As of?March 29, traces of radioactive iodine-131 had been detected in aerosol samples gathered at monitoring sites in Shanghai, Tianjin and Chongqing cities as well as in Inner Mongolia, Guangxi and Ningxia Hui Autonomous Regions.

Following?the nuclear radiation leak in Fukushima, Japan, in the wake of the devastating earthquake and tsunami three weeks ago, China has been monitoring the levels of radioactive iodine in the air.

Twelve provinces – Hebei, Shanxi, Shaanxi, Jilin, Heilongjiang, Jiangsu, Zhejiang, Fujian, Henan, Guangdong, Anhui and Sichuan – are similarly affected. Iodine concentrations are below 100,000th becquerel per cubic metre.

The authorities have assured the people that the “extremely low levels of radiation” do not pose any threat to public health or warrant any specific protective action.