Bacterial contamination and health risks of drinking water from the municipal non-government managed water treatment plants Salama A. Ouf & Ramy S. Yehia & Ahmed S. Ouf & Rania F. Abdul-Rahim Received: 11 July 2018 /Accepted: 15 October 2018 # Springer Nature Switzerland AG 2018 Abstract Water quality and bacterial contamination from 18 drinking water municipal plants in three loca- tions at Giza governorate were investigated. The aver- age total count of bacteria detected after four stages of treatments in the investigated plants was 32 CFU/1 mL compared to 2330 cfu/mL for raw water, with a reduc- tion percentage of 98.6. Although there is a relatively high removal percent of bacterial contamination from the water sources, however, several bacterial pathogens were identified in the produced water prepared for drinking including Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, and Shigella spp. After 3 days of water incubation at 30 °C, the amount of bacterial endotoxins ranged from 77 to 137 ng/mL in the water produced from the municipal plants compared to 621–1260 ng/mL for untreated water. The main dis- eases reported from patients attending different clinics and hospitals during summer 2014 at the surveyed lo- cations and assuredly due to drinking water from these plants indicated that diarrheas and gastroenteritis due to E. coli and Campylobacter jejuni constituted 65.7% of the total patients followed by bacillary dysentery or shigellosis due to Shigella spp. (7.9%) and cholera due to Vibrio cholera (7.2%). There was an increase in serum aspartate aminotransferase (AST), alanine ami- notransferase (ALT), and alkaline phosphatase (ALP) as well as urea and creatinine values of guinea pigs con- suming water produced from the non-governmental plants for 6 months indicating remarkable liver and kidney damages. Histological sections of liver and kid- ney from the tested animal revealed liver having bal- looning degeneration of hepatocytes and distortion and fragmentation of the nuclei, while the section of the kidney showed irregularly distributed wrinkled cells, degenerated Bowman’ s capsule, congested blood ves- sels, and inflammatory cells. Keywords Drinking water . Treatment plants . Contamination . Bacteria . Disease outbreak . Liver and kidney damage Introduction A safe or reliable year-round supply of drinking water remains a problem for at least one-third of the popula- tion of developing countries (Wegelin et al. 1994). Peo- ple are facing a problem throughout the world due to water pollution, the inequitable distribution and trans- port (Moerman et al. 2014; Nawab et al. 2016; Zlatanović et al. 2017; Chena et al. 2018). An adequate supply of safe drinking water is one of the major Environ Monit Assess (2018) 190:685 https://doi.org/10.1007/s10661-018-7054-z Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10661-018-7054-z) contains supplementary material, which is available to authorized users. S. A. Ouf (*) : R. S. Yehia : R. F. Abdul-Rahim Botany and Microbiology Department, Faculty of Science, Cairo University, Giza 12613, Egypt e-mail: saoufeg@yahoo.com e-mail: salama@sci.cu.edu.eg A. S. Ouf Kasr Al Ainy Medical School, Cairo University, Cairo, Egypt