Reporter: As good quality water resources are becoming increasingly scarce and the process of urbanization proceeds relentlessly, wastewater is becoming a valued resource. However, without effective management, the use of untreated wastewater, excreta and greywater carries serious health risks. The third edition of the WHO Guidelines for the safe use of wastewater in agriculture and aquaculture provide the necessary know-how and good-practice information through the entire re-use process.

Dr. James Bartram from the Water, Sanitation and Health Department of the World Health Organization explains the purpose of the guideline.

"The purpose of the guidelines is to maximize public health protection and beneficial use of important resources."

The Guidelines provide an integrated preventive management framework for safety and protection of the health of the people using wastewater or consuming products grown with wastewater or excreta.

Dr. Peter Edwards from Asian Institute of Technology talks about its importance to China.

"Well it is very useful for China. I mean waste re-use in the richer areas is decreasing but there is a lot of water pollutions because the sewage is not being treated properly and also the water is being used to irrigate crops. So they are highly relevant for China."

Just as Dr. Edwards says, the most important thing is to carry out the Guideline in China, which has a huge population and a relatively scarce water resources.

Xu Weiyi, CRI News