ABSTRACT
<p><b>OBJECTIVE</b>To detect the spatial distribution characteristics of iodine in drinking water of residents in Shandong province with spatial autocorrelation analysis.</p><p><b>METHODS</b>The county-based study set Shandong province as a research site. A total of 108 164 water samples from 140 counties were collected. The drinking water iodine data in county-level city between 2008 to 2010 were obtained from Shandong Institute of Prevention and Control for Endemic Disease and was merged with an electronic map to build a spatial database. Global and local Moran's I index were calculated, respectively, and spatial autocorrelation and cluster range of iodine distribution in drinking water in Shandong province were studied by SaTScan software.</p><p><b>RESULTS</b>All counties were further grouped according to the "criteria of delimitation for IDD endemic areas" and "determination and classification of the areas of high water iodine and the endemic areas of iodine excess goiter", and 90 counties were iodine deficiency (< 10 µg/L), 31 were iodine suitable (10 - 150 µg/L), and 19 (> 150 µg/L) were high iodine. For the overall study area, the iodine distribution in drinking water in Shandong province existed spatial autocorrelation (Moran's I = 0.52, Z = 7.4, P < 0.01). For the local scale, the drinking water iodine in 18 counties of Dezhou, Liaocheng and Heze city in western Shandong province was clustered, the local Moran's I were between 0.22 - 1.00 (P < 0.01), which were all high-high clusters, indicating the positive spatial correlation. Spatial analysis using SaTScan software detected two cluster areas including 20 counties, which the centers located in Xiajin and Dingtao county, the cluster radiuses were 57.47 km and 65.58 km respectively. The analysis results were consistent with the results of local spatial autocorrelation.</p><p><b>CONCLUSION</b>There are apparent spatial autocorrelation and strong spatial heterogeneity existed in the iodine distribution in drink water in Shandong province.</p>
Subject(s)
China , Cluster Analysis , Drinking Water , Iodine , Spatial Analysis , Statistical DistributionsABSTRACT
ObjectiveTo look into the distribution of “iodine suitable” region in iodine-deficient areas in Shandong province and to provide a scientific basis for guiding the redesignate of iodine-deficient areas and launch scientific supply of iodine.Methods One to 3 copies of water source samples were collected in 105 existing iodine-deficient counties by village.Water iodine content was detected by arsenic-cerium catalytic spectrophotometry.The areas with water iodine content below 10 μg/L was defined as iodine-deficient areas and among 10 - 150 μg/L were “iodine suitable areas” and greater than 150 μg/L were high iodine areas.Results The research was carried out in 14 cities,105 counties,and 1337 towns.We collected 65 716 water samples.Sample recovery efficiency reached 99.8％.The median of water iodine was 5.57 μg/L.In the 1337 towns surveyed,there were 82.05％(1097/1337) of the township with water iodine median ＜ 10 μg/L,17.43％(233/1337) between 10 - 150 μg/L,and 0.52％(7/1337) ＞ 150 μg/L.Conclusions In Shandong province,the water “iodine suitable” regions are distributed scattered with considerable proportion.In iodine-deficient areas,there are areas with high water iodine,and iodine-deficient regions should be redrawn.Emphasis should be put on iodine nutritional status of residents in “high iodine and iodine suitable” regions,and iodine supplementation should be carries out scientifically.
ABSTRACT
Objective To learn the iodine nutritional status of the vulnerable population with different iodine level under the current level of iodized salt in Shandong province and to offer prevention and cure measures.Methods Five groups of vulnerable population including school children aged 8 - 10, pregnant, lactation women, infants and women of childbearing age from mountain areas ( Daiyue, Mengyin counties ) , plain ( Luxian,Gaomi counties ) and coastal (Zhaoyuan county ) of five different iodine deficient areas were investigated in 2007.The thyroids of children aged 8 - 10 were checked by palpation and B ultrasound, their edible salt iodine level was detected by direct titration. The lever of urinary iodine of vulnerable population was examined by arsenic and cerium speetrophotometry. Results The goiter rates of 8 - 10 year-old were 1.8%(9/514) and 1.2%(6/514), respectively by palpation and B-ultrasonic. The mean iodine of 501 edible salt samples was 30.95 mg/kg. The coverage rate of iodized salt was 94.6% (474/501). The rate of qualified iodized salt was 90.4% (453/501). The median of urinary iodine was 216.7 μg,/L. The urinary iodine of school children aged 8 - 10, pregnant, lactation women, infants and women of childbearing age were 234.0, 165.5, 162.4, 257.5, 233.0 μg/L, respectively. Conclusions Current iodine nutritional level is basically appropriate in all groups of vulnerable people. The current iodine content of iodized salt could meet the needs of population from different iodine deficient areas of Shandong province.
