For over a hundred years, the western world has used coliform as a method of testing water contamination. A quick understanding of this method of testing the level of water contamination:
Coliforms belong to a broad class of bacteria. These bacteria are found freely in our environment. The feces of humans as well as other warm-blooded animals are a source of these bacteria. Coliforms are primarily used as a method for indicating water quality. When coliform bacteria are detected in drinking water; it may be indicative of the potential presence of other harmful, disease-causing organisms. The belief is that wherever coliform bacteria are present, there are chances that other more harmful bacteria could reside with them.
Used as a first step
Pathogens, or disease causing organisms -namely virus, bacteria and protozoa -have to be eliminated from water, or they could cause a range of waterborne diseases such as dysentery, hepatitis, and giardiasis and related ones.
Since it is difficult to physically test every sample of water for specific harm-causing bacteria, protozoa and viruses, testing water for coliform is considered. This makes sense, because it is easier to further test samples that have coliform than to test every sample.
Laboratories have been adapting this method because this is relatively much, much less expensive and less time consuming to implement this method rather than look for every specific pathogen.
Moreover, most laboratories are ill equipped to handle mass testing of huge samples of water. Coliform as a method of testing water contamination is thus a useful tool, because it prevents the incurrence of huge expenses.
Effectiveness of coliform as a method of testing water contaminationThe practical advantages of using coliform as a method of testing water contamination notwithstanding; its effectiveness is open to debate. Some scientists believe that this method is too antiquated. Later methods have been proven to be more effective methods. The Environmental Protection Agency (EPA) for instance, draws up plans for containing water contamination from time to time. Using coliform as a method of testing water contamination is just one small part of these. The agency looks more to methods such as addressing contaminants as groups, which is believed to be more effective. It encourages the development of new technologies that tackle contaminants better, faster and more economically.
However, it is too early to say if these developments will signal the discontinuation of using coliform as a method of testing water contamination in the near future.