Iodine is an essential micronutrient with an average

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1 Urinary Iodine Excretion in Urine Samples Among Children in Dahod District, Gujarat JR Damor*, NG Padhiyar**, GL Ninama Abstract Aim: To measure urinary iodine excretion level and to assess the iodine level in salt sample. Study design: Cross-sectional study done in 30 randomly selected wards/villages of Dahod district. Materials and method: The IDD survey at the Dahod district was conducted by population proportionate to size (PPS) cluster sampling. A sample of 90 children (45 boys and 45 girls) of age group of 6-12 years from the school was taken. In each cluster, seven urine samples of boys and seven samples of girls were collected and sent to the public health laboratories. From each cluster, salt samples were collected from a minimum of 10 houses and tested with the use of spot salt testing kit for the presence of iodine. Results: The median urinary iodine level was 115 μg/dl. Age-wise distribution of urinary iodine showed that the proportion of children with urinary iodine excretion <100 μg/dl was lowest in the 6-year age group, whereas the highest proportion was in the 10-year age group. Out of 300 salt samples, 207 samples (69%) had >15 ppm (parts per million) iodine; four samples (1.3%) had <15 ppm iodine. This means that the use of iodized salt was 70.3%. Conclusion: The lowest urinary iodine excretion was seen in age group of six years whereas highest urinary iodine excretion was seen in age group of 10 years. In 69%, salt samples had >15 ppm iodine present and in 1.3%, samples had <15 ppm iodine present. Thirty percent of salt samples were noniodized. Keywords: Iodine deficiency disorders, salt samples, urinary iodine excretion Iodine is an essential micronutrient with an average daily requirement of µg for normal human growth and mental development. Inadequate or poor intake of iodine can result in physical and mental retardation. It affects people of all ages, both sexes and of different socioeconomic backgrounds. The disorders caused due to deficiency of nutritional iodine in the food or diet are called iodine deficiency disorders (IDDs). 1 According to Public Health Standards, an area is declared to be iodine deficient, if 5% or more of schoolgoing children suffer from goiter (enlargement of the thyroid gland situated in the neck). From this point of view, several districts in the state of Gujarat have the problem of iodine deficiency. *Associate Professor **Assistant Professor Dept. of Community Medicine Assistant Professor Dept. of Microbiology Medical College and SSG Hospital, Vadodara Address for correspondence Dr JR Damor D-27, Akanksha Duplex Opposite Laxmikunj Society Laxmipura Road, Gorwa Vadodara , Gujarat jivrajdamor@yahoo.co.in Major activities of National Iodine Deficiency Disorders Control Programme (NIDDCP) are to conduct surveys to assess the magnitude of the IDDs, monitoring of iodized salt consumption, laboratory monitoring of iodized salt, urinary iodine salt concentration and health education and publicity. 1 It is a well-established fact that with the exception of certain types of goiter, IDDs are permanent and incurable. But, these disorders can be easily prevented. The simplest method to prevent the broad-spectrum of IDDs is to consume iodized salt daily. This is the most effective and inexpensive mode to prevent these disorders. Iodized salt should ensure availability of not <150 µg of iodine per person per day. Since salt is consumed by all every day, the supply of iodized salt will ensure the availability of iodine for normal body function. The average consumption of iodized salt per person per day is about 10 grams. This consumption is in moderate amounts. The Central Government had issued a notification banning the sale of noniodized salt for direct human consumption in the entire country with effect from 17th May, 2006 under the Prevention of Food Adulteration Act Starting with Bharuch district in 1982, the State Government brought the entire state under IDD Control 560 Indian Journal of Clinical Practice, Vol. 23, No. 9 February 2013

