Analysis of general survey results of iodine content in drinking water of Shanxi Province

Abstract

Objective To understand the distribution of water iodine in the external environment of Shanxi Province, and to provide a basis for redefining and implementation of scientific iodine supplementation in iodine deficiency, iodine adequate or iodine high areas. Methods In 2012-2016, administrative villages (neighborhood committees) in 119 counties (cities, districts) in 11 cities of Shanxi Province were selected as the investigation units, and 1 to 5 drinking water samples were collected. Water iodine content was detected using arsenic-cerium catalytic spectrophotometry. Areas standard was designated: water iodine content 100 μg/L as iodine high areas. Results A total of 26 213 administrative villages (neighborhood committees) of 1 362 townships (towns) of 119 counties (cities, districts) were surveyed, covering 2 850.94 ten thousand people. A total of 32 766 water samples were collected and the median iodine was 5.2 μg/L. There were 18 199 villages with water iodine < 10 μg/L, accounting for 69.4% (covering 1 812.17 ten thousand people, accounting for 63.6%), 6 471 villages with water iodine 10-< 50 μg/L, accounting for 24.7% (covering 787.44 ten thousand people, accounting for 27.6%), 1 166 villages with water iodine 50-< 100 μg/L, accounting for 4.4% (covering 181.46 ten thousand people, accounting for 6.4%), 377 villages with water iodine ≥100 μg/L, accounting for 1.4% (covering 69.87 ten thousand people, accounting for 2.5%). In 1 362 townships (towns), 71.1% (969) water iodine median was < 10 μg/L, 24.2% (330) water iodine median was in 10-< 50 μg/L, 3.4% (46) water iodine median was in 50-< 100 μg/L, and 1.2% (17) water iodine median was ≥100 μg/L. In 119 counties (cities, districts), there were 90 counties(accounting for 75.6%) with the water median < 10 μg/L, there were 26 counties (accounting for 21.8%) with the water median 10-< 50 μg/L. Conclusions Most parts of Shanxi Province (or the resident population) are iodine deficiency areas, the external environment water iodine contents in the rest of the regions are different, we should adopt different iodine supplement or iodine reduction measures in regions with different water iodine levels. Key words: Drinking water; Iodine; Census; Administrative villages