The influence study of new iodine salt standard on salt iodine concentration and urine iodine level in Tangshan city

Objective To understand the variation of salt iodine content and urine iodine concentration after the new standard of iodine content of edible salt in Tangshan city,in order to provide a scientific basis for the relevant policy to iodine deficiency disorders. Methods According to the requirements of National iodine deficiency disorders monitoring project( trial),and Iodine deficiency monitoring implementing project( trial),salt samples were collected from edible salt manufacturers,wholesalers and household from 2011 to 2013,salt samples were tested with direct titration method. 100 children aged 8 to 10 years were randomly sampled from2 counties,using arsenic cerium catalytic spectrophotometry to determine the urine iodine content,to check the rate of goiter; and urinary iodine content of 50 women of child-bearing age 18 to 40 years old were detected. To observe salt iodine concentration and urine iodine concentration before and after the new standard implementation. Results The values of salt iodine concentrations in edible salt of manufacturer and wholesalers in2012 and 2013 were( 26. 16 ± 6. 43) mg / kg,( 25. 44 ± 3. 95 mg) / kg,( 25. 67 ± 5. 81) mg / kg and( 25. 25± 3. 36) mg / kg that were all significantly declined compared with 2011 of( 29. 94 ± 3. 31) mg / kg and( 29. 97 ± 4. 08) mg /Kg,the differences were statistically significant( P 0. 05). The medians of household salt iodine concentration in 2012 was 26. 70 mg / kg,reduced from 28. 60 mg / kg in 2011,but there is no significant statistically differences and 24. 53 mg / kg in 2013 which was reduced further,and there was significant statistically differences( P 0. 05). Compared monitoring results of 2013 with that of 2011,children's urine iodine concentration decline significantly from 252. 52μg / L to 220. 81 μg / L,urinary iodine concentrations of women decline significantly from 260. 13μg / L to 193. 34μg / L( P 0. 05). Conclusions The iodine content of edible salt of Tangshan city meet the standard of GB 26878-2011,which result in urine iodine concentration gradual declined,to an appropriate level.