2001-2009年重庆市碘盐监测结果分析

目的 监测2001-2009年重庆市碘盐质量变化,分析其影响因素.方法 在重庆市,按东、西、南、北、中5个方位进行抽样.在碘盐生产、批发环节,前4个方位各抽2个单位,后1个方位抽1个单位,不足9个单位的,则全部抽样,每个单位每月抽1批9份盐样;在居民户环节,以区(县)为单位,前4个方位各抽2个乡(镇),后1个方位抽1个乡(镇),每个乡(镇)抽2个村,每个村抽20份盐样,用氧化还原法检测含碘量.在碘盐生产、批发环节,计算批质量合格率;在居民户环节,计算碘盐覆盖率和合格碘盐食用率.用趋势检验、方差分析和X2检验对数据进行统计学分析.结果 2001-2009年,碘盐生产批质量合格率2001年为92.9%(13/14),其余各年均为100.0%;批发批质量合格率为88.7%(282/318)～99.8%(431/432),其中,2001和2002年均明显低于2003-2009年(X2值范围为4.98～45.69,P均<0.05或<0.01),2003年明显低于2004和2006-2009年(X2值范围为5.19～12.13,P均<0.05或<0.01).居民碘盐覆盖率和合格碘盐食用率分别为94.2%(11 154/11 841)～98.9%(14 061/14 217)和83.5%(9 887/11 841)～95.8%(13 449/14 039),均呈上升趋势(F值分别为9.27、26.39,P均<0.05),合格碘盐食用率达90%以上的区(县)数量逐年增加.盐碘均数生产环节为29.71～36.25 mg/kg,批发环节为31.26～36.13 mg/kg,均呈逐年下降趋势(F值分别为35.45、140.59,P均<0.01);居民户环节盐碘均数为28.84～30.98 mg/kg,较为稳定(F=3.05,P>0.05).各年从生产、批发至居民户盐碘均显著下降(F值范围为38.46～671.23,P均<0.01).结论 重庆市碘盐质量和居民碘盐覆盖率、合格碘盐食用率不断提高.碘盐生产企业未严格按照标准加碘和加碘均匀度差是影响盐碘的因素.

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< 0.05 or < 0.01). The coverage rate and taking rate of qualified iodized salt in residents were 94.2% (11 154/11 841 ) - 98.9% ( 14 061/14 217), 83.5% (9 887/11 841 ) -95.8% (13 449/14 039), respectively. The rates showed an increasing tendency (F = 9.27, 26.39, all P < 0.05).The districts(counties) with qualified iodized salt consumption rate > 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 < 0.01 ). The mean iodine level from the inhabitants were 28.84 - 30.98 mg/kg which remained stable (F = 3.05, 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.

Analysis of iodized salt monitoring results in Chongqing Municipality from 2001 to 2009

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< 0.05 or < 0.01). The coverage rate and taking rate of qualified iodized salt in residents were 94.2% (11 154/11 841 ) - 98.9% ( 14 061/14 217), 83.5% (9 887/11 841 ) -95.8% (13 449/14 039), respectively. The rates showed an increasing tendency (F = 9.27, 26.39, all P < 0.05).The districts(counties) with qualified iodized salt consumption rate > 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 < 0.01 ). The mean iodine level from the inhabitants were 28.84 - 30.98 mg/kg which remained stable (F = 3.05, 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.