China will go on using fortified salt to fight iodine deficiency, said health officials marking the 10th anniversary of introducing iodized salt to the people in South China's Hainan Province.

"The average intelligence quotient (IQ) of Chinese children has been rising in the last decade and by now the threat of hypogenetic brain disorder caused by iodine deficiency which has affected the Chinese for centuries is at its lowest ever," said Vice Minister of Health Wang Longde.

The fortified salt has not only cut the incidence of iodine deficiency-related diseases but also raised the quality of the Chinese nation, Wang told a recent meeting marking the 13th national day for prevention and control of iodine deficiency.

A survey conducted in 11 provinces in 2002 showed that the children's average IQ in most provinces was below 100, while another survey in 2005 showed the average IQ had reached 103.5, a progress owed to the promotion of iodized salt, he said.

China has 720 million people living in iodine-deficient regions. The government started an iodized salt program in 1995.

Last year, the country's gross production of iodized salt reached 7.2 million tons, according to Chen Jixiang, deputy head of the China Endemic Association.

The epidemiological research conducted last year showed that 90.2 percent of Chinese ate qualified iodized salt and the rate of children's neck goiters dropped to 5 percent, two key international indices for eradication of iodine deficiency.

However, challenges and problems are still faced by control of iodine deficiency, noted Wang.

People in western regions, including Tibet, Xinjiang and Qinghai, are still menaced by a lack of iodine, while coastal regions like Hainan, Zhejiang and Fujian are seeing disturbance in the salt market caused by non-iodized salt or salt used for industrial purposes.

"Governments should play an active role in fighting substandard fortified salt, not just focusing on economic gains," Wang said, urging local authorities to adjust the structure of the salt industry and cut off the source of non-iodized salt.

Moreover, in the regions which have ensured iodized salt consumption are now witnessing a rise in non-iodized salt consuming rates. In Guangdong, Hebei and Guangxi, the rates rebounded to 20 percent in 2004 and 2005, according to Wang.

"The rebound in some places indicates that the prevention and control of iodine deficiency needs continuous attention and efforts," said Liu Shoujun, a researcher with the endemic control center under the China Center for Disease Control and Prevention.