dietary iodine intake per capita (28.53, 33.44 μg) of people in agricultural region ( n = 643) and pastoral region ( n = 356). The daily dietary iodine intake per capita (25.38, 33.30, 32.98, 34.79 μg) of people in Hehuang Valley ( n = 448), Qaidam Basin ( n = 125), Qilian Mountain ( n = 157), and Qingnan Plateau ( n = 269) were compared, the difference was statistically significant ( F = 2.883, P < 0.05); among them, the daily dietary iodine intake per capita in Hehuang Valley was lower than that in Qingnan Plateau ( P < 0.05). The daily dietary iodine intake per capita of different nationalities were compared, the difference was statistically significant ( F = 3.647, P < 0.05), Salar ( n = 68) and Tibetan ( n = 239) were higher (37.21 and 32.21 μg). The daily dietary iodine intake per capita (38.97, 17.01, 30.86, 33.14 μg) of annual per capita disposable income < 8 000 ( n = 194), 8 000-( n = 221), 10 000-( n = 302), ≥12 000 Yuan ( n = 282) were compared, the difference was statistically significant ( F = 9.407, P < 0.05). The proportions of dietary iodine in urinary iodine of various population ranged from 5.35% to 15.54%. Conclusions:The iodine nutrition of people in Qinghai Province is suitable, the dietary iodine intake of people is closely related to geographical environment, nationality and economic level. But the proportion of dietary iodine in urinary iodine is relatively low, the consumption of iodized salt is still the main way for people to intake iodine, and it is also the main measure to continuously eliminate the harm of iodine deficiency in Qinghai Province.

Objective To observe the illness change trend of drinking water type endemic arsenic poisoning in Qinghai Province, comprehensively evaluate the effect of prevention and control measures, in order to provide a scientific basis for timely adjustment of the prevention and control measures. Methods From 2010 to 2013, according to the Drinking Water Type Endemic Arsenic Poisoning Monitoring Programs, 3 villages in 2 counties within Qinghai Province were randomly selected as monitoring sites. The arsenic content in drinking water of residents was measured, water improvement projects in all monitoring villages were investigated; at the same time an investigation of arsenic disease in resident population was conducted, and urinary arsenic content was monitored. Arsenic in drinking water and urine was determined by hydride generation atomic fluorescence spectrometry, and arsenic poisoning was diagnosed using Endemic Arsenic Poisoning Diagnostic Criteria (WS/T 211-2001). Results Of the three water improvement projects, two were water arsenic exceeded the standard, and one was intermittently operated. From 2010 to 2013, the arsenic poisoning detec tion rate in Baoning Village was 27.30% (193/707), 31.90%(245/768), 29.35%(221/753) and 28.22%(219/776); in Kecai Village was 32.62%(107/328), 34.83%(124/356), 31.26%(131/419) and 29.35%(118/402);and in Manimotai Village was 56.58%(43/76), 52.81%(47/89), 45.10%(46/102) and 34.69% (34/98), there was no significant difference statistically of the arsenic poisoning detection rates in the three monitored villages in the 4 years (χ2 =3.09, 0.04, 0.92, all P>0.05). From 2010 to 2013, women arsenic poisoning detection rate was 36.45%(203/557), 40.59%(246/606), 36.12%(225/623) and 34.77%(218/627), respectively;men was 25.27%(140/554), 28.01%(170/607), 26.57%(173/651) and 23.57%(153/649), respectively;women arsenic poisoning detection rates were higher than those of men (χ2 = 16.25, 21.32, 13.49, 19.38, all P < 0.05). Arsenic poisoning detection rate of people younger than 60 years old had a tendency to increase with age. In 2012 and 2013, 105 and 93 urine samples were tested, respectively; urinary arsenic geometric mean was 0.113 and 0.149 mg/L. Conclusions Water improvement projects and water quality are not optimistic, and prevalence of arsenic poisoning is still at a higher level. A sound long-term monitoring program should be established as soon as possible, the management and maintenance of water improvement projects should be strengthened, and the monitoring and prevention work should not be neglected.

Objective To understand the pathway of iodine intaking among Tibetan, and provide basic data for prevention and control of iodine deficiency disorders (IDD). Methods Through the method of random sampling, the boarding and day student aged 8 - 10 and women of childbearing age were conducted dietary survey to understand the condition of food intaking via the 24 h review method in 2015. Samples of urine, drinking water, dried beef, milk, Qula and fried noodles were collected and tested iodine level. Results Due to taking iodized salt three times a day with meals, the median of urinary iodine among 492 investigated boarding students was 179.2 μg/L;differently, the median of urinary iodine among 298 day students in this investigation was 79.6 μg/L who taking iodized salt only at lunch at school;and in the study, the median of urinary iodine among 158 women of childbearing age who took iodine-free salt daily was 33.7 μg/L. The iodine contents in 51 drinking water samples, 66 dried beef samples, 48 milk samples, 20 Qula samples and 37 fried noodle samples were quantified respectively, and the average iodine contents of each food were 0.8 μg/L in drinking water, 59.1 μg/kg in dried beef, 61.5 μg/kg in milk, 226.4 μg/kg in Qula and 17.0 μg/kg in fried noodles. The acceptable daily intake (ADI) of iodine of the boarding and day students aged from 8 to 10 and women of child bearing age were 234.0, 126.4 and 76.7 μg/d, respectively, among which the ADI of iodine with iodized salt were 208.0, 78.0 and 0.0 μg/d. Conclusion Consuming iodized salt is a main method to get iodine among Tibetans in Nangqian County, so that it is significant to carried out this measure for a long time for free to let them have iodized salt every day instead of iodine-free one.

