Health risk assessment for reuse of spent filter backwash water (SFBW) in Saveh water treatment plant

Background: The increase in population growth, industries, and living standards have caused an increasing need for drinking water in many countries. One of the most important ways to deal with water shortage is the reuse or recovery of treated water and wastewater. To ensure the correctness of this work, it is necessary that the health risk assessment be re-examined during use so that consumers do not face serious problems. In this regard, the assessment of health risks assessment for the water recovered from the backwashing wastewater of the Saveh water treatment plant was investigated.Materials and methods: In order to reuse the backwash wastewater from the Saveh water treatment plant, the processes of primary sedimentation and coagulation (in the form of a test jar) were investigated. Metals and heavy metals such as iron, aluminum, lead, arsenic, and cadmium were examined to evaluate health risks. The initial settling time was ۱ hour, the coagulant used was FeCl۳ made in Iran, and heavy metals were also measured with the ICP device.Results: HRIs indices values of Fe, Al, Pb, As and Cd in treated SFBW with primary sedimentation and coagulation were less than “۱” which indicates no risk of exposure to the use of this water.Conclusion: The raw water of the Saveh city treatment plant as well as the backwash wastewater treated with primary sedimentation and coagulation processes have no harmful effects in terms of heavy metals, and its reuse will not pose a risk to the health of the consumer.