Extremely low levels of radioactive material have been detected in the air above the coastal area in southeast China yesterday, said China's National Nuclear Emergency Coordination Committee.

But public health and the environment will be unaffected, the committee said.

Iodine-131, a radioactive material, has been found in the air above Jiangsu Province, Shanghai City, Zhejiang Province, Anhui Province, Guangdong Province and Guangxi Zhuang Autonomous Region. The material was believed to be released from the crippled nuclear power plant in Japan's Fukushima Prefecture.

Experts said there was no need to take protective measures as the radioactivity was extremely low. According to the committee, the levels of radioactive material were below one-hundred-thousandth of the natural background radiation.

So far, the nuclear crisis at Japan has no major impact on the environment and people's health in China. The conclusion was based on the monitoring results of a Beijing-based emergency response center under the World Meteorological Organization, the International Atomic Energy Agency, the State Oceanic Administration and the Ministry of Environmental Protection.

During the weekend, low levels of radioactive material were detected in the air above Heilongjiang Province in northeast China, but experts said public health and the environment wouldn't be harmed.

The Ministry of Health has launched a campaign in 14 cities and provinces in northeast area and coastal area to monitor the level of radioactive material in foods and tap water.