Objective To understand the current environmental selenium and T-2 toxin levels in the critically ill areas of Kaschin-Beck disease in Qinghai Province.Methods In three historical villages with serious diseases of Kaschin-Beck disease,Xia,Xiemalang and Yaoshidao were selected;at the same time,three villages from non-diseased areas were selected as control villages including Damitan,Gongba and Deang in 2018.Six villages were used as survey sites.Collected hair samples of children aged 6-12 years old,to measure the hair selenium content in Xinghai and Guide survey sites [children's selenium content reference value was (0.60 ± 0.03)mg/kg].Ten samples of self-produced grain were collected from each survey site,selenium content [wheat selenium content reference value was (0.053 ± 0.007) mg/kg] and T-2 toxin content in grain was detected in the six survey sites.Ten soil samples were collected from each survey sites.Soil selenium content was detected in the six survey sites [soil selenium content reference value was (0.24 ± 0.03) mg/kg].Results The selenium contents of children's hair in the diseased and non-diseased areas of Xinghai County,Guide County were (0.252 ± 0.071),(0.296 ± 0.087);(0.225 ± 0.032),(0.238 ± 0.040) mg/kg,respectively.The selenium contents of wheat in the diseased and nondiseased areas of the three counties were 0.000 19,0.003 66;0.000 15,0.004 16;0.016 78,0.016 94 mg/kg.The soil selenium contents in the diseased and non-diseased areas of the three counties were (0.095 ± 0.015),(0.114 ± 0.014);(0.082 ± 0.013),(0.083 ± 0.018);(0.080 ± 0.005),(0.060 ± 0.013) mg/kg.The T-2 toxin contents of wheat in the diseased and non-diseased areas of the three counties were (3.173 ± 0.762),(3.100 ± 0.473);(2.506 ± 0.430),(3.186 ± 0.451);(2.416 ± 0.619),(2.879 ± 0.456) μg/kg.Conclusions The content of hair selenium of children is close to the normal reference value in the area of Kaschin-Beck disease in Qinghai Province.The contents of soil selenium and the main grain selenium of the residents are low in the diseased village.A certain amount of T-2 toxin is detected in the main grain of residential households.

Objective:To study the epidemic status of drinking brick-tea type fluorosis in Haibei Prefecture, Qinghai Province, and to provide evidence for future targeted intervention measures.Methods:In 2018, according to the historical prevalence of drinking brick-tea type fluorosis in Haibei Prefecture, in Haiyan, Menyuan, Qilian, Gangcha counties, based on the classification of pastoral area, agricultural area, semi-agricultural and semi-pastoral areas, one township (town) was selected, and one natural village was selected in each township (town) as a survey site. Drinking water samples of local residents were collected, water fluorine content was detected; and 10 households in Haiyan and Menyuan counties were selected, respectively, 100 brick-tea samples of different brands were collected, brick-tea fluorine content was detected. At the same time, dental fluorosis was examined in all children aged 8 to 12 years old in survey sites; and X-ray of skeletal fluorosis was examined in all adults aged 26 - 55 years old in Haiyan and Menyuan counties, urine samples were collected from adults at random for 1 time and urine fluorine content was detected. Water fluorine, brick-tea fluorine, and urine fluorine contents were detected by ion selective electrode method; the diagnosis of dental fluorosis was based on "Diagnosis of Dental Fluorosis" (WS/T 208-2011), and the diagnosis of skeletal fluorosis was based on "Diagnostic Criteria for Endemic Skeletal Fluorosis" (WS 192-2008).Results:The mean of fluorine of the 10 water samples was 0.33 mg/L (0.20 - 0.84 mg/L). The mean of fluorine of the 100 brick-tea samples was 750 mg/kg (230 - 1 660 mg/kg), and the mean of daily fluorine intake from brick-tea of each person was 1.87 mg. The detection rate of dental fluorosis in children was 22.56% (217/962), and the dental fluorosis index was 0.42. The detection rate of skeletal fluorosis in adults was 6.88% (24/349); and the geometric mean of urine fluorine was 1.53 mg/L (0.20 - 20.60 mg/L).Conclusion:In Haibei Prefecture, residents are still affected by drinking brick-tea type fluorosis, which needs to be paid attention to.

