Rates of experimental microbiological contamination of fish exposed to polluted water

• Published in: Water research (Oxford) 1992, Vol.26 (12), p.1621-1627
• Main Authors: Fattal, B., Dotan, A., Tchorsh, Y.
• Format: Article
• Language: English
• Subjects: Aeromonas; Agnatha. Pisces; Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; E. coli; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; enterococci; Escherichia coli; F+ coliphages; fecal coliforms; fish contamination; Fundamental and applied biological sciences. Psychology; Marine; poliovirus I; wastewater
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/0043-1354(92)90161-V

Fish inhabiting fecally polluted bodies of water are often used for human consumption. Such fish can be contaminated by enteric human pathogens and may pose a potential risk to public health. Controlled experiments with 132 fish of 100 g average weight were conducted to evaluate the rate of contamination of various tissues of fish (tilapia hybrids). The fish were exposed to E. coli introduced into the ambient water at concentrations of up to 10 6 cfu/ml. Additional experiments were conducted with diluted wastewater containing Aeromonas, enterococci, fecal coliform and F+ coliphages. In another experiment poliovirus I was also added. The highest bacterial concentrations were recovered from the digestive tract (DT), some 5–24 h following exposure, with DT levels essentially similar to those in the inoculated water. In the E. coli experiments, geometric mean levels of about 10 2 cfu/cm 2 were recovered from the skin, 26 cfu/g in the spleen and 10 2 cfu/g in the liver. Most of the muscle samples were not contaminated. Greater contamination was not found under conditions of stress such as high organic load, a water temperature of 37°C or low levels of dissolved oxygen.