Occurrence of Fungi in Drinking Water Sources and Their Treatment by Chlorination and UV-Irradiation

Abstract

A TOTAL of 54 cfu/ml fungal species were isolated from 9 water samples collected from Nile water, Water Treatment Plant (WTP) and tap water in many governorates in Egypt. The fungal species Aspergillus alutaceus, A. flavus, A. fumigatus, A. niger, A. sulfurous, A. terreus, Penicillium chrysogenum, P. globrum and Trichoderma viride were isolated from water samples. Nile water (S1) was polluted with the highest fungal count and diversity followed by treated tap water in Al Sharqia (S5) Governorate. The physicochemical analysis revealed higher COD and conductivity in Al Sharqia tap water sample than that in untreated Nile water sample which may be due to the old rusted distribution systems or heavy metals contamination. Laboratory scale treatment of tap water in Al Sharqia sample (S5) indicated that single treatment with chlorination was not efficient to eliminate fungal contamination except by using high chlorine concentration with long exposure time. Similarly single UV treatment to drinking water was not effective enough. Combination between UV irradiation followed by chlorination exerted synergistic effect and disinfected water from fungal contamination in very short exposure time and very low chlorine concentration.