Workers at the Beijing Radiation Safety Technology Center conduct tests to detect the level of radioactivity in the air on Tuesday. Feng Yongbin / China Daily

BEIJING - Officials said China will not be affected in the next three days by the rising threat of a wide dispersion of radiation from leaking reactors in Japan.

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Experts in ocean, air and environmental studies assured the public on Tuesday that the radiation leak in Japan is unlikely to reach China in the short term.

"Before Friday, the wind in Japan is expected to blow mainly to the southeast and, since we are to the west of Japan, radioactive pollutants are not likely to reach China," Sun Jun, chief weather forecaster of the China Meteorological Administration and a member of the experts panel of the national nuclear emergency coordination committee, told China Daily on Tuesday.

Sun said wind and a mild rain in Sendai and Fukushima, two of the cities most damaged by the recent tsunami, were blowing toward Tokyo at about 2 to 3 meters a second by 2 pm on Tuesday.

He said a cold front will pass through the quake-stricken areas on Wednesday, causing the temperature to drop by about 3 degrees and bringing light snow or rain.

"Judging by the wind direction predicted for the next four days, the radioactive contaminants are likely to be dispersed inside Japan and the Pacific region," Sun said.

No long-term forecast of wind conditions is now available. The China Meteorological Administration said it has been keeping a close eye on the weather conditions and will deliver a daily weather report to policymakers.

Yu Fujiang, deputy director of the National Marine Environmental Forecasting Center of the State Oceanic Administration, told China Daily on Tuesday that the radiation leaks will not affect China's coastal waters within the next three days.

Yu said the State Oceanic Administration's departments overseeing the Bohai Sea, Yellow Sea, East China Sea and South China Sea began conducting water-quality tests soon after the earthquake and so far has found no evidence of pollution.

Li Yun, a researcher of the center, said chances are low that the radiation leaks in Japan will affect waters near China even in the long run.

"According to our data on tidal movements, the tides near Fukushima generally go to the east, to the Pacific Ocean," Li said.

Since Saturday, when the first of several explosions occurred at a nuclear power plant on Japan's east coast, the National Marine Environmental Forecasting Center has monitored the waters near China and delivered a daily prediction to the State Oceanic Administration.

Li, who is also in charge of the report, said that because of the slow movement of the tides, any resulting pollution is likely to stay within ocean areas near Fukushima, although it may extend northeast of Tokyo and finally flow into the Pacific Ocean.

China's Ministry of Environmental Protection also said China had not been affected as of 10 am Tuesday by the radiation leaks in Japan.

The ministry, which is in charge of nuclear safety in China, said it intensified its monitoring of radiation levels after the March 11 earthquake and tsunami led to the failures of the cooling systems at several Japanese nuclear reactors.

On Saturday, the ministry's department of nuclear safety management began using its website to post up-to-date radiation figures twice a day for 42 Chinese cities, as well as for areas surrounding the country's nuclear power plants. The readings have been all within safe levels.