Water of high content iodine existed in shallow depth in the northeast area, while it did in deep depth in the southeast area.

西南部地区的高碘水几乎都是浅层，西北部的高碘水则以深层居多。

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Dahl says that this may have been made worse because the area had a high incidence of goiter, indicating that people did not have enough iodine to begin with.

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