The catastrophe set off an unexpected shortage of iodine, leaving children in faraway countries vulnerable to cognitive deficits.
The tsunami and nuclear disaster in Fukushima, Japan, now threatens the developing brains of children in Cambodia — but not for reasons that were ever expected.
Cambodia has long struggled with iodine deficiency. The element is crucial to early brain growth: When pregnant women and their infants have low levels, the children can permanently lose 10 to 15 I. Q. points. Iodine deficiency is considered the world’s leading preventable cause of mental impairment.
But there is a cheap, easy remedy: iodized salt. As salt is cleaned and packaged, potassium iodate may be sprayed on it, normally at a cost of only a dollar or two per ton.
That means, nutrition experts say, that the I. Q. of entire nations can be raised 10 points for just a nickel per child per year.
Cambodia was making great progress against iodine deficiency until 2011, according to a report published in 2015 by the Iodine Global Network, a public-private partnership combating the deficiency.
Like many countries with regular flooding, Cambodia’s soil has little natural iodine, so its crops also contain little. In 1997, according to Unicef, almost a fifth of its population had goiters — swollen thyroid glands in the neck that indicate serious deficiency, which can also cause dwarfism and cretinism.
In 1999, with help from donors, Cambodia began iodizing table salt. In 2003, the Parliament and king made it mandatory. Dozens of small producers in Kampot and Kep provinces who made salt by evaporating seawater formed a cooperative that was given potassium-iodate spraying machines.
From 2000 to 2011, use of iodized salt rose to 70 percent from 13 percent of households, according to a 2015 study in the journal Nutrients. Market sampling in 2008 found only 1 percent of salt with no detectable iodine.
But then things began falling apart.
In 2010, Unicef and other donors turned responsibility for iodination over to the government and salt producers.