ABSTRACT
Objective To look into the current distribution of iodine deficiency area in Shandong province and to guide the re-defined iodine deficiency area and to supplement iodine scientifically. Methods In 2008, 100 iodine deficiency counties(cities, districts), designated in Shandong province's "to supplement iodized salt to eliminate the hazard of iodine deficiency management regulations", were selected in the study. One to three samples were collected from water source which was used by the majority of local residents in the 100 iodine deficiency places and iodine concentration was tested by As3+-Ce4+ catalyzing spectrophotometry. Results A total of 65 716 water samples were collected. Sample recovery efficiency reached 99.8%(65 572/65 716). The median water iodine was 5.57 μg/L, with 82.05%( 1097/1337 ) of the township(town) met criteria for the classification of iodine deficiency areas(water iodine ＜ 10 μg/L), 17.43%(233/1337) of the township (town) water iodine moderate(water iodine 10 - 150 μg/L), and 0.52%(7/1337)of the township(town) should be defined high iodine areas(water iodine ＞ 150 - 300 μg/L). Conclusions The iodine deficiency areas should be redefined because water iodine concentrations of iodine deficiency areas have changed. We suggest that the smallest place to supply salt with different range of iodine content is set to the township(town).
ABSTRACT
Objective To survey the prevalence rates of adult carotid atherosclerosis in water-sourceoriginated high iodine area in Shandong province in 2008 and discuss the relationship between water-sourceoriginated high iodine and carotid atherosclerosis occurrence. Methods Yuncheng county was chosen as observation area which included Dachenlou, Weigai, Liuyi and Ershilipu villages. Juye county was chosen as control that included Zhangxi, Bihainan, Xiaguan and Qiji villages. Two hundred and ninety-nine participants aged over 40 from water-source-originated high iodine areas and 323 residents aged over 40 from normal iodine areas were investigated.Portable-type B mode color Doppler was performed to examine the carotid artery of all participants. The adult carotid atherosclerosis was diagnosed and graded through the ultrasonograms. Results The prevalence rates of adult carotid atherosclerosis in the 4 water-source-originated high iodine villages of Dachenlou, Weigai, Liuyi and Ershilipu were 47.1% (33/70) ,62.2% (51/82) ,67.5% (52/77) and 58.6% (41/70), respectively and the prevalence rates of adult carotid atherosclerosis in the 4 normal iodine villages of Zhangxi, Bihainan, Xiaguan and Qiji were 40.7%(35/86),40.8% (31/76),38.2% (34/89) and 37.5% (27/72), respectively. The prevalence rates of adult carotid atherosclerosis standardized by age in the 4 high iodine villages and the 4 normal iodine villages were 45.81% ,58.18% ,61.63%,55.34% and 34.66%,36.25%,43.01% ,41.30%, respectively. The prevalence rates were higher in high iodine villages than that in control villages(T = 26, P ＜ 0.05 ). There were 136 people scored "0", 120 people scored "1 -3",43 people scored "4 - 7", and total 299 people. There were 201 people scored "0", 87 people scored "1 - 3", 35 people scored "4 - 7", and total 323 people. The expected prevalence rates and severity of adult carotid atherosclerosis was significantly different between high iodine area and normal iodine area (x2 = 17.54,18.42, all P ＜ 0.01).Conclusion The prevalence rate and severity of adult atherosclerosis in water-source-originatod high iodine area is higher than that in normal iodine area.
ABSTRACT
Objective To survey the highly risk iodine deficiency regions of Shandong Province and to provide reference basis for further executing urgent iodine supply. Methods The annual document of cretinism in Licheng District in Jinan City and Shouguang City, the two iodine deficiency regions, were referred. Forty children aged 8-10 years of 2 targeted schools from 3 towns out of every targeted region underwent palpation, ultrasonography and As3+-Ce4+catalyzing speetrophotometry for ultra iodine examination. Twenty women aged 18-40 years from 2 villages sampled from every targeted town received ultra iodine examination and edible salt examination of iodine with direct titration. Results No new cretinism and suspected cretinism was found since 1995 in the regions. The goiter rates of children of the two regions detected with palpation and ultrasonography were 7.5% (18/241),6.2% (15/241) and 5.0% (13/259), 1.2% (3/259), respectively. Two hundred forty and 249 urine samples were respectively collected in school children, in which the median urinary iodine was 226.3,282.7 μg/L. One hundred twenty urine samples were respectively collected from the two group of women, resulting a median urinary iodine of 187.2,321.7 μg/L. Eight and 2 salt samples were free of iodine in 120 salt samples collected each region, respectively. The rate of qualified iodized salt was 100%. Conclusions It is not necessary to urgently implement iodine supply in Shouguang City and Licheng District. However, reinforcement of supervise on salt industry and eliminating the hazard from non-iodized and disqualified iodized salt remains in need.
