In order to know the baseline data of water iodine and the iodine nutritional status of 8 - 10 years old children in Chaoyang District of Beijing, to evaluate the current status of iodine deficiency disorders so as to provide a basis for taking targeted preventive measure and adjusting the intervention strategies scientifically.

Multi-stages sampling method was used to select drinking water samples from 43 subdistricts or townships in Chaoyang, and the water iodine content in the drinking water was determined. A cluster sampling method was applied to select 8 - 10 years old children from primary schools in 5 subdistricts or townships, and the iodine contents of urine and salt were determined. And B ultrasonic examination was carried out for diagnosis of thyroid disease.

The median iodine content of drinking water in Chaoyang was 4.85 μg/L, the iodine content of self-provided wells (5.65 μg/L) was higher than that of municipal water (3.80 μg/L, Z = - 3.469, P < 0.05). The coverage rate of iodized salt was 88.06% (177/201) and the qualified rate of iodized salt was 81.59% (164/201). The median urinary iodine was 165.00 μg/L, median urinary iodine in boys (174.00 μg/L) was higher than that of girls (146.00 μg/L, Z = - 2.434, P < 0.05). The goiter rate diagnosed by B ultrasound was 1.49% (3/201), the thyroid nodule rate was 24.88% (50/201).

The iodine content of drinking water in the Chaoyang District is low, and it is still in the external environment of iodine deficiency (< 10 μg/L). The 8 - 10 years old children of Chaoyang show a good iodine nutritional status, however, neither the coverage rate nor the qualified rate of iodized salt has reached the standard of elimination of iodine deficiency disorders, and scientific iodine can not be ignored.

Iodine; Child; Goiter; Thyroid nodule