Objective:To investigate the effects of 3 treatment methods on serum cytokines in Kaschin-Beck disease (KBD) patients.Methods:In May 2015, according to "Diagnosis of Kaschin-Beck disease" (WS/T 207-2010), KBD patients with grade Ⅰ and above who lived in KBD areas of Guide, Xinghai and Banma counties of Qinghai Province for at least 25 years and aged 25 - 62 years old were selected as research subjects. Patients were divided into 3 groups according to different treatment methods. The first group ( n = 91) was treated with Celecoxib + Xiaohuoluo pill (concentrated pill), the second group ( n = 89) was treated with Celecoxib + bone-strengthening joint pill, and the third group ( n = 94) was treated with Celecoxib + anti-osteogenic tablet, and the overall treatment effects of 6 months after treatment of the 3 groups were compared and analyzed. The contents of serum nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β) and hyaluronic acid (HA) in patients before and after treatment were detected by enzyme-linked immunosorbent assay (ELISA). Results:A total of 274 KBD patients were included, aged (47.24 ± 18.97) years old, including 132 males and 142 females. The treatment effective rates in the first, second and third groups were 80.22% (73/91), 77.53% (69/89) and 77.66% (73/94), respectively, and there was no significant difference between the three groups (χ 2 = 0.25, P > 0.05). Before and after the treatment, the serum NO contents of the 3 groups [(149.23 ± 20.61), (135.88 ± 29.63), (151.33 ± 22.15), (137.55 ± 31.51), (148.58 ± 24.36), (134.81 ± 28.53) μmol/L] were significantly different ( t = 2.678, 2.403, 3.195, P < 0.05), and there were no significant differences in TNF-α, IL-1β, and HA contents ( P > 0.05). Conclusion:Three treatment methods for treating KBD have achieved certain effects, all the 3 treatment methods have reduced serum NO content and have no significant effect on TNF-α, IL-1β and HA contents.

Objective:To analyze the assessment results of the external quality control in iodine deficiency disorders laboratories at all levels in Qinghai Province so as to provide quality assurance for monitoring and control effect evaluation of iodine deficiency disorders.Methods:The results of urinary iodine, salt iodine, and water iodine quality control assessments at the provincial, city (state) and county-level iodine deficiency disorders laboratories were analyzed in Qinghai Province from 2013 to 2018 (sourced from the annual evaluation results issued by National Reference Laboratory for Iodine Deficiency Disorders). Among them, there were 1 provincial, 8 city (state) and 43 county-level (2017, 2018) laboratories participated in the urinary iodine assessment; 1 provincial, 8 city (state) and 30 county-level (43 in 2017 and 2018) laboratories participated in the salt iodine assessment; 1 provincial and 8 city (state)-level laboratories participated in the water iodine assessment.Results:From 2013 to 2018, the feedback rates and qualified rates of provincial and city (state)-level laboratories participated in the urinary iodine external quality control assessment were 100.0%; the feedback rates of 43 county-level laboratories (2017 and 2018) were 100.0%, and the qualified rates were 93.0%(40/43) and 88.4%(38/43), respectively. The feedback rates and qualified rates for salt iodine assessment in provincial and city (state)-level laboratories were 100.0%; the county-level laboratories feedback rates were 100.0%, and the qualified rates were > 90.0% except for 2014. And the feedback rates of provincial and city (state)-level laboratories for water iodine assessment were 100.0%; the qualified rate of provincial-level laboratory was 100.0%, and the city (state)-level laboratories were 100.0% except 2016 (7/8).Conclusions:The quality control network of Qinghai Province's iodine deficiency disorders laboratories has fully covered all city (state) and county-level laboratories. Provincial, city (state)-level laboratories have stable and reliable levels of urinary iodine, salt iodine, and water iodine; some individual county-level laboratories testing capabilities still need to be improved.

Objective:To systematically evaluate the changes of serum nitric oxide (NO) content in adult patients with Kaschin-Beck disease (KBD).Methods:Systematic retrieval was conducted on China National Knowledge Infrastructure (CNKI), WanFang Data, VIP Database, PubMed, Embase and other databases, to analyze the literatures published from the database establishment to March 31, 2019, on the changes of serum NO content of adult patients with KBD. Meta-analysis was performed using Revman 5.3 software, and mean difference ( MD) and 95% confidence interval ( CI) were calculated; sensitivity analysis was performed using fixed-effect model or random-effect model based on heterogeneity results; and publication bias was evaluated using funnel chart. Results:Totally 7 qualified literatures were included, including 358 cases in the adult KBD group and 305 cases in the control group. After the heterogeneity test, there was heterogeneity among the literatures (χ 2 = 188.07, I2 = 97%, P < 0.01), so a random-effect model was used for Meta-analysis. The NO content in the KBD group was significantly higher than that in the control group (MD = 44.29, 95% CI: 30.57 - 58.00), the difference was statistically significant ( Z = 6.33, P < 0.01). Sensitivity analysis showed that the results of this study were stable. The two sides of the funnel were basically symmetrical, suggesting that the possibility of publication bias was small. Conclusion:The serum level of NO content in adult patients with KBD is significantly increased.