Staving off Goitre and Cretinism

It is through salt that the iodine deficiency endemic to the Himalaya -causing goitre and cretinism – can be tackled. If a permanent system of salt iodization and distribution were set up, the Himalaya would be rid of cretinism and other associated disorders. Yet salt, the all-important commodity, is hardly ever discussed at the national policy level.

Iodine is a trace element found in the soil. Through time, iodine has "leached" from mountains to plains and then to the sea. This leaching has given the soil of many highlands and flood-prone areas, including that of Bhutan, India, Nepal and Bangladesh, very low iodine content. As a result the quantity of iodine in food crops is very low. Being an essential micronutrient, a lack of iodine in the diet leads to Iodine Deficiency Disorders (IDD) even if the diet is otherwise well-balanced.

Experts say some degree of goitre is present in more than one half of the population of Bhutan and Nepal — its prevalence surpassing that of India and other neighbouring countries. Cretinism is characterized by mental retardation, deaf-mutism, and lack of muscular coordination, and it also occurs in perhaps one out of every 50 persons.

The eradication of goitre and cretinism today ranks as one of the most important public health in the Himalaya. In Nepal, the iodine supplement has normally been through salt. Iodized oil injection, another method, is used in high risk areas where iodized salt has not penetrated. While oil injections are undoubtedly effective, especially in preventing cretinism in newborns, the method is more of an interim measure. At the present level of technology, iodized salt remains the chosen vehicle to overcome IDD because of the country's transportation problems, consumer resistance, finance, and the dependence on ad-hoc foreign assistance programmes.

The peculiarities of the consumption and distribution of salt must be under-stood in order to better dispense it. In terms of consumer preference, Kathmandu's population prefers crystal salt, while the Terai people use pow-dered salt, which is a more efficient retainer of iodine. In the high Himal and remote Mahabharat Lekh regions, those most likely to suffer from iodine deficiency prefer rock salts from the salt pans of Tibet, which cannot be iodized for logistical and technical reasons. While Tibetan salt comprises 5 percent of the salt used in Nepal, most of it is consumed by people living in zones that are hyperendemic in IDD.

Nepal's Salt Trading Corporation (STC) is a franchise that has been importing and distributing iodised salt throughout the country since 1973. The merit of the franchise is that the quality of salt and its distribution are centrally controlled and monitored, which is a more difficult prospect in India and Bangladesh. The drawback is that Salt Trading, as a profit-making entity, is responsive to market forces. Salt iodization requires subsidy and social commitment, both of which Salt Trading may not be able or willing to give. While the agency is considered to be more efficient than most government departments or individual businesses, its distribution system is constrained by insufficient funds. Therein lies the greatest obstacle to the spread of iodized salt in Nepal.

Initially, the iodized salt programme imported iodized salt from India, but because of the time lag between import, distribution and consumption, the plan proved ineffective. Much of the iodine evaporated in transit before the salt was ever used.

Today, Salt Trading has three iodizing plants – in Bhairahawa, Birgunj and Biratnagar. Because of its limited capacity and transportation bottlenecks, the STC is far from able to provide iodine to the whole country. While the total annual consumption of salt in remote areas is about 6,000 tonnes a year (annual consumption country-wide is 120,000 tonnes), between 1973 to 1988 only 14,300 tonnes of iodized salt had been sent to these areas. The gap in supply is met from barter trading with Tibet or by buying Indian salt from individual traders. Thus, even though STC is theoretically responsible for providing salt throughout the country, this is not so in practice.

STC plans to have six iodization plants in the near future. But even if salt is iodized in Nepal, there is significant evaporation of the iodine by the time it is consumed. Iodized salt has a half-life of about nine months, and the salt supplies often languish in the godowns of Salt Trading and merchants for much of this period. In addition, the people of the remote hills, who are most prone to IDD, tend to stock their salt longer as they are further away from the road head.

One means of ensuring quicker turn-over of salt is by packaging it in smaller packs of 1kg or .5kg using polyethylene, so that the iodine is retained. If all goes well, Salt Trading Corporation will soon have its own packaging plant. In addition to lining large bags and small packages with polyethylene, calcium carbonate will be added to make the iodine and salt bond more stable. This would double the iodized salt's life to about 18 months. There are also plans to increase the amount of iodine in the salt from the present 15 parts per million (ppm) to 4Oppm or 5Oppm. This is expected to counteract the evaporation that takes place during transit and storage.

Iodine Deficiency Disorders cannot be eradicated like smallpox or other infectious diseases; iodine fortification will always be required in the Himalaya because of the absence of an essential element in the soil. Therefore, questions of whether to iodize or not, and of cost-benefit are moot. All salt used in Nepal is required to be iodized, and optimally packaged. The most important question, therefore, is the affordability of optimally iodized salt. In Nepal it is transportation, not iodizing and packaging, that take up the bulk of the costs.

According to Salt Trading, packaging costs will raise the price of 1kg of salt from Rs. 2 to Rs. 4 in Kathmandu and other urban centres. Remote districts in Nepal are already paying from Rs. 8 to Rs. 12 per kg, even though a transportation subsidy is gauged according to how far the salt has to be carried. In the remotest areas of Humla and Darchula, even with a 40 percent subsidy, people pay an extremely high price for salt. With so much money spent on transport, there is no benefit in distibuting non-iodized salt.

Since 1973, transportation subsidies for iodized salt have been provided by the Indian Government under an IDD eradication programme. The grant period ends in 1991, by which time STC hopes to create a comprehensive country-wide network of iodized salt distribution, as well as fully operational iodizing and packaging plants. There may be delays in meeting the target -¬and it is already too late to consider what to do after 1991. Will. Nepal request a renewal of the grant, approach international agencies, or will bilateral donors pick up the tab? Whatever, the foundations built since 1973 should not be allowed to fall apart.

But for how long can Nepal depend on outside assistance and subsidy to distribute an essential commodity? No doubt Nepal's terrain poses a challenge. Indigenous, and more importantly, sustainable iodization and distribution systems have to be set up. Since iodized salt will be needed well into the future, foreign aid should not be expected to sustain such an indefinite programme.

One way of maintaining a permanent programme is to pass on the cost of transportation and iodization to the public. However, as even with subsidy, the people in the high Himalaya already pay far more than they can afford, given the level of their cash income. If the government could manage it, urban dwellers should be made to share the cost of iodized salt for rural areas. Until the government is capable of enforcing such an "equalising function" it must itself subsidise salt iodization and distribution, and consider it a part of the permanent government programme.

Shanta Dixit is an epidemiologist.