Research Paper Microbial contamination levels in the drinking water and associated health risks in Karachi, Pakistan Rafat Amin, Midhat Batool Zaidi, Saima Bashir, Raq Khanani, Rukhsana Nawaz, Shaukat Ali and Sadaf Khan ABSTRACT The current study aimed to assess the microbial quality of municipal (tap) and ground (borehole) water in Karachi, Pakistan. A health survey was also conducted to assess possible health risks of the drinking water. Fifty water samples (n ¼ 25 each of tap and ground water) were collected from various locations of ve administrative districts of Karachi for bacteriological analysis. In addition, a survey was conducted to assess the impact of drinking water on the health of city residents. Microbiological analysis results showed the presence of total coliform in 48 out of 50 (96%) tested samples. The total viable plate count at 37 C was >200 CFU/ml in the majority of the collected samples which exceeded the permissible limit set by the World Health Organization (WHO) and the Pakistan Environmental Protection Agency. To evaluate the health risk of contaminated water, a total of 744 residents were interviewed. The information acquired from this eld work revealed a high prevalence of waterborne diseases in the order of diarrhea and vomiting > skin problems > malaria > prolonged fever > eye problems and jaundice. To solve water and environmental problems, awareness and regular monitoring programs of water management and safe disposal of waste have been suggested. Rafat Amin Shaukat Ali Department of Pathology, Dow International Medical Collage, Dow Research Institute of Biotechnology and Biomedical Sciences, Dow University of Health Sciences, Ojha Campus, Karachi, Pakistan Midhat Batool Zaidi Dr Panjwani Center for Molecular Medicine and Drug Research, International Center of Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan Saima Bashir Institute of Biological, Biochemical and Pharmaceutical Sciences, Dow University of Health Sciences, Ojha Campus, Karachi, Pakistan Raq Khanani Liaquat College of Medicine and Dentistry, Darul Sehat Hospital, Karachi, Pakistan Rukhsana Nawaz Behavioral Neuroscience Lab, College of Humanities and Social Sciences, United Arab Emirates University, Al Ain, United Arab Emirates Sadaf Khan (corresponding author) Department of Biochemistry, Dow International Medical College, Dow Research Institute of Biotechnology and Biomedical Sciences, Dow University of Health Sciences, Ojha Campus, Karachi, Pakistan E-mail: sudafkhan@gmail.com; sadaf.khan@duhs.edu.pk These authors contributed equally to this work. Key words | ground water, microbial quality, municipal supplied water, public health, waterborne diseases 319 Research Paper © IWA Publishing 2019 Journal of Water, Sanitation and Hygiene for Development | 09.2 | 2019 doi: 10.2166/washdev.2019.147 Downloaded from https://iwaponline.com/washdev/article-pdf/9/2/319/643616/washdev0090319.pdf by guest on 22 May 2020