Coliforms vs. E. Coli

Attribute	Coliforms	E. Coli
Classification	Group of bacteria that includes E. Coli	Specific type of coliform bacteria
Presence in environment	Found in soil, water, and digestive tracts of animals	Found in the intestines of warm-blooded animals
Indicator of contamination	Used as an indicator of fecal contamination	Indicator of recent fecal contamination
Pathogenicity	Not necessarily pathogenic	Can cause illness in humans

Introduction

Coliforms and E. coli are both types of bacteria that are commonly found in the environment, including in water, soil, and the intestines of animals and humans. While they are related, there are some key differences between the two that are important to understand. In this article, we will compare the attributes of coliforms and E. coli to provide a better understanding of these bacteria.

Definition and Characteristics

Coliforms are a group of bacteria that are commonly used as indicators of water quality. They are gram-negative, rod-shaped bacteria that are capable of fermenting lactose. Coliforms are found in the intestines of warm-blooded animals and are excreted in feces. E. coli, on the other hand, is a specific type of coliform bacteria that is commonly found in the intestines of humans and other animals. It is also gram-negative and rod-shaped, but it has specific genetic markers that distinguish it from other coliform bacteria.

Presence in the Environment

Coliform bacteria are widespread in the environment and can be found in soil, water, and on plants. They are also commonly found in the intestines of animals, including humans. E. coli is a specific type of coliform bacteria that is found in the intestines of warm-blooded animals, including humans. It is commonly used as an indicator of fecal contamination in water sources, as its presence indicates the potential presence of other harmful pathogens.

Health Risks

While most coliform bacteria are not harmful, their presence in water sources can indicate the potential presence of other harmful pathogens, such as viruses and parasites. E. coli, on the other hand, is a known pathogen that can cause serious illness in humans. Ingesting food or water contaminated with E. coli can lead to symptoms such as diarrhea, abdominal cramps, and fever. In severe cases, it can even lead to kidney failure and death.

Testing Methods

Coliform bacteria are commonly tested for using a method called the coliform test, which involves culturing a water sample on a selective medium that encourages the growth of coliform bacteria. E. coli can be specifically identified using a method called the E. coli test, which involves testing for the presence of specific genetic markers that are unique to E. coli bacteria. Both tests are important for monitoring water quality and ensuring the safety of drinking water.

Regulatory Standards

Regulatory agencies, such as the Environmental Protection Agency (EPA), have established standards for coliform bacteria in drinking water. The EPA requires that public water systems test for coliform bacteria on a regular basis and take corrective action if levels exceed the established standards. E. coli is specifically regulated by the EPA, which has set a maximum contaminant level for E. coli in drinking water to protect public health.

Conclusion

In conclusion, coliforms and E. coli are both types of bacteria that are commonly found in the environment and are used as indicators of water quality. While coliform bacteria are generally not harmful, E. coli is a known pathogen that can cause serious illness in humans. Understanding the differences between coliforms and E. coli is important for monitoring water quality and ensuring the safety of drinking water.