2 Programme in a phased manner by the year Surveys conducted by the Preventive and Social Medicine (PSM) Dept. of the Govt. Medical Colleges in the state show that IDDs continue to be a health problem in several districts of the state. The high prevalence rate was found in Dangs, Bharuch and Valsad districts. 2 The geographical difference reflects the difference in iodine content in drinking water and to some extent in milk. 3 Aims and Objectives To determine median urinary iodine excretion in samples of school children. To assess iodine level in salt samples in households and at retail shops. To assess the availability of iodized salt and information, education and communication (IEC) material at public distribution system shop. Materials and Method The survey for IDDs at Dahod district was conducted by population proportionate to size (PPS) cluster sampling. Selection of villages/wards by PPS was done from list of villages/wards along with the population from the latest census. The data are available for all districts of the country on CD from Registrar General Office. A sample of 30 villages/wards had to be selected from the district. The method of sampling used was PPS systematic sampling. A sample of 90 children (45 boys and 45 Girls) of age group of 6-12 years from the school and in each cluster, seven urine samples of boys and seven samples of girls were collected and sent to the public health laboratories. From each cluster, salt samples were collected from a minimum of 10 houses and tested with the use of spot salt testing kit for the presence of iodine. Limitations: As it is a cross-sectional study, children who were not present in school at the time of study could not be examined. Results and Review of Literature The median urinary iodine level is 115 μg/dl. The proportion of samples with urinary iodine <50 μg/dl was found to be 15.6%, which is <20% (Table 1). Thus, this corresponds to the category of adequate iodine nutrition as per WHO guidelines for monitoring for IDDs. The age-wise distribution of urinary iodine showed that the proportion of children with urinary iodine excretion <100 μg/dl was lowest in the 6-year age group, whereas the highest proportion was found in the 10-year age group (Fig. 1, Table 2). The gender-wise distribution of urinary iodine excretion showed that the proportion of children with urinary iodine excretion >100 μg/dl was almost similar among both the genders (Fig. 2, Table 3). A population based cross-sectional study evaluated the iodine status among <100 µg/dl >100 µg/dl 100% 90% 80% 70% Percentage 60% 50% 40% 30% 20% % 0% Total Age (years) Figure 1. Age-wise distribution of urinary iodine. Indian Journal of Clinical Practice, Vol. 23, No. 9 February

3 3% Boys 4% Girls 15% 8% 57% 25% 58% 30% <20 µg/dl µg/dl <20 µg/dl µg/dl µg/dl 100 µg/dl µg/dl 100 µg/dl Figure 2. Gender-wise distribution of urinary iodine excretion. The gender-wise distribution of urinary iodine excretion shows that the proportion of children with urinary iodine excretion >100 μg/dl was almost similar among both the genders. Table 1. Distribution of Urinary Iodine (n = 400) Urinary iodine level Number % <20 μg/dl % μg/dl % μg/dl % <100 μg/dl % 100 μg/dl % Total % primary school children of Dhankuta and Dharan in eastern Nepal. The median urinary iodine excretion in primary school children of Dhankuta and Dharan in eastern Nepal were μg/dl and μg/dl, respectively. The percentage of salt samples containing iodine >15 ppm (parts per million) was 81.3% in Dhankuta and 89.6% in Dharan. 4 Horton et al observed that median urinary iodine excretion was significantly and positively related to household availability of iodized salt for developing countries. 5 Table 2. Age-wise Distribution of Urinary Iodine Age (years) Samples collected <20 μg/dl μg/dl μg/dl <100 µg/dl 100 μg/dl No. % No. % No. % No. % No. % Total Indian Journal of Clinical Practice, Vol. 23, No. 9 February 2013

