The standards for irrigation water quality are currently provided by global and national guidelines that are mostly based on the assumption that threshold values could be applied to protect crops. This approach can create problems for a largely unrecognized group of people who make use of irrigation water for non-agricultural purposes. At the same time, increasing water scarcity will lead to the need for recycling of water in irrigated river basins, and the use of low quality irrigation water. Apart from hazards of high pollutant levels, a sustainability criterion has to be included in the water quality guidelines to account for long-term low-level application of certain pollutants that can accumulate in the environment. Using the example of cadmium, it is argued that the current guidelines need to be revised and should take local factors and future developments into account.