ABSTRACT
Objective To investigate the danger of iodine excess for people in the downstream area of Yellow River in Shandong Province by describing the distribution of iodine excess water and the gorer of children Methods Water samples were collected from 5 villages of every town of Yuncheng,Jiaxiang and Dongchangfu Counties to determine the iodine of the water using arsenic cerium oxidation reduction method.In the 5 towns having water iodine in the range of 150～300μg/L,200 students aged from 8～10 years received the paJpation of thyroid,half of them were also measured of urinary iodine with As3+-Ce4+ catalytic spectrophotometry using ammonium persulfate digestion method,and 50 of the 100 students further underwent thyroid B-ultrasound.Results Three counties all have high iodine towns.The medium of urinary iodine of 30 town8 in 56 towns was higher than 150μg/L Urinary iodine and sign detection were performed in 13 towns,where water iodine was between 150～ 300μg/L;the medium ofurinary iodine of 11 towns were higherthan 400μg/L,and 3 of the 11 towns were higher than 800μg/L.In all 13 towns,the goiter rate of the students aged 8 to 10 years exceeded 5%by palpation in 11 towns:exceeded 5% by B-ultrasound method in 9 towns.Conclusions There are areas of iodine excess in drinking water and iodine-excess endemic goiter prevails in downstream area of the Yellow River in Shandong Province.It indicates that iodine excess in drinking water has done severe harm in these areas. Active management should be taken to control this endemic disease.
ABSTRACT
Objective To explore the status of iodine nutrition in 8～10 years children after universal salt iodization(USI)in the iodine deficiency area.Methods Probability proportion to size method(PPS)or simple random sampling methods were used to sample children aged 8～10 years in iodine deficiency area in the vear 1995,1997,1999,2002 and 2005, respectively.Goiter were detected by palpation and B-ultrasound, iodine concentration in salt was detected by direct titration method and that in urine by the method of As3+-Ce4+catalytic spectrophotometry.Results After USI has been implemented,the median of salt and urinary iodine tended to mcreaseand the goiter rate tended to decrease year by year.In 2005,the coverage rate of iodinated salt was elevated to 97.2%,qualified iodize salt rate was 97.1%and edible qualified iodinated salt rate was 94.3%in the whole iodine deficiency areas.The median of urinary iodine Was 227.7 μg/L 89.7%(323/360)of the population had a level of the urinary iodine over 100μg/L Goiter rate of 8～10 years children Wag decreased from 22.3%(282/1267)to 4.4%(53/1200) from 1995 to 2005.Conclusion After 10-year USI,the status of iodine nutrition in ShaJldong Province has been promoted obviously and it is in a suitable iodine nutritional status.
ABSTRACT
Objective To find out prevelence of thyroid goiter on school-aged children in excessive iodine region of Shandong Province.Methods By employing B-ultrasonography and palpation method,the thyroid volume were investigated and the thyroid goiter rate were calculated among 6415 children aged 8～10 years old in execssire iodine region.Results By employing B-ultrasonography method.The volumes of thyroid in goiter children aged 8,9,10 years were(5.67±1.49),(6.07±1.24),(7.30±2.01)ml,respectively.The goiter rates were 28.84%(683/2368),20.89%(448/2144),11.82%(225/1903).The volumes of thyroid in non-goiter children aged 8,9,10 years were(3.36±0.67),(3.64±0.77),(4.02±0.94)ml.When the normal value of thyroid volume in 8 and 9 year-groups lowered 0.5 ml,the goiter rate would be changed to 18.20%(430/2368)and 12.92%(277/2144) respectively.The thyroid volumes of boys and girls were(4.20±1.38),(4.18±1.73)ml,respectively.The goiter rates of boys and girls were 21.92%(732/3340)and 20.29%(624/3075)respectively.The rates of goiter detected by palpation in 8,9 and 10 year-groups were 10.05%(238/2368),10.31%(221/2144)and 14.45%(275/1903) respectively.Conclusions Along with the increasing age,the volume of thyroid in children aged 8～10 is increasing in excessive iodine region of Shandong Province.But the goiter rate is decreasing ahmg the increasing age.This phenomena may be caused by improper normal value of thyroid volume.Therefore,the normal value of thyroid volume should be revised urgently.