Analysis of iodized salt monitoring results in Chongqing Municipality from 2001 to 2009 / 中国地方病学杂志

ABSTRACT

Objective To monitor the quality changes of iodized salt and analyze its impact factor in Chongqing between 2001 and 2009. Methods Salt samples were collected according to the east, west, south,north and center locations in iodized salt production, wholesale and household sectors. Two units in iodized salt production and wholesale segment were sampled from north, south, east and west places and only 1 unit was sampled from the central place. Nine samples were collected every month in each place. If the place had less than 9 units, and then taken all the units. About resident household, 2 townships were sampled from north, south, east and west places, and 1 township was sampled from the central place, then 20 samples were collected from each township. Iodine content was detected by oxidation-reduction assay. The index of mean iodine, qualified rate from factories and wholesale, coverage rate and taking rate of qualified iodized salt in residents were calculated.Significance was analyzed by trend test, analysis of variance and X2 test. Results The qualified rate of iodized salt from the manufacturers was 92.9%(13/14) in 2001 and the rate was 100.0% each year from 2002 to 2009. The qualified rates of iodized salt from the wholesale were 88.7%(282/318) - 99.8%(431/432). The rates of 2001 and 2002 were lower than that of other years(X2 = 4.98 - 45.69, all P 90% kept increasing. The mean iodine from the manufacturers and wholesale were 29.71 - 36.25, and 31.26 - 36.13 mg/kg, respectively. The iodine level showed a descending trend(F = 35.45, 140.59, all P 0.05 ). The iodine level from manufacturers, wholesale to inhabitants showed an descending trend(F = 38.46 - 671.23, all P < 0.01 ). Conclusions The surveillance results of iodized salt shows an increasing tendency in quality of iodized salt, eoverage rate and taking rate of qualified iodized salt. Factors that affect the quality of iodized salt is that the enterprise does not add iodine to salt strictly by the standard.