Red tide is covering 8,000 to 10,000 square kilometres of sea areas, or an area equal to more than 1.3 million soccer fields near Zhoushan, East China's Zhejiang Province.

State Environmental Protection Administration Vice-Minister Pan Yue warned people on Friday about aquatic products from these sea areas, which might cause damage to humans because the red tide contains paralyzing toxins.

Red tide refers to sea water turning red owing to a gathering of plankton on its surface. The plankton organisms reproduce themselves in large quantities due to rich nutrients in the water.

The phenomenon, though colourful in appearance, is very dangerous because it can lead to the death of aquatic life and therefore cause damage to the fishing industry.

According to the Zhoushan maritime environment monitoring station, the red tide started occurring on May 2 in the central and southern parts of the sea areas of Zhejiang Province.

As of Friday, the red tide has shown no signs of fading away. And due to the fact that the current environment in the sea areas is good for the organisms to survive, the tide will likely continue for a period of time.

Pan said pollution of sea water had contributed to the red tide. Sewage caused by daily life and industrial waste always contains substances that can cause water to become too rich in nutrients.

He said the administration is conducting research on curbing the pollution of sea water and setting up an information release system on the sea environment.

The administration is also working together with East China's Jiangsu Province, Zhejiang and Shanghai on the control of sewage discharges into the East China Sea from the three regions.

According to information on the environment of China's sea areas released by the State Oceanic Administration earlier this year, red tide occurred 119 times last year in China's coastal areas, affecting an accumulated area of 14,550 square kilometres.

(China Daily 05/15/2004 page2)