Reclaimed water: A safe irrigation water source?

•Salts and nitrogen were the major risk sources of reclaimed water irrigation.•Problems due to salts and nitrogen can be managed by adjusting irrigation practices.•The risks of heavy metals and PPCPs in reclaimed water are low under normal cases.•Reclaimed water irrigation should be encouraged and promoted given its great benefits.

Municipal wastewater reclamation and reuse provides an effective way to solve water resource problems in arid and semi-arid regions. Irrigation is the major reuse for reclaimed water. In this paper, we analyzed the benefits and risks associated with reclaimed water irrigation to demonstrate that it is a safe water resource when appropriately applied. The analysis showed that reclaimed water is an economical water resource with potential benefits in ameliorating soil health conditions and saving fertilizer. Salts, nitrogen and pathogens were the major risk sources for reclaimed water irrigation, while risks associated with heavy metals and emerging contaminants were low. Risk management practices were summarized. Given that there are huge potential benefits and the risks can be controlled by proper field management, irrigation with reclaimed water should be encouraged and promoted.