Microbial Source Tracking
Microbial source tracking techniques compare microorganisms in water to those from known fecal pollution sources. The techniques get more information from a water sample beyond the number of fecal indicator bacteria like Escherichia coli (E. coli).
While E. coli detection indicates fecal pollution, it does not indicate the pollution source because E. coli can come from many different mammals and birds, in addition to humans. E. coli can even come from secondary sources such as resuspended beach sands or river sediments. Microbial source tracking techniques detect other indicator bacteria, for example those found only in the human gut, helping infer a sewage source of fecal pollution and E. coli.
Edge-Water DNA Inc. looks in water samples for specific DNA sequences of bacteria unique to a human or animal gut. We can also look in water samples for cells from the lining of a human or animal gut that are regularly sloughed off in feces.
We use a digital polymerase chain reaction (PCR) method to get the number of copies of a specific DNA sequence in a water sample. We can detect fecal pollution from human, dog, gull, Canada geese, ruminant, cow, and pig fecal sources.
Some general background on microbial source tracking in Canada:
