To assess the prevalence of enlarged thyroid volume (Tvol) in Saharawi refugee children, and their urinary iodine concentration (UIC), and to identify possible sources of excess iodine intake.

A cross-sectional survey was performed during January–February 2007. Tvol was measured by ultrasound and iodine concentration was analysed in casual urine samples, in household drinking water and in milk samples from household livestock.

The study was undertaken in four refugee camps in the Algerian desert.

The subjects were 421 Saharawi children, 6–14 years old.

Enlarged Tvol was found in 56 % (Tvol-for-age) and 86 % (Tvol-for-body-surface-area) of the children. The median (25th percentile–75th percentile, P25–P75) UIC was 565 (357–887) μg/l. The median (P25–P75) iodine concentration in household drinking water was 108 (77–297) μg/l. None of the children had UIC below 100 μg/l, 16 % had UIC between 100 and 299 μg/l, and 84 % had UIC above 300 μg/l. There was a positive association between Tvol and whether the household possessed livestock.

The children are suffering from endemic goitre and high UIC caused probably by an excessive intake of iodine. The excessive iodine intakes probably originate from drinking water and milk.