China's environment watchdog warned quake survivors should source drinking water away from the rubble of quake-shattered buildings to avoid contamination.

The Ministry of Environmental Protection issued on Tuesday a circular urging authorities in quake zones to ensure drinking water safety.

"Dead bodies, medical wastes and the repeated use of disinfectants and plague prevention drugs also pose great threats to the safety of drinking water," the circular read.

Water from underground sources near quake-shattered building ruins should be avoided for human use, the circular ordered. Local health and disease prevention authorities should provide guidance to local people when fetching water from shallow wells and from rivers in the quake zone.

Water plants in the quake zone should enhance their sterilization process and guard against bacteria, while environment departments increase the frequency of water quality checks, it said.

Once found contaminated, the water must be immediately filtered with activated carbon or treated with advanced oxidation process if it is to be used, it said.

China has repeatedly warned of possible plague in the past few days because it is feared that high temperatures would quicken the rotting of dead bodies in the quake zone.

The 8-magnitude earthquake centered in Wenchuan of Sichuan Province has so far left more than 34,000 people dead as of Monday noon. The final death toll was expected to reach 50,000.

So far, no major epidemic or public health incidents have been reported, according to the country's health ministry.

(Xinhua News Agency May 20, 2008)