Effects of different iodine concentration in drinking water on iodine nutrition, thyroid function and volume
10.3760/cma.j.issn.2095-4255.2014.05.019
- VernacularTitle:不同含量水碘对特殊人群碘营养、甲状腺功能和容积的影响
- Author:
Qingzhen JIA
;
Xiangdong ZHANG
;
Yanting REN
;
Baisuo GUO
;
Yongping WANG
- Publication Type:Journal Article
- Keywords:
Iodine;
Excess;
Nutrition,Goiter;
Thyroid function
- From:
Chinese Journal of Endemiology
2014;33(5):540-544
- CountryChina
- Language:Chinese
-
Abstract:
Objective Toinvestigate iodine nutrition,thyroid volume and function of children and women in high water iodine areas,and to discuss the cut-off point of water iodine level where should be defined as iodine excessive areas.Methods In iodine excessive townships in Xiaodian and Qingxu Counties of Taiyuan City,all villages were divided to 4 groups according to the concentration of iodine in drinking water:50 ～ ＜ 100 μg/L (Group A),100 ～ ＜ 150 μg/L(Group B),150 ～ ＜ 300 μg/L(Group C) and ≥300 μg/L(Group D),and 2-3 villages were randomly selected from each group as investigation sites.Two hundred children aged 8-10 and 60 women (20 pregnant women,20 breasffeeding women and 20 women of childbearing age,respectively) were sampled.Drinking water,edible salt and once random urine samples for each studying object were collected,and the iodine content was measured.The goiter volume of children aged 8-10 and triiodothyronine (FT3),free thyroxine (FT4),thyroid stimulating hormone (TSH) of women were determined.Results Totally 708 children and 236 women were selected as respondents who ate non-iodized salt.Iodine content in drinking water of children in groups A,B,C and D was 73.8,144.7,258.5 and 501.0 μg/L,respectively,and that of women was 73.8,144.7,242.7 and 485.9 μg/L,respectively.Median urinary iodine of children in groups A,B,C and D was 274.3,312.8,455.6 and 793.5 μg/L,respectively,and that of women was 238.3,235.2,371.6 and 641.6 μg/L,respectively.The median urinary iodine of children and women increased with increasing water content of iodine.The goiter rate of children was 5.6％ (11/196),13.2％ (25/189),12.6％ (20/158) and 10.9％ (18/165) for each group,respectively,which also increased with increasing water content of iodine.In groups A,C and D,the FT3 and FT4 levels[pmol/L:(3.70 ± 0.59),(14.01 ± 2.44); (3.43 ± 0.57),(12.87 ± 2.12); (3.42 ± 0.47),(12.66 ±1.78)] in pregnant woman were lower than those in breasffeeding women[pmol/L:(4.26 ± ±0.57),(14.73 ± 2.36;(4.28 ± 0.40),(14.77 ± 1.19); (4.36 ± 0.65),(15.66 ± 2.84)] and women of childbearing age[pmol/L:(4.80 ±0.50),(17.47 ± 2.11); (4.21 ± 0.48),(15.83 ± 1.64); (4.26 ± 0.52),(15.53 ± 1.81)].With increasing water content of iodine,FT4 level was decreasing and TSH level was increasing gradually in women.Conclusions When water iodine exceeds 100 μg/L,goiter rate of children has increased significantly.Iodine excessive women and children have appeared one after another with increasing water content of iodine.Women incidence of subclinical hypothyroidism risk has increased with increasing water content of iodine,and the detection rate of subclinical hypothyroidism is significantly higher when water iodine is higher than 300 μg/L.The cut-off point of iodine excessive areas should be descend from 150 μg/L to 100 μg/L.
