E. Coli vs. Total Coliform

Attribute	E. Coli	Total Coliform
Classification	Bacteria	Bacteria
Presence in Water	Indicator of fecal contamination	Indicator of general contamination
Health Risks	Can cause severe illness	Generally not harmful, but can indicate potential contamination
Regulatory Limits	Regulated by EPA for drinking water	Regulated by EPA for drinking water

Introduction

When it comes to water quality testing, two common indicators that are often used are E. Coli and Total Coliform. These bacteria are found in the environment and can be used as markers for fecal contamination in water sources. While both E. Coli and Total Coliform are important indicators of water quality, they have distinct attributes that set them apart. In this article, we will compare the attributes of E. Coli and Total Coliform to better understand their differences and similarities.

Origin and Presence

E. Coli, short for Escherichia Coli, is a type of bacteria that is commonly found in the intestines of humans and animals. It is a specific type of coliform bacteria that is used as an indicator of fecal contamination in water. On the other hand, Total Coliform is a broader category of bacteria that includes various species such as E. Coli, Klebsiella, and Enterobacter. Total Coliform bacteria are found in soil, vegetation, and water sources, and their presence can indicate potential contamination.

Health Risks

E. Coli is known to cause various illnesses in humans, including diarrhea, urinary tract infections, and even more severe conditions such as kidney failure. It is considered a pathogenic bacteria that can pose serious health risks if ingested through contaminated water or food. Total Coliform, on the other hand, is not necessarily harmful on its own. While the presence of Total Coliform in water can indicate potential fecal contamination, it does not necessarily mean that the water is unsafe to drink. Further testing for E. Coli is usually required to determine the actual health risks.

Regulatory Standards

Both E. Coli and Total Coliform are regulated by government agencies such as the Environmental Protection Agency (EPA) in the United States. The EPA has established maximum contaminant levels (MCLs) for E. Coli in drinking water to ensure public health and safety. Water systems are required to monitor and report levels of E. Coli to comply with these regulations. Total Coliform, on the other hand, is used as an indicator of water quality but does not have specific MCLs like E. Coli. However, the presence of Total Coliform in drinking water can trigger further investigation and corrective actions by water systems.

Testing Methods

Testing for E. Coli and Total Coliform in water samples is typically done using similar methods, such as membrane filtration or multiple tube fermentation. These methods involve culturing bacteria from water samples on specific media to detect their presence. E. Coli can be distinguished from other coliform bacteria by additional confirmatory tests, such as the presence of beta-glucuronidase enzyme. Total Coliform testing, on the other hand, provides a general indication of bacterial contamination without specifically identifying the species present.

Environmental Factors

The presence of E. Coli and Total Coliform in water sources can be influenced by various environmental factors. Factors such as temperature, pH, and nutrient availability can affect the growth and survival of these bacteria in water. E. Coli, being a specific type of coliform bacteria, may be more indicative of recent fecal contamination in water sources. Total Coliform, on the other hand, can persist in the environment for longer periods and may not always be directly linked to fecal contamination.

Conclusion

In conclusion, E. Coli and Total Coliform are important indicators of water quality that are commonly used in water testing. While E. Coli is a specific type of coliform bacteria that poses health risks and is regulated by specific standards, Total Coliform is a broader category of bacteria that serves as a general indicator of water quality. Understanding the attributes and differences between E. Coli and Total Coliform is essential for ensuring the safety and quality of drinking water sources.