Sulfur Reducing Bacteria (SRB)
Sulfur Reducing Bacteria (SRB)
Contaminant Name:
Sulfur Reducing Bacteria (SRB)
What are Sulfur Reducing Bacteria (SRB)?Sulfur Reducing Bacteria (SRB) are a group of bacteria that produce hydrogen sulfide
as part of their natural metabolism. They are present in the environment and also in the
digestive tracts of humans and animals. Their presence may indicate fecal contamination.
SRB were selected for rainwater quality assessment in this study because this group of
bacteria can grow at room temperature and therefore the experiment can easily be done
at home of the participant.
What happens when SRB enters the environment?SRB are commonly found throughout the environment. This is because sulfur occurs
widely in the environment – especially in pond sediments and other areas that are rich in
decaying organic material. In such environments, SRB are of high ecological importance,
as they help in reducing large organic molecules (including contaminants harmful to
human health) into smaller, non-toxic compounds.
How can SRB affect my health?SRB are usually not associated with any illnesses. The hydrogen sulfide that they produce
has a very noxious, rotten egg smell but does not cause harm at the concentrations
produced for this study.
Where can I get more information on SRB?
Important note: The use of SRB for assessment of contamination is very unique to this project. Though preliminary research suggests that SRB may be a strong indicator of fecal contamination, this has not been tested in harvested rainwater or in the American Southwest. In the third year of the project, we will compare the number of E. coli and Total Coliforms (for which there are standards) to the number of SRB (for which there are no standards) in each sample. We hope to discover that homeowners will be able to use a kit that identifies a non-pathogenic organism (SRB) to assess the quality of their harvested rainwater. This would be very exciting, given that at-home kits for microbial water quality assessment do not exist.
Results shown below the Method Limit of Detection (MLOD) were measured at a time when the instrument's ability to detect was better, which provided a lower MLOD than shown here.
