100 likes | 535 Views
Methods to Analyze Iodine in Salt Moldova – April 2004 - Arnold Timmer UNICEF Regional Office. Methods . Titration Rapid Test kit Iodine Checker Machine . Titration. Quantitative Accurate and reliable Inexpensive
E N D
Methods to Analyze Iodine in SaltMoldova – April 2004 -Arnold TimmerUNICEF Regional Office
Methods • Titration • Rapid Test kit • Iodine Checker Machine
Titration • Quantitative • Accurate and reliable • Inexpensive • Suitable for fixed labs and trained staff in salt companies, external quality control, nutrition/public health center
Rapid Test Kit • Qualitative: yes or no • Inexpensive • Easy to perform by untrained staff • Suitable for small salt producers, salt importers, children at school, household surveys • Not good for quality assurance
Iodine Checker • Measuring iodine in salt quickly and precisely during it production and distribution can be difficult • Titration methods accurate but are not easily applied in salt plants • The Salt Research Institute of the China National Salt Industry Corporation developed the WYD Iodine Checker
Iodine Checker Machine • Measurement range 10-80 mg/kg • Method: • Fixed amount of iodized salt (1 g) is dissolved in distilled water, then H2SO4 (sulfuric acid) and KI (potassium iodide) are added. • iodine reacts with starch to produce a blue color • Works on 220 V or batteries • Cost 300 US$
Independent testing: • Chemical Engineering, Univ. Toronto, Canada • results agreed closely with titration • acceptable accuracy, precision, and reproducibility • China National IDD Reference Laboratory • assessed in 100 labs in salt plants • precision slightly lower than that of titration • batch variance coefficient 5% • practical to use • user-friendly