Iodine is an essential micronutrient to sustain human and animal health, yet it is one of the most common micronutrient deficiencies in malnutrition. Globally it is estimated that 2.2 billion people in the world are at a risk of iodine deficiency. Iodine deficiencies can cause a wide range of physiological abnormalities (Iodine Deficiency Disorders), mainly related to defective mental development and brain damage.
The content of iodine in food depends on the iodine content of the soils in which crops are grown. In the Western diet, the most common source of iodine is iodized salt however, in certain countries, iodization of salt is inefficient due to infrastructure or cultural problems. Moreover, iodized salt does not reach the root cause of iodine deficiency. People at risk from iodine deficiency are often the poorest populations living on subsistence agriculture and in an environment that is unable to provide the correct mineral balance.
In Xinjiang Province, in the North West of China, the soil is particularly poor in iodine with an associated high infant-mortality rate. In 1997, the Xinjiang Uiger Autonomous Region Health Bureau, with the support of the Thrasher Foundation, the Joseph P. Kennedy Jr Foundation, Kiwanis International and UNICEF, launched the Iodine Dripping Project (XIDP). This project aimed at supplying the water irrigation system with iodine using an iodine fertilizer dripping technique, called fertigation. With this technique, the iodine from the treated water is absorbed by the soil and progresses through plants and animals that eat the iodine-rich plants. At the top of the food chain, people eat these iodine–rich foods therefore increasing their iodine levels.
The iodine fertilizer dripping project has revealed unprecedented results. Not only did the iodine levels in women and children rose, halving the rates of infant mortality and improving children’s intelligence quotient, but also local livestock production increased by 40% in the first year. The livestock production increase contributed to raise the average family income by 5% annually.
The iodine dripping project in Xinjiang has also revealed that a single dripping can provide enough iodine for at least six years.
This experience demonstrates that micronutrient fertilizers can provide an efficient and cost-effective solution to malnutrition while improving the social and economical conditions of people in developing countries.