Bacteria Source Tracking

Bacteria are a normal and natural part of all terrestrial and aquatic ecosystems and perform a vital decomposition function by mineralizing and cycling nutrients through the ecosystem. In many instances, they also form the basis for some food webs. In some instances, bacteria enter aquatic systems through the deposition of fecal material from any number of organisms. Species of wildlife that contribute intestinal bacteria to the environment include (but are not limited to) waterfowl (ducks and geese), raccoons, otters, ground squirrels, and in some locations deer. In addition, there may be companion animal (dogs and cats primarily) that could contribute intestinal bacteria to the environment. Human DNA can enter aquatic systems from leaky septic systems, leaky sanitary sewer lines, improperly treated discharge from waste water treatment plants, application of biosolids to agricultural land, and direct inputs from individuals who defecate in or near water bodies. Input from cows can occur from dairies, grazing in pastures near stream systems, and various manure sources.

MLJ-LLC conducts bacteriologic source tracking using species-specific Bacteroides markers and real time Polymerase Chain Reaction (RT-PCR) techniques. Amplification is performed and analyses can be done qualitatively or quantitatively. MLJ-LLC collects the samples, filters the water in the field, preserves and stores the samples at -80°F until extraction of the DNA. Care is taken to insure that there is no cross-contamination of samples.