Agricultural use of sewage sludge : a literature review

Stricter regulations on discharge of sewage into waters, higher costs of alternate disposal procedures, and higher prices of chemical fertilizers have increased interest in the use of sewage sludge in crop production. This review addresses the benefits and risks of agricultural use of sewage sludge. Topics evaluated in this study are the biological, chemical, and physical aspects of sewage sludge relating to trace elements, pathogens, nitrogen, and phosphorus and also the economic aspects of land application of sewage sludge. For each topic, additional research needs are identified.