Sulfite reducing bacteria are often an indicator of ground water and drinking water contamination. They can be found in decaying vegetation, marine sediment, in soil and the intestinal tract of humans and other vertebrates.
Most sulfite reducing bacteria are non-pathogenic but some of them produce the most potent biological toxins. C. perfingens, associated with fecal contamination, is responsible for food poisoning. Other sulfite reducing bacteria include C. tetani is responsible for tetanus infections and C. botulinum causes botulism.
These procedures are for the enumeration of sulfite reducing anaerobic bacteria or specifically sulfite reducing clostridia using a pour plate method.