Assessment of microbial levels in the Plankenburg and Eerste Rivers and subsequent carry-over to fresh produce using source tracking as indicator

摘要: The agricultural sector of South Africa is currently facing a serious water crisis. decreased availability as result climate change and the constantly growing population has left many farmers increasingly dependant on surface primary source irrigation. Urbanisation along with out-dated insufficient wastewater treatment works have all contributed to polluting large volumes these resources. Consequently, been forced use irrigation water, not only poor quality, but often which polluted untreated sewage. As result, this project aimed at investigating link between quality impact safety fresh produce. A base-line microbial load three sites Plankenburg Eerste Rivers was established using standard methods for detection indicator organisms such total faecal coliforms, Escherichia coli Enterococci well potential pathogens that included Salmonella, Listeria, Staphylococcus, endosporeformers aerobic colony counts. Chemical parameters pH, alkalinity, conductivity chemical oxygen demand (COD) were also monitored, correlated pollution levels in rivers. High coliform E. concentrations, ranging from 310 7 x 10 cfu.100 mL 230 mL, respectively, detected. recommended guidelines ≤1 000 (WHO, 1989) ≤4 (DWAF, 2008) coliforms exceeded, indicating thus high health risk. This risk confirmed when Aerococcus viridans, Klebsiella, Listeria monocytogenes Salmonella typhimurium detected sites. carryover rivers produce (green beans grapes) investigated by comparing recovered Faecal coli, Enterobacter aerogenes, L. innocua, grayi, Staphylococcus aureus sample types, similarity populations found river, Thus, transfer strong possibility. build-up green multiple irrigations an increase Stellenbosch University http://scholar.sun.ac.za