4 Table 3. Gender-wise Distribution of Urinary Iodine Excretion Gender Samples collected <20 μg/dl μg/dl μg/dl <100 μg/dl 100 μg/dl No. % No. % No. % No. % No. % Male Female Total Table 4. Taluka-wise Urinary Iodine Excretion Taluka Total samples taken Median urinary iodine excretion (20 μg/dl) <20 μg/dl μg/dl μg/dl 100 μg/dl No. % No. % No. % No. % Dahod Devgadhbaria Dhanpur Fatehpura Garbada Jhalod Limkheda Total The median urinary iodine excretion is <100 µg/dl for Dhanpur, Jhalod, Fatehpura and Limkheda and it is >100 µg/dl for the rest of the Talukas. In a study of more than 2000 school children aged 6-12 years from Rajkot district, India, the median urinary iodine excretion was 110 μg/dl. Iodine level >15 ppm was found in 81% of salt samples tested at household level. 6 Urinary iodine excretion level was <100 μg/dl in 42.9% talukas and >100 μg/dl in 57.1% talukas (Table 4). Out of 300 salt samples, 207 samples (69%) had >15 ppm iodine present (Table 5). Iodized salt was available in majority of private shops (88.8%) in the villages (Table 6). Conclusion The proportion of samples with urinary iodine <50 μg/dl was found to be 15.6%, which is <20%. Thus, this corresponds to the category of adequate iodine nutrition as per WHO guidelines for monitoring for IDDs. The age-wise distribution of urinary iodine showed that the proportion of children with urinary iodine excretion <100 μg/dl was lowest in the 6-year age group, whereas the highest proportion was found in the 10-year age group. Sixty-nine percent contained >15 ppm iodine; 30% of the salt samples were noniodized. There was no genderwise difference in urinary iodine excretion. More than 50% talukas had urinary iodine excretion levels >100 μg/dl. Recommendations In Dahod district, Gujarat, 30% salt samples were found to be noniodized; hence, there is a need to create awareness among community people and school children about iodized salt by using IEC materials. To make available iodized salt in all public distribution shops. Ten percent of private shops had noniodized salts, so there should be a strict implementation of ban on selling of noniodized salt. Indian Journal of Clinical Practice, Vol. 23, No. 9 February

5 Table 5. Use of Iodized Salt at Household Level Cluster 0 ppm <15 ppm 15 ppm Total samples No Total 89 (29.7%) 4 (1.3%) 207 (69%) 300 Out of 300 salt samples, 207 samples (69%) contained >15 ppm iodine. Suggested Reading 1. Revised Policy Guidelines on National Iodine Deficiency Disorders Control Programme. National Rural Health Mission IDD & Nutrition Cell, Directorate General of Health Services, Ministry of Health & Family Welfare, Government of India New Delhi, Revised Edition, October Table 6. Distribution of Private Shop with Respect to Salt Iodization Status Name of Taluka Salt Total Iodized Noniodized Fatehpura Jhalod Limkheda Dahod Devgadhbaria Dhanpur Garbada Total Iodized salt was available in majority of private shops (88.8%) in the villages. 2. State Nutrition cell, Government of Gujarat Document on Iodine deficiency Disorders Control Programme: Gujarat, Pedersen KM, Laurberg P, Nohr S, Jorgensen A, Anderson S. Iodine in drinking water varies by more than 100-fold in Denmark. Importance for iodine content of infant formulas. Eur J Endocrinol 1999;140(5): Gelal B, Chaudhri RK, Nepal AK, Sah GS, Lamsal M, Brodie DA, et al. Iodine deficiency disorders among primary school children in eastern Nepal. Indian J Pediatr 2011;78(1): Horton S, Miloff A. Iodine status and availability of iodized salt: an across-country analysis. Food Nutr Bull 2010;31(2): Chudasama RK, Verma PB, Mahajan RG. Iodinenutritional status and goiter prevalence in 6-12 years primary school children of Saurashtra region, India. World J Pediatr 2010;6(3): Chudasama R, Patel UV, Patel RR, Verma PH. Iodine deficiency disorders in 6-12 years - old rural primary school children in Kutch District, Gujarat. Indian Pediatr 2010 Nov 30. pii: S [Epub ahead of print]. 8. Misra S, Kantharia SL, Damor JR. Prevalence of goitre in 6-12 years school-going children of Panchmahal district in Gujarat, India. Indian J Med Res 2007;126(5): Biswas AB, Chakraborty I, Das DK, Biswas S, Nandy S, Mitra J. Iodine deficiency disorders among school children of Malda, West Bengal, India. J Health Popul Nutr 2002;20(2): Kapil U, Sharma TD, Singh P. Iodine status and goiter prevalence after 40 years of salt iodisation in the Kangra District, India. Indian J Pediatr 2007;74(2): Indian Journal of Clinical Practice, Vol. 23, No. 9 February 2013