Ghader Ghanizadeh - Department of Environmental Health, Faculty of Health, Baqiyatallah University of Medical Sciences, Tehran, Iran
Ahmad Reza Yari - Research Center for Environmental Pollutants, Qom University of Medical Sciences, Qom, Iran

Background & Aims of the Study: The safe drinking water providing is one of the mostcrucial objections in these centenaries. Bacterial water contamination and high rate of morbidityand mortality is crucial health threat. Efficiency of potassium persulfat (KPS) associated solardisinfection as a novel water disinfection technology was evaluated in batch scale experiments,using Ent. faecalis (ATTCC 29212).Material and Methods: This research is a descriptive and experimental study which done onTehran city, Iran. Ent. faecalis (ATTCC 29212) was provided in standard form from referencelaboratory. Desired bacterial density in water was prepared by Mc Farland method. Waterspecimens were exhibited with solar radiations from 10 a.m to 16 p.m of Tehran local time. Allexperiments were conducted into 1.5 L volume of Damavand bottled water. Non-injured bacteriacells were detected by plating onto Bile Esculin azide agar media. Turbid water samples wereprovided by spiking of sterile slurry. Contact time (1-6 h), turbidity (30-200 NTU), KPSconcentration (0.1, 0.7, 1.5 and 2 mMol/l), Ent. faecalis density(1000 and 1500 cell/ml) and UVintensity were independent and disinfection efficiency was a dependent variable, respectively.Results: Intensity of UVA solar irradiation varied from 3770 to 6263.3 μW/Cm2, with thehighest value was measured on 13.30 p.m. In single SODIS and 1 hour contact time, increasingof bacterial closeness from 1000 to 1500 cell/ml implied disinfection performance decreasing inwhich, the vital bacteria was 10 and 20 cell/ml, respectively; but beyond of this contact time, acomplete disinfection was occurred. Disinfection of Ent. faecalis was achieved within 2 h withsingle solar irradiation but KPS associated solar disinfection with applied dosage of KPS providecompletely disinfection in 1 h in which the process efficiency was not influenced by increasingof bacterial density and turbidity up to 200 NTU.Conclusion: Association of KPS with SODIS enhancing water disinfection which can be used inremote area and emergency status.

Drinking WaterBottled WaterDisinfectionSolar irradiationEnterococcus faecalisPotassium PersulfateIran