Antibiotic Resistant Bacteria: A Factor to be Considered in Safe Drinking Water

Wastewater management has been subjected to different treatment technologies using chemical and biological techniques for several decades in order to protect the environment and public health. Biological treatment is based on microbial capability to reduce the pathogens load to achieve the lowest environmental as well as public health risks. However, such treatment is often neglecting the fact that bacteria resistant ability to antibiotics may increase during sewage treatment processes. This study aims to demonstrate the evidence of antibiotic resistant or multiple-antibiotic resistant (MAR) bacteria in water even after treatment, which can contribute to the increase their existence among the bacterial population. The study objective is extend to prove that the public health risk from the high existence of MAR population in drinking water begin to be much more complicated if the antibiotic resistance character is transferable from non-pathogenic bacteria to pathogens or opportunistic pathogens. The study showed that most bacterial species isolated from chlorinated water at two districts in Cairo, Egypt were resistance to ampicillin, sulfaguanidine and streptomycin. MAR bacteria represented 62.4 to 98% of the isolates. Antibiotic resistant bacteria could represent 40% to 70% of the isolates from the distributed drinking water. Bacterial isolates from wells at three water works in Cairo showed resistance to penicillin, 2-sulfanilamide pyrimidine, tetracyclin, chloramphenicol and neomycin. Study on the impact of activated carbon application in a pilot water treatment plant showed that the incidence of coliforms resistant strains among isolates varied significantly according to the source of water samples. MAR was not always high in the same samples in which the overall resistance was high. The antibiotic resistance character was mostly transferable. Accordingly and as a conclusion, the incidence of antibiotic resistant bacteria should be considered as valuable parameter in both wastewater treatment evalauation and in the new drinking water standards.